fs/ext4/super.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/ext4/super.c
   4  *
   5  * Copyright (C) 1992, 1993, 1994, 1995
   6  * Remy Card (card@masi.ibp.fr)
   7  * Laboratoire MASI - Institut Blaise Pascal
   8  * Universite Pierre et Marie Curie (Paris VI)
   9  *
  10  *  from
  11  *
  12  *  linux/fs/minix/inode.c
  13  *
  14  *  Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  *  Big-endian to little-endian byte-swapping/bitmaps by
  17  *        David S. Miller (davem@caip.rutgers.edu), 1995
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/string.h>
  22 #include <linux/fs.h>
  23 #include <linux/time.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/backing-dev.h>
  29 #include <linux/parser.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/dax.h>
  42 #include <linux/uaccess.h>
  43 #include <linux/iversion.h>
  44 #include <linux/unicode.h>
  45 #include <linux/part_stat.h>
  46 #include <linux/kthread.h>
  47 #include <linux/freezer.h>
  48 #include <linux/fsnotify.h>
  49 #include <linux/fs_context.h>
  50 #include <linux/fs_parser.h>
  51
  52 #include "ext4.h"
  53 #include "ext4_extents.h"       /* Needed for trace points definition */
  54 #include "ext4_jbd2.h"
  55 #include "xattr.h"
  56 #include "acl.h"
  57 #include "mballoc.h"
  58 #include "fsmap.h"
  59
  60 #define CREATE_TRACE_POINTS
  61 #include <trace/events/ext4.h>
  62
  63 static struct ext4_lazy_init *ext4_li_info;
  64 static DEFINE_MUTEX(ext4_li_mtx);
  65 static struct ratelimit_state ext4_mount_msg_ratelimit;
  66
  67 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  68                              unsigned long journal_devnum);
  69 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  70 static void ext4_update_super(struct super_block *sb);
  71 static int ext4_commit_super(struct super_block *sb);
  72 static int ext4_mark_recovery_complete(struct super_block *sb,
  73                                         struct ext4_super_block *es);
  74 static int ext4_clear_journal_err(struct super_block *sb,
  75                                   struct ext4_super_block *es);
  76 static int ext4_sync_fs(struct super_block *sb, int wait);
  77 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  78 static int ext4_unfreeze(struct super_block *sb);
  79 static int ext4_freeze(struct super_block *sb);
  80 static inline int ext2_feature_set_ok(struct super_block *sb);
  81 static inline int ext3_feature_set_ok(struct super_block *sb);
  82 static void ext4_destroy_lazyinit_thread(void);
  83 static void ext4_unregister_li_request(struct super_block *sb);
  84 static void ext4_clear_request_list(void);
  85 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  86                                             unsigned int journal_inum);
  87 static int ext4_validate_options(struct fs_context *fc);
  88 static int ext4_check_opt_consistency(struct fs_context *fc,
  89                                       struct super_block *sb);
  90 static void ext4_apply_options(struct fs_context *fc, struct super_block *sb);
  91 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param);
  92 static int ext4_get_tree(struct fs_context *fc);
  93 static int ext4_reconfigure(struct fs_context *fc);
  94 static void ext4_fc_free(struct fs_context *fc);
  95 static int ext4_init_fs_context(struct fs_context *fc);
  96 static const struct fs_parameter_spec ext4_param_specs[];
  97
  98 /*
  99  * Lock ordering
 100  *
 101  * page fault path:
 102  * mmap_lock -> sb_start_pagefault -> invalidate_lock (r) -> transaction start
 103  *   -> page lock -> i_data_sem (rw)
 104  *
 105  * buffered write path:
 106  * sb_start_write -> i_mutex -> mmap_lock
 107  * sb_start_write -> i_mutex -> transaction start -> page lock ->
 108  *   i_data_sem (rw)
 109  *
 110  * truncate:
 111  * sb_start_write -> i_mutex -> invalidate_lock (w) -> i_mmap_rwsem (w) ->
 112  *   page lock
 113  * sb_start_write -> i_mutex -> invalidate_lock (w) -> transaction start ->
 114  *   i_data_sem (rw)
 115  *
 116  * direct IO:
 117  * sb_start_write -> i_mutex -> mmap_lock
 118  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
 119  *
 120  * writepages:
 121  * transaction start -> page lock(s) -> i_data_sem (rw)
 122  */
 123
 124 static const struct fs_context_operations ext4_context_ops = {
 125         .parse_param    = ext4_parse_param,
 126         .get_tree       = ext4_get_tree,
 127         .reconfigure    = ext4_reconfigure,
 128         .free           = ext4_fc_free,
 129 };
 130
 131
 132 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 133 static struct file_system_type ext2_fs_type = {
 134         .owner                  = THIS_MODULE,
 135         .name                   = "ext2",
 136         .init_fs_context        = ext4_init_fs_context,
 137         .parameters             = ext4_param_specs,
 138         .kill_sb                = kill_block_super,
 139         .fs_flags               = FS_REQUIRES_DEV,
 140 };
 141 MODULE_ALIAS_FS("ext2");
 142 MODULE_ALIAS("ext2");
 143 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
 144 #else
 145 #define IS_EXT2_SB(sb) (0)
 146 #endif
 147
 148
 149 static struct file_system_type ext3_fs_type = {
 150         .owner                  = THIS_MODULE,
 151         .name                   = "ext3",
 152         .init_fs_context        = ext4_init_fs_context,
 153         .parameters             = ext4_param_specs,
 154         .kill_sb                = kill_block_super,
 155         .fs_flags               = FS_REQUIRES_DEV,
 156 };
 157 MODULE_ALIAS_FS("ext3");
 158 MODULE_ALIAS("ext3");
 159 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 160
 161
 162 static inline void __ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags,
 163                                   bh_end_io_t *end_io)
 164 {
 165         /*
 166          * buffer's verified bit is no longer valid after reading from
 167          * disk again due to write out error, clear it to make sure we
 168          * recheck the buffer contents.
 169          */
 170         clear_buffer_verified(bh);
 171
 172         bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
 173         get_bh(bh);
 174         submit_bh(REQ_OP_READ | op_flags, bh);
 175 }
 176
 177 void ext4_read_bh_nowait(struct buffer_head *bh, blk_opf_t op_flags,
 178                          bh_end_io_t *end_io)
 179 {
 180         BUG_ON(!buffer_locked(bh));
 181
 182         if (ext4_buffer_uptodate(bh)) {
 183                 unlock_buffer(bh);
 184                 return;
 185         }
 186         __ext4_read_bh(bh, op_flags, end_io);
 187 }
 188
 189 int ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags, bh_end_io_t *end_io)
 190 {
 191         BUG_ON(!buffer_locked(bh));
 192
 193         if (ext4_buffer_uptodate(bh)) {
 194                 unlock_buffer(bh);
 195                 return 0;
 196         }
 197
 198         __ext4_read_bh(bh, op_flags, end_io);
 199
 200         wait_on_buffer(bh);
 201         if (buffer_uptodate(bh))
 202                 return 0;
 203         return -EIO;
 204 }
 205
 206 int ext4_read_bh_lock(struct buffer_head *bh, blk_opf_t op_flags, bool wait)
 207 {
 208         lock_buffer(bh);
 209         if (!wait) {
 210                 ext4_read_bh_nowait(bh, op_flags, NULL);
 211                 return 0;
 212         }
 213         return ext4_read_bh(bh, op_flags, NULL);
 214 }
 215
 216 /*
 217  * This works like __bread_gfp() except it uses ERR_PTR for error
 218  * returns.  Currently with sb_bread it's impossible to distinguish
 219  * between ENOMEM and EIO situations (since both result in a NULL
 220  * return.
 221  */
 222 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
 223                                                sector_t block,
 224                                                blk_opf_t op_flags, gfp_t gfp)
 225 {
 226         struct buffer_head *bh;
 227         int ret;
 228
 229         bh = sb_getblk_gfp(sb, block, gfp);
 230         if (bh == NULL)
 231                 return ERR_PTR(-ENOMEM);
 232         if (ext4_buffer_uptodate(bh))
 233                 return bh;
 234
 235         ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
 236         if (ret) {
 237                 put_bh(bh);
 238                 return ERR_PTR(ret);
 239         }
 240         return bh;
 241 }
 242
 243 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
 244                                    blk_opf_t op_flags)
 245 {
 246         return __ext4_sb_bread_gfp(sb, block, op_flags, __GFP_MOVABLE);
 247 }
 248
 249 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
 250                                             sector_t block)
 251 {
 252         return __ext4_sb_bread_gfp(sb, block, 0, 0);
 253 }
 254
 255 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
 256 {
 257         struct buffer_head *bh = sb_getblk_gfp(sb, block, 0);
 258
 259         if (likely(bh)) {
 260                 if (trylock_buffer(bh))
 261                         ext4_read_bh_nowait(bh, REQ_RAHEAD, NULL);
 262                 brelse(bh);
 263         }
 264 }
 265
 266 static int ext4_verify_csum_type(struct super_block *sb,
 267                                  struct ext4_super_block *es)
 268 {
 269         if (!ext4_has_feature_metadata_csum(sb))
 270                 return 1;
 271
 272         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 273 }
 274
 275 __le32 ext4_superblock_csum(struct super_block *sb,
 276                             struct ext4_super_block *es)
 277 {
 278         struct ext4_sb_info *sbi = EXT4_SB(sb);
 279         int offset = offsetof(struct ext4_super_block, s_checksum);
 280         __u32 csum;
 281
 282         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 283
 284         return cpu_to_le32(csum);
 285 }
 286
 287 static int ext4_superblock_csum_verify(struct super_block *sb,
 288                                        struct ext4_super_block *es)
 289 {
 290         if (!ext4_has_metadata_csum(sb))
 291                 return 1;
 292
 293         return es->s_checksum == ext4_superblock_csum(sb, es);
 294 }
 295
 296 void ext4_superblock_csum_set(struct super_block *sb)
 297 {
 298         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 299
 300         if (!ext4_has_metadata_csum(sb))
 301                 return;
 302
 303         es->s_checksum = ext4_superblock_csum(sb, es);
 304 }
 305
 306 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 307                                struct ext4_group_desc *bg)
 308 {
 309         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 310                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 311                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 312 }
 313
 314 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 315                                struct ext4_group_desc *bg)
 316 {
 317         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 318                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 319                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 320 }
 321
 322 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 323                               struct ext4_group_desc *bg)
 324 {
 325         return le32_to_cpu(bg->bg_inode_table_lo) |
 326                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 327                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 328 }
 329
 330 __u32 ext4_free_group_clusters(struct super_block *sb,
 331                                struct ext4_group_desc *bg)
 332 {
 333         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 334                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 335                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 336 }
 337
 338 __u32 ext4_free_inodes_count(struct super_block *sb,
 339                               struct ext4_group_desc *bg)
 340 {
 341         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 342                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 343                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 344 }
 345
 346 __u32 ext4_used_dirs_count(struct super_block *sb,
 347                               struct ext4_group_desc *bg)
 348 {
 349         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 350                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 351                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 352 }
 353
 354 __u32 ext4_itable_unused_count(struct super_block *sb,
 355                               struct ext4_group_desc *bg)
 356 {
 357         return le16_to_cpu(bg->bg_itable_unused_lo) |
 358                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 359                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 360 }
 361
 362 void ext4_block_bitmap_set(struct super_block *sb,
 363                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 364 {
 365         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 366         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 367                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 368 }
 369
 370 void ext4_inode_bitmap_set(struct super_block *sb,
 371                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 372 {
 373         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 374         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 375                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 376 }
 377
 378 void ext4_inode_table_set(struct super_block *sb,
 379                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 380 {
 381         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 382         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 383                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 384 }
 385
 386 void ext4_free_group_clusters_set(struct super_block *sb,
 387                                   struct ext4_group_desc *bg, __u32 count)
 388 {
 389         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 390         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 391                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 392 }
 393
 394 void ext4_free_inodes_set(struct super_block *sb,
 395                           struct ext4_group_desc *bg, __u32 count)
 396 {
 397         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 398         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 399                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 400 }
 401
 402 void ext4_used_dirs_set(struct super_block *sb,
 403                           struct ext4_group_desc *bg, __u32 count)
 404 {
 405         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 406         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 407                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 408 }
 409
 410 void ext4_itable_unused_set(struct super_block *sb,
 411                           struct ext4_group_desc *bg, __u32 count)
 412 {
 413         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 414         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 415                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 416 }
 417
 418 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi, time64_t now)
 419 {
 420         now = clamp_val(now, 0, (1ull << 40) - 1);
 421
 422         *lo = cpu_to_le32(lower_32_bits(now));
 423         *hi = upper_32_bits(now);
 424 }
 425
 426 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 427 {
 428         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 429 }
 430 #define ext4_update_tstamp(es, tstamp) \
 431         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi, \
 432                              ktime_get_real_seconds())
 433 #define ext4_get_tstamp(es, tstamp) \
 434         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 435
 436 /*
 437  * The del_gendisk() function uninitializes the disk-specific data
 438  * structures, including the bdi structure, without telling anyone
 439  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 440  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 441  * This is a kludge to prevent these oops until we can put in a proper
 442  * hook in del_gendisk() to inform the VFS and file system layers.
 443  */
 444 static int block_device_ejected(struct super_block *sb)
 445 {
 446         struct inode *bd_inode = sb->s_bdev->bd_inode;
 447         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 448
 449         return bdi->dev == NULL;
 450 }
 451
 452 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 453 {
 454         struct super_block              *sb = journal->j_private;
 455         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 456         int                             error = is_journal_aborted(journal);
 457         struct ext4_journal_cb_entry    *jce;
 458
 459         BUG_ON(txn->t_state == T_FINISHED);
 460
 461         ext4_process_freed_data(sb, txn->t_tid);
 462
 463         spin_lock(&sbi->s_md_lock);
 464         while (!list_empty(&txn->t_private_list)) {
 465                 jce = list_entry(txn->t_private_list.next,
 466                                  struct ext4_journal_cb_entry, jce_list);
 467                 list_del_init(&jce->jce_list);
 468                 spin_unlock(&sbi->s_md_lock);
 469                 jce->jce_func(sb, jce, error);
 470                 spin_lock(&sbi->s_md_lock);
 471         }
 472         spin_unlock(&sbi->s_md_lock);
 473 }
 474
 475 /*
 476  * This writepage callback for write_cache_pages()
 477  * takes care of a few cases after page cleaning.
 478  *
 479  * write_cache_pages() already checks for dirty pages
 480  * and calls clear_page_dirty_for_io(), which we want,
 481  * to write protect the pages.
 482  *
 483  * However, we may have to redirty a page (see below.)
 484  */
 485 static int ext4_journalled_writepage_callback(struct page *page,
 486                                               struct writeback_control *wbc,
 487                                               void *data)
 488 {
 489         transaction_t *transaction = (transaction_t *) data;
 490         struct buffer_head *bh, *head;
 491         struct journal_head *jh;
 492
 493         bh = head = page_buffers(page);
 494         do {
 495                 /*
 496                  * We have to redirty a page in these cases:
 497                  * 1) If buffer is dirty, it means the page was dirty because it
 498                  * contains a buffer that needs checkpointing. So the dirty bit
 499                  * needs to be preserved so that checkpointing writes the buffer
 500                  * properly.
 501                  * 2) If buffer is not part of the committing transaction
 502                  * (we may have just accidentally come across this buffer because
 503                  * inode range tracking is not exact) or if the currently running
 504                  * transaction already contains this buffer as well, dirty bit
 505                  * needs to be preserved so that the buffer gets writeprotected
 506                  * properly on running transaction's commit.
 507                  */
 508                 jh = bh2jh(bh);
 509                 if (buffer_dirty(bh) ||
 510                     (jh && (jh->b_transaction != transaction ||
 511                             jh->b_next_transaction))) {
 512                         redirty_page_for_writepage(wbc, page);
 513                         goto out;
 514                 }
 515         } while ((bh = bh->b_this_page) != head);
 516
 517 out:
 518         return AOP_WRITEPAGE_ACTIVATE;
 519 }
 520
 521 static int ext4_journalled_submit_inode_data_buffers(struct jbd2_inode *jinode)
 522 {
 523         struct address_space *mapping = jinode->i_vfs_inode->i_mapping;
 524         struct writeback_control wbc = {
 525                 .sync_mode =  WB_SYNC_ALL,
 526                 .nr_to_write = LONG_MAX,
 527                 .range_start = jinode->i_dirty_start,
 528                 .range_end = jinode->i_dirty_end,
 529         };
 530
 531         return write_cache_pages(mapping, &wbc,
 532                                  ext4_journalled_writepage_callback,
 533                                  jinode->i_transaction);
 534 }
 535
 536 static int ext4_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
 537 {
 538         int ret;
 539
 540         if (ext4_should_journal_data(jinode->i_vfs_inode))
 541                 ret = ext4_journalled_submit_inode_data_buffers(jinode);
 542         else
 543                 ret = jbd2_journal_submit_inode_data_buffers(jinode);
 544
 545         return ret;
 546 }
 547
 548 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
 549 {
 550         int ret = 0;
 551
 552         if (!ext4_should_journal_data(jinode->i_vfs_inode))
 553                 ret = jbd2_journal_finish_inode_data_buffers(jinode);
 554
 555         return ret;
 556 }
 557
 558 static bool system_going_down(void)
 559 {
 560         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 561                 || system_state == SYSTEM_RESTART;
 562 }
 563
 564 struct ext4_err_translation {
 565         int code;
 566         int errno;
 567 };
 568
 569 #define EXT4_ERR_TRANSLATE(err) { .code = EXT4_ERR_##err, .errno = err }
 570
 571 static struct ext4_err_translation err_translation[] = {
 572         EXT4_ERR_TRANSLATE(EIO),
 573         EXT4_ERR_TRANSLATE(ENOMEM),
 574         EXT4_ERR_TRANSLATE(EFSBADCRC),
 575         EXT4_ERR_TRANSLATE(EFSCORRUPTED),
 576         EXT4_ERR_TRANSLATE(ENOSPC),
 577         EXT4_ERR_TRANSLATE(ENOKEY),
 578         EXT4_ERR_TRANSLATE(EROFS),
 579         EXT4_ERR_TRANSLATE(EFBIG),
 580         EXT4_ERR_TRANSLATE(EEXIST),
 581         EXT4_ERR_TRANSLATE(ERANGE),
 582         EXT4_ERR_TRANSLATE(EOVERFLOW),
 583         EXT4_ERR_TRANSLATE(EBUSY),
 584         EXT4_ERR_TRANSLATE(ENOTDIR),
 585         EXT4_ERR_TRANSLATE(ENOTEMPTY),
 586         EXT4_ERR_TRANSLATE(ESHUTDOWN),
 587         EXT4_ERR_TRANSLATE(EFAULT),
 588 };
 589
 590 static int ext4_errno_to_code(int errno)
 591 {
 592         int i;
 593
 594         for (i = 0; i < ARRAY_SIZE(err_translation); i++)
 595                 if (err_translation[i].errno == errno)
 596                         return err_translation[i].code;
 597         return EXT4_ERR_UNKNOWN;
 598 }
 599
 600 static void save_error_info(struct super_block *sb, int error,
 601                             __u32 ino, __u64 block,
 602                             const char *func, unsigned int line)
 603 {
 604         struct ext4_sb_info *sbi = EXT4_SB(sb);
 605
 606         /* We default to EFSCORRUPTED error... */
 607         if (error == 0)
 608                 error = EFSCORRUPTED;
 609
 610         spin_lock(&sbi->s_error_lock);
 611         sbi->s_add_error_count++;
 612         sbi->s_last_error_code = error;
 613         sbi->s_last_error_line = line;
 614         sbi->s_last_error_ino = ino;
 615         sbi->s_last_error_block = block;
 616         sbi->s_last_error_func = func;
 617         sbi->s_last_error_time = ktime_get_real_seconds();
 618         if (!sbi->s_first_error_time) {
 619                 sbi->s_first_error_code = error;
 620                 sbi->s_first_error_line = line;
 621                 sbi->s_first_error_ino = ino;
 622                 sbi->s_first_error_block = block;
 623                 sbi->s_first_error_func = func;
 624                 sbi->s_first_error_time = sbi->s_last_error_time;
 625         }
 626         spin_unlock(&sbi->s_error_lock);
 627 }
 628
 629 /* Deal with the reporting of failure conditions on a filesystem such as
 630  * inconsistencies detected or read IO failures.
 631  *
 632  * On ext2, we can store the error state of the filesystem in the
 633  * superblock.  That is not possible on ext4, because we may have other
 634  * write ordering constraints on the superblock which prevent us from
 635  * writing it out straight away; and given that the journal is about to
 636  * be aborted, we can't rely on the current, or future, transactions to
 637  * write out the superblock safely.
 638  *
 639  * We'll just use the jbd2_journal_abort() error code to record an error in
 640  * the journal instead.  On recovery, the journal will complain about
 641  * that error until we've noted it down and cleared it.
 642  *
 643  * If force_ro is set, we unconditionally force the filesystem into an
 644  * ABORT|READONLY state, unless the error response on the fs has been set to
 645  * panic in which case we take the easy way out and panic immediately. This is
 646  * used to deal with unrecoverable failures such as journal IO errors or ENOMEM
 647  * at a critical moment in log management.
 648  */
 649 static void ext4_handle_error(struct super_block *sb, bool force_ro, int error,
 650                               __u32 ino, __u64 block,
 651                               const char *func, unsigned int line)
 652 {
 653         journal_t *journal = EXT4_SB(sb)->s_journal;
 654         bool continue_fs = !force_ro && test_opt(sb, ERRORS_CONT);
 655
 656         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 657         if (test_opt(sb, WARN_ON_ERROR))
 658                 WARN_ON_ONCE(1);
 659
 660         if (!continue_fs && !sb_rdonly(sb)) {
 661                 ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
 662                 if (journal)
 663                         jbd2_journal_abort(journal, -EIO);
 664         }
 665
 666         if (!bdev_read_only(sb->s_bdev)) {
 667                 save_error_info(sb, error, ino, block, func, line);
 668                 /*
 669                  * In case the fs should keep running, we need to writeout
 670                  * superblock through the journal. Due to lock ordering
 671                  * constraints, it may not be safe to do it right here so we
 672                  * defer superblock flushing to a workqueue.
 673                  */
 674                 if (continue_fs && journal)
 675                         schedule_work(&EXT4_SB(sb)->s_error_work);
 676                 else
 677                         ext4_commit_super(sb);
 678         }
 679
 680         /*
 681          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 682          * could panic during 'reboot -f' as the underlying device got already
 683          * disabled.
 684          */
 685         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
 686                 panic("EXT4-fs (device %s): panic forced after error\n",
 687                         sb->s_id);
 688         }
 689
 690         if (sb_rdonly(sb) || continue_fs)
 691                 return;
 692
 693         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 694         /*
 695          * Make sure updated value of ->s_mount_flags will be visible before
 696          * ->s_flags update
 697          */
 698         smp_wmb();
 699         sb->s_flags |= SB_RDONLY;
 700 }
 701
 702 static void flush_stashed_error_work(struct work_struct *work)
 703 {
 704         struct ext4_sb_info *sbi = container_of(work, struct ext4_sb_info,
 705                                                 s_error_work);
 706         journal_t *journal = sbi->s_journal;
 707         handle_t *handle;
 708
 709         /*
 710          * If the journal is still running, we have to write out superblock
 711          * through the journal to avoid collisions of other journalled sb
 712          * updates.
 713          *
 714          * We use directly jbd2 functions here to avoid recursing back into
 715          * ext4 error handling code during handling of previous errors.
 716          */
 717         if (!sb_rdonly(sbi->s_sb) && journal) {
 718                 struct buffer_head *sbh = sbi->s_sbh;
 719                 handle = jbd2_journal_start(journal, 1);
 720                 if (IS_ERR(handle))
 721                         goto write_directly;
 722                 if (jbd2_journal_get_write_access(handle, sbh)) {
 723                         jbd2_journal_stop(handle);
 724                         goto write_directly;
 725                 }
 726                 ext4_update_super(sbi->s_sb);
 727                 if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
 728                         ext4_msg(sbi->s_sb, KERN_ERR, "previous I/O error to "
 729                                  "superblock detected");
 730                         clear_buffer_write_io_error(sbh);
 731                         set_buffer_uptodate(sbh);
 732                 }
 733
 734                 if (jbd2_journal_dirty_metadata(handle, sbh)) {
 735                         jbd2_journal_stop(handle);
 736                         goto write_directly;
 737                 }
 738                 jbd2_journal_stop(handle);
 739                 ext4_notify_error_sysfs(sbi);
 740                 return;
 741         }
 742 write_directly:
 743         /*
 744          * Write through journal failed. Write sb directly to get error info
 745          * out and hope for the best.
 746          */
 747         ext4_commit_super(sbi->s_sb);
 748         ext4_notify_error_sysfs(sbi);
 749 }
 750
 751 #define ext4_error_ratelimit(sb)                                        \
 752                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 753                              "EXT4-fs error")
 754
 755 void __ext4_error(struct super_block *sb, const char *function,
 756                   unsigned int line, bool force_ro, int error, __u64 block,
 757                   const char *fmt, ...)
 758 {
 759         struct va_format vaf;
 760         va_list args;
 761
 762         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 763                 return;
 764
 765         trace_ext4_error(sb, function, line);
 766         if (ext4_error_ratelimit(sb)) {
 767                 va_start(args, fmt);
 768                 vaf.fmt = fmt;
 769                 vaf.va = &args;
 770                 printk(KERN_CRIT
 771                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 772                        sb->s_id, function, line, current->comm, &vaf);
 773                 va_end(args);
 774         }
 775         fsnotify_sb_error(sb, NULL, error ? error : EFSCORRUPTED);
 776
 777         ext4_handle_error(sb, force_ro, error, 0, block, function, line);
 778 }
 779
 780 void __ext4_error_inode(struct inode *inode, const char *function,
 781                         unsigned int line, ext4_fsblk_t block, int error,
 782                         const char *fmt, ...)
 783 {
 784         va_list args;
 785         struct va_format vaf;
 786
 787         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 788                 return;
 789
 790         trace_ext4_error(inode->i_sb, function, line);
 791         if (ext4_error_ratelimit(inode->i_sb)) {
 792                 va_start(args, fmt);
 793                 vaf.fmt = fmt;
 794                 vaf.va = &args;
 795                 if (block)
 796                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 797                                "inode #%lu: block %llu: comm %s: %pV\n",
 798                                inode->i_sb->s_id, function, line, inode->i_ino,
 799                                block, current->comm, &vaf);
 800                 else
 801                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 802                                "inode #%lu: comm %s: %pV\n",
 803                                inode->i_sb->s_id, function, line, inode->i_ino,
 804                                current->comm, &vaf);
 805                 va_end(args);
 806         }
 807         fsnotify_sb_error(inode->i_sb, inode, error ? error : EFSCORRUPTED);
 808
 809         ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
 810                           function, line);
 811 }
 812
 813 void __ext4_error_file(struct file *file, const char *function,
 814                        unsigned int line, ext4_fsblk_t block,
 815                        const char *fmt, ...)
 816 {
 817         va_list args;
 818         struct va_format vaf;
 819         struct inode *inode = file_inode(file);
 820         char pathname[80], *path;
 821
 822         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 823                 return;
 824
 825         trace_ext4_error(inode->i_sb, function, line);
 826         if (ext4_error_ratelimit(inode->i_sb)) {
 827                 path = file_path(file, pathname, sizeof(pathname));
 828                 if (IS_ERR(path))
 829                         path = "(unknown)";
 830                 va_start(args, fmt);
 831                 vaf.fmt = fmt;
 832                 vaf.va = &args;
 833                 if (block)
 834                         printk(KERN_CRIT
 835                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 836                                "block %llu: comm %s: path %s: %pV\n",
 837                                inode->i_sb->s_id, function, line, inode->i_ino,
 838                                block, current->comm, path, &vaf);
 839                 else
 840                         printk(KERN_CRIT
 841                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 842                                "comm %s: path %s: %pV\n",
 843                                inode->i_sb->s_id, function, line, inode->i_ino,
 844                                current->comm, path, &vaf);
 845                 va_end(args);
 846         }
 847         fsnotify_sb_error(inode->i_sb, inode, EFSCORRUPTED);
 848
 849         ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
 850                           function, line);
 851 }
 852
 853 const char *ext4_decode_error(struct super_block *sb, int errno,
 854                               char nbuf[16])
 855 {
 856         char *errstr = NULL;
 857
 858         switch (errno) {
 859         case -EFSCORRUPTED:
 860                 errstr = "Corrupt filesystem";
 861                 break;
 862         case -EFSBADCRC:
 863                 errstr = "Filesystem failed CRC";
 864                 break;
 865         case -EIO:
 866                 errstr = "IO failure";
 867                 break;
 868         case -ENOMEM:
 869                 errstr = "Out of memory";
 870                 break;
 871         case -EROFS:
 872                 if (!sb || (EXT4_SB(sb)->s_journal &&
 873                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 874                         errstr = "Journal has aborted";
 875                 else
 876                         errstr = "Readonly filesystem";
 877                 break;
 878         default:
 879                 /* If the caller passed in an extra buffer for unknown
 880                  * errors, textualise them now.  Else we just return
 881                  * NULL. */
 882                 if (nbuf) {
 883                         /* Check for truncated error codes... */
 884                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 885                                 errstr = nbuf;
 886                 }
 887                 break;
 888         }
 889
 890         return errstr;
 891 }
 892
 893 /* __ext4_std_error decodes expected errors from journaling functions
 894  * automatically and invokes the appropriate error response.  */
 895
 896 void __ext4_std_error(struct super_block *sb, const char *function,
 897                       unsigned int line, int errno)
 898 {
 899         char nbuf[16];
 900         const char *errstr;
 901
 902         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 903                 return;
 904
 905         /* Special case: if the error is EROFS, and we're not already
 906          * inside a transaction, then there's really no point in logging
 907          * an error. */
 908         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 909                 return;
 910
 911         if (ext4_error_ratelimit(sb)) {
 912                 errstr = ext4_decode_error(sb, errno, nbuf);
 913                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 914                        sb->s_id, function, line, errstr);
 915         }
 916         fsnotify_sb_error(sb, NULL, errno ? errno : EFSCORRUPTED);
 917
 918         ext4_handle_error(sb, false, -errno, 0, 0, function, line);
 919 }
 920
 921 void __ext4_msg(struct super_block *sb,
 922                 const char *prefix, const char *fmt, ...)
 923 {
 924         struct va_format vaf;
 925         va_list args;
 926
 927         if (sb) {
 928                 atomic_inc(&EXT4_SB(sb)->s_msg_count);
 929                 if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state),
 930                                   "EXT4-fs"))
 931                         return;
 932         }
 933
 934         va_start(args, fmt);
 935         vaf.fmt = fmt;
 936         vaf.va = &args;
 937         if (sb)
 938                 printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 939         else
 940                 printk("%sEXT4-fs: %pV\n", prefix, &vaf);
 941         va_end(args);
 942 }
 943
 944 static int ext4_warning_ratelimit(struct super_block *sb)
 945 {
 946         atomic_inc(&EXT4_SB(sb)->s_warning_count);
 947         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
 948                             "EXT4-fs warning");
 949 }
 950
 951 void __ext4_warning(struct super_block *sb, const char *function,
 952                     unsigned int line, const char *fmt, ...)
 953 {
 954         struct va_format vaf;
 955         va_list args;
 956
 957         if (!ext4_warning_ratelimit(sb))
 958                 return;
 959
 960         va_start(args, fmt);
 961         vaf.fmt = fmt;
 962         vaf.va = &args;
 963         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 964                sb->s_id, function, line, &vaf);
 965         va_end(args);
 966 }
 967
 968 void __ext4_warning_inode(const struct inode *inode, const char *function,
 969                           unsigned int line, const char *fmt, ...)
 970 {
 971         struct va_format vaf;
 972         va_list args;
 973
 974         if (!ext4_warning_ratelimit(inode->i_sb))
 975                 return;
 976
 977         va_start(args, fmt);
 978         vaf.fmt = fmt;
 979         vaf.va = &args;
 980         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 981                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 982                function, line, inode->i_ino, current->comm, &vaf);
 983         va_end(args);
 984 }
 985
 986 void __ext4_grp_locked_error(const char *function, unsigned int line,
 987                              struct super_block *sb, ext4_group_t grp,
 988                              unsigned long ino, ext4_fsblk_t block,
 989                              const char *fmt, ...)
 990 __releases(bitlock)
 991 __acquires(bitlock)
 992 {
 993         struct va_format vaf;
 994         va_list args;
 995
 996         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 997                 return;
 998
 999         trace_ext4_error(sb, function, line);
1000         if (ext4_error_ratelimit(sb)) {
1001                 va_start(args, fmt);
1002                 vaf.fmt = fmt;
1003                 vaf.va = &args;
1004                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
1005                        sb->s_id, function, line, grp);
1006                 if (ino)
1007                         printk(KERN_CONT "inode %lu: ", ino);
1008                 if (block)
1009                         printk(KERN_CONT "block %llu:",
1010                                (unsigned long long) block);
1011                 printk(KERN_CONT "%pV\n", &vaf);
1012                 va_end(args);
1013         }
1014
1015         if (test_opt(sb, ERRORS_CONT)) {
1016                 if (test_opt(sb, WARN_ON_ERROR))
1017                         WARN_ON_ONCE(1);
1018                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
1019                 if (!bdev_read_only(sb->s_bdev)) {
1020                         save_error_info(sb, EFSCORRUPTED, ino, block, function,
1021                                         line);
1022                         schedule_work(&EXT4_SB(sb)->s_error_work);
1023                 }
1024                 return;
1025         }
1026         ext4_unlock_group(sb, grp);
1027         ext4_handle_error(sb, false, EFSCORRUPTED, ino, block, function, line);
1028         /*
1029          * We only get here in the ERRORS_RO case; relocking the group
1030          * may be dangerous, but nothing bad will happen since the
1031          * filesystem will have already been marked read/only and the
1032          * journal has been aborted.  We return 1 as a hint to callers
1033          * who might what to use the return value from
1034          * ext4_grp_locked_error() to distinguish between the
1035          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1036          * aggressively from the ext4 function in question, with a
1037          * more appropriate error code.
1038          */
1039         ext4_lock_group(sb, grp);
1040         return;
1041 }
1042
1043 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1044                                      ext4_group_t group,
1045                                      unsigned int flags)
1046 {
1047         struct ext4_sb_info *sbi = EXT4_SB(sb);
1048         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1049         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1050         int ret;
1051
1052         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1053                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1054                                             &grp->bb_state);
1055                 if (!ret)
1056                         percpu_counter_sub(&sbi->s_freeclusters_counter,
1057                                            grp->bb_free);
1058         }
1059
1060         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1061                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1062                                             &grp->bb_state);
1063                 if (!ret && gdp) {
1064                         int count;
1065
1066                         count = ext4_free_inodes_count(sb, gdp);
1067                         percpu_counter_sub(&sbi->s_freeinodes_counter,
1068                                            count);
1069                 }
1070         }
1071 }
1072
1073 void ext4_update_dynamic_rev(struct super_block *sb)
1074 {
1075         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1076
1077         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1078                 return;
1079
1080         ext4_warning(sb,
1081                      "updating to rev %d because of new feature flag, "
1082                      "running e2fsck is recommended",
1083                      EXT4_DYNAMIC_REV);
1084
1085         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1086         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1087         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1088         /* leave es->s_feature_*compat flags alone */
1089         /* es->s_uuid will be set by e2fsck if empty */
1090
1091         /*
1092          * The rest of the superblock fields should be zero, and if not it
1093          * means they are likely already in use, so leave them alone.  We
1094          * can leave it up to e2fsck to clean up any inconsistencies there.
1095          */
1096 }
1097
1098 /*
1099  * Open the external journal device
1100  */
1101 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
1102 {
1103         struct block_device *bdev;
1104
1105         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
1106         if (IS_ERR(bdev))
1107                 goto fail;
1108         return bdev;
1109
1110 fail:
1111         ext4_msg(sb, KERN_ERR,
1112                  "failed to open journal device unknown-block(%u,%u) %ld",
1113                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
1114         return NULL;
1115 }
1116
1117 /*
1118  * Release the journal device
1119  */
1120 static void ext4_blkdev_put(struct block_device *bdev)
1121 {
1122         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1123 }
1124
1125 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
1126 {
1127         struct block_device *bdev;
1128         bdev = sbi->s_journal_bdev;
1129         if (bdev) {
1130                 ext4_blkdev_put(bdev);
1131                 sbi->s_journal_bdev = NULL;
1132         }
1133 }
1134
1135 static inline struct inode *orphan_list_entry(struct list_head *l)
1136 {
1137         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1138 }
1139
1140 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1141 {
1142         struct list_head *l;
1143
1144         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1145                  le32_to_cpu(sbi->s_es->s_last_orphan));
1146
1147         printk(KERN_ERR "sb_info orphan list:\n");
1148         list_for_each(l, &sbi->s_orphan) {
1149                 struct inode *inode = orphan_list_entry(l);
1150                 printk(KERN_ERR "  "
1151                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1152                        inode->i_sb->s_id, inode->i_ino, inode,
1153                        inode->i_mode, inode->i_nlink,
1154                        NEXT_ORPHAN(inode));
1155         }
1156 }
1157
1158 #ifdef CONFIG_QUOTA
1159 static int ext4_quota_off(struct super_block *sb, int type);
1160
1161 static inline void ext4_quota_off_umount(struct super_block *sb)
1162 {
1163         int type;
1164
1165         /* Use our quota_off function to clear inode flags etc. */
1166         for (type = 0; type < EXT4_MAXQUOTAS; type++)
1167                 ext4_quota_off(sb, type);
1168 }
1169
1170 /*
1171  * This is a helper function which is used in the mount/remount
1172  * codepaths (which holds s_umount) to fetch the quota file name.
1173  */
1174 static inline char *get_qf_name(struct super_block *sb,
1175                                 struct ext4_sb_info *sbi,
1176                                 int type)
1177 {
1178         return rcu_dereference_protected(sbi->s_qf_names[type],
1179                                          lockdep_is_held(&sb->s_umount));
1180 }
1181 #else
1182 static inline void ext4_quota_off_umount(struct super_block *sb)
1183 {
1184 }
1185 #endif
1186
1187 static void ext4_put_super(struct super_block *sb)
1188 {
1189         struct ext4_sb_info *sbi = EXT4_SB(sb);
1190         struct ext4_super_block *es = sbi->s_es;
1191         struct buffer_head **group_desc;
1192         struct flex_groups **flex_groups;
1193         int aborted = 0;
1194         int i, err;
1195
1196         /*
1197          * Unregister sysfs before destroying jbd2 journal.
1198          * Since we could still access attr_journal_task attribute via sysfs
1199          * path which could have sbi->s_journal->j_task as NULL
1200          * Unregister sysfs before flush sbi->s_error_work.
1201          * Since user may read /proc/fs/ext4/xx/mb_groups during umount, If
1202          * read metadata verify failed then will queue error work.
1203          * flush_stashed_error_work will call start_this_handle may trigger
1204          * BUG_ON.
1205          */
1206         ext4_unregister_sysfs(sb);
1207
1208         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs unmount"))
1209                 ext4_msg(sb, KERN_INFO, "unmounting filesystem.");
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         del_timer_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         spin_lock_init(&ei->i_raw_lock);
1327         INIT_LIST_HEAD(&ei->i_prealloc_list);
1328         atomic_set(&ei->i_prealloc_active, 0);
1329         spin_lock_init(&ei->i_prealloc_lock);
1330         ext4_es_init_tree(&ei->i_es_tree);
1331         rwlock_init(&ei->i_es_lock);
1332         INIT_LIST_HEAD(&ei->i_es_list);
1333         ei->i_es_all_nr = 0;
1334         ei->i_es_shk_nr = 0;
1335         ei->i_es_shrink_lblk = 0;
1336         ei->i_reserved_data_blocks = 0;
1337         spin_lock_init(&(ei->i_block_reservation_lock));
1338         ext4_init_pending_tree(&ei->i_pending_tree);
1339 #ifdef CONFIG_QUOTA
1340         ei->i_reserved_quota = 0;
1341         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1342 #endif
1343         ei->jinode = NULL;
1344         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1345         spin_lock_init(&ei->i_completed_io_lock);
1346         ei->i_sync_tid = 0;
1347         ei->i_datasync_tid = 0;
1348         atomic_set(&ei->i_unwritten, 0);
1349         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1350         ext4_fc_init_inode(&ei->vfs_inode);
1351         mutex_init(&ei->i_fc_lock);
1352         return &ei->vfs_inode;
1353 }
1354
1355 static int ext4_drop_inode(struct inode *inode)
1356 {
1357         int drop = generic_drop_inode(inode);
1358
1359         if (!drop)
1360                 drop = fscrypt_drop_inode(inode);
1361
1362         trace_ext4_drop_inode(inode, drop);
1363         return drop;
1364 }
1365
1366 static void ext4_free_in_core_inode(struct inode *inode)
1367 {
1368         fscrypt_free_inode(inode);
1369         if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1370                 pr_warn("%s: inode %ld still in fc list",
1371                         __func__, inode->i_ino);
1372         }
1373         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1374 }
1375
1376 static void ext4_destroy_inode(struct inode *inode)
1377 {
1378         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1379                 ext4_msg(inode->i_sb, KERN_ERR,
1380                          "Inode %lu (%p): orphan list check failed!",
1381                          inode->i_ino, EXT4_I(inode));
1382                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1383                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1384                                 true);
1385                 dump_stack();
1386         }
1387
1388         if (EXT4_I(inode)->i_reserved_data_blocks)
1389                 ext4_msg(inode->i_sb, KERN_ERR,
1390                          "Inode %lu (%p): i_reserved_data_blocks (%u) not cleared!",
1391                          inode->i_ino, EXT4_I(inode),
1392                          EXT4_I(inode)->i_reserved_data_blocks);
1393 }
1394
1395 static void init_once(void *foo)
1396 {
1397         struct ext4_inode_info *ei = foo;
1398
1399         INIT_LIST_HEAD(&ei->i_orphan);
1400         init_rwsem(&ei->xattr_sem);
1401         init_rwsem(&ei->i_data_sem);
1402         inode_init_once(&ei->vfs_inode);
1403         ext4_fc_init_inode(&ei->vfs_inode);
1404 }
1405
1406 static int __init init_inodecache(void)
1407 {
1408         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1409                                 sizeof(struct ext4_inode_info), 0,
1410                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1411                                         SLAB_ACCOUNT),
1412                                 offsetof(struct ext4_inode_info, i_data),
1413                                 sizeof_field(struct ext4_inode_info, i_data),
1414                                 init_once);
1415         if (ext4_inode_cachep == NULL)
1416                 return -ENOMEM;
1417         return 0;
1418 }
1419
1420 static void destroy_inodecache(void)
1421 {
1422         /*
1423          * Make sure all delayed rcu free inodes are flushed before we
1424          * destroy cache.
1425          */
1426         rcu_barrier();
1427         kmem_cache_destroy(ext4_inode_cachep);
1428 }
1429
1430 void ext4_clear_inode(struct inode *inode)
1431 {
1432         ext4_fc_del(inode);
1433         invalidate_inode_buffers(inode);
1434         clear_inode(inode);
1435         ext4_discard_preallocations(inode, 0);
1436         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1437         dquot_drop(inode);
1438         if (EXT4_I(inode)->jinode) {
1439                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1440                                                EXT4_I(inode)->jinode);
1441                 jbd2_free_inode(EXT4_I(inode)->jinode);
1442                 EXT4_I(inode)->jinode = NULL;
1443         }
1444         fscrypt_put_encryption_info(inode);
1445         fsverity_cleanup_inode(inode);
1446 }
1447
1448 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1449                                         u64 ino, u32 generation)
1450 {
1451         struct inode *inode;
1452
1453         /*
1454          * Currently we don't know the generation for parent directory, so
1455          * a generation of 0 means "accept any"
1456          */
1457         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1458         if (IS_ERR(inode))
1459                 return ERR_CAST(inode);
1460         if (generation && inode->i_generation != generation) {
1461                 iput(inode);
1462                 return ERR_PTR(-ESTALE);
1463         }
1464
1465         return inode;
1466 }
1467
1468 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1469                                         int fh_len, int fh_type)
1470 {
1471         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1472                                     ext4_nfs_get_inode);
1473 }
1474
1475 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1476                                         int fh_len, int fh_type)
1477 {
1478         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1479                                     ext4_nfs_get_inode);
1480 }
1481
1482 static int ext4_nfs_commit_metadata(struct inode *inode)
1483 {
1484         struct writeback_control wbc = {
1485                 .sync_mode = WB_SYNC_ALL
1486         };
1487
1488         trace_ext4_nfs_commit_metadata(inode);
1489         return ext4_write_inode(inode, &wbc);
1490 }
1491
1492 #ifdef CONFIG_QUOTA
1493 static const char * const quotatypes[] = INITQFNAMES;
1494 #define QTYPE2NAME(t) (quotatypes[t])
1495
1496 static int ext4_write_dquot(struct dquot *dquot);
1497 static int ext4_acquire_dquot(struct dquot *dquot);
1498 static int ext4_release_dquot(struct dquot *dquot);
1499 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1500 static int ext4_write_info(struct super_block *sb, int type);
1501 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1502                          const struct path *path);
1503 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1504                                size_t len, loff_t off);
1505 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1506                                 const char *data, size_t len, loff_t off);
1507 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1508                              unsigned int flags);
1509
1510 static struct dquot **ext4_get_dquots(struct inode *inode)
1511 {
1512         return EXT4_I(inode)->i_dquot;
1513 }
1514
1515 static const struct dquot_operations ext4_quota_operations = {
1516         .get_reserved_space     = ext4_get_reserved_space,
1517         .write_dquot            = ext4_write_dquot,
1518         .acquire_dquot          = ext4_acquire_dquot,
1519         .release_dquot          = ext4_release_dquot,
1520         .mark_dirty             = ext4_mark_dquot_dirty,
1521         .write_info             = ext4_write_info,
1522         .alloc_dquot            = dquot_alloc,
1523         .destroy_dquot          = dquot_destroy,
1524         .get_projid             = ext4_get_projid,
1525         .get_inode_usage        = ext4_get_inode_usage,
1526         .get_next_id            = dquot_get_next_id,
1527 };
1528
1529 static const struct quotactl_ops ext4_qctl_operations = {
1530         .quota_on       = ext4_quota_on,
1531         .quota_off      = ext4_quota_off,
1532         .quota_sync     = dquot_quota_sync,
1533         .get_state      = dquot_get_state,
1534         .set_info       = dquot_set_dqinfo,
1535         .get_dqblk      = dquot_get_dqblk,
1536         .set_dqblk      = dquot_set_dqblk,
1537         .get_nextdqblk  = dquot_get_next_dqblk,
1538 };
1539 #endif
1540
1541 static const struct super_operations ext4_sops = {
1542         .alloc_inode    = ext4_alloc_inode,
1543         .free_inode     = ext4_free_in_core_inode,
1544         .destroy_inode  = ext4_destroy_inode,
1545         .write_inode    = ext4_write_inode,
1546         .dirty_inode    = ext4_dirty_inode,
1547         .drop_inode     = ext4_drop_inode,
1548         .evict_inode    = ext4_evict_inode,
1549         .put_super      = ext4_put_super,
1550         .sync_fs        = ext4_sync_fs,
1551         .freeze_fs      = ext4_freeze,
1552         .unfreeze_fs    = ext4_unfreeze,
1553         .statfs         = ext4_statfs,
1554         .show_options   = ext4_show_options,
1555 #ifdef CONFIG_QUOTA
1556         .quota_read     = ext4_quota_read,
1557         .quota_write    = ext4_quota_write,
1558         .get_dquots     = ext4_get_dquots,
1559 #endif
1560 };
1561
1562 static const struct export_operations ext4_export_ops = {
1563         .fh_to_dentry = ext4_fh_to_dentry,
1564         .fh_to_parent = ext4_fh_to_parent,
1565         .get_parent = ext4_get_parent,
1566         .commit_metadata = ext4_nfs_commit_metadata,
1567 };
1568
1569 enum {
1570         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1571         Opt_resgid, Opt_resuid, Opt_sb,
1572         Opt_nouid32, Opt_debug, Opt_removed,
1573         Opt_user_xattr, Opt_acl,
1574         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1575         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1576         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1577         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1578         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1579         Opt_inlinecrypt,
1580         Opt_usrjquota, Opt_grpjquota, Opt_quota,
1581         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1582         Opt_usrquota, Opt_grpquota, Opt_prjquota,
1583         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1584         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1585         Opt_nowarn_on_error, Opt_mblk_io_submit, Opt_debug_want_extra_isize,
1586         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1587         Opt_inode_readahead_blks, Opt_journal_ioprio,
1588         Opt_dioread_nolock, Opt_dioread_lock,
1589         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1590         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1591         Opt_no_prefetch_block_bitmaps, Opt_mb_optimize_scan,
1592         Opt_errors, Opt_data, Opt_data_err, Opt_jqfmt, Opt_dax_type,
1593 #ifdef CONFIG_EXT4_DEBUG
1594         Opt_fc_debug_max_replay, Opt_fc_debug_force
1595 #endif
1596 };
1597
1598 static const struct constant_table ext4_param_errors[] = {
1599         {"continue",    EXT4_MOUNT_ERRORS_CONT},
1600         {"panic",       EXT4_MOUNT_ERRORS_PANIC},
1601         {"remount-ro",  EXT4_MOUNT_ERRORS_RO},
1602         {}
1603 };
1604
1605 static const struct constant_table ext4_param_data[] = {
1606         {"journal",     EXT4_MOUNT_JOURNAL_DATA},
1607         {"ordered",     EXT4_MOUNT_ORDERED_DATA},
1608         {"writeback",   EXT4_MOUNT_WRITEBACK_DATA},
1609         {}
1610 };
1611
1612 static const struct constant_table ext4_param_data_err[] = {
1613         {"abort",       Opt_data_err_abort},
1614         {"ignore",      Opt_data_err_ignore},
1615         {}
1616 };
1617
1618 static const struct constant_table ext4_param_jqfmt[] = {
1619         {"vfsold",      QFMT_VFS_OLD},
1620         {"vfsv0",       QFMT_VFS_V0},
1621         {"vfsv1",       QFMT_VFS_V1},
1622         {}
1623 };
1624
1625 static const struct constant_table ext4_param_dax[] = {
1626         {"always",      Opt_dax_always},
1627         {"inode",       Opt_dax_inode},
1628         {"never",       Opt_dax_never},
1629         {}
1630 };
1631
1632 /* String parameter that allows empty argument */
1633 #define fsparam_string_empty(NAME, OPT) \
1634         __fsparam(fs_param_is_string, NAME, OPT, fs_param_can_be_empty, NULL)
1635
1636 /*
1637  * Mount option specification
1638  * We don't use fsparam_flag_no because of the way we set the
1639  * options and the way we show them in _ext4_show_options(). To
1640  * keep the changes to a minimum, let's keep the negative options
1641  * separate for now.
1642  */
1643 static const struct fs_parameter_spec ext4_param_specs[] = {
1644         fsparam_flag    ("bsddf",               Opt_bsd_df),
1645         fsparam_flag    ("minixdf",             Opt_minix_df),
1646         fsparam_flag    ("grpid",               Opt_grpid),
1647         fsparam_flag    ("bsdgroups",           Opt_grpid),
1648         fsparam_flag    ("nogrpid",             Opt_nogrpid),
1649         fsparam_flag    ("sysvgroups",          Opt_nogrpid),
1650         fsparam_u32     ("resgid",              Opt_resgid),
1651         fsparam_u32     ("resuid",              Opt_resuid),
1652         fsparam_u32     ("sb",                  Opt_sb),
1653         fsparam_enum    ("errors",              Opt_errors, ext4_param_errors),
1654         fsparam_flag    ("nouid32",             Opt_nouid32),
1655         fsparam_flag    ("debug",               Opt_debug),
1656         fsparam_flag    ("oldalloc",            Opt_removed),
1657         fsparam_flag    ("orlov",               Opt_removed),
1658         fsparam_flag    ("user_xattr",          Opt_user_xattr),
1659         fsparam_flag    ("acl",                 Opt_acl),
1660         fsparam_flag    ("norecovery",          Opt_noload),
1661         fsparam_flag    ("noload",              Opt_noload),
1662         fsparam_flag    ("bh",                  Opt_removed),
1663         fsparam_flag    ("nobh",                Opt_removed),
1664         fsparam_u32     ("commit",              Opt_commit),
1665         fsparam_u32     ("min_batch_time",      Opt_min_batch_time),
1666         fsparam_u32     ("max_batch_time",      Opt_max_batch_time),
1667         fsparam_u32     ("journal_dev",         Opt_journal_dev),
1668         fsparam_bdev    ("journal_path",        Opt_journal_path),
1669         fsparam_flag    ("journal_checksum",    Opt_journal_checksum),
1670         fsparam_flag    ("nojournal_checksum",  Opt_nojournal_checksum),
1671         fsparam_flag    ("journal_async_commit",Opt_journal_async_commit),
1672         fsparam_flag    ("abort",               Opt_abort),
1673         fsparam_enum    ("data",                Opt_data, ext4_param_data),
1674         fsparam_enum    ("data_err",            Opt_data_err,
1675                                                 ext4_param_data_err),
1676         fsparam_string_empty
1677                         ("usrjquota",           Opt_usrjquota),
1678         fsparam_string_empty
1679                         ("grpjquota",           Opt_grpjquota),
1680         fsparam_enum    ("jqfmt",               Opt_jqfmt, ext4_param_jqfmt),
1681         fsparam_flag    ("grpquota",            Opt_grpquota),
1682         fsparam_flag    ("quota",               Opt_quota),
1683         fsparam_flag    ("noquota",             Opt_noquota),
1684         fsparam_flag    ("usrquota",            Opt_usrquota),
1685         fsparam_flag    ("prjquota",            Opt_prjquota),
1686         fsparam_flag    ("barrier",             Opt_barrier),
1687         fsparam_u32     ("barrier",             Opt_barrier),
1688         fsparam_flag    ("nobarrier",           Opt_nobarrier),
1689         fsparam_flag    ("i_version",           Opt_removed),
1690         fsparam_flag    ("dax",                 Opt_dax),
1691         fsparam_enum    ("dax",                 Opt_dax_type, ext4_param_dax),
1692         fsparam_u32     ("stripe",              Opt_stripe),
1693         fsparam_flag    ("delalloc",            Opt_delalloc),
1694         fsparam_flag    ("nodelalloc",          Opt_nodelalloc),
1695         fsparam_flag    ("warn_on_error",       Opt_warn_on_error),
1696         fsparam_flag    ("nowarn_on_error",     Opt_nowarn_on_error),
1697         fsparam_u32     ("debug_want_extra_isize",
1698                                                 Opt_debug_want_extra_isize),
1699         fsparam_flag    ("mblk_io_submit",      Opt_removed),
1700         fsparam_flag    ("nomblk_io_submit",    Opt_removed),
1701         fsparam_flag    ("block_validity",      Opt_block_validity),
1702         fsparam_flag    ("noblock_validity",    Opt_noblock_validity),
1703         fsparam_u32     ("inode_readahead_blks",
1704                                                 Opt_inode_readahead_blks),
1705         fsparam_u32     ("journal_ioprio",      Opt_journal_ioprio),
1706         fsparam_u32     ("auto_da_alloc",       Opt_auto_da_alloc),
1707         fsparam_flag    ("auto_da_alloc",       Opt_auto_da_alloc),
1708         fsparam_flag    ("noauto_da_alloc",     Opt_noauto_da_alloc),
1709         fsparam_flag    ("dioread_nolock",      Opt_dioread_nolock),
1710         fsparam_flag    ("nodioread_nolock",    Opt_dioread_lock),
1711         fsparam_flag    ("dioread_lock",        Opt_dioread_lock),
1712         fsparam_flag    ("discard",             Opt_discard),
1713         fsparam_flag    ("nodiscard",           Opt_nodiscard),
1714         fsparam_u32     ("init_itable",         Opt_init_itable),
1715         fsparam_flag    ("init_itable",         Opt_init_itable),
1716         fsparam_flag    ("noinit_itable",       Opt_noinit_itable),
1717 #ifdef CONFIG_EXT4_DEBUG
1718         fsparam_flag    ("fc_debug_force",      Opt_fc_debug_force),
1719         fsparam_u32     ("fc_debug_max_replay", Opt_fc_debug_max_replay),
1720 #endif
1721         fsparam_u32     ("max_dir_size_kb",     Opt_max_dir_size_kb),
1722         fsparam_flag    ("test_dummy_encryption",
1723                                                 Opt_test_dummy_encryption),
1724         fsparam_string  ("test_dummy_encryption",
1725                                                 Opt_test_dummy_encryption),
1726         fsparam_flag    ("inlinecrypt",         Opt_inlinecrypt),
1727         fsparam_flag    ("nombcache",           Opt_nombcache),
1728         fsparam_flag    ("no_mbcache",          Opt_nombcache), /* for backward compatibility */
1729         fsparam_flag    ("prefetch_block_bitmaps",
1730                                                 Opt_removed),
1731         fsparam_flag    ("no_prefetch_block_bitmaps",
1732                                                 Opt_no_prefetch_block_bitmaps),
1733         fsparam_s32     ("mb_optimize_scan",    Opt_mb_optimize_scan),
1734         fsparam_string  ("check",               Opt_removed),   /* mount option from ext2/3 */
1735         fsparam_flag    ("nocheck",             Opt_removed),   /* mount option from ext2/3 */
1736         fsparam_flag    ("reservation",         Opt_removed),   /* mount option from ext2/3 */
1737         fsparam_flag    ("noreservation",       Opt_removed),   /* mount option from ext2/3 */
1738         fsparam_u32     ("journal",             Opt_removed),   /* mount option from ext2/3 */
1739         {}
1740 };
1741
1742 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1743
1744 #define MOPT_SET        0x0001
1745 #define MOPT_CLEAR      0x0002
1746 #define MOPT_NOSUPPORT  0x0004
1747 #define MOPT_EXPLICIT   0x0008
1748 #ifdef CONFIG_QUOTA
1749 #define MOPT_Q          0
1750 #define MOPT_QFMT       0x0010
1751 #else
1752 #define MOPT_Q          MOPT_NOSUPPORT
1753 #define MOPT_QFMT       MOPT_NOSUPPORT
1754 #endif
1755 #define MOPT_NO_EXT2    0x0020
1756 #define MOPT_NO_EXT3    0x0040
1757 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1758 #define MOPT_SKIP       0x0080
1759 #define MOPT_2          0x0100
1760
1761 static const struct mount_opts {
1762         int     token;
1763         int     mount_opt;
1764         int     flags;
1765 } ext4_mount_opts[] = {
1766         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1767         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1768         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1769         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1770         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1771         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1772         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1773          MOPT_EXT4_ONLY | MOPT_SET},
1774         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1775          MOPT_EXT4_ONLY | MOPT_CLEAR},
1776         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1777         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1778         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1779          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1780         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1781          MOPT_EXT4_ONLY | MOPT_CLEAR},
1782         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1783         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1784         {Opt_commit, 0, MOPT_NO_EXT2},
1785         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1786          MOPT_EXT4_ONLY | MOPT_CLEAR},
1787         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1788          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1789         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1790                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1791          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1792         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1793         {Opt_data_err, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_NO_EXT2},
1794         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1795         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1796         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1797         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1798         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1799         {Opt_dax_type, 0, MOPT_EXT4_ONLY},
1800         {Opt_journal_dev, 0, MOPT_NO_EXT2},
1801         {Opt_journal_path, 0, MOPT_NO_EXT2},
1802         {Opt_journal_ioprio, 0, MOPT_NO_EXT2},
1803         {Opt_data, 0, MOPT_NO_EXT2},
1804         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1805 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1806         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1807 #else
1808         {Opt_acl, 0, MOPT_NOSUPPORT},
1809 #endif
1810         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1811         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1812         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1813         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1814                                                         MOPT_SET | MOPT_Q},
1815         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1816                                                         MOPT_SET | MOPT_Q},
1817         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1818                                                         MOPT_SET | MOPT_Q},
1819         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1820                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1821                                                         MOPT_CLEAR | MOPT_Q},
1822         {Opt_usrjquota, 0, MOPT_Q},
1823         {Opt_grpjquota, 0, MOPT_Q},
1824         {Opt_jqfmt, 0, MOPT_QFMT},
1825         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1826         {Opt_no_prefetch_block_bitmaps, EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS,
1827          MOPT_SET},
1828 #ifdef CONFIG_EXT4_DEBUG
1829         {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
1830          MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
1831 #endif
1832         {Opt_err, 0, 0}
1833 };
1834
1835 #if IS_ENABLED(CONFIG_UNICODE)
1836 static const struct ext4_sb_encodings {
1837         __u16 magic;
1838         char *name;
1839         unsigned int version;
1840 } ext4_sb_encoding_map[] = {
1841         {EXT4_ENC_UTF8_12_1, "utf8", UNICODE_AGE(12, 1, 0)},
1842 };
1843
1844 static const struct ext4_sb_encodings *
1845 ext4_sb_read_encoding(const struct ext4_super_block *es)
1846 {
1847         __u16 magic = le16_to_cpu(es->s_encoding);
1848         int i;
1849
1850         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1851                 if (magic == ext4_sb_encoding_map[i].magic)
1852                         return &ext4_sb_encoding_map[i];
1853
1854         return NULL;
1855 }
1856 #endif
1857
1858 #define EXT4_SPEC_JQUOTA                        (1 <<  0)
1859 #define EXT4_SPEC_JQFMT                         (1 <<  1)
1860 #define EXT4_SPEC_DATAJ                         (1 <<  2)
1861 #define EXT4_SPEC_SB_BLOCK                      (1 <<  3)
1862 #define EXT4_SPEC_JOURNAL_DEV                   (1 <<  4)
1863 #define EXT4_SPEC_JOURNAL_IOPRIO                (1 <<  5)
1864 #define EXT4_SPEC_s_want_extra_isize            (1 <<  7)
1865 #define EXT4_SPEC_s_max_batch_time              (1 <<  8)
1866 #define EXT4_SPEC_s_min_batch_time              (1 <<  9)
1867 #define EXT4_SPEC_s_inode_readahead_blks        (1 << 10)
1868 #define EXT4_SPEC_s_li_wait_mult                (1 << 11)
1869 #define EXT4_SPEC_s_max_dir_size_kb             (1 << 12)
1870 #define EXT4_SPEC_s_stripe                      (1 << 13)
1871 #define EXT4_SPEC_s_resuid                      (1 << 14)
1872 #define EXT4_SPEC_s_resgid                      (1 << 15)
1873 #define EXT4_SPEC_s_commit_interval             (1 << 16)
1874 #define EXT4_SPEC_s_fc_debug_max_replay         (1 << 17)
1875 #define EXT4_SPEC_s_sb_block                    (1 << 18)
1876 #define EXT4_SPEC_mb_optimize_scan              (1 << 19)
1877
1878 struct ext4_fs_context {
1879         char            *s_qf_names[EXT4_MAXQUOTAS];
1880         struct fscrypt_dummy_policy dummy_enc_policy;
1881         int             s_jquota_fmt;   /* Format of quota to use */
1882 #ifdef CONFIG_EXT4_DEBUG
1883         int s_fc_debug_max_replay;
1884 #endif
1885         unsigned short  qname_spec;
1886         unsigned long   vals_s_flags;   /* Bits to set in s_flags */
1887         unsigned long   mask_s_flags;   /* Bits changed in s_flags */
1888         unsigned long   journal_devnum;
1889         unsigned long   s_commit_interval;
1890         unsigned long   s_stripe;
1891         unsigned int    s_inode_readahead_blks;
1892         unsigned int    s_want_extra_isize;
1893         unsigned int    s_li_wait_mult;
1894         unsigned int    s_max_dir_size_kb;
1895         unsigned int    journal_ioprio;
1896         unsigned int    vals_s_mount_opt;
1897         unsigned int    mask_s_mount_opt;
1898         unsigned int    vals_s_mount_opt2;
1899         unsigned int    mask_s_mount_opt2;
1900         unsigned long   vals_s_mount_flags;
1901         unsigned long   mask_s_mount_flags;
1902         unsigned int    opt_flags;      /* MOPT flags */
1903         unsigned int    spec;
1904         u32             s_max_batch_time;
1905         u32             s_min_batch_time;
1906         kuid_t          s_resuid;
1907         kgid_t          s_resgid;
1908         ext4_fsblk_t    s_sb_block;
1909 };
1910
1911 static void ext4_fc_free(struct fs_context *fc)
1912 {
1913         struct ext4_fs_context *ctx = fc->fs_private;
1914         int i;
1915
1916         if (!ctx)
1917                 return;
1918
1919         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1920                 kfree(ctx->s_qf_names[i]);
1921
1922         fscrypt_free_dummy_policy(&ctx->dummy_enc_policy);
1923         kfree(ctx);
1924 }
1925
1926 int ext4_init_fs_context(struct fs_context *fc)
1927 {
1928         struct ext4_fs_context *ctx;
1929
1930         ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
1931         if (!ctx)
1932                 return -ENOMEM;
1933
1934         fc->fs_private = ctx;
1935         fc->ops = &ext4_context_ops;
1936
1937         return 0;
1938 }
1939
1940 #ifdef CONFIG_QUOTA
1941 /*
1942  * Note the name of the specified quota file.
1943  */
1944 static int note_qf_name(struct fs_context *fc, int qtype,
1945                        struct fs_parameter *param)
1946 {
1947         struct ext4_fs_context *ctx = fc->fs_private;
1948         char *qname;
1949
1950         if (param->size < 1) {
1951                 ext4_msg(NULL, KERN_ERR, "Missing quota name");
1952                 return -EINVAL;
1953         }
1954         if (strchr(param->string, '/')) {
1955                 ext4_msg(NULL, KERN_ERR,
1956                          "quotafile must be on filesystem root");
1957                 return -EINVAL;
1958         }
1959         if (ctx->s_qf_names[qtype]) {
1960                 if (strcmp(ctx->s_qf_names[qtype], param->string) != 0) {
1961                         ext4_msg(NULL, KERN_ERR,
1962                                  "%s quota file already specified",
1963                                  QTYPE2NAME(qtype));
1964                         return -EINVAL;
1965                 }
1966                 return 0;
1967         }
1968
1969         qname = kmemdup_nul(param->string, param->size, GFP_KERNEL);
1970         if (!qname) {
1971                 ext4_msg(NULL, KERN_ERR,
1972                          "Not enough memory for storing quotafile name");
1973                 return -ENOMEM;
1974         }
1975         ctx->s_qf_names[qtype] = qname;
1976         ctx->qname_spec |= 1 << qtype;
1977         ctx->spec |= EXT4_SPEC_JQUOTA;
1978         return 0;
1979 }
1980
1981 /*
1982  * Clear the name of the specified quota file.
1983  */
1984 static int unnote_qf_name(struct fs_context *fc, int qtype)
1985 {
1986         struct ext4_fs_context *ctx = fc->fs_private;
1987
1988         if (ctx->s_qf_names[qtype])
1989                 kfree(ctx->s_qf_names[qtype]);
1990
1991         ctx->s_qf_names[qtype] = NULL;
1992         ctx->qname_spec |= 1 << qtype;
1993         ctx->spec |= EXT4_SPEC_JQUOTA;
1994         return 0;
1995 }
1996 #endif
1997
1998 static int ext4_parse_test_dummy_encryption(const struct fs_parameter *param,
1999                                             struct ext4_fs_context *ctx)
2000 {
2001         int err;
2002
2003         if (!IS_ENABLED(CONFIG_FS_ENCRYPTION)) {
2004                 ext4_msg(NULL, KERN_WARNING,
2005                          "test_dummy_encryption option not supported");
2006                 return -EINVAL;
2007         }
2008         err = fscrypt_parse_test_dummy_encryption(param,
2009                                                   &ctx->dummy_enc_policy);
2010         if (err == -EINVAL) {
2011                 ext4_msg(NULL, KERN_WARNING,
2012                          "Value of option \"%s\" is unrecognized", param->key);
2013         } else if (err == -EEXIST) {
2014                 ext4_msg(NULL, KERN_WARNING,
2015                          "Conflicting test_dummy_encryption options");
2016                 return -EINVAL;
2017         }
2018         return err;
2019 }
2020
2021 #define EXT4_SET_CTX(name)                                              \
2022 static inline void ctx_set_##name(struct ext4_fs_context *ctx,          \
2023                                   unsigned long flag)                   \
2024 {                                                                       \
2025         ctx->mask_s_##name |= flag;                                     \
2026         ctx->vals_s_##name |= flag;                                     \
2027 }
2028
2029 #define EXT4_CLEAR_CTX(name)                                            \
2030 static inline void ctx_clear_##name(struct ext4_fs_context *ctx,        \
2031                                     unsigned long flag)                 \
2032 {                                                                       \
2033         ctx->mask_s_##name |= flag;                                     \
2034         ctx->vals_s_##name &= ~flag;                                    \
2035 }
2036
2037 #define EXT4_TEST_CTX(name)                                             \
2038 static inline unsigned long                                             \
2039 ctx_test_##name(struct ext4_fs_context *ctx, unsigned long flag)        \
2040 {                                                                       \
2041         return (ctx->vals_s_##name & flag);                             \
2042 }
2043
2044 EXT4_SET_CTX(flags); /* set only */
2045 EXT4_SET_CTX(mount_opt);
2046 EXT4_CLEAR_CTX(mount_opt);
2047 EXT4_TEST_CTX(mount_opt);
2048 EXT4_SET_CTX(mount_opt2);
2049 EXT4_CLEAR_CTX(mount_opt2);
2050 EXT4_TEST_CTX(mount_opt2);
2051
2052 static inline void ctx_set_mount_flag(struct ext4_fs_context *ctx, int bit)
2053 {
2054         set_bit(bit, &ctx->mask_s_mount_flags);
2055         set_bit(bit, &ctx->vals_s_mount_flags);
2056 }
2057
2058 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
2059 {
2060         struct ext4_fs_context *ctx = fc->fs_private;
2061         struct fs_parse_result result;
2062         const struct mount_opts *m;
2063         int is_remount;
2064         kuid_t uid;
2065         kgid_t gid;
2066         int token;
2067
2068         token = fs_parse(fc, ext4_param_specs, param, &result);
2069         if (token < 0)
2070                 return token;
2071         is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2072
2073         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2074                 if (token == m->token)
2075                         break;
2076
2077         ctx->opt_flags |= m->flags;
2078
2079         if (m->flags & MOPT_EXPLICIT) {
2080                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2081                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_EXPLICIT_DELALLOC);
2082                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2083                         ctx_set_mount_opt2(ctx,
2084                                        EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM);
2085                 } else
2086                         return -EINVAL;
2087         }
2088
2089         if (m->flags & MOPT_NOSUPPORT) {
2090                 ext4_msg(NULL, KERN_ERR, "%s option not supported",
2091                          param->key);
2092                 return 0;
2093         }
2094
2095         switch (token) {
2096 #ifdef CONFIG_QUOTA
2097         case Opt_usrjquota:
2098                 if (!*param->string)
2099                         return unnote_qf_name(fc, USRQUOTA);
2100                 else
2101                         return note_qf_name(fc, USRQUOTA, param);
2102         case Opt_grpjquota:
2103                 if (!*param->string)
2104                         return unnote_qf_name(fc, GRPQUOTA);
2105                 else
2106                         return note_qf_name(fc, GRPQUOTA, param);
2107 #endif
2108         case Opt_sb:
2109                 if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2110                         ext4_msg(NULL, KERN_WARNING,
2111                                  "Ignoring %s option on remount", param->key);
2112                 } else {
2113                         ctx->s_sb_block = result.uint_32;
2114                         ctx->spec |= EXT4_SPEC_s_sb_block;
2115                 }
2116                 return 0;
2117         case Opt_removed:
2118                 ext4_msg(NULL, KERN_WARNING, "Ignoring removed %s option",
2119                          param->key);
2120                 return 0;
2121         case Opt_abort:
2122                 ctx_set_mount_flag(ctx, EXT4_MF_FS_ABORTED);
2123                 return 0;
2124         case Opt_inlinecrypt:
2125 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2126                 ctx_set_flags(ctx, SB_INLINECRYPT);
2127 #else
2128                 ext4_msg(NULL, KERN_ERR, "inline encryption not supported");
2129 #endif
2130                 return 0;
2131         case Opt_errors:
2132                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_ERRORS_MASK);
2133                 ctx_set_mount_opt(ctx, result.uint_32);
2134                 return 0;
2135 #ifdef CONFIG_QUOTA
2136         case Opt_jqfmt:
2137                 ctx->s_jquota_fmt = result.uint_32;
2138                 ctx->spec |= EXT4_SPEC_JQFMT;
2139                 return 0;
2140 #endif
2141         case Opt_data:
2142                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2143                 ctx_set_mount_opt(ctx, result.uint_32);
2144                 ctx->spec |= EXT4_SPEC_DATAJ;
2145                 return 0;
2146         case Opt_commit:
2147                 if (result.uint_32 == 0)
2148                         ctx->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE;
2149                 else if (result.uint_32 > INT_MAX / HZ) {
2150                         ext4_msg(NULL, KERN_ERR,
2151                                  "Invalid commit interval %d, "
2152                                  "must be smaller than %d",
2153                                  result.uint_32, INT_MAX / HZ);
2154                         return -EINVAL;
2155                 }
2156                 ctx->s_commit_interval = HZ * result.uint_32;
2157                 ctx->spec |= EXT4_SPEC_s_commit_interval;
2158                 return 0;
2159         case Opt_debug_want_extra_isize:
2160                 if ((result.uint_32 & 1) || (result.uint_32 < 4)) {
2161                         ext4_msg(NULL, KERN_ERR,
2162                                  "Invalid want_extra_isize %d", result.uint_32);
2163                         return -EINVAL;
2164                 }
2165                 ctx->s_want_extra_isize = result.uint_32;
2166                 ctx->spec |= EXT4_SPEC_s_want_extra_isize;
2167                 return 0;
2168         case Opt_max_batch_time:
2169                 ctx->s_max_batch_time = result.uint_32;
2170                 ctx->spec |= EXT4_SPEC_s_max_batch_time;
2171                 return 0;
2172         case Opt_min_batch_time:
2173                 ctx->s_min_batch_time = result.uint_32;
2174                 ctx->spec |= EXT4_SPEC_s_min_batch_time;
2175                 return 0;
2176         case Opt_inode_readahead_blks:
2177                 if (result.uint_32 &&
2178                     (result.uint_32 > (1 << 30) ||
2179                      !is_power_of_2(result.uint_32))) {
2180                         ext4_msg(NULL, KERN_ERR,
2181                                  "EXT4-fs: inode_readahead_blks must be "
2182                                  "0 or a power of 2 smaller than 2^31");
2183                         return -EINVAL;
2184                 }
2185                 ctx->s_inode_readahead_blks = result.uint_32;
2186                 ctx->spec |= EXT4_SPEC_s_inode_readahead_blks;
2187                 return 0;
2188         case Opt_init_itable:
2189                 ctx_set_mount_opt(ctx, EXT4_MOUNT_INIT_INODE_TABLE);
2190                 ctx->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
2191                 if (param->type == fs_value_is_string)
2192                         ctx->s_li_wait_mult = result.uint_32;
2193                 ctx->spec |= EXT4_SPEC_s_li_wait_mult;
2194                 return 0;
2195         case Opt_max_dir_size_kb:
2196                 ctx->s_max_dir_size_kb = result.uint_32;
2197                 ctx->spec |= EXT4_SPEC_s_max_dir_size_kb;
2198                 return 0;
2199 #ifdef CONFIG_EXT4_DEBUG
2200         case Opt_fc_debug_max_replay:
2201                 ctx->s_fc_debug_max_replay = result.uint_32;
2202                 ctx->spec |= EXT4_SPEC_s_fc_debug_max_replay;
2203                 return 0;
2204 #endif
2205         case Opt_stripe:
2206                 ctx->s_stripe = result.uint_32;
2207                 ctx->spec |= EXT4_SPEC_s_stripe;
2208                 return 0;
2209         case Opt_resuid:
2210                 uid = make_kuid(current_user_ns(), result.uint_32);
2211                 if (!uid_valid(uid)) {
2212                         ext4_msg(NULL, KERN_ERR, "Invalid uid value %d",
2213                                  result.uint_32);
2214                         return -EINVAL;
2215                 }
2216                 ctx->s_resuid = uid;
2217                 ctx->spec |= EXT4_SPEC_s_resuid;
2218                 return 0;
2219         case Opt_resgid:
2220                 gid = make_kgid(current_user_ns(), result.uint_32);
2221                 if (!gid_valid(gid)) {
2222                         ext4_msg(NULL, KERN_ERR, "Invalid gid value %d",
2223                                  result.uint_32);
2224                         return -EINVAL;
2225                 }
2226                 ctx->s_resgid = gid;
2227                 ctx->spec |= EXT4_SPEC_s_resgid;
2228                 return 0;
2229         case Opt_journal_dev:
2230                 if (is_remount) {
2231                         ext4_msg(NULL, KERN_ERR,
2232                                  "Cannot specify journal on remount");
2233                         return -EINVAL;
2234                 }
2235                 ctx->journal_devnum = result.uint_32;
2236                 ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2237                 return 0;
2238         case Opt_journal_path:
2239         {
2240                 struct inode *journal_inode;
2241                 struct path path;
2242                 int error;
2243
2244                 if (is_remount) {
2245                         ext4_msg(NULL, KERN_ERR,
2246                                  "Cannot specify journal on remount");
2247                         return -EINVAL;
2248                 }
2249
2250                 error = fs_lookup_param(fc, param, 1, &path);
2251                 if (error) {
2252                         ext4_msg(NULL, KERN_ERR, "error: could not find "
2253                                  "journal device path");
2254                         return -EINVAL;
2255                 }
2256
2257                 journal_inode = d_inode(path.dentry);
2258                 ctx->journal_devnum = new_encode_dev(journal_inode->i_rdev);
2259                 ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2260                 path_put(&path);
2261                 return 0;
2262         }
2263         case Opt_journal_ioprio:
2264                 if (result.uint_32 > 7) {
2265                         ext4_msg(NULL, KERN_ERR, "Invalid journal IO priority"
2266                                  " (must be 0-7)");
2267                         return -EINVAL;
2268                 }
2269                 ctx->journal_ioprio =
2270                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, result.uint_32);
2271                 ctx->spec |= EXT4_SPEC_JOURNAL_IOPRIO;
2272                 return 0;
2273         case Opt_test_dummy_encryption:
2274                 return ext4_parse_test_dummy_encryption(param, ctx);
2275         case Opt_dax:
2276         case Opt_dax_type:
2277 #ifdef CONFIG_FS_DAX
2278         {
2279                 int type = (token == Opt_dax) ?
2280                            Opt_dax : result.uint_32;
2281
2282                 switch (type) {
2283                 case Opt_dax:
2284                 case Opt_dax_always:
2285                         ctx_set_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2286                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2287                         break;
2288                 case Opt_dax_never:
2289                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2290                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2291                         break;
2292                 case Opt_dax_inode:
2293                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2294                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2295                         /* Strictly for printing options */
2296                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE);
2297                         break;
2298                 }
2299                 return 0;
2300         }
2301 #else
2302                 ext4_msg(NULL, KERN_INFO, "dax option not supported");
2303                 return -EINVAL;
2304 #endif
2305         case Opt_data_err:
2306                 if (result.uint_32 == Opt_data_err_abort)
2307                         ctx_set_mount_opt(ctx, m->mount_opt);
2308                 else if (result.uint_32 == Opt_data_err_ignore)
2309                         ctx_clear_mount_opt(ctx, m->mount_opt);
2310                 return 0;
2311         case Opt_mb_optimize_scan:
2312                 if (result.int_32 == 1) {
2313                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2314                         ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2315                 } else if (result.int_32 == 0) {
2316                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2317                         ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2318                 } else {
2319                         ext4_msg(NULL, KERN_WARNING,
2320                                  "mb_optimize_scan should be set to 0 or 1.");
2321                         return -EINVAL;
2322                 }
2323                 return 0;
2324         }
2325
2326         /*
2327          * At this point we should only be getting options requiring MOPT_SET,
2328          * or MOPT_CLEAR. Anything else is a bug
2329          */
2330         if (m->token == Opt_err) {
2331                 ext4_msg(NULL, KERN_WARNING, "buggy handling of option %s",
2332                          param->key);
2333                 WARN_ON(1);
2334                 return -EINVAL;
2335         }
2336
2337         else {
2338                 unsigned int set = 0;
2339
2340                 if ((param->type == fs_value_is_flag) ||
2341                     result.uint_32 > 0)
2342                         set = 1;
2343
2344                 if (m->flags & MOPT_CLEAR)
2345                         set = !set;
2346                 else if (unlikely(!(m->flags & MOPT_SET))) {
2347                         ext4_msg(NULL, KERN_WARNING,
2348                                  "buggy handling of option %s",
2349                                  param->key);
2350                         WARN_ON(1);
2351                         return -EINVAL;
2352                 }
2353                 if (m->flags & MOPT_2) {
2354                         if (set != 0)
2355                                 ctx_set_mount_opt2(ctx, m->mount_opt);
2356                         else
2357                                 ctx_clear_mount_opt2(ctx, m->mount_opt);
2358                 } else {
2359                         if (set != 0)
2360                                 ctx_set_mount_opt(ctx, m->mount_opt);
2361                         else
2362                                 ctx_clear_mount_opt(ctx, m->mount_opt);
2363                 }
2364         }
2365
2366         return 0;
2367 }
2368
2369 static int parse_options(struct fs_context *fc, char *options)
2370 {
2371         struct fs_parameter param;
2372         int ret;
2373         char *key;
2374
2375         if (!options)
2376                 return 0;
2377
2378         while ((key = strsep(&options, ",")) != NULL) {
2379                 if (*key) {
2380                         size_t v_len = 0;
2381                         char *value = strchr(key, '=');
2382
2383                         param.type = fs_value_is_flag;
2384                         param.string = NULL;
2385
2386                         if (value) {
2387                                 if (value == key)
2388                                         continue;
2389
2390                                 *value++ = 0;
2391                                 v_len = strlen(value);
2392                                 param.string = kmemdup_nul(value, v_len,
2393                                                            GFP_KERNEL);
2394                                 if (!param.string)
2395                                         return -ENOMEM;
2396                                 param.type = fs_value_is_string;
2397                         }
2398
2399                         param.key = key;
2400                         param.size = v_len;
2401
2402                         ret = ext4_parse_param(fc, &param);
2403                         if (param.string)
2404                                 kfree(param.string);
2405                         if (ret < 0)
2406                                 return ret;
2407                 }
2408         }
2409
2410         ret = ext4_validate_options(fc);
2411         if (ret < 0)
2412                 return ret;
2413
2414         return 0;
2415 }
2416
2417 static int parse_apply_sb_mount_options(struct super_block *sb,
2418                                         struct ext4_fs_context *m_ctx)
2419 {
2420         struct ext4_sb_info *sbi = EXT4_SB(sb);
2421         char *s_mount_opts = NULL;
2422         struct ext4_fs_context *s_ctx = NULL;
2423         struct fs_context *fc = NULL;
2424         int ret = -ENOMEM;
2425
2426         if (!sbi->s_es->s_mount_opts[0])
2427                 return 0;
2428
2429         s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
2430                                 sizeof(sbi->s_es->s_mount_opts),
2431                                 GFP_KERNEL);
2432         if (!s_mount_opts)
2433                 return ret;
2434
2435         fc = kzalloc(sizeof(struct fs_context), GFP_KERNEL);
2436         if (!fc)
2437                 goto out_free;
2438
2439         s_ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2440         if (!s_ctx)
2441                 goto out_free;
2442
2443         fc->fs_private = s_ctx;
2444         fc->s_fs_info = sbi;
2445
2446         ret = parse_options(fc, s_mount_opts);
2447         if (ret < 0)
2448                 goto parse_failed;
2449
2450         ret = ext4_check_opt_consistency(fc, sb);
2451         if (ret < 0) {
2452 parse_failed:
2453                 ext4_msg(sb, KERN_WARNING,
2454                          "failed to parse options in superblock: %s",
2455                          s_mount_opts);
2456                 ret = 0;
2457                 goto out_free;
2458         }
2459
2460         if (s_ctx->spec & EXT4_SPEC_JOURNAL_DEV)
2461                 m_ctx->journal_devnum = s_ctx->journal_devnum;
2462         if (s_ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)
2463                 m_ctx->journal_ioprio = s_ctx->journal_ioprio;
2464
2465         ext4_apply_options(fc, sb);
2466         ret = 0;
2467
2468 out_free:
2469         if (fc) {
2470                 ext4_fc_free(fc);
2471                 kfree(fc);
2472         }
2473         kfree(s_mount_opts);
2474         return ret;
2475 }
2476
2477 static void ext4_apply_quota_options(struct fs_context *fc,
2478                                      struct super_block *sb)
2479 {
2480 #ifdef CONFIG_QUOTA
2481         bool quota_feature = ext4_has_feature_quota(sb);
2482         struct ext4_fs_context *ctx = fc->fs_private;
2483         struct ext4_sb_info *sbi = EXT4_SB(sb);
2484         char *qname;
2485         int i;
2486
2487         if (quota_feature)
2488                 return;
2489
2490         if (ctx->spec & EXT4_SPEC_JQUOTA) {
2491                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2492                         if (!(ctx->qname_spec & (1 << i)))
2493                                 continue;
2494
2495                         qname = ctx->s_qf_names[i]; /* May be NULL */
2496                         if (qname)
2497                                 set_opt(sb, QUOTA);
2498                         ctx->s_qf_names[i] = NULL;
2499                         qname = rcu_replace_pointer(sbi->s_qf_names[i], qname,
2500                                                 lockdep_is_held(&sb->s_umount));
2501                         if (qname)
2502                                 kfree_rcu(qname);
2503                 }
2504         }
2505
2506         if (ctx->spec & EXT4_SPEC_JQFMT)
2507                 sbi->s_jquota_fmt = ctx->s_jquota_fmt;
2508 #endif
2509 }
2510
2511 /*
2512  * Check quota settings consistency.
2513  */
2514 static int ext4_check_quota_consistency(struct fs_context *fc,
2515                                         struct super_block *sb)
2516 {
2517 #ifdef CONFIG_QUOTA
2518         struct ext4_fs_context *ctx = fc->fs_private;
2519         struct ext4_sb_info *sbi = EXT4_SB(sb);
2520         bool quota_feature = ext4_has_feature_quota(sb);
2521         bool quota_loaded = sb_any_quota_loaded(sb);
2522         bool usr_qf_name, grp_qf_name, usrquota, grpquota;
2523         int quota_flags, i;
2524
2525         /*
2526          * We do the test below only for project quotas. 'usrquota' and
2527          * 'grpquota' mount options are allowed even without quota feature
2528          * to support legacy quotas in quota files.
2529          */
2530         if (ctx_test_mount_opt(ctx, EXT4_MOUNT_PRJQUOTA) &&
2531             !ext4_has_feature_project(sb)) {
2532                 ext4_msg(NULL, KERN_ERR, "Project quota feature not enabled. "
2533                          "Cannot enable project quota enforcement.");
2534                 return -EINVAL;
2535         }
2536
2537         quota_flags = EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2538                       EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA;
2539         if (quota_loaded &&
2540             ctx->mask_s_mount_opt & quota_flags &&
2541             !ctx_test_mount_opt(ctx, quota_flags))
2542                 goto err_quota_change;
2543
2544         if (ctx->spec & EXT4_SPEC_JQUOTA) {
2545
2546                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2547                         if (!(ctx->qname_spec & (1 << i)))
2548                                 continue;
2549
2550                         if (quota_loaded &&
2551                             !!sbi->s_qf_names[i] != !!ctx->s_qf_names[i])
2552                                 goto err_jquota_change;
2553
2554                         if (sbi->s_qf_names[i] && ctx->s_qf_names[i] &&
2555                             strcmp(get_qf_name(sb, sbi, i),
2556                                    ctx->s_qf_names[i]) != 0)
2557                                 goto err_jquota_specified;
2558                 }
2559
2560                 if (quota_feature) {
2561                         ext4_msg(NULL, KERN_INFO,
2562                                  "Journaled quota options ignored when "
2563                                  "QUOTA feature is enabled");
2564                         return 0;
2565                 }
2566         }
2567
2568         if (ctx->spec & EXT4_SPEC_JQFMT) {
2569                 if (sbi->s_jquota_fmt != ctx->s_jquota_fmt && quota_loaded)
2570                         goto err_jquota_change;
2571                 if (quota_feature) {
2572                         ext4_msg(NULL, KERN_INFO, "Quota format mount options "
2573                                  "ignored when QUOTA feature is enabled");
2574                         return 0;
2575                 }
2576         }
2577
2578         /* Make sure we don't mix old and new quota format */
2579         usr_qf_name = (get_qf_name(sb, sbi, USRQUOTA) ||
2580                        ctx->s_qf_names[USRQUOTA]);
2581         grp_qf_name = (get_qf_name(sb, sbi, GRPQUOTA) ||
2582                        ctx->s_qf_names[GRPQUOTA]);
2583
2584         usrquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2585                     test_opt(sb, USRQUOTA));
2586
2587         grpquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) ||
2588                     test_opt(sb, GRPQUOTA));
2589
2590         if (usr_qf_name) {
2591                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2592                 usrquota = false;
2593         }
2594         if (grp_qf_name) {
2595                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2596                 grpquota = false;
2597         }
2598
2599         if (usr_qf_name || grp_qf_name) {
2600                 if (usrquota || grpquota) {
2601                         ext4_msg(NULL, KERN_ERR, "old and new quota "
2602                                  "format mixing");
2603                         return -EINVAL;
2604                 }
2605
2606                 if (!(ctx->spec & EXT4_SPEC_JQFMT || sbi->s_jquota_fmt)) {
2607                         ext4_msg(NULL, KERN_ERR, "journaled quota format "
2608                                  "not specified");
2609                         return -EINVAL;
2610                 }
2611         }
2612
2613         return 0;
2614
2615 err_quota_change:
2616         ext4_msg(NULL, KERN_ERR,
2617                  "Cannot change quota options when quota turned on");
2618         return -EINVAL;
2619 err_jquota_change:
2620         ext4_msg(NULL, KERN_ERR, "Cannot change journaled quota "
2621                  "options when quota turned on");
2622         return -EINVAL;
2623 err_jquota_specified:
2624         ext4_msg(NULL, KERN_ERR, "%s quota file already specified",
2625                  QTYPE2NAME(i));
2626         return -EINVAL;
2627 #else
2628         return 0;
2629 #endif
2630 }
2631
2632 static int ext4_check_test_dummy_encryption(const struct fs_context *fc,
2633                                             struct super_block *sb)
2634 {
2635         const struct ext4_fs_context *ctx = fc->fs_private;
2636         const struct ext4_sb_info *sbi = EXT4_SB(sb);
2637         int err;
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         /*
2671          * fscrypt_add_test_dummy_key() technically changes the super_block, so
2672          * technically it should be delayed until ext4_apply_options() like the
2673          * other changes.  But since we never get here for remounts (see above),
2674          * and this is the last chance to report errors, we do it here.
2675          */
2676         err = fscrypt_add_test_dummy_key(sb, &ctx->dummy_enc_policy);
2677         if (err)
2678                 ext4_msg(NULL, KERN_WARNING,
2679                          "Error adding test dummy encryption key [%d]", err);
2680         return err;
2681 }
2682
2683 static void ext4_apply_test_dummy_encryption(struct ext4_fs_context *ctx,
2684                                              struct super_block *sb)
2685 {
2686         if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy) ||
2687             /* if already set, it was already verified to be the same */
2688             fscrypt_is_dummy_policy_set(&EXT4_SB(sb)->s_dummy_enc_policy))
2689                 return;
2690         EXT4_SB(sb)->s_dummy_enc_policy = ctx->dummy_enc_policy;
2691         memset(&ctx->dummy_enc_policy, 0, sizeof(ctx->dummy_enc_policy));
2692         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2693 }
2694
2695 static int ext4_check_opt_consistency(struct fs_context *fc,
2696                                       struct super_block *sb)
2697 {
2698         struct ext4_fs_context *ctx = fc->fs_private;
2699         struct ext4_sb_info *sbi = fc->s_fs_info;
2700         int is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2701         int err;
2702
2703         if ((ctx->opt_flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2704                 ext4_msg(NULL, KERN_ERR,
2705                          "Mount option(s) incompatible with ext2");
2706                 return -EINVAL;
2707         }
2708         if ((ctx->opt_flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2709                 ext4_msg(NULL, KERN_ERR,
2710                          "Mount option(s) incompatible with ext3");
2711                 return -EINVAL;
2712         }
2713
2714         if (ctx->s_want_extra_isize >
2715             (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE)) {
2716                 ext4_msg(NULL, KERN_ERR,
2717                          "Invalid want_extra_isize %d",
2718                          ctx->s_want_extra_isize);
2719                 return -EINVAL;
2720         }
2721
2722         if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DIOREAD_NOLOCK)) {
2723                 int blocksize =
2724                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2725                 if (blocksize < PAGE_SIZE)
2726                         ext4_msg(NULL, KERN_WARNING, "Warning: mounting with an "
2727                                  "experimental mount option 'dioread_nolock' "
2728                                  "for blocksize < PAGE_SIZE");
2729         }
2730
2731         err = ext4_check_test_dummy_encryption(fc, sb);
2732         if (err)
2733                 return err;
2734
2735         if ((ctx->spec & EXT4_SPEC_DATAJ) && is_remount) {
2736                 if (!sbi->s_journal) {
2737                         ext4_msg(NULL, KERN_WARNING,
2738                                  "Remounting file system with no journal "
2739                                  "so ignoring journalled data option");
2740                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2741                 } else if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS) !=
2742                            test_opt(sb, DATA_FLAGS)) {
2743                         ext4_msg(NULL, KERN_ERR, "Cannot change data mode "
2744                                  "on remount");
2745                         return -EINVAL;
2746                 }
2747         }
2748
2749         if (is_remount) {
2750                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2751                     (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2752                         ext4_msg(NULL, KERN_ERR, "can't mount with "
2753                                  "both data=journal and dax");
2754                         return -EINVAL;
2755                 }
2756
2757                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2758                     (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2759                      (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2760 fail_dax_change_remount:
2761                         ext4_msg(NULL, KERN_ERR, "can't change "
2762                                  "dax mount option while remounting");
2763                         return -EINVAL;
2764                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER) &&
2765                          (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2766                           (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS))) {
2767                         goto fail_dax_change_remount;
2768                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE) &&
2769                            ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2770                             (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2771                             !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE))) {
2772                         goto fail_dax_change_remount;
2773                 }
2774         }
2775
2776         return ext4_check_quota_consistency(fc, sb);
2777 }
2778
2779 static void ext4_apply_options(struct fs_context *fc, struct super_block *sb)
2780 {
2781         struct ext4_fs_context *ctx = fc->fs_private;
2782         struct ext4_sb_info *sbi = fc->s_fs_info;
2783
2784         sbi->s_mount_opt &= ~ctx->mask_s_mount_opt;
2785         sbi->s_mount_opt |= ctx->vals_s_mount_opt;
2786         sbi->s_mount_opt2 &= ~ctx->mask_s_mount_opt2;
2787         sbi->s_mount_opt2 |= ctx->vals_s_mount_opt2;
2788         sbi->s_mount_flags &= ~ctx->mask_s_mount_flags;
2789         sbi->s_mount_flags |= ctx->vals_s_mount_flags;
2790         sb->s_flags &= ~ctx->mask_s_flags;
2791         sb->s_flags |= ctx->vals_s_flags;
2792
2793 #define APPLY(X) ({ if (ctx->spec & EXT4_SPEC_##X) sbi->X = ctx->X; })
2794         APPLY(s_commit_interval);
2795         APPLY(s_stripe);
2796         APPLY(s_max_batch_time);
2797         APPLY(s_min_batch_time);
2798         APPLY(s_want_extra_isize);
2799         APPLY(s_inode_readahead_blks);
2800         APPLY(s_max_dir_size_kb);
2801         APPLY(s_li_wait_mult);
2802         APPLY(s_resgid);
2803         APPLY(s_resuid);
2804
2805 #ifdef CONFIG_EXT4_DEBUG
2806         APPLY(s_fc_debug_max_replay);
2807 #endif
2808
2809         ext4_apply_quota_options(fc, sb);
2810         ext4_apply_test_dummy_encryption(ctx, sb);
2811 }
2812
2813
2814 static int ext4_validate_options(struct fs_context *fc)
2815 {
2816 #ifdef CONFIG_QUOTA
2817         struct ext4_fs_context *ctx = fc->fs_private;
2818         char *usr_qf_name, *grp_qf_name;
2819
2820         usr_qf_name = ctx->s_qf_names[USRQUOTA];
2821         grp_qf_name = ctx->s_qf_names[GRPQUOTA];
2822
2823         if (usr_qf_name || grp_qf_name) {
2824                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) && usr_qf_name)
2825                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2826
2827                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) && grp_qf_name)
2828                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2829
2830                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2831                     ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA)) {
2832                         ext4_msg(NULL, KERN_ERR, "old and new quota "
2833                                  "format mixing");
2834                         return -EINVAL;
2835                 }
2836         }
2837 #endif
2838         return 1;
2839 }
2840
2841 static inline void ext4_show_quota_options(struct seq_file *seq,
2842                                            struct super_block *sb)
2843 {
2844 #if defined(CONFIG_QUOTA)
2845         struct ext4_sb_info *sbi = EXT4_SB(sb);
2846         char *usr_qf_name, *grp_qf_name;
2847
2848         if (sbi->s_jquota_fmt) {
2849                 char *fmtname = "";
2850
2851                 switch (sbi->s_jquota_fmt) {
2852                 case QFMT_VFS_OLD:
2853                         fmtname = "vfsold";
2854                         break;
2855                 case QFMT_VFS_V0:
2856                         fmtname = "vfsv0";
2857                         break;
2858                 case QFMT_VFS_V1:
2859                         fmtname = "vfsv1";
2860                         break;
2861                 }
2862                 seq_printf(seq, ",jqfmt=%s", fmtname);
2863         }
2864
2865         rcu_read_lock();
2866         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2867         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2868         if (usr_qf_name)
2869                 seq_show_option(seq, "usrjquota", usr_qf_name);
2870         if (grp_qf_name)
2871                 seq_show_option(seq, "grpjquota", grp_qf_name);
2872         rcu_read_unlock();
2873 #endif
2874 }
2875
2876 static const char *token2str(int token)
2877 {
2878         const struct fs_parameter_spec *spec;
2879
2880         for (spec = ext4_param_specs; spec->name != NULL; spec++)
2881                 if (spec->opt == token && !spec->type)
2882                         break;
2883         return spec->name;
2884 }
2885
2886 /*
2887  * Show an option if
2888  *  - it's set to a non-default value OR
2889  *  - if the per-sb default is different from the global default
2890  */
2891 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2892                               int nodefs)
2893 {
2894         struct ext4_sb_info *sbi = EXT4_SB(sb);
2895         struct ext4_super_block *es = sbi->s_es;
2896         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2897         const struct mount_opts *m;
2898         char sep = nodefs ? '\n' : ',';
2899
2900 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2901 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2902
2903         if (sbi->s_sb_block != 1)
2904                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2905
2906         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2907                 int want_set = m->flags & MOPT_SET;
2908                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2909                     m->flags & MOPT_SKIP)
2910                         continue;
2911                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2912                         continue; /* skip if same as the default */
2913                 if ((want_set &&
2914                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2915                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2916                         continue; /* select Opt_noFoo vs Opt_Foo */
2917                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2918         }
2919
2920         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2921             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2922                 SEQ_OPTS_PRINT("resuid=%u",
2923                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2924         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2925             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2926                 SEQ_OPTS_PRINT("resgid=%u",
2927                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2928         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2929         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2930                 SEQ_OPTS_PUTS("errors=remount-ro");
2931         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2932                 SEQ_OPTS_PUTS("errors=continue");
2933         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2934                 SEQ_OPTS_PUTS("errors=panic");
2935         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2936                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2937         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2938                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2939         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2940                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2941         if (nodefs || sbi->s_stripe)
2942                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2943         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2944                         (sbi->s_mount_opt ^ def_mount_opt)) {
2945                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2946                         SEQ_OPTS_PUTS("data=journal");
2947                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2948                         SEQ_OPTS_PUTS("data=ordered");
2949                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2950                         SEQ_OPTS_PUTS("data=writeback");
2951         }
2952         if (nodefs ||
2953             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2954                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2955                                sbi->s_inode_readahead_blks);
2956
2957         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2958                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2959                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2960         if (nodefs || sbi->s_max_dir_size_kb)
2961                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2962         if (test_opt(sb, DATA_ERR_ABORT))
2963                 SEQ_OPTS_PUTS("data_err=abort");
2964
2965         fscrypt_show_test_dummy_encryption(seq, sep, sb);
2966
2967         if (sb->s_flags & SB_INLINECRYPT)
2968                 SEQ_OPTS_PUTS("inlinecrypt");
2969
2970         if (test_opt(sb, DAX_ALWAYS)) {
2971                 if (IS_EXT2_SB(sb))
2972                         SEQ_OPTS_PUTS("dax");
2973                 else
2974                         SEQ_OPTS_PUTS("dax=always");
2975         } else if (test_opt2(sb, DAX_NEVER)) {
2976                 SEQ_OPTS_PUTS("dax=never");
2977         } else if (test_opt2(sb, DAX_INODE)) {
2978                 SEQ_OPTS_PUTS("dax=inode");
2979         }
2980
2981         if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
2982                         !test_opt2(sb, MB_OPTIMIZE_SCAN)) {
2983                 SEQ_OPTS_PUTS("mb_optimize_scan=0");
2984         } else if (sbi->s_groups_count < MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
2985                         test_opt2(sb, MB_OPTIMIZE_SCAN)) {
2986                 SEQ_OPTS_PUTS("mb_optimize_scan=1");
2987         }
2988
2989         ext4_show_quota_options(seq, sb);
2990         return 0;
2991 }
2992
2993 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2994 {
2995         return _ext4_show_options(seq, root->d_sb, 0);
2996 }
2997
2998 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2999 {
3000         struct super_block *sb = seq->private;
3001         int rc;
3002
3003         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
3004         rc = _ext4_show_options(seq, sb, 1);
3005         seq_puts(seq, "\n");
3006         return rc;
3007 }
3008
3009 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
3010                             int read_only)
3011 {
3012         struct ext4_sb_info *sbi = EXT4_SB(sb);
3013         int err = 0;
3014
3015         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
3016                 ext4_msg(sb, KERN_ERR, "revision level too high, "
3017                          "forcing read-only mode");
3018                 err = -EROFS;
3019                 goto done;
3020         }
3021         if (read_only)
3022                 goto done;
3023         if (!(sbi->s_mount_state & EXT4_VALID_FS))
3024                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
3025                          "running e2fsck is recommended");
3026         else if (sbi->s_mount_state & EXT4_ERROR_FS)
3027                 ext4_msg(sb, KERN_WARNING,
3028                          "warning: mounting fs with errors, "
3029                          "running e2fsck is recommended");
3030         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
3031                  le16_to_cpu(es->s_mnt_count) >=
3032                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
3033                 ext4_msg(sb, KERN_WARNING,
3034                          "warning: maximal mount count reached, "
3035                          "running e2fsck is recommended");
3036         else if (le32_to_cpu(es->s_checkinterval) &&
3037                  (ext4_get_tstamp(es, s_lastcheck) +
3038                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
3039                 ext4_msg(sb, KERN_WARNING,
3040                          "warning: checktime reached, "
3041                          "running e2fsck is recommended");
3042         if (!sbi->s_journal)
3043                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
3044         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
3045                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
3046         le16_add_cpu(&es->s_mnt_count, 1);
3047         ext4_update_tstamp(es, s_mtime);
3048         if (sbi->s_journal) {
3049                 ext4_set_feature_journal_needs_recovery(sb);
3050                 if (ext4_has_feature_orphan_file(sb))
3051                         ext4_set_feature_orphan_present(sb);
3052         }
3053
3054         err = ext4_commit_super(sb);
3055 done:
3056         if (test_opt(sb, DEBUG))
3057                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
3058                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
3059                         sb->s_blocksize,
3060                         sbi->s_groups_count,
3061                         EXT4_BLOCKS_PER_GROUP(sb),
3062                         EXT4_INODES_PER_GROUP(sb),
3063                         sbi->s_mount_opt, sbi->s_mount_opt2);
3064         return err;
3065 }
3066
3067 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
3068 {
3069         struct ext4_sb_info *sbi = EXT4_SB(sb);
3070         struct flex_groups **old_groups, **new_groups;
3071         int size, i, j;
3072
3073         if (!sbi->s_log_groups_per_flex)
3074                 return 0;
3075
3076         size = ext4_flex_group(sbi, ngroup - 1) + 1;
3077         if (size <= sbi->s_flex_groups_allocated)
3078                 return 0;
3079
3080         new_groups = kvzalloc(roundup_pow_of_two(size *
3081                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
3082         if (!new_groups) {
3083                 ext4_msg(sb, KERN_ERR,
3084                          "not enough memory for %d flex group pointers", size);
3085                 return -ENOMEM;
3086         }
3087         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
3088                 new_groups[i] = kvzalloc(roundup_pow_of_two(
3089                                          sizeof(struct flex_groups)),
3090                                          GFP_KERNEL);
3091                 if (!new_groups[i]) {
3092                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
3093                                 kvfree(new_groups[j]);
3094                         kvfree(new_groups);
3095                         ext4_msg(sb, KERN_ERR,
3096                                  "not enough memory for %d flex groups", size);
3097                         return -ENOMEM;
3098                 }
3099         }
3100         rcu_read_lock();
3101         old_groups = rcu_dereference(sbi->s_flex_groups);
3102         if (old_groups)
3103                 memcpy(new_groups, old_groups,
3104                        (sbi->s_flex_groups_allocated *
3105                         sizeof(struct flex_groups *)));
3106         rcu_read_unlock();
3107         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
3108         sbi->s_flex_groups_allocated = size;
3109         if (old_groups)
3110                 ext4_kvfree_array_rcu(old_groups);
3111         return 0;
3112 }
3113
3114 static int ext4_fill_flex_info(struct super_block *sb)
3115 {
3116         struct ext4_sb_info *sbi = EXT4_SB(sb);
3117         struct ext4_group_desc *gdp = NULL;
3118         struct flex_groups *fg;
3119         ext4_group_t flex_group;
3120         int i, err;
3121
3122         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
3123         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
3124                 sbi->s_log_groups_per_flex = 0;
3125                 return 1;
3126         }
3127
3128         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
3129         if (err)
3130                 goto failed;
3131
3132         for (i = 0; i < sbi->s_groups_count; i++) {
3133                 gdp = ext4_get_group_desc(sb, i, NULL);
3134
3135                 flex_group = ext4_flex_group(sbi, i);
3136                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
3137                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
3138                 atomic64_add(ext4_free_group_clusters(sb, gdp),
3139                              &fg->free_clusters);
3140                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
3141         }
3142
3143         return 1;
3144 failed:
3145         return 0;
3146 }
3147
3148 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
3149                                    struct ext4_group_desc *gdp)
3150 {
3151         int offset = offsetof(struct ext4_group_desc, bg_checksum);
3152         __u16 crc = 0;
3153         __le32 le_group = cpu_to_le32(block_group);
3154         struct ext4_sb_info *sbi = EXT4_SB(sb);
3155
3156         if (ext4_has_metadata_csum(sbi->s_sb)) {
3157                 /* Use new metadata_csum algorithm */
3158                 __u32 csum32;
3159                 __u16 dummy_csum = 0;
3160
3161                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
3162                                      sizeof(le_group));
3163                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
3164                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
3165                                      sizeof(dummy_csum));
3166                 offset += sizeof(dummy_csum);
3167                 if (offset < sbi->s_desc_size)
3168                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
3169                                              sbi->s_desc_size - offset);
3170
3171                 crc = csum32 & 0xFFFF;
3172                 goto out;
3173         }
3174
3175         /* old crc16 code */
3176         if (!ext4_has_feature_gdt_csum(sb))
3177                 return 0;
3178
3179         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
3180         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
3181         crc = crc16(crc, (__u8 *)gdp, offset);
3182         offset += sizeof(gdp->bg_checksum); /* skip checksum */
3183         /* for checksum of struct ext4_group_desc do the rest...*/
3184         if (ext4_has_feature_64bit(sb) &&
3185             offset < le16_to_cpu(sbi->s_es->s_desc_size))
3186                 crc = crc16(crc, (__u8 *)gdp + offset,
3187                             le16_to_cpu(sbi->s_es->s_desc_size) -
3188                                 offset);
3189
3190 out:
3191         return cpu_to_le16(crc);
3192 }
3193
3194 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
3195                                 struct ext4_group_desc *gdp)
3196 {
3197         if (ext4_has_group_desc_csum(sb) &&
3198             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
3199                 return 0;
3200
3201         return 1;
3202 }
3203
3204 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
3205                               struct ext4_group_desc *gdp)
3206 {
3207         if (!ext4_has_group_desc_csum(sb))
3208                 return;
3209         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
3210 }
3211
3212 /* Called at mount-time, super-block is locked */
3213 static int ext4_check_descriptors(struct super_block *sb,
3214                                   ext4_fsblk_t sb_block,
3215                                   ext4_group_t *first_not_zeroed)
3216 {
3217         struct ext4_sb_info *sbi = EXT4_SB(sb);
3218         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
3219         ext4_fsblk_t last_block;
3220         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
3221         ext4_fsblk_t block_bitmap;
3222         ext4_fsblk_t inode_bitmap;
3223         ext4_fsblk_t inode_table;
3224         int flexbg_flag = 0;
3225         ext4_group_t i, grp = sbi->s_groups_count;
3226
3227         if (ext4_has_feature_flex_bg(sb))
3228                 flexbg_flag = 1;
3229
3230         ext4_debug("Checking group descriptors");
3231
3232         for (i = 0; i < sbi->s_groups_count; i++) {
3233                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
3234
3235                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
3236                         last_block = ext4_blocks_count(sbi->s_es) - 1;
3237                 else
3238                         last_block = first_block +
3239                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
3240
3241                 if ((grp == sbi->s_groups_count) &&
3242                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3243                         grp = i;
3244
3245                 block_bitmap = ext4_block_bitmap(sb, gdp);
3246                 if (block_bitmap == sb_block) {
3247                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3248                                  "Block bitmap for group %u overlaps "
3249                                  "superblock", i);
3250                         if (!sb_rdonly(sb))
3251                                 return 0;
3252                 }
3253                 if (block_bitmap >= sb_block + 1 &&
3254                     block_bitmap <= last_bg_block) {
3255                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3256                                  "Block bitmap for group %u overlaps "
3257                                  "block group descriptors", i);
3258                         if (!sb_rdonly(sb))
3259                                 return 0;
3260                 }
3261                 if (block_bitmap < first_block || block_bitmap > last_block) {
3262                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3263                                "Block bitmap for group %u not in group "
3264                                "(block %llu)!", i, block_bitmap);
3265                         return 0;
3266                 }
3267                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
3268                 if (inode_bitmap == sb_block) {
3269                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3270                                  "Inode bitmap for group %u overlaps "
3271                                  "superblock", i);
3272                         if (!sb_rdonly(sb))
3273                                 return 0;
3274                 }
3275                 if (inode_bitmap >= sb_block + 1 &&
3276                     inode_bitmap <= last_bg_block) {
3277                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3278                                  "Inode bitmap for group %u overlaps "
3279                                  "block group descriptors", i);
3280                         if (!sb_rdonly(sb))
3281                                 return 0;
3282                 }
3283                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
3284                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3285                                "Inode bitmap for group %u not in group "
3286                                "(block %llu)!", i, inode_bitmap);
3287                         return 0;
3288                 }
3289                 inode_table = ext4_inode_table(sb, gdp);
3290                 if (inode_table == sb_block) {
3291                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3292                                  "Inode table for group %u overlaps "
3293                                  "superblock", i);
3294                         if (!sb_rdonly(sb))
3295                                 return 0;
3296                 }
3297                 if (inode_table >= sb_block + 1 &&
3298                     inode_table <= last_bg_block) {
3299                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3300                                  "Inode table for group %u overlaps "
3301                                  "block group descriptors", i);
3302                         if (!sb_rdonly(sb))
3303                                 return 0;
3304                 }
3305                 if (inode_table < first_block ||
3306                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
3307                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3308                                "Inode table for group %u not in group "
3309                                "(block %llu)!", i, inode_table);
3310                         return 0;
3311                 }
3312                 ext4_lock_group(sb, i);
3313                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
3314                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3315                                  "Checksum for group %u failed (%u!=%u)",
3316                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
3317                                      gdp)), le16_to_cpu(gdp->bg_checksum));
3318                         if (!sb_rdonly(sb)) {
3319                                 ext4_unlock_group(sb, i);
3320                                 return 0;
3321                         }
3322                 }
3323                 ext4_unlock_group(sb, i);
3324                 if (!flexbg_flag)
3325                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
3326         }
3327         if (NULL != first_not_zeroed)
3328                 *first_not_zeroed = grp;
3329         return 1;
3330 }
3331
3332 /*
3333  * Maximal extent format file size.
3334  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3335  * extent format containers, within a sector_t, and within i_blocks
3336  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3337  * so that won't be a limiting factor.
3338  *
3339  * However there is other limiting factor. We do store extents in the form
3340  * of starting block and length, hence the resulting length of the extent
3341  * covering maximum file size must fit into on-disk format containers as
3342  * well. Given that length is always by 1 unit bigger than max unit (because
3343  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3344  *
3345  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3346  */
3347 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3348 {
3349         loff_t res;
3350         loff_t upper_limit = MAX_LFS_FILESIZE;
3351
3352         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3353
3354         if (!has_huge_files) {
3355                 upper_limit = (1LL << 32) - 1;
3356
3357                 /* total blocks in file system block size */
3358                 upper_limit >>= (blkbits - 9);
3359                 upper_limit <<= blkbits;
3360         }
3361
3362         /*
3363          * 32-bit extent-start container, ee_block. We lower the maxbytes
3364          * by one fs block, so ee_len can cover the extent of maximum file
3365          * size
3366          */
3367         res = (1LL << 32) - 1;
3368         res <<= blkbits;
3369
3370         /* Sanity check against vm- & vfs- imposed limits */
3371         if (res > upper_limit)
3372                 res = upper_limit;
3373
3374         return res;
3375 }
3376
3377 /*
3378  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3379  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3380  * We need to be 1 filesystem block less than the 2^48 sector limit.
3381  */
3382 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3383 {
3384         loff_t upper_limit, res = EXT4_NDIR_BLOCKS;
3385         int meta_blocks;
3386         unsigned int ppb = 1 << (bits - 2);
3387
3388         /*
3389          * This is calculated to be the largest file size for a dense, block
3390          * mapped file such that the file's total number of 512-byte sectors,
3391          * including data and all indirect blocks, does not exceed (2^48 - 1).
3392          *
3393          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3394          * number of 512-byte sectors of the file.
3395          */
3396         if (!has_huge_files) {
3397                 /*
3398                  * !has_huge_files or implies that the inode i_block field
3399                  * represents total file blocks in 2^32 512-byte sectors ==
3400                  * size of vfs inode i_blocks * 8
3401                  */
3402                 upper_limit = (1LL << 32) - 1;
3403
3404                 /* total blocks in file system block size */
3405                 upper_limit >>= (bits - 9);
3406
3407         } else {
3408                 /*
3409                  * We use 48 bit ext4_inode i_blocks
3410                  * With EXT4_HUGE_FILE_FL set the i_blocks
3411                  * represent total number of blocks in
3412                  * file system block size
3413                  */
3414                 upper_limit = (1LL << 48) - 1;
3415
3416         }
3417
3418         /* Compute how many blocks we can address by block tree */
3419         res += ppb;
3420         res += ppb * ppb;
3421         res += ((loff_t)ppb) * ppb * ppb;
3422         /* Compute how many metadata blocks are needed */
3423         meta_blocks = 1;
3424         meta_blocks += 1 + ppb;
3425         meta_blocks += 1 + ppb + ppb * ppb;
3426         /* Does block tree limit file size? */
3427         if (res + meta_blocks <= upper_limit)
3428                 goto check_lfs;
3429
3430         res = upper_limit;
3431         /* How many metadata blocks are needed for addressing upper_limit? */
3432         upper_limit -= EXT4_NDIR_BLOCKS;
3433         /* indirect blocks */
3434         meta_blocks = 1;
3435         upper_limit -= ppb;
3436         /* double indirect blocks */
3437         if (upper_limit < ppb * ppb) {
3438                 meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb);
3439                 res -= meta_blocks;
3440                 goto check_lfs;
3441         }
3442         meta_blocks += 1 + ppb;
3443         upper_limit -= ppb * ppb;
3444         /* tripple indirect blocks for the rest */
3445         meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb) +
3446                 DIV_ROUND_UP_ULL(upper_limit, ppb*ppb);
3447         res -= meta_blocks;
3448 check_lfs:
3449         res <<= bits;
3450         if (res > MAX_LFS_FILESIZE)
3451                 res = MAX_LFS_FILESIZE;
3452
3453         return res;
3454 }
3455
3456 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3457                                    ext4_fsblk_t logical_sb_block, int nr)
3458 {
3459         struct ext4_sb_info *sbi = EXT4_SB(sb);
3460         ext4_group_t bg, first_meta_bg;
3461         int has_super = 0;
3462
3463         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3464
3465         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3466                 return logical_sb_block + nr + 1;
3467         bg = sbi->s_desc_per_block * nr;
3468         if (ext4_bg_has_super(sb, bg))
3469                 has_super = 1;
3470
3471         /*
3472          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3473          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3474          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3475          * compensate.
3476          */
3477         if (sb->s_blocksize == 1024 && nr == 0 &&
3478             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3479                 has_super++;
3480
3481         return (has_super + ext4_group_first_block_no(sb, bg));
3482 }
3483
3484 /**
3485  * ext4_get_stripe_size: Get the stripe size.
3486  * @sbi: In memory super block info
3487  *
3488  * If we have specified it via mount option, then
3489  * use the mount option value. If the value specified at mount time is
3490  * greater than the blocks per group use the super block value.
3491  * If the super block value is greater than blocks per group return 0.
3492  * Allocator needs it be less than blocks per group.
3493  *
3494  */
3495 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3496 {
3497         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3498         unsigned long stripe_width =
3499                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3500         int ret;
3501
3502         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3503                 ret = sbi->s_stripe;
3504         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3505                 ret = stripe_width;
3506         else if (stride && stride <= sbi->s_blocks_per_group)
3507                 ret = stride;
3508         else
3509                 ret = 0;
3510
3511         /*
3512          * If the stripe width is 1, this makes no sense and
3513          * we set it to 0 to turn off stripe handling code.
3514          */
3515         if (ret <= 1)
3516                 ret = 0;
3517
3518         return ret;
3519 }
3520
3521 /*
3522  * Check whether this filesystem can be mounted based on
3523  * the features present and the RDONLY/RDWR mount requested.
3524  * Returns 1 if this filesystem can be mounted as requested,
3525  * 0 if it cannot be.
3526  */
3527 int ext4_feature_set_ok(struct super_block *sb, int readonly)
3528 {
3529         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3530                 ext4_msg(sb, KERN_ERR,
3531                         "Couldn't mount because of "
3532                         "unsupported optional features (%x)",
3533                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3534                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3535                 return 0;
3536         }
3537
3538 #if !IS_ENABLED(CONFIG_UNICODE)
3539         if (ext4_has_feature_casefold(sb)) {
3540                 ext4_msg(sb, KERN_ERR,
3541                          "Filesystem with casefold feature cannot be "
3542                          "mounted without CONFIG_UNICODE");
3543                 return 0;
3544         }
3545 #endif
3546
3547         if (readonly)
3548                 return 1;
3549
3550         if (ext4_has_feature_readonly(sb)) {
3551                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3552                 sb->s_flags |= SB_RDONLY;
3553                 return 1;
3554         }
3555
3556         /* Check that feature set is OK for a read-write mount */
3557         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3558                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3559                          "unsupported optional features (%x)",
3560                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3561                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3562                 return 0;
3563         }
3564         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3565                 ext4_msg(sb, KERN_ERR,
3566                          "Can't support bigalloc feature without "
3567                          "extents feature\n");
3568                 return 0;
3569         }
3570
3571 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3572         if (!readonly && (ext4_has_feature_quota(sb) ||
3573                           ext4_has_feature_project(sb))) {
3574                 ext4_msg(sb, KERN_ERR,
3575                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3576                 return 0;
3577         }
3578 #endif  /* CONFIG_QUOTA */
3579         return 1;
3580 }
3581
3582 /*
3583  * This function is called once a day if we have errors logged
3584  * on the file system
3585  */
3586 static void print_daily_error_info(struct timer_list *t)
3587 {
3588         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3589         struct super_block *sb = sbi->s_sb;
3590         struct ext4_super_block *es = sbi->s_es;
3591
3592         if (es->s_error_count)
3593                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3594                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3595                          le32_to_cpu(es->s_error_count));
3596         if (es->s_first_error_time) {
3597                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3598                        sb->s_id,
3599                        ext4_get_tstamp(es, s_first_error_time),
3600                        (int) sizeof(es->s_first_error_func),
3601                        es->s_first_error_func,
3602                        le32_to_cpu(es->s_first_error_line));
3603                 if (es->s_first_error_ino)
3604                         printk(KERN_CONT ": inode %u",
3605                                le32_to_cpu(es->s_first_error_ino));
3606                 if (es->s_first_error_block)
3607                         printk(KERN_CONT ": block %llu", (unsigned long long)
3608                                le64_to_cpu(es->s_first_error_block));
3609                 printk(KERN_CONT "\n");
3610         }
3611         if (es->s_last_error_time) {
3612                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3613                        sb->s_id,
3614                        ext4_get_tstamp(es, s_last_error_time),
3615                        (int) sizeof(es->s_last_error_func),
3616                        es->s_last_error_func,
3617                        le32_to_cpu(es->s_last_error_line));
3618                 if (es->s_last_error_ino)
3619                         printk(KERN_CONT ": inode %u",
3620                                le32_to_cpu(es->s_last_error_ino));
3621                 if (es->s_last_error_block)
3622                         printk(KERN_CONT ": block %llu", (unsigned long long)
3623                                le64_to_cpu(es->s_last_error_block));
3624                 printk(KERN_CONT "\n");
3625         }
3626         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3627 }
3628
3629 /* Find next suitable group and run ext4_init_inode_table */
3630 static int ext4_run_li_request(struct ext4_li_request *elr)
3631 {
3632         struct ext4_group_desc *gdp = NULL;
3633         struct super_block *sb = elr->lr_super;
3634         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3635         ext4_group_t group = elr->lr_next_group;
3636         unsigned int prefetch_ios = 0;
3637         int ret = 0;
3638         u64 start_time;
3639
3640         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3641                 elr->lr_next_group = ext4_mb_prefetch(sb, group,
3642                                 EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3643                 if (prefetch_ios)
3644                         ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3645                                               prefetch_ios);
3646                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3647                                             prefetch_ios);
3648                 if (group >= elr->lr_next_group) {
3649                         ret = 1;
3650                         if (elr->lr_first_not_zeroed != ngroups &&
3651                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3652                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3653                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3654                                 ret = 0;
3655                         }
3656                 }
3657                 return ret;
3658         }
3659
3660         for (; group < ngroups; group++) {
3661                 gdp = ext4_get_group_desc(sb, group, NULL);
3662                 if (!gdp) {
3663                         ret = 1;
3664                         break;
3665                 }
3666
3667                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3668                         break;
3669         }
3670
3671         if (group >= ngroups)
3672                 ret = 1;
3673
3674         if (!ret) {
3675                 start_time = ktime_get_real_ns();
3676                 ret = ext4_init_inode_table(sb, group,
3677                                             elr->lr_timeout ? 0 : 1);
3678                 trace_ext4_lazy_itable_init(sb, group);
3679                 if (elr->lr_timeout == 0) {
3680                         elr->lr_timeout = nsecs_to_jiffies((ktime_get_real_ns() - start_time) *
3681                                 EXT4_SB(elr->lr_super)->s_li_wait_mult);
3682                 }
3683                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3684                 elr->lr_next_group = group + 1;
3685         }
3686         return ret;
3687 }
3688
3689 /*
3690  * Remove lr_request from the list_request and free the
3691  * request structure. Should be called with li_list_mtx held
3692  */
3693 static void ext4_remove_li_request(struct ext4_li_request *elr)
3694 {
3695         if (!elr)
3696                 return;
3697
3698         list_del(&elr->lr_request);
3699         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3700         kfree(elr);
3701 }
3702
3703 static void ext4_unregister_li_request(struct super_block *sb)
3704 {
3705         mutex_lock(&ext4_li_mtx);
3706         if (!ext4_li_info) {
3707                 mutex_unlock(&ext4_li_mtx);
3708                 return;
3709         }
3710
3711         mutex_lock(&ext4_li_info->li_list_mtx);
3712         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3713         mutex_unlock(&ext4_li_info->li_list_mtx);
3714         mutex_unlock(&ext4_li_mtx);
3715 }
3716
3717 static struct task_struct *ext4_lazyinit_task;
3718
3719 /*
3720  * This is the function where ext4lazyinit thread lives. It walks
3721  * through the request list searching for next scheduled filesystem.
3722  * When such a fs is found, run the lazy initialization request
3723  * (ext4_rn_li_request) and keep track of the time spend in this
3724  * function. Based on that time we compute next schedule time of
3725  * the request. When walking through the list is complete, compute
3726  * next waking time and put itself into sleep.
3727  */
3728 static int ext4_lazyinit_thread(void *arg)
3729 {
3730         struct ext4_lazy_init *eli = arg;
3731         struct list_head *pos, *n;
3732         struct ext4_li_request *elr;
3733         unsigned long next_wakeup, cur;
3734
3735         BUG_ON(NULL == eli);
3736         set_freezable();
3737
3738 cont_thread:
3739         while (true) {
3740                 next_wakeup = MAX_JIFFY_OFFSET;
3741
3742                 mutex_lock(&eli->li_list_mtx);
3743                 if (list_empty(&eli->li_request_list)) {
3744                         mutex_unlock(&eli->li_list_mtx);
3745                         goto exit_thread;
3746                 }
3747                 list_for_each_safe(pos, n, &eli->li_request_list) {
3748                         int err = 0;
3749                         int progress = 0;
3750                         elr = list_entry(pos, struct ext4_li_request,
3751                                          lr_request);
3752
3753                         if (time_before(jiffies, elr->lr_next_sched)) {
3754                                 if (time_before(elr->lr_next_sched, next_wakeup))
3755                                         next_wakeup = elr->lr_next_sched;
3756                                 continue;
3757                         }
3758                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3759                                 if (sb_start_write_trylock(elr->lr_super)) {
3760                                         progress = 1;
3761                                         /*
3762                                          * We hold sb->s_umount, sb can not
3763                                          * be removed from the list, it is
3764                                          * now safe to drop li_list_mtx
3765                                          */
3766                                         mutex_unlock(&eli->li_list_mtx);
3767                                         err = ext4_run_li_request(elr);
3768                                         sb_end_write(elr->lr_super);
3769                                         mutex_lock(&eli->li_list_mtx);
3770                                         n = pos->next;
3771                                 }
3772                                 up_read((&elr->lr_super->s_umount));
3773                         }
3774                         /* error, remove the lazy_init job */
3775                         if (err) {
3776                                 ext4_remove_li_request(elr);
3777                                 continue;
3778                         }
3779                         if (!progress) {
3780                                 elr->lr_next_sched = jiffies +
3781                                         prandom_u32_max(EXT4_DEF_LI_MAX_START_DELAY * HZ);
3782                         }
3783                         if (time_before(elr->lr_next_sched, next_wakeup))
3784                                 next_wakeup = elr->lr_next_sched;
3785                 }
3786                 mutex_unlock(&eli->li_list_mtx);
3787
3788                 try_to_freeze();
3789
3790                 cur = jiffies;
3791                 if ((time_after_eq(cur, next_wakeup)) ||
3792                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3793                         cond_resched();
3794                         continue;
3795                 }
3796
3797                 schedule_timeout_interruptible(next_wakeup - cur);
3798
3799                 if (kthread_should_stop()) {
3800                         ext4_clear_request_list();
3801                         goto exit_thread;
3802                 }
3803         }
3804
3805 exit_thread:
3806         /*
3807          * It looks like the request list is empty, but we need
3808          * to check it under the li_list_mtx lock, to prevent any
3809          * additions into it, and of course we should lock ext4_li_mtx
3810          * to atomically free the list and ext4_li_info, because at
3811          * this point another ext4 filesystem could be registering
3812          * new one.
3813          */
3814         mutex_lock(&ext4_li_mtx);
3815         mutex_lock(&eli->li_list_mtx);
3816         if (!list_empty(&eli->li_request_list)) {
3817                 mutex_unlock(&eli->li_list_mtx);
3818                 mutex_unlock(&ext4_li_mtx);
3819                 goto cont_thread;
3820         }
3821         mutex_unlock(&eli->li_list_mtx);
3822         kfree(ext4_li_info);
3823         ext4_li_info = NULL;
3824         mutex_unlock(&ext4_li_mtx);
3825
3826         return 0;
3827 }
3828
3829 static void ext4_clear_request_list(void)
3830 {
3831         struct list_head *pos, *n;
3832         struct ext4_li_request *elr;
3833
3834         mutex_lock(&ext4_li_info->li_list_mtx);
3835         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3836                 elr = list_entry(pos, struct ext4_li_request,
3837                                  lr_request);
3838                 ext4_remove_li_request(elr);
3839         }
3840         mutex_unlock(&ext4_li_info->li_list_mtx);
3841 }
3842
3843 static int ext4_run_lazyinit_thread(void)
3844 {
3845         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3846                                          ext4_li_info, "ext4lazyinit");
3847         if (IS_ERR(ext4_lazyinit_task)) {
3848                 int err = PTR_ERR(ext4_lazyinit_task);
3849                 ext4_clear_request_list();
3850                 kfree(ext4_li_info);
3851                 ext4_li_info = NULL;
3852                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3853                                  "initialization thread\n",
3854                                  err);
3855                 return err;
3856         }
3857         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3858         return 0;
3859 }
3860
3861 /*
3862  * Check whether it make sense to run itable init. thread or not.
3863  * If there is at least one uninitialized inode table, return
3864  * corresponding group number, else the loop goes through all
3865  * groups and return total number of groups.
3866  */
3867 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3868 {
3869         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3870         struct ext4_group_desc *gdp = NULL;
3871
3872         if (!ext4_has_group_desc_csum(sb))
3873                 return ngroups;
3874
3875         for (group = 0; group < ngroups; group++) {
3876                 gdp = ext4_get_group_desc(sb, group, NULL);
3877                 if (!gdp)
3878                         continue;
3879
3880                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3881                         break;
3882         }
3883
3884         return group;
3885 }
3886
3887 static int ext4_li_info_new(void)
3888 {
3889         struct ext4_lazy_init *eli = NULL;
3890
3891         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3892         if (!eli)
3893                 return -ENOMEM;
3894
3895         INIT_LIST_HEAD(&eli->li_request_list);
3896         mutex_init(&eli->li_list_mtx);
3897
3898         eli->li_state |= EXT4_LAZYINIT_QUIT;
3899
3900         ext4_li_info = eli;
3901
3902         return 0;
3903 }
3904
3905 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3906                                             ext4_group_t start)
3907 {
3908         struct ext4_li_request *elr;
3909
3910         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3911         if (!elr)
3912                 return NULL;
3913
3914         elr->lr_super = sb;
3915         elr->lr_first_not_zeroed = start;
3916         if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS)) {
3917                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3918                 elr->lr_next_group = start;
3919         } else {
3920                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3921         }
3922
3923         /*
3924          * Randomize first schedule time of the request to
3925          * spread the inode table initialization requests
3926          * better.
3927          */
3928         elr->lr_next_sched = jiffies + prandom_u32_max(
3929                                 EXT4_DEF_LI_MAX_START_DELAY * HZ);
3930         return elr;
3931 }
3932
3933 int ext4_register_li_request(struct super_block *sb,
3934                              ext4_group_t first_not_zeroed)
3935 {
3936         struct ext4_sb_info *sbi = EXT4_SB(sb);
3937         struct ext4_li_request *elr = NULL;
3938         ext4_group_t ngroups = sbi->s_groups_count;
3939         int ret = 0;
3940
3941         mutex_lock(&ext4_li_mtx);
3942         if (sbi->s_li_request != NULL) {
3943                 /*
3944                  * Reset timeout so it can be computed again, because
3945                  * s_li_wait_mult might have changed.
3946                  */
3947                 sbi->s_li_request->lr_timeout = 0;
3948                 goto out;
3949         }
3950
3951         if (sb_rdonly(sb) ||
3952             (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS) &&
3953              (first_not_zeroed == ngroups || !test_opt(sb, INIT_INODE_TABLE))))
3954                 goto out;
3955
3956         elr = ext4_li_request_new(sb, first_not_zeroed);
3957         if (!elr) {
3958                 ret = -ENOMEM;
3959                 goto out;
3960         }
3961
3962         if (NULL == ext4_li_info) {
3963                 ret = ext4_li_info_new();
3964                 if (ret)
3965                         goto out;
3966         }
3967
3968         mutex_lock(&ext4_li_info->li_list_mtx);
3969         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3970         mutex_unlock(&ext4_li_info->li_list_mtx);
3971
3972         sbi->s_li_request = elr;
3973         /*
3974          * set elr to NULL here since it has been inserted to
3975          * the request_list and the removal and free of it is
3976          * handled by ext4_clear_request_list from now on.
3977          */
3978         elr = NULL;
3979
3980         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3981                 ret = ext4_run_lazyinit_thread();
3982                 if (ret)
3983                         goto out;
3984         }
3985 out:
3986         mutex_unlock(&ext4_li_mtx);
3987         if (ret)
3988                 kfree(elr);
3989         return ret;
3990 }
3991
3992 /*
3993  * We do not need to lock anything since this is called on
3994  * module unload.
3995  */
3996 static void ext4_destroy_lazyinit_thread(void)
3997 {
3998         /*
3999          * If thread exited earlier
4000          * there's nothing to be done.
4001          */
4002         if (!ext4_li_info || !ext4_lazyinit_task)
4003                 return;
4004
4005         kthread_stop(ext4_lazyinit_task);
4006 }
4007
4008 static int set_journal_csum_feature_set(struct super_block *sb)
4009 {
4010         int ret = 1;
4011         int compat, incompat;
4012         struct ext4_sb_info *sbi = EXT4_SB(sb);
4013
4014         if (ext4_has_metadata_csum(sb)) {
4015                 /* journal checksum v3 */
4016                 compat = 0;
4017                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
4018         } else {
4019                 /* journal checksum v1 */
4020                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
4021                 incompat = 0;
4022         }
4023
4024         jbd2_journal_clear_features(sbi->s_journal,
4025                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
4026                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
4027                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
4028         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4029                 ret = jbd2_journal_set_features(sbi->s_journal,
4030                                 compat, 0,
4031                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
4032                                 incompat);
4033         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
4034                 ret = jbd2_journal_set_features(sbi->s_journal,
4035                                 compat, 0,
4036                                 incompat);
4037                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4038                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4039         } else {
4040                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4041                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4042         }
4043
4044         return ret;
4045 }
4046
4047 /*
4048  * Note: calculating the overhead so we can be compatible with
4049  * historical BSD practice is quite difficult in the face of
4050  * clusters/bigalloc.  This is because multiple metadata blocks from
4051  * different block group can end up in the same allocation cluster.
4052  * Calculating the exact overhead in the face of clustered allocation
4053  * requires either O(all block bitmaps) in memory or O(number of block
4054  * groups**2) in time.  We will still calculate the superblock for
4055  * older file systems --- and if we come across with a bigalloc file
4056  * system with zero in s_overhead_clusters the estimate will be close to
4057  * correct especially for very large cluster sizes --- but for newer
4058  * file systems, it's better to calculate this figure once at mkfs
4059  * time, and store it in the superblock.  If the superblock value is
4060  * present (even for non-bigalloc file systems), we will use it.
4061  */
4062 static int count_overhead(struct super_block *sb, ext4_group_t grp,
4063                           char *buf)
4064 {
4065         struct ext4_sb_info     *sbi = EXT4_SB(sb);
4066         struct ext4_group_desc  *gdp;
4067         ext4_fsblk_t            first_block, last_block, b;
4068         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
4069         int                     s, j, count = 0;
4070         int                     has_super = ext4_bg_has_super(sb, grp);
4071
4072         if (!ext4_has_feature_bigalloc(sb))
4073                 return (has_super + ext4_bg_num_gdb(sb, grp) +
4074                         (has_super ? le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0) +
4075                         sbi->s_itb_per_group + 2);
4076
4077         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
4078                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
4079         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
4080         for (i = 0; i < ngroups; i++) {
4081                 gdp = ext4_get_group_desc(sb, i, NULL);
4082                 b = ext4_block_bitmap(sb, gdp);
4083                 if (b >= first_block && b <= last_block) {
4084                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4085                         count++;
4086                 }
4087                 b = ext4_inode_bitmap(sb, gdp);
4088                 if (b >= first_block && b <= last_block) {
4089                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4090                         count++;
4091                 }
4092                 b = ext4_inode_table(sb, gdp);
4093                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
4094                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
4095                                 int c = EXT4_B2C(sbi, b - first_block);
4096                                 ext4_set_bit(c, buf);
4097                                 count++;
4098                         }
4099                 if (i != grp)
4100                         continue;
4101                 s = 0;
4102                 if (ext4_bg_has_super(sb, grp)) {
4103                         ext4_set_bit(s++, buf);
4104                         count++;
4105                 }
4106                 j = ext4_bg_num_gdb(sb, grp);
4107                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
4108                         ext4_error(sb, "Invalid number of block group "
4109                                    "descriptor blocks: %d", j);
4110                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
4111                 }
4112                 count += j;
4113                 for (; j > 0; j--)
4114                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
4115         }
4116         if (!count)
4117                 return 0;
4118         return EXT4_CLUSTERS_PER_GROUP(sb) -
4119                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
4120 }
4121
4122 /*
4123  * Compute the overhead and stash it in sbi->s_overhead
4124  */
4125 int ext4_calculate_overhead(struct super_block *sb)
4126 {
4127         struct ext4_sb_info *sbi = EXT4_SB(sb);
4128         struct ext4_super_block *es = sbi->s_es;
4129         struct inode *j_inode;
4130         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
4131         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4132         ext4_fsblk_t overhead = 0;
4133         char *buf = (char *) get_zeroed_page(GFP_NOFS);
4134
4135         if (!buf)
4136                 return -ENOMEM;
4137
4138         /*
4139          * Compute the overhead (FS structures).  This is constant
4140          * for a given filesystem unless the number of block groups
4141          * changes so we cache the previous value until it does.
4142          */
4143
4144         /*
4145          * All of the blocks before first_data_block are overhead
4146          */
4147         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
4148
4149         /*
4150          * Add the overhead found in each block group
4151          */
4152         for (i = 0; i < ngroups; i++) {
4153                 int blks;
4154
4155                 blks = count_overhead(sb, i, buf);
4156                 overhead += blks;
4157                 if (blks)
4158                         memset(buf, 0, PAGE_SIZE);
4159                 cond_resched();
4160         }
4161
4162         /*
4163          * Add the internal journal blocks whether the journal has been
4164          * loaded or not
4165          */
4166         if (sbi->s_journal && !sbi->s_journal_bdev)
4167                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
4168         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
4169                 /* j_inum for internal journal is non-zero */
4170                 j_inode = ext4_get_journal_inode(sb, j_inum);
4171                 if (j_inode) {
4172                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
4173                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
4174                         iput(j_inode);
4175                 } else {
4176                         ext4_msg(sb, KERN_ERR, "can't get journal size");
4177                 }
4178         }
4179         sbi->s_overhead = overhead;
4180         smp_wmb();
4181         free_page((unsigned long) buf);
4182         return 0;
4183 }
4184
4185 static void ext4_set_resv_clusters(struct super_block *sb)
4186 {
4187         ext4_fsblk_t resv_clusters;
4188         struct ext4_sb_info *sbi = EXT4_SB(sb);
4189
4190         /*
4191          * There's no need to reserve anything when we aren't using extents.
4192          * The space estimates are exact, there are no unwritten extents,
4193          * hole punching doesn't need new metadata... This is needed especially
4194          * to keep ext2/3 backward compatibility.
4195          */
4196         if (!ext4_has_feature_extents(sb))
4197                 return;
4198         /*
4199          * By default we reserve 2% or 4096 clusters, whichever is smaller.
4200          * This should cover the situations where we can not afford to run
4201          * out of space like for example punch hole, or converting
4202          * unwritten extents in delalloc path. In most cases such
4203          * allocation would require 1, or 2 blocks, higher numbers are
4204          * very rare.
4205          */
4206         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4207                          sbi->s_cluster_bits);
4208
4209         do_div(resv_clusters, 50);
4210         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4211
4212         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4213 }
4214
4215 static const char *ext4_quota_mode(struct super_block *sb)
4216 {
4217 #ifdef CONFIG_QUOTA
4218         if (!ext4_quota_capable(sb))
4219                 return "none";
4220
4221         if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
4222                 return "journalled";
4223         else
4224                 return "writeback";
4225 #else
4226         return "disabled";
4227 #endif
4228 }
4229
4230 static void ext4_setup_csum_trigger(struct super_block *sb,
4231                                     enum ext4_journal_trigger_type type,
4232                                     void (*trigger)(
4233                                         struct jbd2_buffer_trigger_type *type,
4234                                         struct buffer_head *bh,
4235                                         void *mapped_data,
4236                                         size_t size))
4237 {
4238         struct ext4_sb_info *sbi = EXT4_SB(sb);
4239
4240         sbi->s_journal_triggers[type].sb = sb;
4241         sbi->s_journal_triggers[type].tr_triggers.t_frozen = trigger;
4242 }
4243
4244 static void ext4_free_sbi(struct ext4_sb_info *sbi)
4245 {
4246         if (!sbi)
4247                 return;
4248
4249         kfree(sbi->s_blockgroup_lock);
4250         fs_put_dax(sbi->s_daxdev, NULL);
4251         kfree(sbi);
4252 }
4253
4254 static struct ext4_sb_info *ext4_alloc_sbi(struct super_block *sb)
4255 {
4256         struct ext4_sb_info *sbi;
4257
4258         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4259         if (!sbi)
4260                 return NULL;
4261
4262         sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off,
4263                                            NULL, NULL);
4264
4265         sbi->s_blockgroup_lock =
4266                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4267
4268         if (!sbi->s_blockgroup_lock)
4269                 goto err_out;
4270
4271         sb->s_fs_info = sbi;
4272         sbi->s_sb = sb;
4273         return sbi;
4274 err_out:
4275         fs_put_dax(sbi->s_daxdev, NULL);
4276         kfree(sbi);
4277         return NULL;
4278 }
4279
4280 static void ext4_set_def_opts(struct super_block *sb,
4281                               struct ext4_super_block *es)
4282 {
4283         unsigned long def_mount_opts;
4284
4285         /* Set defaults before we parse the mount options */
4286         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4287         set_opt(sb, INIT_INODE_TABLE);
4288         if (def_mount_opts & EXT4_DEFM_DEBUG)
4289                 set_opt(sb, DEBUG);
4290         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4291                 set_opt(sb, GRPID);
4292         if (def_mount_opts & EXT4_DEFM_UID16)
4293                 set_opt(sb, NO_UID32);
4294         /* xattr user namespace & acls are now defaulted on */
4295         set_opt(sb, XATTR_USER);
4296 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4297         set_opt(sb, POSIX_ACL);
4298 #endif
4299         if (ext4_has_feature_fast_commit(sb))
4300                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4301         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4302         if (ext4_has_metadata_csum(sb))
4303                 set_opt(sb, JOURNAL_CHECKSUM);
4304
4305         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4306                 set_opt(sb, JOURNAL_DATA);
4307         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4308                 set_opt(sb, ORDERED_DATA);
4309         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4310                 set_opt(sb, WRITEBACK_DATA);
4311
4312         if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_PANIC)
4313                 set_opt(sb, ERRORS_PANIC);
4314         else if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_CONTINUE)
4315                 set_opt(sb, ERRORS_CONT);
4316         else
4317                 set_opt(sb, ERRORS_RO);
4318         /* block_validity enabled by default; disable with noblock_validity */
4319         set_opt(sb, BLOCK_VALIDITY);
4320         if (def_mount_opts & EXT4_DEFM_DISCARD)
4321                 set_opt(sb, DISCARD);
4322
4323         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4324                 set_opt(sb, BARRIER);
4325
4326         /*
4327          * enable delayed allocation by default
4328          * Use -o nodelalloc to turn it off
4329          */
4330         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4331             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4332                 set_opt(sb, DELALLOC);
4333
4334         if (sb->s_blocksize == PAGE_SIZE)
4335                 set_opt(sb, DIOREAD_NOLOCK);
4336 }
4337
4338 static int ext4_handle_clustersize(struct super_block *sb)
4339 {
4340         struct ext4_sb_info *sbi = EXT4_SB(sb);
4341         struct ext4_super_block *es = sbi->s_es;
4342         int clustersize;
4343
4344         /* Handle clustersize */
4345         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4346         if (ext4_has_feature_bigalloc(sb)) {
4347                 if (clustersize < sb->s_blocksize) {
4348                         ext4_msg(sb, KERN_ERR,
4349                                  "cluster size (%d) smaller than "
4350                                  "block size (%lu)", clustersize, sb->s_blocksize);
4351                         return -EINVAL;
4352                 }
4353                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4354                         le32_to_cpu(es->s_log_block_size);
4355                 sbi->s_clusters_per_group =
4356                         le32_to_cpu(es->s_clusters_per_group);
4357                 if (sbi->s_clusters_per_group > sb->s_blocksize * 8) {
4358                         ext4_msg(sb, KERN_ERR,
4359                                  "#clusters per group too big: %lu",
4360                                  sbi->s_clusters_per_group);
4361                         return -EINVAL;
4362                 }
4363                 if (sbi->s_blocks_per_group !=
4364                     (sbi->s_clusters_per_group * (clustersize / sb->s_blocksize))) {
4365                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4366                                  "clusters per group (%lu) inconsistent",
4367                                  sbi->s_blocks_per_group,
4368                                  sbi->s_clusters_per_group);
4369                         return -EINVAL;
4370                 }
4371         } else {
4372                 if (clustersize != sb->s_blocksize) {
4373                         ext4_msg(sb, KERN_ERR,
4374                                  "fragment/cluster size (%d) != "
4375                                  "block size (%lu)", clustersize, sb->s_blocksize);
4376                         return -EINVAL;
4377                 }
4378                 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
4379                         ext4_msg(sb, KERN_ERR,
4380                                  "#blocks per group too big: %lu",
4381                                  sbi->s_blocks_per_group);
4382                         return -EINVAL;
4383                 }
4384                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4385                 sbi->s_cluster_bits = 0;
4386         }
4387         sbi->s_cluster_ratio = clustersize / sb->s_blocksize;
4388
4389         /* Do we have standard group size of clustersize * 8 blocks ? */
4390         if (sbi->s_blocks_per_group == clustersize << 3)
4391                 set_opt2(sb, STD_GROUP_SIZE);
4392
4393         return 0;
4394 }
4395
4396 static void ext4_fast_commit_init(struct super_block *sb)
4397 {
4398         struct ext4_sb_info *sbi = EXT4_SB(sb);
4399
4400         /* Initialize fast commit stuff */
4401         atomic_set(&sbi->s_fc_subtid, 0);
4402         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4403         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4404         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4405         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4406         sbi->s_fc_bytes = 0;
4407         ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
4408         sbi->s_fc_ineligible_tid = 0;
4409         spin_lock_init(&sbi->s_fc_lock);
4410         memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4411         sbi->s_fc_replay_state.fc_regions = NULL;
4412         sbi->s_fc_replay_state.fc_regions_size = 0;
4413         sbi->s_fc_replay_state.fc_regions_used = 0;
4414         sbi->s_fc_replay_state.fc_regions_valid = 0;
4415         sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4416         sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4417         sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4418 }
4419
4420 static int ext4_inode_info_init(struct super_block *sb,
4421                                 struct ext4_super_block *es)
4422 {
4423         struct ext4_sb_info *sbi = EXT4_SB(sb);
4424
4425         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4426                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4427                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4428         } else {
4429                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4430                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4431                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4432                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4433                                  sbi->s_first_ino);
4434                         return -EINVAL;
4435                 }
4436                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4437                     (!is_power_of_2(sbi->s_inode_size)) ||
4438                     (sbi->s_inode_size > sb->s_blocksize)) {
4439                         ext4_msg(sb, KERN_ERR,
4440                                "unsupported inode size: %d",
4441                                sbi->s_inode_size);
4442                         ext4_msg(sb, KERN_ERR, "blocksize: %lu", sb->s_blocksize);
4443                         return -EINVAL;
4444                 }
4445                 /*
4446                  * i_atime_extra is the last extra field available for
4447                  * [acm]times in struct ext4_inode. Checking for that
4448                  * field should suffice to ensure we have extra space
4449                  * for all three.
4450                  */
4451                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4452                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4453                         sb->s_time_gran = 1;
4454                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4455                 } else {
4456                         sb->s_time_gran = NSEC_PER_SEC;
4457                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4458                 }
4459                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4460         }
4461
4462         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4463                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4464                         EXT4_GOOD_OLD_INODE_SIZE;
4465                 if (ext4_has_feature_extra_isize(sb)) {
4466                         unsigned v, max = (sbi->s_inode_size -
4467                                            EXT4_GOOD_OLD_INODE_SIZE);
4468
4469                         v = le16_to_cpu(es->s_want_extra_isize);
4470                         if (v > max) {
4471                                 ext4_msg(sb, KERN_ERR,
4472                                          "bad s_want_extra_isize: %d", v);
4473                                 return -EINVAL;
4474                         }
4475                         if (sbi->s_want_extra_isize < v)
4476                                 sbi->s_want_extra_isize = v;
4477
4478                         v = le16_to_cpu(es->s_min_extra_isize);
4479                         if (v > max) {
4480                                 ext4_msg(sb, KERN_ERR,
4481                                          "bad s_min_extra_isize: %d", v);
4482                                 return -EINVAL;
4483                         }
4484                         if (sbi->s_want_extra_isize < v)
4485                                 sbi->s_want_extra_isize = v;
4486                 }
4487         }
4488
4489         return 0;
4490 }
4491
4492 #if IS_ENABLED(CONFIG_UNICODE)
4493 static int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4494 {
4495         const struct ext4_sb_encodings *encoding_info;
4496         struct unicode_map *encoding;
4497         __u16 encoding_flags = le16_to_cpu(es->s_encoding_flags);
4498
4499         if (!ext4_has_feature_casefold(sb) || sb->s_encoding)
4500                 return 0;
4501
4502         encoding_info = ext4_sb_read_encoding(es);
4503         if (!encoding_info) {
4504                 ext4_msg(sb, KERN_ERR,
4505                         "Encoding requested by superblock is unknown");
4506                 return -EINVAL;
4507         }
4508
4509         encoding = utf8_load(encoding_info->version);
4510         if (IS_ERR(encoding)) {
4511                 ext4_msg(sb, KERN_ERR,
4512                         "can't mount with superblock charset: %s-%u.%u.%u "
4513                         "not supported by the kernel. flags: 0x%x.",
4514                         encoding_info->name,
4515                         unicode_major(encoding_info->version),
4516                         unicode_minor(encoding_info->version),
4517                         unicode_rev(encoding_info->version),
4518                         encoding_flags);
4519                 return -EINVAL;
4520         }
4521         ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4522                 "%s-%u.%u.%u with flags 0x%hx", encoding_info->name,
4523                 unicode_major(encoding_info->version),
4524                 unicode_minor(encoding_info->version),
4525                 unicode_rev(encoding_info->version),
4526                 encoding_flags);
4527
4528         sb->s_encoding = encoding;
4529         sb->s_encoding_flags = encoding_flags;
4530
4531         return 0;
4532 }
4533 #else
4534 static inline int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4535 {
4536         return 0;
4537 }
4538 #endif
4539
4540 static int ext4_init_metadata_csum(struct super_block *sb, struct ext4_super_block *es)
4541 {
4542         struct ext4_sb_info *sbi = EXT4_SB(sb);
4543
4544         /* Warn if metadata_csum and gdt_csum are both set. */
4545         if (ext4_has_feature_metadata_csum(sb) &&
4546             ext4_has_feature_gdt_csum(sb))
4547                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4548                              "redundant flags; please run fsck.");
4549
4550         /* Check for a known checksum algorithm */
4551         if (!ext4_verify_csum_type(sb, es)) {
4552                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4553                          "unknown checksum algorithm.");
4554                 return -EINVAL;
4555         }
4556         ext4_setup_csum_trigger(sb, EXT4_JTR_ORPHAN_FILE,
4557                                 ext4_orphan_file_block_trigger);
4558
4559         /* Load the checksum driver */
4560         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4561         if (IS_ERR(sbi->s_chksum_driver)) {
4562                 int ret = PTR_ERR(sbi->s_chksum_driver);
4563                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4564                 sbi->s_chksum_driver = NULL;
4565                 return ret;
4566         }
4567
4568         /* Check superblock checksum */
4569         if (!ext4_superblock_csum_verify(sb, es)) {
4570                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4571                          "invalid superblock checksum.  Run e2fsck?");
4572                 return -EFSBADCRC;
4573         }
4574
4575         /* Precompute checksum seed for all metadata */
4576         if (ext4_has_feature_csum_seed(sb))
4577                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4578         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4579                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4580                                                sizeof(es->s_uuid));
4581         return 0;
4582 }
4583
4584 static int ext4_check_feature_compatibility(struct super_block *sb,
4585                                             struct ext4_super_block *es,
4586                                             int silent)
4587 {
4588         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4589             (ext4_has_compat_features(sb) ||
4590              ext4_has_ro_compat_features(sb) ||
4591              ext4_has_incompat_features(sb)))
4592                 ext4_msg(sb, KERN_WARNING,
4593                        "feature flags set on rev 0 fs, "
4594                        "running e2fsck is recommended");
4595
4596         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4597                 set_opt2(sb, HURD_COMPAT);
4598                 if (ext4_has_feature_64bit(sb)) {
4599                         ext4_msg(sb, KERN_ERR,
4600                                  "The Hurd can't support 64-bit file systems");
4601                         return -EINVAL;
4602                 }
4603
4604                 /*
4605                  * ea_inode feature uses l_i_version field which is not
4606                  * available in HURD_COMPAT mode.
4607                  */
4608                 if (ext4_has_feature_ea_inode(sb)) {
4609                         ext4_msg(sb, KERN_ERR,
4610                                  "ea_inode feature is not supported for Hurd");
4611                         return -EINVAL;
4612                 }
4613         }
4614
4615         if (IS_EXT2_SB(sb)) {
4616                 if (ext2_feature_set_ok(sb))
4617                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4618                                  "using the ext4 subsystem");
4619                 else {
4620                         /*
4621                          * If we're probing be silent, if this looks like
4622                          * it's actually an ext[34] filesystem.
4623                          */
4624                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4625                                 return -EINVAL;
4626                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4627                                  "to feature incompatibilities");
4628                         return -EINVAL;
4629                 }
4630         }
4631
4632         if (IS_EXT3_SB(sb)) {
4633                 if (ext3_feature_set_ok(sb))
4634                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4635                                  "using the ext4 subsystem");
4636                 else {
4637                         /*
4638                          * If we're probing be silent, if this looks like
4639                          * it's actually an ext4 filesystem.
4640                          */
4641                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4642                                 return -EINVAL;
4643                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4644                                  "to feature incompatibilities");
4645                         return -EINVAL;
4646                 }
4647         }
4648
4649         /*
4650          * Check feature flags regardless of the revision level, since we
4651          * previously didn't change the revision level when setting the flags,
4652          * so there is a chance incompat flags are set on a rev 0 filesystem.
4653          */
4654         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4655                 return -EINVAL;
4656
4657         return 0;
4658 }
4659
4660 static int ext4_geometry_check(struct super_block *sb,
4661                                struct ext4_super_block *es)
4662 {
4663         struct ext4_sb_info *sbi = EXT4_SB(sb);
4664         __u64 blocks_count;
4665
4666         /* check blocks count against device size */
4667         blocks_count = sb_bdev_nr_blocks(sb);
4668         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4669                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4670                        "exceeds size of device (%llu blocks)",
4671                        ext4_blocks_count(es), blocks_count);
4672                 return -EINVAL;
4673         }
4674
4675         /*
4676          * It makes no sense for the first data block to be beyond the end
4677          * of the filesystem.
4678          */
4679         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4680                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4681                          "block %u is beyond end of filesystem (%llu)",
4682                          le32_to_cpu(es->s_first_data_block),
4683                          ext4_blocks_count(es));
4684                 return -EINVAL;
4685         }
4686         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4687             (sbi->s_cluster_ratio == 1)) {
4688                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4689                          "block is 0 with a 1k block and cluster size");
4690                 return -EINVAL;
4691         }
4692
4693         blocks_count = (ext4_blocks_count(es) -
4694                         le32_to_cpu(es->s_first_data_block) +
4695                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4696         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4697         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4698                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4699                        "(block count %llu, first data block %u, "
4700                        "blocks per group %lu)", blocks_count,
4701                        ext4_blocks_count(es),
4702                        le32_to_cpu(es->s_first_data_block),
4703                        EXT4_BLOCKS_PER_GROUP(sb));
4704                 return -EINVAL;
4705         }
4706         sbi->s_groups_count = blocks_count;
4707         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4708                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4709         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4710             le32_to_cpu(es->s_inodes_count)) {
4711                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4712                          le32_to_cpu(es->s_inodes_count),
4713                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4714                 return -EINVAL;
4715         }
4716
4717         return 0;
4718 }
4719
4720 static void ext4_group_desc_free(struct ext4_sb_info *sbi)
4721 {
4722         struct buffer_head **group_desc;
4723         int i;
4724
4725         rcu_read_lock();
4726         group_desc = rcu_dereference(sbi->s_group_desc);
4727         for (i = 0; i < sbi->s_gdb_count; i++)
4728                 brelse(group_desc[i]);
4729         kvfree(group_desc);
4730         rcu_read_unlock();
4731 }
4732
4733 static int ext4_group_desc_init(struct super_block *sb,
4734                                 struct ext4_super_block *es,
4735                                 ext4_fsblk_t logical_sb_block,
4736                                 ext4_group_t *first_not_zeroed)
4737 {
4738         struct ext4_sb_info *sbi = EXT4_SB(sb);
4739         unsigned int db_count;
4740         ext4_fsblk_t block;
4741         int ret;
4742         int i;
4743
4744         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4745                    EXT4_DESC_PER_BLOCK(sb);
4746         if (ext4_has_feature_meta_bg(sb)) {
4747                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4748                         ext4_msg(sb, KERN_WARNING,
4749                                  "first meta block group too large: %u "
4750                                  "(group descriptor block count %u)",
4751                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4752                         return -EINVAL;
4753                 }
4754         }
4755         rcu_assign_pointer(sbi->s_group_desc,
4756                            kvmalloc_array(db_count,
4757                                           sizeof(struct buffer_head *),
4758                                           GFP_KERNEL));
4759         if (sbi->s_group_desc == NULL) {
4760                 ext4_msg(sb, KERN_ERR, "not enough memory");
4761                 return -ENOMEM;
4762         }
4763
4764         bgl_lock_init(sbi->s_blockgroup_lock);
4765
4766         /* Pre-read the descriptors into the buffer cache */
4767         for (i = 0; i < db_count; i++) {
4768                 block = descriptor_loc(sb, logical_sb_block, i);
4769                 ext4_sb_breadahead_unmovable(sb, block);
4770         }
4771
4772         for (i = 0; i < db_count; i++) {
4773                 struct buffer_head *bh;
4774
4775                 block = descriptor_loc(sb, logical_sb_block, i);
4776                 bh = ext4_sb_bread_unmovable(sb, block);
4777                 if (IS_ERR(bh)) {
4778                         ext4_msg(sb, KERN_ERR,
4779                                "can't read group descriptor %d", i);
4780                         sbi->s_gdb_count = i;
4781                         ret = PTR_ERR(bh);
4782                         goto out;
4783                 }
4784                 rcu_read_lock();
4785                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4786                 rcu_read_unlock();
4787         }
4788         sbi->s_gdb_count = db_count;
4789         if (!ext4_check_descriptors(sb, logical_sb_block, first_not_zeroed)) {
4790                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4791                 ret = -EFSCORRUPTED;
4792                 goto out;
4793         }
4794         return 0;
4795 out:
4796         ext4_group_desc_free(sbi);
4797         return ret;
4798 }
4799
4800 static int ext4_load_and_init_journal(struct super_block *sb,
4801                                       struct ext4_super_block *es,
4802                                       struct ext4_fs_context *ctx)
4803 {
4804         struct ext4_sb_info *sbi = EXT4_SB(sb);
4805         int err;
4806
4807         err = ext4_load_journal(sb, es, ctx->journal_devnum);
4808         if (err)
4809                 return err;
4810
4811         if (ext4_has_feature_64bit(sb) &&
4812             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4813                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4814                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4815                 goto out;
4816         }
4817
4818         if (!set_journal_csum_feature_set(sb)) {
4819                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4820                          "feature set");
4821                 goto out;
4822         }
4823
4824         if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4825                 !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4826                                           JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
4827                 ext4_msg(sb, KERN_ERR,
4828                         "Failed to set fast commit journal feature");
4829                 goto out;
4830         }
4831
4832         /* We have now updated the journal if required, so we can
4833          * validate the data journaling mode. */
4834         switch (test_opt(sb, DATA_FLAGS)) {
4835         case 0:
4836                 /* No mode set, assume a default based on the journal
4837                  * capabilities: ORDERED_DATA if the journal can
4838                  * cope, else JOURNAL_DATA
4839                  */
4840                 if (jbd2_journal_check_available_features
4841                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4842                         set_opt(sb, ORDERED_DATA);
4843                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4844                 } else {
4845                         set_opt(sb, JOURNAL_DATA);
4846                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4847                 }
4848                 break;
4849
4850         case EXT4_MOUNT_ORDERED_DATA:
4851         case EXT4_MOUNT_WRITEBACK_DATA:
4852                 if (!jbd2_journal_check_available_features
4853                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4854                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4855                                "requested data journaling mode");
4856                         goto out;
4857                 }
4858                 break;
4859         default:
4860                 break;
4861         }
4862
4863         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4864             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4865                 ext4_msg(sb, KERN_ERR, "can't mount with "
4866                         "journal_async_commit in data=ordered mode");
4867                 goto out;
4868         }
4869
4870         set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
4871
4872         sbi->s_journal->j_submit_inode_data_buffers =
4873                 ext4_journal_submit_inode_data_buffers;
4874         sbi->s_journal->j_finish_inode_data_buffers =
4875                 ext4_journal_finish_inode_data_buffers;
4876
4877         return 0;
4878
4879 out:
4880         /* flush s_error_work before journal destroy. */
4881         flush_work(&sbi->s_error_work);
4882         jbd2_journal_destroy(sbi->s_journal);
4883         sbi->s_journal = NULL;
4884         return -EINVAL;
4885 }
4886
4887 static int ext4_journal_data_mode_check(struct super_block *sb)
4888 {
4889         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4890                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with "
4891                             "data=journal disables delayed allocation, "
4892                             "dioread_nolock, O_DIRECT and fast_commit support!\n");
4893                 /* can't mount with both data=journal and dioread_nolock. */
4894                 clear_opt(sb, DIOREAD_NOLOCK);
4895                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4896                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4897                         ext4_msg(sb, KERN_ERR, "can't mount with "
4898                                  "both data=journal and delalloc");
4899                         return -EINVAL;
4900                 }
4901                 if (test_opt(sb, DAX_ALWAYS)) {
4902                         ext4_msg(sb, KERN_ERR, "can't mount with "
4903                                  "both data=journal and dax");
4904                         return -EINVAL;
4905                 }
4906                 if (ext4_has_feature_encrypt(sb)) {
4907                         ext4_msg(sb, KERN_WARNING,
4908                                  "encrypted files will use data=ordered "
4909                                  "instead of data journaling mode");
4910                 }
4911                 if (test_opt(sb, DELALLOC))
4912                         clear_opt(sb, DELALLOC);
4913         } else {
4914                 sb->s_iflags |= SB_I_CGROUPWB;
4915         }
4916
4917         return 0;
4918 }
4919
4920 static int ext4_load_super(struct super_block *sb, ext4_fsblk_t *lsb,
4921                            int silent)
4922 {
4923         struct ext4_sb_info *sbi = EXT4_SB(sb);
4924         struct ext4_super_block *es;
4925         ext4_fsblk_t logical_sb_block;
4926         unsigned long offset = 0;
4927         struct buffer_head *bh;
4928         int ret = -EINVAL;
4929         int blocksize;
4930
4931         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
4932         if (!blocksize) {
4933                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
4934                 return -EINVAL;
4935         }
4936
4937         /*
4938          * The ext4 superblock will not be buffer aligned for other than 1kB
4939          * block sizes.  We need to calculate the offset from buffer start.
4940          */
4941         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
4942                 logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
4943                 offset = do_div(logical_sb_block, blocksize);
4944         } else {
4945                 logical_sb_block = sbi->s_sb_block;
4946         }
4947
4948         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4949         if (IS_ERR(bh)) {
4950                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
4951                 return PTR_ERR(bh);
4952         }
4953         /*
4954          * Note: s_es must be initialized as soon as possible because
4955          *       some ext4 macro-instructions depend on its value
4956          */
4957         es = (struct ext4_super_block *) (bh->b_data + offset);
4958         sbi->s_es = es;
4959         sb->s_magic = le16_to_cpu(es->s_magic);
4960         if (sb->s_magic != EXT4_SUPER_MAGIC) {
4961                 if (!silent)
4962                         ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4963                 goto out;
4964         }
4965
4966         if (le32_to_cpu(es->s_log_block_size) >
4967             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4968                 ext4_msg(sb, KERN_ERR,
4969                          "Invalid log block size: %u",
4970                          le32_to_cpu(es->s_log_block_size));
4971                 goto out;
4972         }
4973         if (le32_to_cpu(es->s_log_cluster_size) >
4974             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4975                 ext4_msg(sb, KERN_ERR,
4976                          "Invalid log cluster size: %u",
4977                          le32_to_cpu(es->s_log_cluster_size));
4978                 goto out;
4979         }
4980
4981         blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
4982
4983         /*
4984          * If the default block size is not the same as the real block size,
4985          * we need to reload it.
4986          */
4987         if (sb->s_blocksize == blocksize) {
4988                 *lsb = logical_sb_block;
4989                 sbi->s_sbh = bh;
4990                 return 0;
4991         }
4992
4993         /*
4994          * bh must be released before kill_bdev(), otherwise
4995          * it won't be freed and its page also. kill_bdev()
4996          * is called by sb_set_blocksize().
4997          */
4998         brelse(bh);
4999         /* Validate the filesystem blocksize */
5000         if (!sb_set_blocksize(sb, blocksize)) {
5001                 ext4_msg(sb, KERN_ERR, "bad block size %d",
5002                                 blocksize);
5003                 bh = NULL;
5004                 goto out;
5005         }
5006
5007         logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
5008         offset = do_div(logical_sb_block, blocksize);
5009         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
5010         if (IS_ERR(bh)) {
5011                 ext4_msg(sb, KERN_ERR, "Can't read superblock on 2nd try");
5012                 ret = PTR_ERR(bh);
5013                 bh = NULL;
5014                 goto out;
5015         }
5016         es = (struct ext4_super_block *)(bh->b_data + offset);
5017         sbi->s_es = es;
5018         if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
5019                 ext4_msg(sb, KERN_ERR, "Magic mismatch, very weird!");
5020                 goto out;
5021         }
5022         *lsb = logical_sb_block;
5023         sbi->s_sbh = bh;
5024         return 0;
5025 out:
5026         brelse(bh);
5027         return ret;
5028 }
5029
5030 static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
5031 {
5032         struct ext4_super_block *es = NULL;
5033         struct ext4_sb_info *sbi = EXT4_SB(sb);
5034         struct flex_groups **flex_groups;
5035         ext4_fsblk_t block;
5036         ext4_fsblk_t logical_sb_block;
5037         struct inode *root;
5038         int ret = -ENOMEM;
5039         unsigned int i;
5040         int needs_recovery, has_huge_files;
5041         int err = 0;
5042         ext4_group_t first_not_zeroed;
5043         struct ext4_fs_context *ctx = fc->fs_private;
5044         int silent = fc->sb_flags & SB_SILENT;
5045
5046         /* Set defaults for the variables that will be set during parsing */
5047         if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO))
5048                 ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5049
5050         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
5051         sbi->s_sectors_written_start =
5052                 part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
5053
5054         /* -EINVAL is default */
5055         ret = -EINVAL;
5056         err = ext4_load_super(sb, &logical_sb_block, silent);
5057         if (err)
5058                 goto out_fail;
5059
5060         es = sbi->s_es;
5061         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
5062
5063         err = ext4_init_metadata_csum(sb, es);
5064         if (err)
5065                 goto failed_mount;
5066
5067         ext4_set_def_opts(sb, es);
5068
5069         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
5070         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
5071         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
5072         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
5073         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
5074
5075         /*
5076          * set default s_li_wait_mult for lazyinit, for the case there is
5077          * no mount option specified.
5078          */
5079         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
5080
5081         if (ext4_inode_info_init(sb, es))
5082                 goto failed_mount;
5083
5084         err = parse_apply_sb_mount_options(sb, ctx);
5085         if (err < 0)
5086                 goto failed_mount;
5087
5088         sbi->s_def_mount_opt = sbi->s_mount_opt;
5089
5090         err = ext4_check_opt_consistency(fc, sb);
5091         if (err < 0)
5092                 goto failed_mount;
5093
5094         ext4_apply_options(fc, sb);
5095
5096         if (ext4_encoding_init(sb, es))
5097                 goto failed_mount;
5098
5099         if (ext4_journal_data_mode_check(sb))
5100                 goto failed_mount;
5101
5102         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5103                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5104
5105         /* i_version is always enabled now */
5106         sb->s_flags |= SB_I_VERSION;
5107
5108         if (ext4_check_feature_compatibility(sb, es, silent))
5109                 goto failed_mount;
5110
5111         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (sb->s_blocksize / 4)) {
5112                 ext4_msg(sb, KERN_ERR,
5113                          "Number of reserved GDT blocks insanely large: %d",
5114                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
5115                 goto failed_mount;
5116         }
5117
5118         if (sbi->s_daxdev) {
5119                 if (sb->s_blocksize == PAGE_SIZE)
5120                         set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
5121                 else
5122                         ext4_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
5123         }
5124
5125         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
5126                 if (ext4_has_feature_inline_data(sb)) {
5127                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
5128                                         " that may contain inline data");
5129                         goto failed_mount;
5130                 }
5131                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
5132                         ext4_msg(sb, KERN_ERR,
5133                                 "DAX unsupported by block device.");
5134                         goto failed_mount;
5135                 }
5136         }
5137
5138         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
5139                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
5140                          es->s_encryption_level);
5141                 goto failed_mount;
5142         }
5143
5144         has_huge_files = ext4_has_feature_huge_file(sb);
5145         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
5146                                                       has_huge_files);
5147         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
5148
5149         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
5150         if (ext4_has_feature_64bit(sb)) {
5151                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
5152                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
5153                     !is_power_of_2(sbi->s_desc_size)) {
5154                         ext4_msg(sb, KERN_ERR,
5155                                "unsupported descriptor size %lu",
5156                                sbi->s_desc_size);
5157                         goto failed_mount;
5158                 }
5159         } else
5160                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
5161
5162         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
5163         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
5164
5165         sbi->s_inodes_per_block = sb->s_blocksize / EXT4_INODE_SIZE(sb);
5166         if (sbi->s_inodes_per_block == 0 || sbi->s_blocks_per_group == 0) {
5167                 if (!silent)
5168                         ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5169                 goto failed_mount;
5170         }
5171         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
5172             sbi->s_inodes_per_group > sb->s_blocksize * 8) {
5173                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
5174                          sbi->s_inodes_per_group);
5175                 goto failed_mount;
5176         }
5177         sbi->s_itb_per_group = sbi->s_inodes_per_group /
5178                                         sbi->s_inodes_per_block;
5179         sbi->s_desc_per_block = sb->s_blocksize / EXT4_DESC_SIZE(sb);
5180         sbi->s_mount_state = le16_to_cpu(es->s_state) & ~EXT4_FC_REPLAY;
5181         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
5182         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
5183
5184         for (i = 0; i < 4; i++)
5185                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
5186         sbi->s_def_hash_version = es->s_def_hash_version;
5187         if (ext4_has_feature_dir_index(sb)) {
5188                 i = le32_to_cpu(es->s_flags);
5189                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
5190                         sbi->s_hash_unsigned = 3;
5191                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
5192 #ifdef __CHAR_UNSIGNED__
5193                         if (!sb_rdonly(sb))
5194                                 es->s_flags |=
5195                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
5196                         sbi->s_hash_unsigned = 3;
5197 #else
5198                         if (!sb_rdonly(sb))
5199                                 es->s_flags |=
5200                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
5201 #endif
5202                 }
5203         }
5204
5205         if (ext4_handle_clustersize(sb))
5206                 goto failed_mount;
5207
5208         /*
5209          * Test whether we have more sectors than will fit in sector_t,
5210          * and whether the max offset is addressable by the page cache.
5211          */
5212         err = generic_check_addressable(sb->s_blocksize_bits,
5213                                         ext4_blocks_count(es));
5214         if (err) {
5215                 ext4_msg(sb, KERN_ERR, "filesystem"
5216                          " too large to mount safely on this system");
5217                 goto failed_mount;
5218         }
5219
5220         if (ext4_geometry_check(sb, es))
5221                 goto failed_mount;
5222
5223         err = ext4_group_desc_init(sb, es, logical_sb_block, &first_not_zeroed);
5224         if (err)
5225                 goto failed_mount;
5226
5227         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
5228         spin_lock_init(&sbi->s_error_lock);
5229         INIT_WORK(&sbi->s_error_work, flush_stashed_error_work);
5230
5231         /* Register extent status tree shrinker */
5232         if (ext4_es_register_shrinker(sbi))
5233                 goto failed_mount3;
5234
5235         sbi->s_stripe = ext4_get_stripe_size(sbi);
5236         sbi->s_extent_max_zeroout_kb = 32;
5237
5238         /*
5239          * set up enough so that it can read an inode
5240          */
5241         sb->s_op = &ext4_sops;
5242         sb->s_export_op = &ext4_export_ops;
5243         sb->s_xattr = ext4_xattr_handlers;
5244 #ifdef CONFIG_FS_ENCRYPTION
5245         sb->s_cop = &ext4_cryptops;
5246 #endif
5247 #ifdef CONFIG_FS_VERITY
5248         sb->s_vop = &ext4_verityops;
5249 #endif
5250 #ifdef CONFIG_QUOTA
5251         sb->dq_op = &ext4_quota_operations;
5252         if (ext4_has_feature_quota(sb))
5253                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
5254         else
5255                 sb->s_qcop = &ext4_qctl_operations;
5256         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
5257 #endif
5258         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
5259
5260         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
5261         mutex_init(&sbi->s_orphan_lock);
5262
5263         ext4_fast_commit_init(sb);
5264
5265         sb->s_root = NULL;
5266
5267         needs_recovery = (es->s_last_orphan != 0 ||
5268                           ext4_has_feature_orphan_present(sb) ||
5269                           ext4_has_feature_journal_needs_recovery(sb));
5270
5271         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
5272                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
5273                         goto failed_mount3a;
5274
5275         /*
5276          * The first inode we look at is the journal inode.  Don't try
5277          * root first: it may be modified in the journal!
5278          */
5279         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
5280                 err = ext4_load_and_init_journal(sb, es, ctx);
5281                 if (err)
5282                         goto failed_mount3a;
5283         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
5284                    ext4_has_feature_journal_needs_recovery(sb)) {
5285                 ext4_msg(sb, KERN_ERR, "required journal recovery "
5286                        "suppressed and not mounted read-only");
5287                 goto failed_mount3a;
5288         } else {
5289                 /* Nojournal mode, all journal mount options are illegal */
5290                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
5291                         ext4_msg(sb, KERN_ERR, "can't mount with "
5292                                  "journal_checksum, fs mounted w/o journal");
5293                         goto failed_mount3a;
5294                 }
5295                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5296                         ext4_msg(sb, KERN_ERR, "can't mount with "
5297                                  "journal_async_commit, fs mounted w/o journal");
5298                         goto failed_mount3a;
5299                 }
5300                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
5301                         ext4_msg(sb, KERN_ERR, "can't mount with "
5302                                  "commit=%lu, fs mounted w/o journal",
5303                                  sbi->s_commit_interval / HZ);
5304                         goto failed_mount3a;
5305                 }
5306                 if (EXT4_MOUNT_DATA_FLAGS &
5307                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
5308                         ext4_msg(sb, KERN_ERR, "can't mount with "
5309                                  "data=, fs mounted w/o journal");
5310                         goto failed_mount3a;
5311                 }
5312                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
5313                 clear_opt(sb, JOURNAL_CHECKSUM);
5314                 clear_opt(sb, DATA_FLAGS);
5315                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
5316                 sbi->s_journal = NULL;
5317                 needs_recovery = 0;
5318         }
5319
5320         if (!test_opt(sb, NO_MBCACHE)) {
5321                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
5322                 if (!sbi->s_ea_block_cache) {
5323                         ext4_msg(sb, KERN_ERR,
5324                                  "Failed to create ea_block_cache");
5325                         goto failed_mount_wq;
5326                 }
5327
5328                 if (ext4_has_feature_ea_inode(sb)) {
5329                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
5330                         if (!sbi->s_ea_inode_cache) {
5331                                 ext4_msg(sb, KERN_ERR,
5332                                          "Failed to create ea_inode_cache");
5333                                 goto failed_mount_wq;
5334                         }
5335                 }
5336         }
5337
5338         if (ext4_has_feature_verity(sb) && sb->s_blocksize != PAGE_SIZE) {
5339                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
5340                 goto failed_mount_wq;
5341         }
5342
5343         /*
5344          * Get the # of file system overhead blocks from the
5345          * superblock if present.
5346          */
5347         sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
5348         /* ignore the precalculated value if it is ridiculous */
5349         if (sbi->s_overhead > ext4_blocks_count(es))
5350                 sbi->s_overhead = 0;
5351         /*
5352          * If the bigalloc feature is not enabled recalculating the
5353          * overhead doesn't take long, so we might as well just redo
5354          * it to make sure we are using the correct value.
5355          */
5356         if (!ext4_has_feature_bigalloc(sb))
5357                 sbi->s_overhead = 0;
5358         if (sbi->s_overhead == 0) {
5359                 err = ext4_calculate_overhead(sb);
5360                 if (err)
5361                         goto failed_mount_wq;
5362         }
5363
5364         /*
5365          * The maximum number of concurrent works can be high and
5366          * concurrency isn't really necessary.  Limit it to 1.
5367          */
5368         EXT4_SB(sb)->rsv_conversion_wq =
5369                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
5370         if (!EXT4_SB(sb)->rsv_conversion_wq) {
5371                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
5372                 ret = -ENOMEM;
5373                 goto failed_mount4;
5374         }
5375
5376         /*
5377          * The jbd2_journal_load will have done any necessary log recovery,
5378          * so we can safely mount the rest of the filesystem now.
5379          */
5380
5381         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
5382         if (IS_ERR(root)) {
5383                 ext4_msg(sb, KERN_ERR, "get root inode failed");
5384                 ret = PTR_ERR(root);
5385                 root = NULL;
5386                 goto failed_mount4;
5387         }
5388         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
5389                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
5390                 iput(root);
5391                 goto failed_mount4;
5392         }
5393
5394         sb->s_root = d_make_root(root);
5395         if (!sb->s_root) {
5396                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
5397                 ret = -ENOMEM;
5398                 goto failed_mount4;
5399         }
5400
5401         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
5402         if (ret == -EROFS) {
5403                 sb->s_flags |= SB_RDONLY;
5404                 ret = 0;
5405         } else if (ret)
5406                 goto failed_mount4a;
5407
5408         ext4_set_resv_clusters(sb);
5409
5410         if (test_opt(sb, BLOCK_VALIDITY)) {
5411                 err = ext4_setup_system_zone(sb);
5412                 if (err) {
5413                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
5414                                  "zone (%d)", err);
5415                         goto failed_mount4a;
5416                 }
5417         }
5418         ext4_fc_replay_cleanup(sb);
5419
5420         ext4_ext_init(sb);
5421
5422         /*
5423          * Enable optimize_scan if number of groups is > threshold. This can be
5424          * turned off by passing "mb_optimize_scan=0". This can also be
5425          * turned on forcefully by passing "mb_optimize_scan=1".
5426          */
5427         if (!(ctx->spec & EXT4_SPEC_mb_optimize_scan)) {
5428                 if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
5429                         set_opt2(sb, MB_OPTIMIZE_SCAN);
5430                 else
5431                         clear_opt2(sb, MB_OPTIMIZE_SCAN);
5432         }
5433
5434         err = ext4_mb_init(sb);
5435         if (err) {
5436                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5437                          err);
5438                 goto failed_mount5;
5439         }
5440
5441         /*
5442          * We can only set up the journal commit callback once
5443          * mballoc is initialized
5444          */
5445         if (sbi->s_journal)
5446                 sbi->s_journal->j_commit_callback =
5447                         ext4_journal_commit_callback;
5448
5449         block = ext4_count_free_clusters(sb);
5450         ext4_free_blocks_count_set(sbi->s_es,
5451                                    EXT4_C2B(sbi, block));
5452         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
5453                                   GFP_KERNEL);
5454         if (!err) {
5455                 unsigned long freei = ext4_count_free_inodes(sb);
5456                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
5457                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
5458                                           GFP_KERNEL);
5459         }
5460         if (!err)
5461                 err = percpu_counter_init(&sbi->s_dirs_counter,
5462                                           ext4_count_dirs(sb), GFP_KERNEL);
5463         if (!err)
5464                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
5465                                           GFP_KERNEL);
5466         if (!err)
5467                 err = percpu_counter_init(&sbi->s_sra_exceeded_retry_limit, 0,
5468                                           GFP_KERNEL);
5469         if (!err)
5470                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
5471
5472         if (err) {
5473                 ext4_msg(sb, KERN_ERR, "insufficient memory");
5474                 goto failed_mount6;
5475         }
5476
5477         if (ext4_has_feature_flex_bg(sb))
5478                 if (!ext4_fill_flex_info(sb)) {
5479                         ext4_msg(sb, KERN_ERR,
5480                                "unable to initialize "
5481                                "flex_bg meta info!");
5482                         ret = -ENOMEM;
5483                         goto failed_mount6;
5484                 }
5485
5486         err = ext4_register_li_request(sb, first_not_zeroed);
5487         if (err)
5488                 goto failed_mount6;
5489
5490         err = ext4_register_sysfs(sb);
5491         if (err)
5492                 goto failed_mount7;
5493
5494         err = ext4_init_orphan_info(sb);
5495         if (err)
5496                 goto failed_mount8;
5497 #ifdef CONFIG_QUOTA
5498         /* Enable quota usage during mount. */
5499         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5500                 err = ext4_enable_quotas(sb);
5501                 if (err)
5502                         goto failed_mount9;
5503         }
5504 #endif  /* CONFIG_QUOTA */
5505
5506         /*
5507          * Save the original bdev mapping's wb_err value which could be
5508          * used to detect the metadata async write error.
5509          */
5510         spin_lock_init(&sbi->s_bdev_wb_lock);
5511         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5512                                  &sbi->s_bdev_wb_err);
5513         sb->s_bdev->bd_super = sb;
5514         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5515         ext4_orphan_cleanup(sb, es);
5516         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5517         /*
5518          * Update the checksum after updating free space/inode counters and
5519          * ext4_orphan_cleanup. Otherwise the superblock can have an incorrect
5520          * checksum in the buffer cache until it is written out and
5521          * e2fsprogs programs trying to open a file system immediately
5522          * after it is mounted can fail.
5523          */
5524         ext4_superblock_csum_set(sb);
5525         if (needs_recovery) {
5526                 ext4_msg(sb, KERN_INFO, "recovery complete");
5527                 err = ext4_mark_recovery_complete(sb, es);
5528                 if (err)
5529                         goto failed_mount9;
5530         }
5531
5532         if (test_opt(sb, DISCARD) && !bdev_max_discard_sectors(sb->s_bdev))
5533                 ext4_msg(sb, KERN_WARNING,
5534                          "mounting with \"discard\" option, but the device does not support discard");
5535
5536         if (es->s_error_count)
5537                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5538
5539         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5540         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5541         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5542         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5543         atomic_set(&sbi->s_warning_count, 0);
5544         atomic_set(&sbi->s_msg_count, 0);
5545
5546         return 0;
5547
5548 failed_mount9:
5549         ext4_release_orphan_info(sb);
5550 failed_mount8:
5551         ext4_unregister_sysfs(sb);
5552         kobject_put(&sbi->s_kobj);
5553 failed_mount7:
5554         ext4_unregister_li_request(sb);
5555 failed_mount6:
5556         ext4_mb_release(sb);
5557         rcu_read_lock();
5558         flex_groups = rcu_dereference(sbi->s_flex_groups);
5559         if (flex_groups) {
5560                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
5561                         kvfree(flex_groups[i]);
5562                 kvfree(flex_groups);
5563         }
5564         rcu_read_unlock();
5565         percpu_counter_destroy(&sbi->s_freeclusters_counter);
5566         percpu_counter_destroy(&sbi->s_freeinodes_counter);
5567         percpu_counter_destroy(&sbi->s_dirs_counter);
5568         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
5569         percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
5570         percpu_free_rwsem(&sbi->s_writepages_rwsem);
5571 failed_mount5:
5572         ext4_ext_release(sb);
5573         ext4_release_system_zone(sb);
5574 failed_mount4a:
5575         dput(sb->s_root);
5576         sb->s_root = NULL;
5577 failed_mount4:
5578         ext4_msg(sb, KERN_ERR, "mount failed");
5579         if (EXT4_SB(sb)->rsv_conversion_wq)
5580                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5581 failed_mount_wq:
5582         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5583         sbi->s_ea_inode_cache = NULL;
5584
5585         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5586         sbi->s_ea_block_cache = NULL;
5587
5588         if (sbi->s_journal) {
5589                 /* flush s_error_work before journal destroy. */
5590                 flush_work(&sbi->s_error_work);
5591                 jbd2_journal_destroy(sbi->s_journal);
5592                 sbi->s_journal = NULL;
5593         }
5594 failed_mount3a:
5595         ext4_es_unregister_shrinker(sbi);
5596 failed_mount3:
5597         /* flush s_error_work before sbi destroy */
5598         flush_work(&sbi->s_error_work);
5599         del_timer_sync(&sbi->s_err_report);
5600         ext4_stop_mmpd(sbi);
5601         ext4_group_desc_free(sbi);
5602 failed_mount:
5603         if (sbi->s_chksum_driver)
5604                 crypto_free_shash(sbi->s_chksum_driver);
5605
5606 #if IS_ENABLED(CONFIG_UNICODE)
5607         utf8_unload(sb->s_encoding);
5608 #endif
5609
5610 #ifdef CONFIG_QUOTA
5611         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5612                 kfree(get_qf_name(sb, sbi, i));
5613 #endif
5614         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5615         /* ext4_blkdev_remove() calls kill_bdev(), release bh before it. */
5616         brelse(sbi->s_sbh);
5617         ext4_blkdev_remove(sbi);
5618 out_fail:
5619         sb->s_fs_info = NULL;
5620         return err ? err : ret;
5621 }
5622
5623 static int ext4_fill_super(struct super_block *sb, struct fs_context *fc)
5624 {
5625         struct ext4_fs_context *ctx = fc->fs_private;
5626         struct ext4_sb_info *sbi;
5627         const char *descr;
5628         int ret;
5629
5630         sbi = ext4_alloc_sbi(sb);
5631         if (!sbi)
5632                 return -ENOMEM;
5633
5634         fc->s_fs_info = sbi;
5635
5636         /* Cleanup superblock name */
5637         strreplace(sb->s_id, '/', '!');
5638
5639         sbi->s_sb_block = 1;    /* Default super block location */
5640         if (ctx->spec & EXT4_SPEC_s_sb_block)
5641                 sbi->s_sb_block = ctx->s_sb_block;
5642
5643         ret = __ext4_fill_super(fc, sb);
5644         if (ret < 0)
5645                 goto free_sbi;
5646
5647         if (sbi->s_journal) {
5648                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5649                         descr = " journalled data mode";
5650                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5651                         descr = " ordered data mode";
5652                 else
5653                         descr = " writeback data mode";
5654         } else
5655                 descr = "out journal";
5656
5657         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5658                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
5659                          "Quota mode: %s.", descr, ext4_quota_mode(sb));
5660
5661         /* Update the s_overhead_clusters if necessary */
5662         ext4_update_overhead(sb, false);
5663         return 0;
5664
5665 free_sbi:
5666         ext4_free_sbi(sbi);
5667         fc->s_fs_info = NULL;
5668         return ret;
5669 }
5670
5671 static int ext4_get_tree(struct fs_context *fc)
5672 {
5673         return get_tree_bdev(fc, ext4_fill_super);
5674 }
5675
5676 /*
5677  * Setup any per-fs journal parameters now.  We'll do this both on
5678  * initial mount, once the journal has been initialised but before we've
5679  * done any recovery; and again on any subsequent remount.
5680  */
5681 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5682 {
5683         struct ext4_sb_info *sbi = EXT4_SB(sb);
5684
5685         journal->j_commit_interval = sbi->s_commit_interval;
5686         journal->j_min_batch_time = sbi->s_min_batch_time;
5687         journal->j_max_batch_time = sbi->s_max_batch_time;
5688         ext4_fc_init(sb, journal);
5689
5690         write_lock(&journal->j_state_lock);
5691         if (test_opt(sb, BARRIER))
5692                 journal->j_flags |= JBD2_BARRIER;
5693         else
5694                 journal->j_flags &= ~JBD2_BARRIER;
5695         if (test_opt(sb, DATA_ERR_ABORT))
5696                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5697         else
5698                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5699         write_unlock(&journal->j_state_lock);
5700 }
5701
5702 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5703                                              unsigned int journal_inum)
5704 {
5705         struct inode *journal_inode;
5706
5707         /*
5708          * Test for the existence of a valid inode on disk.  Bad things
5709          * happen if we iget() an unused inode, as the subsequent iput()
5710          * will try to delete it.
5711          */
5712         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5713         if (IS_ERR(journal_inode)) {
5714                 ext4_msg(sb, KERN_ERR, "no journal found");
5715                 return NULL;
5716         }
5717         if (!journal_inode->i_nlink) {
5718                 make_bad_inode(journal_inode);
5719                 iput(journal_inode);
5720                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5721                 return NULL;
5722         }
5723
5724         ext4_debug("Journal inode found at %p: %lld bytes\n",
5725                   journal_inode, journal_inode->i_size);
5726         if (!S_ISREG(journal_inode->i_mode)) {
5727                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5728                 iput(journal_inode);
5729                 return NULL;
5730         }
5731         return journal_inode;
5732 }
5733
5734 static journal_t *ext4_get_journal(struct super_block *sb,
5735                                    unsigned int journal_inum)
5736 {
5737         struct inode *journal_inode;
5738         journal_t *journal;
5739
5740         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5741                 return NULL;
5742
5743         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5744         if (!journal_inode)
5745                 return NULL;
5746
5747         journal = jbd2_journal_init_inode(journal_inode);
5748         if (!journal) {
5749                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5750                 iput(journal_inode);
5751                 return NULL;
5752         }
5753         journal->j_private = sb;
5754         ext4_init_journal_params(sb, journal);
5755         return journal;
5756 }
5757
5758 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5759                                        dev_t j_dev)
5760 {
5761         struct buffer_head *bh;
5762         journal_t *journal;
5763         ext4_fsblk_t start;
5764         ext4_fsblk_t len;
5765         int hblock, blocksize;
5766         ext4_fsblk_t sb_block;
5767         unsigned long offset;
5768         struct ext4_super_block *es;
5769         struct block_device *bdev;
5770
5771         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5772                 return NULL;
5773
5774         bdev = ext4_blkdev_get(j_dev, sb);
5775         if (bdev == NULL)
5776                 return NULL;
5777
5778         blocksize = sb->s_blocksize;
5779         hblock = bdev_logical_block_size(bdev);
5780         if (blocksize < hblock) {
5781                 ext4_msg(sb, KERN_ERR,
5782                         "blocksize too small for journal device");
5783                 goto out_bdev;
5784         }
5785
5786         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5787         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5788         set_blocksize(bdev, blocksize);
5789         if (!(bh = __bread(bdev, sb_block, blocksize))) {
5790                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5791                        "external journal");
5792                 goto out_bdev;
5793         }
5794
5795         es = (struct ext4_super_block *) (bh->b_data + offset);
5796         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5797             !(le32_to_cpu(es->s_feature_incompat) &
5798               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5799                 ext4_msg(sb, KERN_ERR, "external journal has "
5800                                         "bad superblock");
5801                 brelse(bh);
5802                 goto out_bdev;
5803         }
5804
5805         if ((le32_to_cpu(es->s_feature_ro_compat) &
5806              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5807             es->s_checksum != ext4_superblock_csum(sb, es)) {
5808                 ext4_msg(sb, KERN_ERR, "external journal has "
5809                                        "corrupt superblock");
5810                 brelse(bh);
5811                 goto out_bdev;
5812         }
5813
5814         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5815                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5816                 brelse(bh);
5817                 goto out_bdev;
5818         }
5819
5820         len = ext4_blocks_count(es);
5821         start = sb_block + 1;
5822         brelse(bh);     /* we're done with the superblock */
5823
5824         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5825                                         start, len, blocksize);
5826         if (!journal) {
5827                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5828                 goto out_bdev;
5829         }
5830         journal->j_private = sb;
5831         if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
5832                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5833                 goto out_journal;
5834         }
5835         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5836                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5837                                         "user (unsupported) - %d",
5838                         be32_to_cpu(journal->j_superblock->s_nr_users));
5839                 goto out_journal;
5840         }
5841         EXT4_SB(sb)->s_journal_bdev = bdev;
5842         ext4_init_journal_params(sb, journal);
5843         return journal;
5844
5845 out_journal:
5846         jbd2_journal_destroy(journal);
5847 out_bdev:
5848         ext4_blkdev_put(bdev);
5849         return NULL;
5850 }
5851
5852 static int ext4_load_journal(struct super_block *sb,
5853                              struct ext4_super_block *es,
5854                              unsigned long journal_devnum)
5855 {
5856         journal_t *journal;
5857         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5858         dev_t journal_dev;
5859         int err = 0;
5860         int really_read_only;
5861         int journal_dev_ro;
5862
5863         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5864                 return -EFSCORRUPTED;
5865
5866         if (journal_devnum &&
5867             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5868                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5869                         "numbers have changed");
5870                 journal_dev = new_decode_dev(journal_devnum);
5871         } else
5872                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5873
5874         if (journal_inum && journal_dev) {
5875                 ext4_msg(sb, KERN_ERR,
5876                          "filesystem has both journal inode and journal device!");
5877                 return -EINVAL;
5878         }
5879
5880         if (journal_inum) {
5881                 journal = ext4_get_journal(sb, journal_inum);
5882                 if (!journal)
5883                         return -EINVAL;
5884         } else {
5885                 journal = ext4_get_dev_journal(sb, journal_dev);
5886                 if (!journal)
5887                         return -EINVAL;
5888         }
5889
5890         journal_dev_ro = bdev_read_only(journal->j_dev);
5891         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5892
5893         if (journal_dev_ro && !sb_rdonly(sb)) {
5894                 ext4_msg(sb, KERN_ERR,
5895                          "journal device read-only, try mounting with '-o ro'");
5896                 err = -EROFS;
5897                 goto err_out;
5898         }
5899
5900         /*
5901          * Are we loading a blank journal or performing recovery after a
5902          * crash?  For recovery, we need to check in advance whether we
5903          * can get read-write access to the device.
5904          */
5905         if (ext4_has_feature_journal_needs_recovery(sb)) {
5906                 if (sb_rdonly(sb)) {
5907                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5908                                         "required on readonly filesystem");
5909                         if (really_read_only) {
5910                                 ext4_msg(sb, KERN_ERR, "write access "
5911                                         "unavailable, cannot proceed "
5912                                         "(try mounting with noload)");
5913                                 err = -EROFS;
5914                                 goto err_out;
5915                         }
5916                         ext4_msg(sb, KERN_INFO, "write access will "
5917                                "be enabled during recovery");
5918                 }
5919         }
5920
5921         if (!(journal->j_flags & JBD2_BARRIER))
5922                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5923
5924         if (!ext4_has_feature_journal_needs_recovery(sb))
5925                 err = jbd2_journal_wipe(journal, !really_read_only);
5926         if (!err) {
5927                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5928                 if (save)
5929                         memcpy(save, ((char *) es) +
5930                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5931                 err = jbd2_journal_load(journal);
5932                 if (save)
5933                         memcpy(((char *) es) + EXT4_S_ERR_START,
5934                                save, EXT4_S_ERR_LEN);
5935                 kfree(save);
5936         }
5937
5938         if (err) {
5939                 ext4_msg(sb, KERN_ERR, "error loading journal");
5940                 goto err_out;
5941         }
5942
5943         EXT4_SB(sb)->s_journal = journal;
5944         err = ext4_clear_journal_err(sb, es);
5945         if (err) {
5946                 EXT4_SB(sb)->s_journal = NULL;
5947                 jbd2_journal_destroy(journal);
5948                 return err;
5949         }
5950
5951         if (!really_read_only && journal_devnum &&
5952             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5953                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5954
5955                 /* Make sure we flush the recovery flag to disk. */
5956                 ext4_commit_super(sb);
5957         }
5958
5959         return 0;
5960
5961 err_out:
5962         jbd2_journal_destroy(journal);
5963         return err;
5964 }
5965
5966 /* Copy state of EXT4_SB(sb) into buffer for on-disk superblock */
5967 static void ext4_update_super(struct super_block *sb)
5968 {
5969         struct ext4_sb_info *sbi = EXT4_SB(sb);
5970         struct ext4_super_block *es = sbi->s_es;
5971         struct buffer_head *sbh = sbi->s_sbh;
5972
5973         lock_buffer(sbh);
5974         /*
5975          * If the file system is mounted read-only, don't update the
5976          * superblock write time.  This avoids updating the superblock
5977          * write time when we are mounting the root file system
5978          * read/only but we need to replay the journal; at that point,
5979          * for people who are east of GMT and who make their clock
5980          * tick in localtime for Windows bug-for-bug compatibility,
5981          * the clock is set in the future, and this will cause e2fsck
5982          * to complain and force a full file system check.
5983          */
5984         if (!(sb->s_flags & SB_RDONLY))
5985                 ext4_update_tstamp(es, s_wtime);
5986         es->s_kbytes_written =
5987                 cpu_to_le64(sbi->s_kbytes_written +
5988                     ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
5989                       sbi->s_sectors_written_start) >> 1));
5990         if (percpu_counter_initialized(&sbi->s_freeclusters_counter))
5991                 ext4_free_blocks_count_set(es,
5992                         EXT4_C2B(sbi, percpu_counter_sum_positive(
5993                                 &sbi->s_freeclusters_counter)));
5994         if (percpu_counter_initialized(&sbi->s_freeinodes_counter))
5995                 es->s_free_inodes_count =
5996                         cpu_to_le32(percpu_counter_sum_positive(
5997                                 &sbi->s_freeinodes_counter));
5998         /* Copy error information to the on-disk superblock */
5999         spin_lock(&sbi->s_error_lock);
6000         if (sbi->s_add_error_count > 0) {
6001                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6002                 if (!es->s_first_error_time && !es->s_first_error_time_hi) {
6003                         __ext4_update_tstamp(&es->s_first_error_time,
6004                                              &es->s_first_error_time_hi,
6005                                              sbi->s_first_error_time);
6006                         strncpy(es->s_first_error_func, sbi->s_first_error_func,
6007                                 sizeof(es->s_first_error_func));
6008                         es->s_first_error_line =
6009                                 cpu_to_le32(sbi->s_first_error_line);
6010                         es->s_first_error_ino =
6011                                 cpu_to_le32(sbi->s_first_error_ino);
6012                         es->s_first_error_block =
6013                                 cpu_to_le64(sbi->s_first_error_block);
6014                         es->s_first_error_errcode =
6015                                 ext4_errno_to_code(sbi->s_first_error_code);
6016                 }
6017                 __ext4_update_tstamp(&es->s_last_error_time,
6018                                      &es->s_last_error_time_hi,
6019                                      sbi->s_last_error_time);
6020                 strncpy(es->s_last_error_func, sbi->s_last_error_func,
6021                         sizeof(es->s_last_error_func));
6022                 es->s_last_error_line = cpu_to_le32(sbi->s_last_error_line);
6023                 es->s_last_error_ino = cpu_to_le32(sbi->s_last_error_ino);
6024                 es->s_last_error_block = cpu_to_le64(sbi->s_last_error_block);
6025                 es->s_last_error_errcode =
6026                                 ext4_errno_to_code(sbi->s_last_error_code);
6027                 /*
6028                  * Start the daily error reporting function if it hasn't been
6029                  * started already
6030                  */
6031                 if (!es->s_error_count)
6032                         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
6033                 le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
6034                 sbi->s_add_error_count = 0;
6035         }
6036         spin_unlock(&sbi->s_error_lock);
6037
6038         ext4_superblock_csum_set(sb);
6039         unlock_buffer(sbh);
6040 }
6041
6042 static int ext4_commit_super(struct super_block *sb)
6043 {
6044         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
6045
6046         if (!sbh)
6047                 return -EINVAL;
6048         if (block_device_ejected(sb))
6049                 return -ENODEV;
6050
6051         ext4_update_super(sb);
6052
6053         lock_buffer(sbh);
6054         /* Buffer got discarded which means block device got invalidated */
6055         if (!buffer_mapped(sbh)) {
6056                 unlock_buffer(sbh);
6057                 return -EIO;
6058         }
6059
6060         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
6061                 /*
6062                  * Oh, dear.  A previous attempt to write the
6063                  * superblock failed.  This could happen because the
6064                  * USB device was yanked out.  Or it could happen to
6065                  * be a transient write error and maybe the block will
6066                  * be remapped.  Nothing we can do but to retry the
6067                  * write and hope for the best.
6068                  */
6069                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
6070                        "superblock detected");
6071                 clear_buffer_write_io_error(sbh);
6072                 set_buffer_uptodate(sbh);
6073         }
6074         get_bh(sbh);
6075         /* Clear potential dirty bit if it was journalled update */
6076         clear_buffer_dirty(sbh);
6077         sbh->b_end_io = end_buffer_write_sync;
6078         submit_bh(REQ_OP_WRITE | REQ_SYNC |
6079                   (test_opt(sb, BARRIER) ? REQ_FUA : 0), sbh);
6080         wait_on_buffer(sbh);
6081         if (buffer_write_io_error(sbh)) {
6082                 ext4_msg(sb, KERN_ERR, "I/O error while writing "
6083                        "superblock");
6084                 clear_buffer_write_io_error(sbh);
6085                 set_buffer_uptodate(sbh);
6086                 return -EIO;
6087         }
6088         return 0;
6089 }
6090
6091 /*
6092  * Have we just finished recovery?  If so, and if we are mounting (or
6093  * remounting) the filesystem readonly, then we will end up with a
6094  * consistent fs on disk.  Record that fact.
6095  */
6096 static int ext4_mark_recovery_complete(struct super_block *sb,
6097                                        struct ext4_super_block *es)
6098 {
6099         int err;
6100         journal_t *journal = EXT4_SB(sb)->s_journal;
6101
6102         if (!ext4_has_feature_journal(sb)) {
6103                 if (journal != NULL) {
6104                         ext4_error(sb, "Journal got removed while the fs was "
6105                                    "mounted!");
6106                         return -EFSCORRUPTED;
6107                 }
6108                 return 0;
6109         }
6110         jbd2_journal_lock_updates(journal);
6111         err = jbd2_journal_flush(journal, 0);
6112         if (err < 0)
6113                 goto out;
6114
6115         if (sb_rdonly(sb) && (ext4_has_feature_journal_needs_recovery(sb) ||
6116             ext4_has_feature_orphan_present(sb))) {
6117                 if (!ext4_orphan_file_empty(sb)) {
6118                         ext4_error(sb, "Orphan file not empty on read-only fs.");
6119                         err = -EFSCORRUPTED;
6120                         goto out;
6121                 }
6122                 ext4_clear_feature_journal_needs_recovery(sb);
6123                 ext4_clear_feature_orphan_present(sb);
6124                 ext4_commit_super(sb);
6125         }
6126 out:
6127         jbd2_journal_unlock_updates(journal);
6128         return err;
6129 }
6130
6131 /*
6132  * If we are mounting (or read-write remounting) a filesystem whose journal
6133  * has recorded an error from a previous lifetime, move that error to the
6134  * main filesystem now.
6135  */
6136 static int ext4_clear_journal_err(struct super_block *sb,
6137                                    struct ext4_super_block *es)
6138 {
6139         journal_t *journal;
6140         int j_errno;
6141         const char *errstr;
6142
6143         if (!ext4_has_feature_journal(sb)) {
6144                 ext4_error(sb, "Journal got removed while the fs was mounted!");
6145                 return -EFSCORRUPTED;
6146         }
6147
6148         journal = EXT4_SB(sb)->s_journal;
6149
6150         /*
6151          * Now check for any error status which may have been recorded in the
6152          * journal by a prior ext4_error() or ext4_abort()
6153          */
6154
6155         j_errno = jbd2_journal_errno(journal);
6156         if (j_errno) {
6157                 char nbuf[16];
6158
6159                 errstr = ext4_decode_error(sb, j_errno, nbuf);
6160                 ext4_warning(sb, "Filesystem error recorded "
6161                              "from previous mount: %s", errstr);
6162                 ext4_warning(sb, "Marking fs in need of filesystem check.");
6163
6164                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
6165                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6166                 ext4_commit_super(sb);
6167
6168                 jbd2_journal_clear_err(journal);
6169                 jbd2_journal_update_sb_errno(journal);
6170         }
6171         return 0;
6172 }
6173
6174 /*
6175  * Force the running and committing transactions to commit,
6176  * and wait on the commit.
6177  */
6178 int ext4_force_commit(struct super_block *sb)
6179 {
6180         journal_t *journal;
6181
6182         if (sb_rdonly(sb))
6183                 return 0;
6184
6185         journal = EXT4_SB(sb)->s_journal;
6186         return ext4_journal_force_commit(journal);
6187 }
6188
6189 static int ext4_sync_fs(struct super_block *sb, int wait)
6190 {
6191         int ret = 0;
6192         tid_t target;
6193         bool needs_barrier = false;
6194         struct ext4_sb_info *sbi = EXT4_SB(sb);
6195
6196         if (unlikely(ext4_forced_shutdown(sbi)))
6197                 return 0;
6198
6199         trace_ext4_sync_fs(sb, wait);
6200         flush_workqueue(sbi->rsv_conversion_wq);
6201         /*
6202          * Writeback quota in non-journalled quota case - journalled quota has
6203          * no dirty dquots
6204          */
6205         dquot_writeback_dquots(sb, -1);
6206         /*
6207          * Data writeback is possible w/o journal transaction, so barrier must
6208          * being sent at the end of the function. But we can skip it if
6209          * transaction_commit will do it for us.
6210          */
6211         if (sbi->s_journal) {
6212                 target = jbd2_get_latest_transaction(sbi->s_journal);
6213                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
6214                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
6215                         needs_barrier = true;
6216
6217                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
6218                         if (wait)
6219                                 ret = jbd2_log_wait_commit(sbi->s_journal,
6220                                                            target);
6221                 }
6222         } else if (wait && test_opt(sb, BARRIER))
6223                 needs_barrier = true;
6224         if (needs_barrier) {
6225                 int err;
6226                 err = blkdev_issue_flush(sb->s_bdev);
6227                 if (!ret)
6228                         ret = err;
6229         }
6230
6231         return ret;
6232 }
6233
6234 /*
6235  * LVM calls this function before a (read-only) snapshot is created.  This
6236  * gives us a chance to flush the journal completely and mark the fs clean.
6237  *
6238  * Note that only this function cannot bring a filesystem to be in a clean
6239  * state independently. It relies on upper layer to stop all data & metadata
6240  * modifications.
6241  */
6242 static int ext4_freeze(struct super_block *sb)
6243 {
6244         int error = 0;
6245         journal_t *journal;
6246
6247         if (sb_rdonly(sb))
6248                 return 0;
6249
6250         journal = EXT4_SB(sb)->s_journal;
6251
6252         if (journal) {
6253                 /* Now we set up the journal barrier. */
6254                 jbd2_journal_lock_updates(journal);
6255
6256                 /*
6257                  * Don't clear the needs_recovery flag if we failed to
6258                  * flush the journal.
6259                  */
6260                 error = jbd2_journal_flush(journal, 0);
6261                 if (error < 0)
6262                         goto out;
6263
6264                 /* Journal blocked and flushed, clear needs_recovery flag. */
6265                 ext4_clear_feature_journal_needs_recovery(sb);
6266                 if (ext4_orphan_file_empty(sb))
6267                         ext4_clear_feature_orphan_present(sb);
6268         }
6269
6270         error = ext4_commit_super(sb);
6271 out:
6272         if (journal)
6273                 /* we rely on upper layer to stop further updates */
6274                 jbd2_journal_unlock_updates(journal);
6275         return error;
6276 }
6277
6278 /*
6279  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
6280  * flag here, even though the filesystem is not technically dirty yet.
6281  */
6282 static int ext4_unfreeze(struct super_block *sb)
6283 {
6284         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
6285                 return 0;
6286
6287         if (EXT4_SB(sb)->s_journal) {
6288                 /* Reset the needs_recovery flag before the fs is unlocked. */
6289                 ext4_set_feature_journal_needs_recovery(sb);
6290                 if (ext4_has_feature_orphan_file(sb))
6291                         ext4_set_feature_orphan_present(sb);
6292         }
6293
6294         ext4_commit_super(sb);
6295         return 0;
6296 }
6297
6298 /*
6299  * Structure to save mount options for ext4_remount's benefit
6300  */
6301 struct ext4_mount_options {
6302         unsigned long s_mount_opt;
6303         unsigned long s_mount_opt2;
6304         kuid_t s_resuid;
6305         kgid_t s_resgid;
6306         unsigned long s_commit_interval;
6307         u32 s_min_batch_time, s_max_batch_time;
6308 #ifdef CONFIG_QUOTA
6309         int s_jquota_fmt;
6310         char *s_qf_names[EXT4_MAXQUOTAS];
6311 #endif
6312 };
6313
6314 static int __ext4_remount(struct fs_context *fc, struct super_block *sb)
6315 {
6316         struct ext4_fs_context *ctx = fc->fs_private;
6317         struct ext4_super_block *es;
6318         struct ext4_sb_info *sbi = EXT4_SB(sb);
6319         unsigned long old_sb_flags;
6320         struct ext4_mount_options old_opts;
6321         ext4_group_t g;
6322         int err = 0;
6323 #ifdef CONFIG_QUOTA
6324         int enable_quota = 0;
6325         int i, j;
6326         char *to_free[EXT4_MAXQUOTAS];
6327 #endif
6328
6329
6330         /* Store the original options */
6331         old_sb_flags = sb->s_flags;
6332         old_opts.s_mount_opt = sbi->s_mount_opt;
6333         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
6334         old_opts.s_resuid = sbi->s_resuid;
6335         old_opts.s_resgid = sbi->s_resgid;
6336         old_opts.s_commit_interval = sbi->s_commit_interval;
6337         old_opts.s_min_batch_time = sbi->s_min_batch_time;
6338         old_opts.s_max_batch_time = sbi->s_max_batch_time;
6339 #ifdef CONFIG_QUOTA
6340         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
6341         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6342                 if (sbi->s_qf_names[i]) {
6343                         char *qf_name = get_qf_name(sb, sbi, i);
6344
6345                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
6346                         if (!old_opts.s_qf_names[i]) {
6347                                 for (j = 0; j < i; j++)
6348                                         kfree(old_opts.s_qf_names[j]);
6349                                 return -ENOMEM;
6350                         }
6351                 } else
6352                         old_opts.s_qf_names[i] = NULL;
6353 #endif
6354         if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)) {
6355                 if (sbi->s_journal && sbi->s_journal->j_task->io_context)
6356                         ctx->journal_ioprio =
6357                                 sbi->s_journal->j_task->io_context->ioprio;
6358                 else
6359                         ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
6360
6361         }
6362
6363         ext4_apply_options(fc, sb);
6364
6365         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
6366             test_opt(sb, JOURNAL_CHECKSUM)) {
6367                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
6368                          "during remount not supported; ignoring");
6369                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
6370         }
6371
6372         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
6373                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
6374                         ext4_msg(sb, KERN_ERR, "can't mount with "
6375                                  "both data=journal and delalloc");
6376                         err = -EINVAL;
6377                         goto restore_opts;
6378                 }
6379                 if (test_opt(sb, DIOREAD_NOLOCK)) {
6380                         ext4_msg(sb, KERN_ERR, "can't mount with "
6381                                  "both data=journal and dioread_nolock");
6382                         err = -EINVAL;
6383                         goto restore_opts;
6384                 }
6385         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
6386                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
6387                         ext4_msg(sb, KERN_ERR, "can't mount with "
6388                                 "journal_async_commit in data=ordered mode");
6389                         err = -EINVAL;
6390                         goto restore_opts;
6391                 }
6392         }
6393
6394         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
6395                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
6396                 err = -EINVAL;
6397                 goto restore_opts;
6398         }
6399
6400         if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED))
6401                 ext4_abort(sb, ESHUTDOWN, "Abort forced by user");
6402
6403         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
6404                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
6405
6406         es = sbi->s_es;
6407
6408         if (sbi->s_journal) {
6409                 ext4_init_journal_params(sb, sbi->s_journal);
6410                 set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
6411         }
6412
6413         /* Flush outstanding errors before changing fs state */
6414         flush_work(&sbi->s_error_work);
6415
6416         if ((bool)(fc->sb_flags & SB_RDONLY) != sb_rdonly(sb)) {
6417                 if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED)) {
6418                         err = -EROFS;
6419                         goto restore_opts;
6420                 }
6421
6422                 if (fc->sb_flags & SB_RDONLY) {
6423                         err = sync_filesystem(sb);
6424                         if (err < 0)
6425                                 goto restore_opts;
6426                         err = dquot_suspend(sb, -1);
6427                         if (err < 0)
6428                                 goto restore_opts;
6429
6430                         /*
6431                          * First of all, the unconditional stuff we have to do
6432                          * to disable replay of the journal when we next remount
6433                          */
6434                         sb->s_flags |= SB_RDONLY;
6435
6436                         /*
6437                          * OK, test if we are remounting a valid rw partition
6438                          * readonly, and if so set the rdonly flag and then
6439                          * mark the partition as valid again.
6440                          */
6441                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
6442                             (sbi->s_mount_state & EXT4_VALID_FS))
6443                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
6444
6445                         if (sbi->s_journal) {
6446                                 /*
6447                                  * We let remount-ro finish even if marking fs
6448                                  * as clean failed...
6449                                  */
6450                                 ext4_mark_recovery_complete(sb, es);
6451                         }
6452                 } else {
6453                         /* Make sure we can mount this feature set readwrite */
6454                         if (ext4_has_feature_readonly(sb) ||
6455                             !ext4_feature_set_ok(sb, 0)) {
6456                                 err = -EROFS;
6457                                 goto restore_opts;
6458                         }
6459                         /*
6460                          * Make sure the group descriptor checksums
6461                          * are sane.  If they aren't, refuse to remount r/w.
6462                          */
6463                         for (g = 0; g < sbi->s_groups_count; g++) {
6464                                 struct ext4_group_desc *gdp =
6465                                         ext4_get_group_desc(sb, g, NULL);
6466
6467                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
6468                                         ext4_msg(sb, KERN_ERR,
6469                "ext4_remount: Checksum for group %u failed (%u!=%u)",
6470                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
6471                                                le16_to_cpu(gdp->bg_checksum));
6472                                         err = -EFSBADCRC;
6473                                         goto restore_opts;
6474                                 }
6475                         }
6476
6477                         /*
6478                          * If we have an unprocessed orphan list hanging
6479                          * around from a previously readonly bdev mount,
6480                          * require a full umount/remount for now.
6481                          */
6482                         if (es->s_last_orphan || !ext4_orphan_file_empty(sb)) {
6483                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
6484                                        "remount RDWR because of unprocessed "
6485                                        "orphan inode list.  Please "
6486                                        "umount/remount instead");
6487                                 err = -EINVAL;
6488                                 goto restore_opts;
6489                         }
6490
6491                         /*
6492                          * Mounting a RDONLY partition read-write, so reread
6493                          * and store the current valid flag.  (It may have
6494                          * been changed by e2fsck since we originally mounted
6495                          * the partition.)
6496                          */
6497                         if (sbi->s_journal) {
6498                                 err = ext4_clear_journal_err(sb, es);
6499                                 if (err)
6500                                         goto restore_opts;
6501                         }
6502                         sbi->s_mount_state = (le16_to_cpu(es->s_state) &
6503                                               ~EXT4_FC_REPLAY);
6504
6505                         err = ext4_setup_super(sb, es, 0);
6506                         if (err)
6507                                 goto restore_opts;
6508
6509                         sb->s_flags &= ~SB_RDONLY;
6510                         if (ext4_has_feature_mmp(sb))
6511                                 if (ext4_multi_mount_protect(sb,
6512                                                 le64_to_cpu(es->s_mmp_block))) {
6513                                         err = -EROFS;
6514                                         goto restore_opts;
6515                                 }
6516 #ifdef CONFIG_QUOTA
6517                         enable_quota = 1;
6518 #endif
6519                 }
6520         }
6521
6522         /*
6523          * Reinitialize lazy itable initialization thread based on
6524          * current settings
6525          */
6526         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
6527                 ext4_unregister_li_request(sb);
6528         else {
6529                 ext4_group_t first_not_zeroed;
6530                 first_not_zeroed = ext4_has_uninit_itable(sb);
6531                 ext4_register_li_request(sb, first_not_zeroed);
6532         }
6533
6534         /*
6535          * Handle creation of system zone data early because it can fail.
6536          * Releasing of existing data is done when we are sure remount will
6537          * succeed.
6538          */
6539         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6540                 err = ext4_setup_system_zone(sb);
6541                 if (err)
6542                         goto restore_opts;
6543         }
6544
6545         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6546                 err = ext4_commit_super(sb);
6547                 if (err)
6548                         goto restore_opts;
6549         }
6550
6551 #ifdef CONFIG_QUOTA
6552         /* Release old quota file names */
6553         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6554                 kfree(old_opts.s_qf_names[i]);
6555         if (enable_quota) {
6556                 if (sb_any_quota_suspended(sb))
6557                         dquot_resume(sb, -1);
6558                 else if (ext4_has_feature_quota(sb)) {
6559                         err = ext4_enable_quotas(sb);
6560                         if (err)
6561                                 goto restore_opts;
6562                 }
6563         }
6564 #endif
6565         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6566                 ext4_release_system_zone(sb);
6567
6568         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6569                 ext4_stop_mmpd(sbi);
6570
6571         return 0;
6572
6573 restore_opts:
6574         sb->s_flags = old_sb_flags;
6575         sbi->s_mount_opt = old_opts.s_mount_opt;
6576         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6577         sbi->s_resuid = old_opts.s_resuid;
6578         sbi->s_resgid = old_opts.s_resgid;
6579         sbi->s_commit_interval = old_opts.s_commit_interval;
6580         sbi->s_min_batch_time = old_opts.s_min_batch_time;
6581         sbi->s_max_batch_time = old_opts.s_max_batch_time;
6582         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6583                 ext4_release_system_zone(sb);
6584 #ifdef CONFIG_QUOTA
6585         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6586         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6587                 to_free[i] = get_qf_name(sb, sbi, i);
6588                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6589         }
6590         synchronize_rcu();
6591         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6592                 kfree(to_free[i]);
6593 #endif
6594         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6595                 ext4_stop_mmpd(sbi);
6596         return err;
6597 }
6598
6599 static int ext4_reconfigure(struct fs_context *fc)
6600 {
6601         struct super_block *sb = fc->root->d_sb;
6602         int ret;
6603
6604         fc->s_fs_info = EXT4_SB(sb);
6605
6606         ret = ext4_check_opt_consistency(fc, sb);
6607         if (ret < 0)
6608                 return ret;
6609
6610         ret = __ext4_remount(fc, sb);
6611         if (ret < 0)
6612                 return ret;
6613
6614         ext4_msg(sb, KERN_INFO, "re-mounted. Quota mode: %s.",
6615                  ext4_quota_mode(sb));
6616
6617         return 0;
6618 }
6619
6620 #ifdef CONFIG_QUOTA
6621 static int ext4_statfs_project(struct super_block *sb,
6622                                kprojid_t projid, struct kstatfs *buf)
6623 {
6624         struct kqid qid;
6625         struct dquot *dquot;
6626         u64 limit;
6627         u64 curblock;
6628
6629         qid = make_kqid_projid(projid);
6630         dquot = dqget(sb, qid);
6631         if (IS_ERR(dquot))
6632                 return PTR_ERR(dquot);
6633         spin_lock(&dquot->dq_dqb_lock);
6634
6635         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6636                              dquot->dq_dqb.dqb_bhardlimit);
6637         limit >>= sb->s_blocksize_bits;
6638
6639         if (limit && buf->f_blocks > limit) {
6640                 curblock = (dquot->dq_dqb.dqb_curspace +
6641                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6642                 buf->f_blocks = limit;
6643                 buf->f_bfree = buf->f_bavail =
6644                         (buf->f_blocks > curblock) ?
6645                          (buf->f_blocks - curblock) : 0;
6646         }
6647
6648         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6649                              dquot->dq_dqb.dqb_ihardlimit);
6650         if (limit && buf->f_files > limit) {
6651                 buf->f_files = limit;
6652                 buf->f_ffree =
6653                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6654                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6655         }
6656
6657         spin_unlock(&dquot->dq_dqb_lock);
6658         dqput(dquot);
6659         return 0;
6660 }
6661 #endif
6662
6663 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6664 {
6665         struct super_block *sb = dentry->d_sb;
6666         struct ext4_sb_info *sbi = EXT4_SB(sb);
6667         struct ext4_super_block *es = sbi->s_es;
6668         ext4_fsblk_t overhead = 0, resv_blocks;
6669         s64 bfree;
6670         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6671
6672         if (!test_opt(sb, MINIX_DF))
6673                 overhead = sbi->s_overhead;
6674
6675         buf->f_type = EXT4_SUPER_MAGIC;
6676         buf->f_bsize = sb->s_blocksize;
6677         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6678         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6679                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6680         /* prevent underflow in case that few free space is available */
6681         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6682         buf->f_bavail = buf->f_bfree -
6683                         (ext4_r_blocks_count(es) + resv_blocks);
6684         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6685                 buf->f_bavail = 0;
6686         buf->f_files = le32_to_cpu(es->s_inodes_count);
6687         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6688         buf->f_namelen = EXT4_NAME_LEN;
6689         buf->f_fsid = uuid_to_fsid(es->s_uuid);
6690
6691 #ifdef CONFIG_QUOTA
6692         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6693             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6694                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6695 #endif
6696         return 0;
6697 }
6698
6699
6700 #ifdef CONFIG_QUOTA
6701
6702 /*
6703  * Helper functions so that transaction is started before we acquire dqio_sem
6704  * to keep correct lock ordering of transaction > dqio_sem
6705  */
6706 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6707 {
6708         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6709 }
6710
6711 static int ext4_write_dquot(struct dquot *dquot)
6712 {
6713         int ret, err;
6714         handle_t *handle;
6715         struct inode *inode;
6716
6717         inode = dquot_to_inode(dquot);
6718         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6719                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6720         if (IS_ERR(handle))
6721                 return PTR_ERR(handle);
6722         ret = dquot_commit(dquot);
6723         err = ext4_journal_stop(handle);
6724         if (!ret)
6725                 ret = err;
6726         return ret;
6727 }
6728
6729 static int ext4_acquire_dquot(struct dquot *dquot)
6730 {
6731         int ret, err;
6732         handle_t *handle;
6733
6734         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6735                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6736         if (IS_ERR(handle))
6737                 return PTR_ERR(handle);
6738         ret = dquot_acquire(dquot);
6739         err = ext4_journal_stop(handle);
6740         if (!ret)
6741                 ret = err;
6742         return ret;
6743 }
6744
6745 static int ext4_release_dquot(struct dquot *dquot)
6746 {
6747         int ret, err;
6748         handle_t *handle;
6749
6750         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6751                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6752         if (IS_ERR(handle)) {
6753                 /* Release dquot anyway to avoid endless cycle in dqput() */
6754                 dquot_release(dquot);
6755                 return PTR_ERR(handle);
6756         }
6757         ret = dquot_release(dquot);
6758         err = ext4_journal_stop(handle);
6759         if (!ret)
6760                 ret = err;
6761         return ret;
6762 }
6763
6764 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6765 {
6766         struct super_block *sb = dquot->dq_sb;
6767
6768         if (ext4_is_quota_journalled(sb)) {
6769                 dquot_mark_dquot_dirty(dquot);
6770                 return ext4_write_dquot(dquot);
6771         } else {
6772                 return dquot_mark_dquot_dirty(dquot);
6773         }
6774 }
6775
6776 static int ext4_write_info(struct super_block *sb, int type)
6777 {
6778         int ret, err;
6779         handle_t *handle;
6780
6781         /* Data block + inode block */
6782         handle = ext4_journal_start_sb(sb, EXT4_HT_QUOTA, 2);
6783         if (IS_ERR(handle))
6784                 return PTR_ERR(handle);
6785         ret = dquot_commit_info(sb, type);
6786         err = ext4_journal_stop(handle);
6787         if (!ret)
6788                 ret = err;
6789         return ret;
6790 }
6791
6792 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6793 {
6794         struct ext4_inode_info *ei = EXT4_I(inode);
6795
6796         /* The first argument of lockdep_set_subclass has to be
6797          * *exactly* the same as the argument to init_rwsem() --- in
6798          * this case, in init_once() --- or lockdep gets unhappy
6799          * because the name of the lock is set using the
6800          * stringification of the argument to init_rwsem().
6801          */
6802         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6803         lockdep_set_subclass(&ei->i_data_sem, subclass);
6804 }
6805
6806 /*
6807  * Standard function to be called on quota_on
6808  */
6809 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6810                          const struct path *path)
6811 {
6812         int err;
6813
6814         if (!test_opt(sb, QUOTA))
6815                 return -EINVAL;
6816
6817         /* Quotafile not on the same filesystem? */
6818         if (path->dentry->d_sb != sb)
6819                 return -EXDEV;
6820
6821         /* Quota already enabled for this file? */
6822         if (IS_NOQUOTA(d_inode(path->dentry)))
6823                 return -EBUSY;
6824
6825         /* Journaling quota? */
6826         if (EXT4_SB(sb)->s_qf_names[type]) {
6827                 /* Quotafile not in fs root? */
6828                 if (path->dentry->d_parent != sb->s_root)
6829                         ext4_msg(sb, KERN_WARNING,
6830                                 "Quota file not on filesystem root. "
6831                                 "Journaled quota will not work");
6832                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6833         } else {
6834                 /*
6835                  * Clear the flag just in case mount options changed since
6836                  * last time.
6837                  */
6838                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6839         }
6840
6841         /*
6842          * When we journal data on quota file, we have to flush journal to see
6843          * all updates to the file when we bypass pagecache...
6844          */
6845         if (EXT4_SB(sb)->s_journal &&
6846             ext4_should_journal_data(d_inode(path->dentry))) {
6847                 /*
6848                  * We don't need to lock updates but journal_flush() could
6849                  * otherwise be livelocked...
6850                  */
6851                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6852                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal, 0);
6853                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6854                 if (err)
6855                         return err;
6856         }
6857
6858         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6859         err = dquot_quota_on(sb, type, format_id, path);
6860         if (!err) {
6861                 struct inode *inode = d_inode(path->dentry);
6862                 handle_t *handle;
6863
6864                 /*
6865                  * Set inode flags to prevent userspace from messing with quota
6866                  * files. If this fails, we return success anyway since quotas
6867                  * are already enabled and this is not a hard failure.
6868                  */
6869                 inode_lock(inode);
6870                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6871                 if (IS_ERR(handle))
6872                         goto unlock_inode;
6873                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6874                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6875                                 S_NOATIME | S_IMMUTABLE);
6876                 err = ext4_mark_inode_dirty(handle, inode);
6877                 ext4_journal_stop(handle);
6878         unlock_inode:
6879                 inode_unlock(inode);
6880                 if (err)
6881                         dquot_quota_off(sb, type);
6882         }
6883         if (err)
6884                 lockdep_set_quota_inode(path->dentry->d_inode,
6885                                              I_DATA_SEM_NORMAL);
6886         return err;
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         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6906         if (IS_ERR(qf_inode)) {
6907                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6908                 return PTR_ERR(qf_inode);
6909         }
6910
6911         /* Don't account quota for quota files to avoid recursion */
6912         qf_inode->i_flags |= S_NOQUOTA;
6913         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6914         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6915         if (err)
6916                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6917         iput(qf_inode);
6918
6919         return err;
6920 }
6921
6922 /* Enable usage tracking for all quota types. */
6923 int ext4_enable_quotas(struct super_block *sb)
6924 {
6925         int type, err = 0;
6926         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6927                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6928                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6929                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6930         };
6931         bool quota_mopt[EXT4_MAXQUOTAS] = {
6932                 test_opt(sb, USRQUOTA),
6933                 test_opt(sb, GRPQUOTA),
6934                 test_opt(sb, PRJQUOTA),
6935         };
6936
6937         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6938         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6939                 if (qf_inums[type]) {
6940                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6941                                 DQUOT_USAGE_ENABLED |
6942                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6943                         if (err) {
6944                                 ext4_warning(sb,
6945                                         "Failed to enable quota tracking "
6946                                         "(type=%d, err=%d). Please run "
6947                                         "e2fsck to fix.", type, err);
6948                                 for (type--; type >= 0; type--) {
6949                                         struct inode *inode;
6950
6951                                         inode = sb_dqopt(sb)->files[type];
6952                                         if (inode)
6953                                                 inode = igrab(inode);
6954                                         dquot_quota_off(sb, type);
6955                                         if (inode) {
6956                                                 lockdep_set_quota_inode(inode,
6957                                                         I_DATA_SEM_NORMAL);
6958                                                 iput(inode);
6959                                         }
6960                                 }
6961
6962                                 return err;
6963                         }
6964                 }
6965         }
6966         return 0;
6967 }
6968
6969 static int ext4_quota_off(struct super_block *sb, int type)
6970 {
6971         struct inode *inode = sb_dqopt(sb)->files[type];
6972         handle_t *handle;
6973         int err;
6974
6975         /* Force all delayed allocation blocks to be allocated.
6976          * Caller already holds s_umount sem */
6977         if (test_opt(sb, DELALLOC))
6978                 sync_filesystem(sb);
6979
6980         if (!inode || !igrab(inode))
6981                 goto out;
6982
6983         err = dquot_quota_off(sb, type);
6984         if (err || ext4_has_feature_quota(sb))
6985                 goto out_put;
6986
6987         inode_lock(inode);
6988         /*
6989          * Update modification times of quota files when userspace can
6990          * start looking at them. If we fail, we return success anyway since
6991          * this is not a hard failure and quotas are already disabled.
6992          */
6993         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6994         if (IS_ERR(handle)) {
6995                 err = PTR_ERR(handle);
6996                 goto out_unlock;
6997         }
6998         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6999         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
7000         inode->i_mtime = inode->i_ctime = current_time(inode);
7001         err = ext4_mark_inode_dirty(handle, inode);
7002         ext4_journal_stop(handle);
7003 out_unlock:
7004         inode_unlock(inode);
7005 out_put:
7006         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
7007         iput(inode);
7008         return err;
7009 out:
7010         return dquot_quota_off(sb, type);
7011 }
7012
7013 /* Read data from quotafile - avoid pagecache and such because we cannot afford
7014  * acquiring the locks... As quota files are never truncated and quota code
7015  * itself serializes the operations (and no one else should touch the files)
7016  * we don't have to be afraid of races */
7017 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
7018                                size_t len, loff_t off)
7019 {
7020         struct inode *inode = sb_dqopt(sb)->files[type];
7021         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7022         int offset = off & (sb->s_blocksize - 1);
7023         int tocopy;
7024         size_t toread;
7025         struct buffer_head *bh;
7026         loff_t i_size = i_size_read(inode);
7027
7028         if (off > i_size)
7029                 return 0;
7030         if (off+len > i_size)
7031                 len = i_size-off;
7032         toread = len;
7033         while (toread > 0) {
7034                 tocopy = sb->s_blocksize - offset < toread ?
7035                                 sb->s_blocksize - offset : toread;
7036                 bh = ext4_bread(NULL, inode, blk, 0);
7037                 if (IS_ERR(bh))
7038                         return PTR_ERR(bh);
7039                 if (!bh)        /* A hole? */
7040                         memset(data, 0, tocopy);
7041                 else
7042                         memcpy(data, bh->b_data+offset, tocopy);
7043                 brelse(bh);
7044                 offset = 0;
7045                 toread -= tocopy;
7046                 data += tocopy;
7047                 blk++;
7048         }
7049         return len;
7050 }
7051
7052 /* Write to quotafile (we know the transaction is already started and has
7053  * enough credits) */
7054 static ssize_t ext4_quota_write(struct super_block *sb, int type,
7055                                 const char *data, size_t len, loff_t off)
7056 {
7057         struct inode *inode = sb_dqopt(sb)->files[type];
7058         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7059         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
7060         int retries = 0;
7061         struct buffer_head *bh;
7062         handle_t *handle = journal_current_handle();
7063
7064         if (!handle) {
7065                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7066                         " cancelled because transaction is not started",
7067                         (unsigned long long)off, (unsigned long long)len);
7068                 return -EIO;
7069         }
7070         /*
7071          * Since we account only one data block in transaction credits,
7072          * then it is impossible to cross a block boundary.
7073          */
7074         if (sb->s_blocksize - offset < len) {
7075                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7076                         " cancelled because not block aligned",
7077                         (unsigned long long)off, (unsigned long long)len);
7078                 return -EIO;
7079         }
7080
7081         do {
7082                 bh = ext4_bread(handle, inode, blk,
7083                                 EXT4_GET_BLOCKS_CREATE |
7084                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
7085         } while (PTR_ERR(bh) == -ENOSPC &&
7086                  ext4_should_retry_alloc(inode->i_sb, &retries));
7087         if (IS_ERR(bh))
7088                 return PTR_ERR(bh);
7089         if (!bh)
7090                 goto out;
7091         BUFFER_TRACE(bh, "get write access");
7092         err = ext4_journal_get_write_access(handle, sb, bh, EXT4_JTR_NONE);
7093         if (err) {
7094                 brelse(bh);
7095                 return err;
7096         }
7097         lock_buffer(bh);
7098         memcpy(bh->b_data+offset, data, len);
7099         flush_dcache_page(bh->b_page);
7100         unlock_buffer(bh);
7101         err = ext4_handle_dirty_metadata(handle, NULL, bh);
7102         brelse(bh);
7103 out:
7104         if (inode->i_size < off + len) {
7105                 i_size_write(inode, off + len);
7106                 EXT4_I(inode)->i_disksize = inode->i_size;
7107                 err2 = ext4_mark_inode_dirty(handle, inode);
7108                 if (unlikely(err2 && !err))
7109                         err = err2;
7110         }
7111         return err ? err : len;
7112 }
7113 #endif
7114
7115 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
7116 static inline void register_as_ext2(void)
7117 {
7118         int err = register_filesystem(&ext2_fs_type);
7119         if (err)
7120                 printk(KERN_WARNING
7121                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
7122 }
7123
7124 static inline void unregister_as_ext2(void)
7125 {
7126         unregister_filesystem(&ext2_fs_type);
7127 }
7128
7129 static inline int ext2_feature_set_ok(struct super_block *sb)
7130 {
7131         if (ext4_has_unknown_ext2_incompat_features(sb))
7132                 return 0;
7133         if (sb_rdonly(sb))
7134                 return 1;
7135         if (ext4_has_unknown_ext2_ro_compat_features(sb))
7136                 return 0;
7137         return 1;
7138 }
7139 #else
7140 static inline void register_as_ext2(void) { }
7141 static inline void unregister_as_ext2(void) { }
7142 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
7143 #endif
7144
7145 static inline void register_as_ext3(void)
7146 {
7147         int err = register_filesystem(&ext3_fs_type);
7148         if (err)
7149                 printk(KERN_WARNING
7150                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
7151 }
7152
7153 static inline void unregister_as_ext3(void)
7154 {
7155         unregister_filesystem(&ext3_fs_type);
7156 }
7157
7158 static inline int ext3_feature_set_ok(struct super_block *sb)
7159 {
7160         if (ext4_has_unknown_ext3_incompat_features(sb))
7161                 return 0;
7162         if (!ext4_has_feature_journal(sb))
7163                 return 0;
7164         if (sb_rdonly(sb))
7165                 return 1;
7166         if (ext4_has_unknown_ext3_ro_compat_features(sb))
7167                 return 0;
7168         return 1;
7169 }
7170
7171 static struct file_system_type ext4_fs_type = {
7172         .owner                  = THIS_MODULE,
7173         .name                   = "ext4",
7174         .init_fs_context        = ext4_init_fs_context,
7175         .parameters             = ext4_param_specs,
7176         .kill_sb                = kill_block_super,
7177         .fs_flags               = FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
7178 };
7179 MODULE_ALIAS_FS("ext4");
7180
7181 /* Shared across all ext4 file systems */
7182 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
7183
7184 static int __init ext4_init_fs(void)
7185 {
7186         int i, err;
7187
7188         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
7189         ext4_li_info = NULL;
7190
7191         /* Build-time check for flags consistency */
7192         ext4_check_flag_values();
7193
7194         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
7195                 init_waitqueue_head(&ext4__ioend_wq[i]);
7196
7197         err = ext4_init_es();
7198         if (err)
7199                 return err;
7200
7201         err = ext4_init_pending();
7202         if (err)
7203                 goto out7;
7204
7205         err = ext4_init_post_read_processing();
7206         if (err)
7207                 goto out6;
7208
7209         err = ext4_init_pageio();
7210         if (err)
7211                 goto out5;
7212
7213         err = ext4_init_system_zone();
7214         if (err)
7215                 goto out4;
7216
7217         err = ext4_init_sysfs();
7218         if (err)
7219                 goto out3;
7220
7221         err = ext4_init_mballoc();
7222         if (err)
7223                 goto out2;
7224         err = init_inodecache();
7225         if (err)
7226                 goto out1;
7227
7228         err = ext4_fc_init_dentry_cache();
7229         if (err)
7230                 goto out05;
7231
7232         register_as_ext3();
7233         register_as_ext2();
7234         err = register_filesystem(&ext4_fs_type);
7235         if (err)
7236                 goto out;
7237
7238         return 0;
7239 out:
7240         unregister_as_ext2();
7241         unregister_as_ext3();
7242         ext4_fc_destroy_dentry_cache();
7243 out05:
7244         destroy_inodecache();
7245 out1:
7246         ext4_exit_mballoc();
7247 out2:
7248         ext4_exit_sysfs();
7249 out3:
7250         ext4_exit_system_zone();
7251 out4:
7252         ext4_exit_pageio();
7253 out5:
7254         ext4_exit_post_read_processing();
7255 out6:
7256         ext4_exit_pending();
7257 out7:
7258         ext4_exit_es();
7259
7260         return err;
7261 }
7262
7263 static void __exit ext4_exit_fs(void)
7264 {
7265         ext4_destroy_lazyinit_thread();
7266         unregister_as_ext2();
7267         unregister_as_ext3();
7268         unregister_filesystem(&ext4_fs_type);
7269         ext4_fc_destroy_dentry_cache();
7270         destroy_inodecache();
7271         ext4_exit_mballoc();
7272         ext4_exit_sysfs();
7273         ext4_exit_system_zone();
7274         ext4_exit_pageio();
7275         ext4_exit_post_read_processing();
7276         ext4_exit_es();
7277         ext4_exit_pending();
7278 }
7279
7280 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
7281 MODULE_DESCRIPTION("Fourth Extended Filesystem");
7282 MODULE_LICENSE("GPL");
7283 MODULE_SOFTDEP("pre: crc32c");
7284 module_init(ext4_init_fs)
7285 module_exit(ext4_exit_fs)