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/cleancache.h>
  43 #include <linux/uaccess.h>
  44 #include <linux/iversion.h>
  45 #include <linux/unicode.h>
  46 #include <linux/part_stat.h>
  47 #include <linux/kthread.h>
  48 #include <linux/freezer.h>
  49
  50 #include "ext4.h"
  51 #include "ext4_extents.h"       /* Needed for trace points definition */
  52 #include "ext4_jbd2.h"
  53 #include "xattr.h"
  54 #include "acl.h"
  55 #include "mballoc.h"
  56 #include "fsmap.h"
  57
  58 #define CREATE_TRACE_POINTS
  59 #include <trace/events/ext4.h>
  60
  61 static struct ext4_lazy_init *ext4_li_info;
  62 static struct mutex ext4_li_mtx;
  63 static struct ratelimit_state ext4_mount_msg_ratelimit;
  64
  65 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  66                              unsigned long journal_devnum);
  67 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  68 static int ext4_commit_super(struct super_block *sb, int sync);
  69 static int ext4_mark_recovery_complete(struct super_block *sb,
  70                                         struct ext4_super_block *es);
  71 static int ext4_clear_journal_err(struct super_block *sb,
  72                                   struct ext4_super_block *es);
  73 static int ext4_sync_fs(struct super_block *sb, int wait);
  74 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  75 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  76 static int ext4_unfreeze(struct super_block *sb);
  77 static int ext4_freeze(struct super_block *sb);
  78 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  79                        const char *dev_name, void *data);
  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 int ext4_feature_set_ok(struct super_block *sb, int readonly);
  83 static void ext4_destroy_lazyinit_thread(void);
  84 static void ext4_unregister_li_request(struct super_block *sb);
  85 static void ext4_clear_request_list(void);
  86 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  87                                             unsigned int journal_inum);
  88
  89 /*
  90  * Lock ordering
  91  *
  92  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
  93  * i_mmap_rwsem (inode->i_mmap_rwsem)!
  94  *
  95  * page fault path:
  96  * mmap_lock -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
  97  *   page lock -> i_data_sem (rw)
  98  *
  99  * buffered write path:
 100  * sb_start_write -> i_mutex -> mmap_lock
 101  * sb_start_write -> i_mutex -> transaction start -> page lock ->
 102  *   i_data_sem (rw)
 103  *
 104  * truncate:
 105  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> i_mmap_rwsem (w) -> page lock
 106  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> transaction start ->
 107  *   i_data_sem (rw)
 108  *
 109  * direct IO:
 110  * sb_start_write -> i_mutex -> mmap_lock
 111  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
 112  *
 113  * writepages:
 114  * transaction start -> page lock(s) -> i_data_sem (rw)
 115  */
 116
 117 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 118 static struct file_system_type ext2_fs_type = {
 119         .owner          = THIS_MODULE,
 120         .name           = "ext2",
 121         .mount          = ext4_mount,
 122         .kill_sb        = kill_block_super,
 123         .fs_flags       = FS_REQUIRES_DEV,
 124 };
 125 MODULE_ALIAS_FS("ext2");
 126 MODULE_ALIAS("ext2");
 127 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
 128 #else
 129 #define IS_EXT2_SB(sb) (0)
 130 #endif
 131
 132
 133 static struct file_system_type ext3_fs_type = {
 134         .owner          = THIS_MODULE,
 135         .name           = "ext3",
 136         .mount          = ext4_mount,
 137         .kill_sb        = kill_block_super,
 138         .fs_flags       = FS_REQUIRES_DEV,
 139 };
 140 MODULE_ALIAS_FS("ext3");
 141 MODULE_ALIAS("ext3");
 142 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 143
 144
 145 static inline void __ext4_read_bh(struct buffer_head *bh, int op_flags,
 146                                   bh_end_io_t *end_io)
 147 {
 148         /*
 149          * buffer's verified bit is no longer valid after reading from
 150          * disk again due to write out error, clear it to make sure we
 151          * recheck the buffer contents.
 152          */
 153         clear_buffer_verified(bh);
 154
 155         bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
 156         get_bh(bh);
 157         submit_bh(REQ_OP_READ, op_flags, bh);
 158 }
 159
 160 void ext4_read_bh_nowait(struct buffer_head *bh, int op_flags,
 161                          bh_end_io_t *end_io)
 162 {
 163         BUG_ON(!buffer_locked(bh));
 164
 165         if (ext4_buffer_uptodate(bh)) {
 166                 unlock_buffer(bh);
 167                 return;
 168         }
 169         __ext4_read_bh(bh, op_flags, end_io);
 170 }
 171
 172 int ext4_read_bh(struct buffer_head *bh, int op_flags, bh_end_io_t *end_io)
 173 {
 174         BUG_ON(!buffer_locked(bh));
 175
 176         if (ext4_buffer_uptodate(bh)) {
 177                 unlock_buffer(bh);
 178                 return 0;
 179         }
 180
 181         __ext4_read_bh(bh, op_flags, end_io);
 182
 183         wait_on_buffer(bh);
 184         if (buffer_uptodate(bh))
 185                 return 0;
 186         return -EIO;
 187 }
 188
 189 int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait)
 190 {
 191         if (trylock_buffer(bh)) {
 192                 if (wait)
 193                         return ext4_read_bh(bh, op_flags, NULL);
 194                 ext4_read_bh_nowait(bh, op_flags, NULL);
 195                 return 0;
 196         }
 197         if (wait) {
 198                 wait_on_buffer(bh);
 199                 if (buffer_uptodate(bh))
 200                         return 0;
 201                 return -EIO;
 202         }
 203         return 0;
 204 }
 205
 206 /*
 207  * This works like __bread_gfp() except it uses ERR_PTR for error
 208  * returns.  Currently with sb_bread it's impossible to distinguish
 209  * between ENOMEM and EIO situations (since both result in a NULL
 210  * return.
 211  */
 212 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
 213                                                sector_t block, int op_flags,
 214                                                gfp_t gfp)
 215 {
 216         struct buffer_head *bh;
 217         int ret;
 218
 219         bh = sb_getblk_gfp(sb, block, gfp);
 220         if (bh == NULL)
 221                 return ERR_PTR(-ENOMEM);
 222         if (ext4_buffer_uptodate(bh))
 223                 return bh;
 224
 225         ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
 226         if (ret) {
 227                 put_bh(bh);
 228                 return ERR_PTR(ret);
 229         }
 230         return bh;
 231 }
 232
 233 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
 234                                    int op_flags)
 235 {
 236         return __ext4_sb_bread_gfp(sb, block, op_flags, __GFP_MOVABLE);
 237 }
 238
 239 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
 240                                             sector_t block)
 241 {
 242         return __ext4_sb_bread_gfp(sb, block, 0, 0);
 243 }
 244
 245 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
 246 {
 247         struct buffer_head *bh = sb_getblk_gfp(sb, block, 0);
 248
 249         if (likely(bh)) {
 250                 ext4_read_bh_lock(bh, REQ_RAHEAD, false);
 251                 brelse(bh);
 252         }
 253 }
 254
 255 static int ext4_verify_csum_type(struct super_block *sb,
 256                                  struct ext4_super_block *es)
 257 {
 258         if (!ext4_has_feature_metadata_csum(sb))
 259                 return 1;
 260
 261         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 262 }
 263
 264 static __le32 ext4_superblock_csum(struct super_block *sb,
 265                                    struct ext4_super_block *es)
 266 {
 267         struct ext4_sb_info *sbi = EXT4_SB(sb);
 268         int offset = offsetof(struct ext4_super_block, s_checksum);
 269         __u32 csum;
 270
 271         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 272
 273         return cpu_to_le32(csum);
 274 }
 275
 276 static int ext4_superblock_csum_verify(struct super_block *sb,
 277                                        struct ext4_super_block *es)
 278 {
 279         if (!ext4_has_metadata_csum(sb))
 280                 return 1;
 281
 282         return es->s_checksum == ext4_superblock_csum(sb, es);
 283 }
 284
 285 void ext4_superblock_csum_set(struct super_block *sb)
 286 {
 287         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 288
 289         if (!ext4_has_metadata_csum(sb))
 290                 return;
 291
 292         es->s_checksum = ext4_superblock_csum(sb, es);
 293 }
 294
 295 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 296                                struct ext4_group_desc *bg)
 297 {
 298         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 299                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 300                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 301 }
 302
 303 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 304                                struct ext4_group_desc *bg)
 305 {
 306         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 307                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 308                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 309 }
 310
 311 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 312                               struct ext4_group_desc *bg)
 313 {
 314         return le32_to_cpu(bg->bg_inode_table_lo) |
 315                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 316                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 317 }
 318
 319 __u32 ext4_free_group_clusters(struct super_block *sb,
 320                                struct ext4_group_desc *bg)
 321 {
 322         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 323                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 324                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 325 }
 326
 327 __u32 ext4_free_inodes_count(struct super_block *sb,
 328                               struct ext4_group_desc *bg)
 329 {
 330         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 331                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 332                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 333 }
 334
 335 __u32 ext4_used_dirs_count(struct super_block *sb,
 336                               struct ext4_group_desc *bg)
 337 {
 338         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 339                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 340                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 341 }
 342
 343 __u32 ext4_itable_unused_count(struct super_block *sb,
 344                               struct ext4_group_desc *bg)
 345 {
 346         return le16_to_cpu(bg->bg_itable_unused_lo) |
 347                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 348                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 349 }
 350
 351 void ext4_block_bitmap_set(struct super_block *sb,
 352                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 353 {
 354         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 355         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 356                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 357 }
 358
 359 void ext4_inode_bitmap_set(struct super_block *sb,
 360                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 361 {
 362         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 363         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 364                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 365 }
 366
 367 void ext4_inode_table_set(struct super_block *sb,
 368                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 369 {
 370         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 371         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 372                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 373 }
 374
 375 void ext4_free_group_clusters_set(struct super_block *sb,
 376                                   struct ext4_group_desc *bg, __u32 count)
 377 {
 378         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 379         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 380                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 381 }
 382
 383 void ext4_free_inodes_set(struct super_block *sb,
 384                           struct ext4_group_desc *bg, __u32 count)
 385 {
 386         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 387         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 388                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 389 }
 390
 391 void ext4_used_dirs_set(struct super_block *sb,
 392                           struct ext4_group_desc *bg, __u32 count)
 393 {
 394         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 395         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 396                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 397 }
 398
 399 void ext4_itable_unused_set(struct super_block *sb,
 400                           struct ext4_group_desc *bg, __u32 count)
 401 {
 402         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 403         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 404                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 405 }
 406
 407 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi)
 408 {
 409         time64_t now = ktime_get_real_seconds();
 410
 411         now = clamp_val(now, 0, (1ull << 40) - 1);
 412
 413         *lo = cpu_to_le32(lower_32_bits(now));
 414         *hi = upper_32_bits(now);
 415 }
 416
 417 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 418 {
 419         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 420 }
 421 #define ext4_update_tstamp(es, tstamp) \
 422         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 423 #define ext4_get_tstamp(es, tstamp) \
 424         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 425
 426 /*
 427  * The del_gendisk() function uninitializes the disk-specific data
 428  * structures, including the bdi structure, without telling anyone
 429  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 430  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 431  * This is a kludge to prevent these oops until we can put in a proper
 432  * hook in del_gendisk() to inform the VFS and file system layers.
 433  */
 434 static int block_device_ejected(struct super_block *sb)
 435 {
 436         struct inode *bd_inode = sb->s_bdev->bd_inode;
 437         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 438
 439         return bdi->dev == NULL;
 440 }
 441
 442 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 443 {
 444         struct super_block              *sb = journal->j_private;
 445         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 446         int                             error = is_journal_aborted(journal);
 447         struct ext4_journal_cb_entry    *jce;
 448
 449         BUG_ON(txn->t_state == T_FINISHED);
 450
 451         ext4_process_freed_data(sb, txn->t_tid);
 452
 453         spin_lock(&sbi->s_md_lock);
 454         while (!list_empty(&txn->t_private_list)) {
 455                 jce = list_entry(txn->t_private_list.next,
 456                                  struct ext4_journal_cb_entry, jce_list);
 457                 list_del_init(&jce->jce_list);
 458                 spin_unlock(&sbi->s_md_lock);
 459                 jce->jce_func(sb, jce, error);
 460                 spin_lock(&sbi->s_md_lock);
 461         }
 462         spin_unlock(&sbi->s_md_lock);
 463 }
 464
 465 /*
 466  * This writepage callback for write_cache_pages()
 467  * takes care of a few cases after page cleaning.
 468  *
 469  * write_cache_pages() already checks for dirty pages
 470  * and calls clear_page_dirty_for_io(), which we want,
 471  * to write protect the pages.
 472  *
 473  * However, we may have to redirty a page (see below.)
 474  */
 475 static int ext4_journalled_writepage_callback(struct page *page,
 476                                               struct writeback_control *wbc,
 477                                               void *data)
 478 {
 479         transaction_t *transaction = (transaction_t *) data;
 480         struct buffer_head *bh, *head;
 481         struct journal_head *jh;
 482
 483         bh = head = page_buffers(page);
 484         do {
 485                 /*
 486                  * We have to redirty a page in these cases:
 487                  * 1) If buffer is dirty, it means the page was dirty because it
 488                  * contains a buffer that needs checkpointing. So the dirty bit
 489                  * needs to be preserved so that checkpointing writes the buffer
 490                  * properly.
 491                  * 2) If buffer is not part of the committing transaction
 492                  * (we may have just accidentally come across this buffer because
 493                  * inode range tracking is not exact) or if the currently running
 494                  * transaction already contains this buffer as well, dirty bit
 495                  * needs to be preserved so that the buffer gets writeprotected
 496                  * properly on running transaction's commit.
 497                  */
 498                 jh = bh2jh(bh);
 499                 if (buffer_dirty(bh) ||
 500                     (jh && (jh->b_transaction != transaction ||
 501                             jh->b_next_transaction))) {
 502                         redirty_page_for_writepage(wbc, page);
 503                         goto out;
 504                 }
 505         } while ((bh = bh->b_this_page) != head);
 506
 507 out:
 508         return AOP_WRITEPAGE_ACTIVATE;
 509 }
 510
 511 static int ext4_journalled_submit_inode_data_buffers(struct jbd2_inode *jinode)
 512 {
 513         struct address_space *mapping = jinode->i_vfs_inode->i_mapping;
 514         struct writeback_control wbc = {
 515                 .sync_mode =  WB_SYNC_ALL,
 516                 .nr_to_write = LONG_MAX,
 517                 .range_start = jinode->i_dirty_start,
 518                 .range_end = jinode->i_dirty_end,
 519         };
 520
 521         return write_cache_pages(mapping, &wbc,
 522                                  ext4_journalled_writepage_callback,
 523                                  jinode->i_transaction);
 524 }
 525
 526 static int ext4_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
 527 {
 528         int ret;
 529
 530         if (ext4_should_journal_data(jinode->i_vfs_inode))
 531                 ret = ext4_journalled_submit_inode_data_buffers(jinode);
 532         else
 533                 ret = jbd2_journal_submit_inode_data_buffers(jinode);
 534
 535         return ret;
 536 }
 537
 538 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
 539 {
 540         int ret = 0;
 541
 542         if (!ext4_should_journal_data(jinode->i_vfs_inode))
 543                 ret = jbd2_journal_finish_inode_data_buffers(jinode);
 544
 545         return ret;
 546 }
 547
 548 static bool system_going_down(void)
 549 {
 550         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 551                 || system_state == SYSTEM_RESTART;
 552 }
 553
 554 struct ext4_err_translation {
 555         int code;
 556         int errno;
 557 };
 558
 559 #define EXT4_ERR_TRANSLATE(err) { .code = EXT4_ERR_##err, .errno = err }
 560
 561 static struct ext4_err_translation err_translation[] = {
 562         EXT4_ERR_TRANSLATE(EIO),
 563         EXT4_ERR_TRANSLATE(ENOMEM),
 564         EXT4_ERR_TRANSLATE(EFSBADCRC),
 565         EXT4_ERR_TRANSLATE(EFSCORRUPTED),
 566         EXT4_ERR_TRANSLATE(ENOSPC),
 567         EXT4_ERR_TRANSLATE(ENOKEY),
 568         EXT4_ERR_TRANSLATE(EROFS),
 569         EXT4_ERR_TRANSLATE(EFBIG),
 570         EXT4_ERR_TRANSLATE(EEXIST),
 571         EXT4_ERR_TRANSLATE(ERANGE),
 572         EXT4_ERR_TRANSLATE(EOVERFLOW),
 573         EXT4_ERR_TRANSLATE(EBUSY),
 574         EXT4_ERR_TRANSLATE(ENOTDIR),
 575         EXT4_ERR_TRANSLATE(ENOTEMPTY),
 576         EXT4_ERR_TRANSLATE(ESHUTDOWN),
 577         EXT4_ERR_TRANSLATE(EFAULT),
 578 };
 579
 580 static int ext4_errno_to_code(int errno)
 581 {
 582         int i;
 583
 584         for (i = 0; i < ARRAY_SIZE(err_translation); i++)
 585                 if (err_translation[i].errno == errno)
 586                         return err_translation[i].code;
 587         return EXT4_ERR_UNKNOWN;
 588 }
 589
 590 static void __save_error_info(struct super_block *sb, int error,
 591                               __u32 ino, __u64 block,
 592                               const char *func, unsigned int line)
 593 {
 594         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 595
 596         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 597         if (bdev_read_only(sb->s_bdev))
 598                 return;
 599         /* We default to EFSCORRUPTED error... */
 600         if (error == 0)
 601                 error = EFSCORRUPTED;
 602         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 603         ext4_update_tstamp(es, s_last_error_time);
 604         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 605         es->s_last_error_line = cpu_to_le32(line);
 606         es->s_last_error_ino = cpu_to_le32(ino);
 607         es->s_last_error_block = cpu_to_le64(block);
 608         es->s_last_error_errcode = ext4_errno_to_code(error);
 609         if (!es->s_first_error_time) {
 610                 es->s_first_error_time = es->s_last_error_time;
 611                 es->s_first_error_time_hi = es->s_last_error_time_hi;
 612                 strncpy(es->s_first_error_func, func,
 613                         sizeof(es->s_first_error_func));
 614                 es->s_first_error_line = cpu_to_le32(line);
 615                 es->s_first_error_ino = es->s_last_error_ino;
 616                 es->s_first_error_block = es->s_last_error_block;
 617                 es->s_first_error_errcode = es->s_last_error_errcode;
 618         }
 619         /*
 620          * Start the daily error reporting function if it hasn't been
 621          * started already
 622          */
 623         if (!es->s_error_count)
 624                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 625         le32_add_cpu(&es->s_error_count, 1);
 626 }
 627
 628 static void save_error_info(struct super_block *sb, int error,
 629                             __u32 ino, __u64 block,
 630                             const char *func, unsigned int line)
 631 {
 632         __save_error_info(sb, error, ino, block, func, line);
 633         if (!bdev_read_only(sb->s_bdev))
 634                 ext4_commit_super(sb, 1);
 635 }
 636
 637 /* Deal with the reporting of failure conditions on a filesystem such as
 638  * inconsistencies detected or read IO failures.
 639  *
 640  * On ext2, we can store the error state of the filesystem in the
 641  * superblock.  That is not possible on ext4, because we may have other
 642  * write ordering constraints on the superblock which prevent us from
 643  * writing it out straight away; and given that the journal is about to
 644  * be aborted, we can't rely on the current, or future, transactions to
 645  * write out the superblock safely.
 646  *
 647  * We'll just use the jbd2_journal_abort() error code to record an error in
 648  * the journal instead.  On recovery, the journal will complain about
 649  * that error until we've noted it down and cleared it.
 650  *
 651  * If force_ro is set, we unconditionally force the filesystem into an
 652  * ABORT|READONLY state, unless the error response on the fs has been set to
 653  * panic in which case we take the easy way out and panic immediately. This is
 654  * used to deal with unrecoverable failures such as journal IO errors or ENOMEM
 655  * at a critical moment in log management.
 656  */
 657 static void ext4_handle_error(struct super_block *sb, bool force_ro)
 658 {
 659         journal_t *journal = EXT4_SB(sb)->s_journal;
 660
 661         if (test_opt(sb, WARN_ON_ERROR))
 662                 WARN_ON_ONCE(1);
 663
 664         if (sb_rdonly(sb) || (!force_ro && test_opt(sb, ERRORS_CONT)))
 665                 return;
 666
 667         ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
 668         if (journal)
 669                 jbd2_journal_abort(journal, -EIO);
 670         /*
 671          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 672          * could panic during 'reboot -f' as the underlying device got already
 673          * disabled.
 674          */
 675         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
 676                 panic("EXT4-fs (device %s): panic forced after error\n",
 677                         sb->s_id);
 678         }
 679         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 680         /*
 681          * Make sure updated value of ->s_mount_flags will be visible before
 682          * ->s_flags update
 683          */
 684         smp_wmb();
 685         sb->s_flags |= SB_RDONLY;
 686 }
 687
 688 #define ext4_error_ratelimit(sb)                                        \
 689                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 690                              "EXT4-fs error")
 691
 692 void __ext4_error(struct super_block *sb, const char *function,
 693                   unsigned int line, bool force_ro, int error, __u64 block,
 694                   const char *fmt, ...)
 695 {
 696         struct va_format vaf;
 697         va_list args;
 698
 699         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 700                 return;
 701
 702         trace_ext4_error(sb, function, line);
 703         if (ext4_error_ratelimit(sb)) {
 704                 va_start(args, fmt);
 705                 vaf.fmt = fmt;
 706                 vaf.va = &args;
 707                 printk(KERN_CRIT
 708                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 709                        sb->s_id, function, line, current->comm, &vaf);
 710                 va_end(args);
 711         }
 712         save_error_info(sb, error, 0, block, function, line);
 713         ext4_handle_error(sb, force_ro);
 714 }
 715
 716 void __ext4_error_inode(struct inode *inode, const char *function,
 717                         unsigned int line, ext4_fsblk_t block, int error,
 718                         const char *fmt, ...)
 719 {
 720         va_list args;
 721         struct va_format vaf;
 722
 723         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 724                 return;
 725
 726         trace_ext4_error(inode->i_sb, function, line);
 727         if (ext4_error_ratelimit(inode->i_sb)) {
 728                 va_start(args, fmt);
 729                 vaf.fmt = fmt;
 730                 vaf.va = &args;
 731                 if (block)
 732                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 733                                "inode #%lu: block %llu: comm %s: %pV\n",
 734                                inode->i_sb->s_id, function, line, inode->i_ino,
 735                                block, current->comm, &vaf);
 736                 else
 737                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 738                                "inode #%lu: comm %s: %pV\n",
 739                                inode->i_sb->s_id, function, line, inode->i_ino,
 740                                current->comm, &vaf);
 741                 va_end(args);
 742         }
 743         save_error_info(inode->i_sb, error, inode->i_ino, block,
 744                         function, line);
 745         ext4_handle_error(inode->i_sb, false);
 746 }
 747
 748 void __ext4_error_file(struct file *file, const char *function,
 749                        unsigned int line, ext4_fsblk_t block,
 750                        const char *fmt, ...)
 751 {
 752         va_list args;
 753         struct va_format vaf;
 754         struct inode *inode = file_inode(file);
 755         char pathname[80], *path;
 756
 757         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 758                 return;
 759
 760         trace_ext4_error(inode->i_sb, function, line);
 761         if (ext4_error_ratelimit(inode->i_sb)) {
 762                 path = file_path(file, pathname, sizeof(pathname));
 763                 if (IS_ERR(path))
 764                         path = "(unknown)";
 765                 va_start(args, fmt);
 766                 vaf.fmt = fmt;
 767                 vaf.va = &args;
 768                 if (block)
 769                         printk(KERN_CRIT
 770                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 771                                "block %llu: comm %s: path %s: %pV\n",
 772                                inode->i_sb->s_id, function, line, inode->i_ino,
 773                                block, current->comm, path, &vaf);
 774                 else
 775                         printk(KERN_CRIT
 776                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 777                                "comm %s: path %s: %pV\n",
 778                                inode->i_sb->s_id, function, line, inode->i_ino,
 779                                current->comm, path, &vaf);
 780                 va_end(args);
 781         }
 782         save_error_info(inode->i_sb, EFSCORRUPTED, inode->i_ino, block,
 783                         function, line);
 784         ext4_handle_error(inode->i_sb, false);
 785 }
 786
 787 const char *ext4_decode_error(struct super_block *sb, int errno,
 788                               char nbuf[16])
 789 {
 790         char *errstr = NULL;
 791
 792         switch (errno) {
 793         case -EFSCORRUPTED:
 794                 errstr = "Corrupt filesystem";
 795                 break;
 796         case -EFSBADCRC:
 797                 errstr = "Filesystem failed CRC";
 798                 break;
 799         case -EIO:
 800                 errstr = "IO failure";
 801                 break;
 802         case -ENOMEM:
 803                 errstr = "Out of memory";
 804                 break;
 805         case -EROFS:
 806                 if (!sb || (EXT4_SB(sb)->s_journal &&
 807                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 808                         errstr = "Journal has aborted";
 809                 else
 810                         errstr = "Readonly filesystem";
 811                 break;
 812         default:
 813                 /* If the caller passed in an extra buffer for unknown
 814                  * errors, textualise them now.  Else we just return
 815                  * NULL. */
 816                 if (nbuf) {
 817                         /* Check for truncated error codes... */
 818                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 819                                 errstr = nbuf;
 820                 }
 821                 break;
 822         }
 823
 824         return errstr;
 825 }
 826
 827 /* __ext4_std_error decodes expected errors from journaling functions
 828  * automatically and invokes the appropriate error response.  */
 829
 830 void __ext4_std_error(struct super_block *sb, const char *function,
 831                       unsigned int line, int errno)
 832 {
 833         char nbuf[16];
 834         const char *errstr;
 835
 836         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 837                 return;
 838
 839         /* Special case: if the error is EROFS, and we're not already
 840          * inside a transaction, then there's really no point in logging
 841          * an error. */
 842         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 843                 return;
 844
 845         if (ext4_error_ratelimit(sb)) {
 846                 errstr = ext4_decode_error(sb, errno, nbuf);
 847                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 848                        sb->s_id, function, line, errstr);
 849         }
 850
 851         save_error_info(sb, -errno, 0, 0, function, line);
 852         ext4_handle_error(sb, false);
 853 }
 854
 855 void __ext4_msg(struct super_block *sb,
 856                 const char *prefix, const char *fmt, ...)
 857 {
 858         struct va_format vaf;
 859         va_list args;
 860
 861         atomic_inc(&EXT4_SB(sb)->s_msg_count);
 862         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 863                 return;
 864
 865         va_start(args, fmt);
 866         vaf.fmt = fmt;
 867         vaf.va = &args;
 868         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 869         va_end(args);
 870 }
 871
 872 static int ext4_warning_ratelimit(struct super_block *sb)
 873 {
 874         atomic_inc(&EXT4_SB(sb)->s_warning_count);
 875         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
 876                             "EXT4-fs warning");
 877 }
 878
 879 void __ext4_warning(struct super_block *sb, const char *function,
 880                     unsigned int line, const char *fmt, ...)
 881 {
 882         struct va_format vaf;
 883         va_list args;
 884
 885         if (!ext4_warning_ratelimit(sb))
 886                 return;
 887
 888         va_start(args, fmt);
 889         vaf.fmt = fmt;
 890         vaf.va = &args;
 891         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 892                sb->s_id, function, line, &vaf);
 893         va_end(args);
 894 }
 895
 896 void __ext4_warning_inode(const struct inode *inode, const char *function,
 897                           unsigned int line, const char *fmt, ...)
 898 {
 899         struct va_format vaf;
 900         va_list args;
 901
 902         if (!ext4_warning_ratelimit(inode->i_sb))
 903                 return;
 904
 905         va_start(args, fmt);
 906         vaf.fmt = fmt;
 907         vaf.va = &args;
 908         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 909                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 910                function, line, inode->i_ino, current->comm, &vaf);
 911         va_end(args);
 912 }
 913
 914 void __ext4_grp_locked_error(const char *function, unsigned int line,
 915                              struct super_block *sb, ext4_group_t grp,
 916                              unsigned long ino, ext4_fsblk_t block,
 917                              const char *fmt, ...)
 918 __releases(bitlock)
 919 __acquires(bitlock)
 920 {
 921         struct va_format vaf;
 922         va_list args;
 923
 924         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 925                 return;
 926
 927         trace_ext4_error(sb, function, line);
 928         __save_error_info(sb, EFSCORRUPTED, ino, block, function, line);
 929
 930         if (ext4_error_ratelimit(sb)) {
 931                 va_start(args, fmt);
 932                 vaf.fmt = fmt;
 933                 vaf.va = &args;
 934                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 935                        sb->s_id, function, line, grp);
 936                 if (ino)
 937                         printk(KERN_CONT "inode %lu: ", ino);
 938                 if (block)
 939                         printk(KERN_CONT "block %llu:",
 940                                (unsigned long long) block);
 941                 printk(KERN_CONT "%pV\n", &vaf);
 942                 va_end(args);
 943         }
 944
 945         if (test_opt(sb, WARN_ON_ERROR))
 946                 WARN_ON_ONCE(1);
 947
 948         if (test_opt(sb, ERRORS_CONT)) {
 949                 ext4_commit_super(sb, 0);
 950                 return;
 951         }
 952
 953         ext4_unlock_group(sb, grp);
 954         ext4_commit_super(sb, 1);
 955         ext4_handle_error(sb, false);
 956         /*
 957          * We only get here in the ERRORS_RO case; relocking the group
 958          * may be dangerous, but nothing bad will happen since the
 959          * filesystem will have already been marked read/only and the
 960          * journal has been aborted.  We return 1 as a hint to callers
 961          * who might what to use the return value from
 962          * ext4_grp_locked_error() to distinguish between the
 963          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 964          * aggressively from the ext4 function in question, with a
 965          * more appropriate error code.
 966          */
 967         ext4_lock_group(sb, grp);
 968         return;
 969 }
 970
 971 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
 972                                      ext4_group_t group,
 973                                      unsigned int flags)
 974 {
 975         struct ext4_sb_info *sbi = EXT4_SB(sb);
 976         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
 977         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
 978         int ret;
 979
 980         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
 981                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
 982                                             &grp->bb_state);
 983                 if (!ret)
 984                         percpu_counter_sub(&sbi->s_freeclusters_counter,
 985                                            grp->bb_free);
 986         }
 987
 988         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
 989                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
 990                                             &grp->bb_state);
 991                 if (!ret && gdp) {
 992                         int count;
 993
 994                         count = ext4_free_inodes_count(sb, gdp);
 995                         percpu_counter_sub(&sbi->s_freeinodes_counter,
 996                                            count);
 997                 }
 998         }
 999 }
1000
1001 void ext4_update_dynamic_rev(struct super_block *sb)
1002 {
1003         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1004
1005         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1006                 return;
1007
1008         ext4_warning(sb,
1009                      "updating to rev %d because of new feature flag, "
1010                      "running e2fsck is recommended",
1011                      EXT4_DYNAMIC_REV);
1012
1013         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1014         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1015         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1016         /* leave es->s_feature_*compat flags alone */
1017         /* es->s_uuid will be set by e2fsck if empty */
1018
1019         /*
1020          * The rest of the superblock fields should be zero, and if not it
1021          * means they are likely already in use, so leave them alone.  We
1022          * can leave it up to e2fsck to clean up any inconsistencies there.
1023          */
1024 }
1025
1026 /*
1027  * Open the external journal device
1028  */
1029 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
1030 {
1031         struct block_device *bdev;
1032
1033         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
1034         if (IS_ERR(bdev))
1035                 goto fail;
1036         return bdev;
1037
1038 fail:
1039         ext4_msg(sb, KERN_ERR,
1040                  "failed to open journal device unknown-block(%u,%u) %ld",
1041                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
1042         return NULL;
1043 }
1044
1045 /*
1046  * Release the journal device
1047  */
1048 static void ext4_blkdev_put(struct block_device *bdev)
1049 {
1050         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1051 }
1052
1053 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
1054 {
1055         struct block_device *bdev;
1056         bdev = sbi->s_journal_bdev;
1057         if (bdev) {
1058                 ext4_blkdev_put(bdev);
1059                 sbi->s_journal_bdev = NULL;
1060         }
1061 }
1062
1063 static inline struct inode *orphan_list_entry(struct list_head *l)
1064 {
1065         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1066 }
1067
1068 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1069 {
1070         struct list_head *l;
1071
1072         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1073                  le32_to_cpu(sbi->s_es->s_last_orphan));
1074
1075         printk(KERN_ERR "sb_info orphan list:\n");
1076         list_for_each(l, &sbi->s_orphan) {
1077                 struct inode *inode = orphan_list_entry(l);
1078                 printk(KERN_ERR "  "
1079                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1080                        inode->i_sb->s_id, inode->i_ino, inode,
1081                        inode->i_mode, inode->i_nlink,
1082                        NEXT_ORPHAN(inode));
1083         }
1084 }
1085
1086 #ifdef CONFIG_QUOTA
1087 static int ext4_quota_off(struct super_block *sb, int type);
1088
1089 static inline void ext4_quota_off_umount(struct super_block *sb)
1090 {
1091         int type;
1092
1093         /* Use our quota_off function to clear inode flags etc. */
1094         for (type = 0; type < EXT4_MAXQUOTAS; type++)
1095                 ext4_quota_off(sb, type);
1096 }
1097
1098 /*
1099  * This is a helper function which is used in the mount/remount
1100  * codepaths (which holds s_umount) to fetch the quota file name.
1101  */
1102 static inline char *get_qf_name(struct super_block *sb,
1103                                 struct ext4_sb_info *sbi,
1104                                 int type)
1105 {
1106         return rcu_dereference_protected(sbi->s_qf_names[type],
1107                                          lockdep_is_held(&sb->s_umount));
1108 }
1109 #else
1110 static inline void ext4_quota_off_umount(struct super_block *sb)
1111 {
1112 }
1113 #endif
1114
1115 static void ext4_put_super(struct super_block *sb)
1116 {
1117         struct ext4_sb_info *sbi = EXT4_SB(sb);
1118         struct ext4_super_block *es = sbi->s_es;
1119         struct buffer_head **group_desc;
1120         struct flex_groups **flex_groups;
1121         int aborted = 0;
1122         int i, err;
1123
1124         ext4_unregister_li_request(sb);
1125         ext4_quota_off_umount(sb);
1126
1127         destroy_workqueue(sbi->rsv_conversion_wq);
1128
1129         /*
1130          * Unregister sysfs before destroying jbd2 journal.
1131          * Since we could still access attr_journal_task attribute via sysfs
1132          * path which could have sbi->s_journal->j_task as NULL
1133          */
1134         ext4_unregister_sysfs(sb);
1135
1136         if (sbi->s_journal) {
1137                 aborted = is_journal_aborted(sbi->s_journal);
1138                 err = jbd2_journal_destroy(sbi->s_journal);
1139                 sbi->s_journal = NULL;
1140                 if ((err < 0) && !aborted) {
1141                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1142                 }
1143         }
1144
1145         ext4_es_unregister_shrinker(sbi);
1146         del_timer_sync(&sbi->s_err_report);
1147         ext4_release_system_zone(sb);
1148         ext4_mb_release(sb);
1149         ext4_ext_release(sb);
1150
1151         if (!sb_rdonly(sb) && !aborted) {
1152                 ext4_clear_feature_journal_needs_recovery(sb);
1153                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1154         }
1155         if (!sb_rdonly(sb))
1156                 ext4_commit_super(sb, 1);
1157
1158         rcu_read_lock();
1159         group_desc = rcu_dereference(sbi->s_group_desc);
1160         for (i = 0; i < sbi->s_gdb_count; i++)
1161                 brelse(group_desc[i]);
1162         kvfree(group_desc);
1163         flex_groups = rcu_dereference(sbi->s_flex_groups);
1164         if (flex_groups) {
1165                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1166                         kvfree(flex_groups[i]);
1167                 kvfree(flex_groups);
1168         }
1169         rcu_read_unlock();
1170         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1171         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1172         percpu_counter_destroy(&sbi->s_dirs_counter);
1173         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1174         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1175 #ifdef CONFIG_QUOTA
1176         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1177                 kfree(get_qf_name(sb, sbi, i));
1178 #endif
1179
1180         /* Debugging code just in case the in-memory inode orphan list
1181          * isn't empty.  The on-disk one can be non-empty if we've
1182          * detected an error and taken the fs readonly, but the
1183          * in-memory list had better be clean by this point. */
1184         if (!list_empty(&sbi->s_orphan))
1185                 dump_orphan_list(sb, sbi);
1186         ASSERT(list_empty(&sbi->s_orphan));
1187
1188         sync_blockdev(sb->s_bdev);
1189         invalidate_bdev(sb->s_bdev);
1190         if (sbi->s_journal_bdev && sbi->s_journal_bdev != sb->s_bdev) {
1191                 /*
1192                  * Invalidate the journal device's buffers.  We don't want them
1193                  * floating about in memory - the physical journal device may
1194                  * hotswapped, and it breaks the `ro-after' testing code.
1195                  */
1196                 sync_blockdev(sbi->s_journal_bdev);
1197                 invalidate_bdev(sbi->s_journal_bdev);
1198                 ext4_blkdev_remove(sbi);
1199         }
1200
1201         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1202         sbi->s_ea_inode_cache = NULL;
1203
1204         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1205         sbi->s_ea_block_cache = NULL;
1206
1207         if (sbi->s_mmp_tsk)
1208                 kthread_stop(sbi->s_mmp_tsk);
1209         brelse(sbi->s_sbh);
1210         sb->s_fs_info = NULL;
1211         /*
1212          * Now that we are completely done shutting down the
1213          * superblock, we need to actually destroy the kobject.
1214          */
1215         kobject_put(&sbi->s_kobj);
1216         wait_for_completion(&sbi->s_kobj_unregister);
1217         if (sbi->s_chksum_driver)
1218                 crypto_free_shash(sbi->s_chksum_driver);
1219         kfree(sbi->s_blockgroup_lock);
1220         fs_put_dax(sbi->s_daxdev);
1221         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1222 #ifdef CONFIG_UNICODE
1223         utf8_unload(sb->s_encoding);
1224 #endif
1225         kfree(sbi);
1226 }
1227
1228 static struct kmem_cache *ext4_inode_cachep;
1229
1230 /*
1231  * Called inside transaction, so use GFP_NOFS
1232  */
1233 static struct inode *ext4_alloc_inode(struct super_block *sb)
1234 {
1235         struct ext4_inode_info *ei;
1236
1237         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1238         if (!ei)
1239                 return NULL;
1240
1241         inode_set_iversion(&ei->vfs_inode, 1);
1242         spin_lock_init(&ei->i_raw_lock);
1243         INIT_LIST_HEAD(&ei->i_prealloc_list);
1244         atomic_set(&ei->i_prealloc_active, 0);
1245         spin_lock_init(&ei->i_prealloc_lock);
1246         ext4_es_init_tree(&ei->i_es_tree);
1247         rwlock_init(&ei->i_es_lock);
1248         INIT_LIST_HEAD(&ei->i_es_list);
1249         ei->i_es_all_nr = 0;
1250         ei->i_es_shk_nr = 0;
1251         ei->i_es_shrink_lblk = 0;
1252         ei->i_reserved_data_blocks = 0;
1253         spin_lock_init(&(ei->i_block_reservation_lock));
1254         ext4_init_pending_tree(&ei->i_pending_tree);
1255 #ifdef CONFIG_QUOTA
1256         ei->i_reserved_quota = 0;
1257         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1258 #endif
1259         ei->jinode = NULL;
1260         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1261         spin_lock_init(&ei->i_completed_io_lock);
1262         ei->i_sync_tid = 0;
1263         ei->i_datasync_tid = 0;
1264         atomic_set(&ei->i_unwritten, 0);
1265         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1266         ext4_fc_init_inode(&ei->vfs_inode);
1267         mutex_init(&ei->i_fc_lock);
1268         return &ei->vfs_inode;
1269 }
1270
1271 static int ext4_drop_inode(struct inode *inode)
1272 {
1273         int drop = generic_drop_inode(inode);
1274
1275         if (!drop)
1276                 drop = fscrypt_drop_inode(inode);
1277
1278         trace_ext4_drop_inode(inode, drop);
1279         return drop;
1280 }
1281
1282 static void ext4_free_in_core_inode(struct inode *inode)
1283 {
1284         fscrypt_free_inode(inode);
1285         if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1286                 pr_warn("%s: inode %ld still in fc list",
1287                         __func__, inode->i_ino);
1288         }
1289         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1290 }
1291
1292 static void ext4_destroy_inode(struct inode *inode)
1293 {
1294         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1295                 ext4_msg(inode->i_sb, KERN_ERR,
1296                          "Inode %lu (%p): orphan list check failed!",
1297                          inode->i_ino, EXT4_I(inode));
1298                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1299                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1300                                 true);
1301                 dump_stack();
1302         }
1303 }
1304
1305 static void init_once(void *foo)
1306 {
1307         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1308
1309         INIT_LIST_HEAD(&ei->i_orphan);
1310         init_rwsem(&ei->xattr_sem);
1311         init_rwsem(&ei->i_data_sem);
1312         init_rwsem(&ei->i_mmap_sem);
1313         inode_init_once(&ei->vfs_inode);
1314         ext4_fc_init_inode(&ei->vfs_inode);
1315 }
1316
1317 static int __init init_inodecache(void)
1318 {
1319         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1320                                 sizeof(struct ext4_inode_info), 0,
1321                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1322                                         SLAB_ACCOUNT),
1323                                 offsetof(struct ext4_inode_info, i_data),
1324                                 sizeof_field(struct ext4_inode_info, i_data),
1325                                 init_once);
1326         if (ext4_inode_cachep == NULL)
1327                 return -ENOMEM;
1328         return 0;
1329 }
1330
1331 static void destroy_inodecache(void)
1332 {
1333         /*
1334          * Make sure all delayed rcu free inodes are flushed before we
1335          * destroy cache.
1336          */
1337         rcu_barrier();
1338         kmem_cache_destroy(ext4_inode_cachep);
1339 }
1340
1341 void ext4_clear_inode(struct inode *inode)
1342 {
1343         ext4_fc_del(inode);
1344         invalidate_inode_buffers(inode);
1345         clear_inode(inode);
1346         ext4_discard_preallocations(inode, 0);
1347         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1348         dquot_drop(inode);
1349         if (EXT4_I(inode)->jinode) {
1350                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1351                                                EXT4_I(inode)->jinode);
1352                 jbd2_free_inode(EXT4_I(inode)->jinode);
1353                 EXT4_I(inode)->jinode = NULL;
1354         }
1355         fscrypt_put_encryption_info(inode);
1356         fsverity_cleanup_inode(inode);
1357 }
1358
1359 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1360                                         u64 ino, u32 generation)
1361 {
1362         struct inode *inode;
1363
1364         /*
1365          * Currently we don't know the generation for parent directory, so
1366          * a generation of 0 means "accept any"
1367          */
1368         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1369         if (IS_ERR(inode))
1370                 return ERR_CAST(inode);
1371         if (generation && inode->i_generation != generation) {
1372                 iput(inode);
1373                 return ERR_PTR(-ESTALE);
1374         }
1375
1376         return inode;
1377 }
1378
1379 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1380                                         int fh_len, int fh_type)
1381 {
1382         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1383                                     ext4_nfs_get_inode);
1384 }
1385
1386 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1387                                         int fh_len, int fh_type)
1388 {
1389         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1390                                     ext4_nfs_get_inode);
1391 }
1392
1393 static int ext4_nfs_commit_metadata(struct inode *inode)
1394 {
1395         struct writeback_control wbc = {
1396                 .sync_mode = WB_SYNC_ALL
1397         };
1398
1399         trace_ext4_nfs_commit_metadata(inode);
1400         return ext4_write_inode(inode, &wbc);
1401 }
1402
1403 /*
1404  * Try to release metadata pages (indirect blocks, directories) which are
1405  * mapped via the block device.  Since these pages could have journal heads
1406  * which would prevent try_to_free_buffers() from freeing them, we must use
1407  * jbd2 layer's try_to_free_buffers() function to release them.
1408  */
1409 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1410                                  gfp_t wait)
1411 {
1412         journal_t *journal = EXT4_SB(sb)->s_journal;
1413
1414         WARN_ON(PageChecked(page));
1415         if (!page_has_buffers(page))
1416                 return 0;
1417         if (journal)
1418                 return jbd2_journal_try_to_free_buffers(journal, page);
1419
1420         return try_to_free_buffers(page);
1421 }
1422
1423 #ifdef CONFIG_FS_ENCRYPTION
1424 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1425 {
1426         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1427                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1428 }
1429
1430 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1431                                                         void *fs_data)
1432 {
1433         handle_t *handle = fs_data;
1434         int res, res2, credits, retries = 0;
1435
1436         /*
1437          * Encrypting the root directory is not allowed because e2fsck expects
1438          * lost+found to exist and be unencrypted, and encrypting the root
1439          * directory would imply encrypting the lost+found directory as well as
1440          * the filename "lost+found" itself.
1441          */
1442         if (inode->i_ino == EXT4_ROOT_INO)
1443                 return -EPERM;
1444
1445         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1446                 return -EINVAL;
1447
1448         if (ext4_test_inode_flag(inode, EXT4_INODE_DAX))
1449                 return -EOPNOTSUPP;
1450
1451         res = ext4_convert_inline_data(inode);
1452         if (res)
1453                 return res;
1454
1455         /*
1456          * If a journal handle was specified, then the encryption context is
1457          * being set on a new inode via inheritance and is part of a larger
1458          * transaction to create the inode.  Otherwise the encryption context is
1459          * being set on an existing inode in its own transaction.  Only in the
1460          * latter case should the "retry on ENOSPC" logic be used.
1461          */
1462
1463         if (handle) {
1464                 res = ext4_xattr_set_handle(handle, inode,
1465                                             EXT4_XATTR_INDEX_ENCRYPTION,
1466                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1467                                             ctx, len, 0);
1468                 if (!res) {
1469                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1470                         ext4_clear_inode_state(inode,
1471                                         EXT4_STATE_MAY_INLINE_DATA);
1472                         /*
1473                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1474                          * S_DAX may be disabled
1475                          */
1476                         ext4_set_inode_flags(inode, false);
1477                 }
1478                 return res;
1479         }
1480
1481         res = dquot_initialize(inode);
1482         if (res)
1483                 return res;
1484 retry:
1485         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1486                                      &credits);
1487         if (res)
1488                 return res;
1489
1490         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1491         if (IS_ERR(handle))
1492                 return PTR_ERR(handle);
1493
1494         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1495                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1496                                     ctx, len, 0);
1497         if (!res) {
1498                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1499                 /*
1500                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1501                  * S_DAX may be disabled
1502                  */
1503                 ext4_set_inode_flags(inode, false);
1504                 res = ext4_mark_inode_dirty(handle, inode);
1505                 if (res)
1506                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1507         }
1508         res2 = ext4_journal_stop(handle);
1509
1510         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1511                 goto retry;
1512         if (!res)
1513                 res = res2;
1514         return res;
1515 }
1516
1517 static const union fscrypt_policy *ext4_get_dummy_policy(struct super_block *sb)
1518 {
1519         return EXT4_SB(sb)->s_dummy_enc_policy.policy;
1520 }
1521
1522 static bool ext4_has_stable_inodes(struct super_block *sb)
1523 {
1524         return ext4_has_feature_stable_inodes(sb);
1525 }
1526
1527 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1528                                        int *ino_bits_ret, int *lblk_bits_ret)
1529 {
1530         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1531         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1532 }
1533
1534 static const struct fscrypt_operations ext4_cryptops = {
1535         .key_prefix             = "ext4:",
1536         .get_context            = ext4_get_context,
1537         .set_context            = ext4_set_context,
1538         .get_dummy_policy       = ext4_get_dummy_policy,
1539         .empty_dir              = ext4_empty_dir,
1540         .max_namelen            = EXT4_NAME_LEN,
1541         .has_stable_inodes      = ext4_has_stable_inodes,
1542         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1543 };
1544 #endif
1545
1546 #ifdef CONFIG_QUOTA
1547 static const char * const quotatypes[] = INITQFNAMES;
1548 #define QTYPE2NAME(t) (quotatypes[t])
1549
1550 static int ext4_write_dquot(struct dquot *dquot);
1551 static int ext4_acquire_dquot(struct dquot *dquot);
1552 static int ext4_release_dquot(struct dquot *dquot);
1553 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1554 static int ext4_write_info(struct super_block *sb, int type);
1555 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1556                          const struct path *path);
1557 static int ext4_quota_on_mount(struct super_block *sb, int type);
1558 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1559                                size_t len, loff_t off);
1560 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1561                                 const char *data, size_t len, loff_t off);
1562 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1563                              unsigned int flags);
1564 static int ext4_enable_quotas(struct super_block *sb);
1565
1566 static struct dquot **ext4_get_dquots(struct inode *inode)
1567 {
1568         return EXT4_I(inode)->i_dquot;
1569 }
1570
1571 static const struct dquot_operations ext4_quota_operations = {
1572         .get_reserved_space     = ext4_get_reserved_space,
1573         .write_dquot            = ext4_write_dquot,
1574         .acquire_dquot          = ext4_acquire_dquot,
1575         .release_dquot          = ext4_release_dquot,
1576         .mark_dirty             = ext4_mark_dquot_dirty,
1577         .write_info             = ext4_write_info,
1578         .alloc_dquot            = dquot_alloc,
1579         .destroy_dquot          = dquot_destroy,
1580         .get_projid             = ext4_get_projid,
1581         .get_inode_usage        = ext4_get_inode_usage,
1582         .get_next_id            = dquot_get_next_id,
1583 };
1584
1585 static const struct quotactl_ops ext4_qctl_operations = {
1586         .quota_on       = ext4_quota_on,
1587         .quota_off      = ext4_quota_off,
1588         .quota_sync     = dquot_quota_sync,
1589         .get_state      = dquot_get_state,
1590         .set_info       = dquot_set_dqinfo,
1591         .get_dqblk      = dquot_get_dqblk,
1592         .set_dqblk      = dquot_set_dqblk,
1593         .get_nextdqblk  = dquot_get_next_dqblk,
1594 };
1595 #endif
1596
1597 static const struct super_operations ext4_sops = {
1598         .alloc_inode    = ext4_alloc_inode,
1599         .free_inode     = ext4_free_in_core_inode,
1600         .destroy_inode  = ext4_destroy_inode,
1601         .write_inode    = ext4_write_inode,
1602         .dirty_inode    = ext4_dirty_inode,
1603         .drop_inode     = ext4_drop_inode,
1604         .evict_inode    = ext4_evict_inode,
1605         .put_super      = ext4_put_super,
1606         .sync_fs        = ext4_sync_fs,
1607         .freeze_fs      = ext4_freeze,
1608         .unfreeze_fs    = ext4_unfreeze,
1609         .statfs         = ext4_statfs,
1610         .remount_fs     = ext4_remount,
1611         .show_options   = ext4_show_options,
1612 #ifdef CONFIG_QUOTA
1613         .quota_read     = ext4_quota_read,
1614         .quota_write    = ext4_quota_write,
1615         .get_dquots     = ext4_get_dquots,
1616 #endif
1617         .bdev_try_to_free_page = bdev_try_to_free_page,
1618 };
1619
1620 static const struct export_operations ext4_export_ops = {
1621         .fh_to_dentry = ext4_fh_to_dentry,
1622         .fh_to_parent = ext4_fh_to_parent,
1623         .get_parent = ext4_get_parent,
1624         .commit_metadata = ext4_nfs_commit_metadata,
1625 };
1626
1627 enum {
1628         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1629         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1630         Opt_nouid32, Opt_debug, Opt_removed,
1631         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1632         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1633         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1634         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1635         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1636         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1637         Opt_inlinecrypt,
1638         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1639         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1640         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1641         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
1642         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1643         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1644         Opt_nowarn_on_error, Opt_mblk_io_submit,
1645         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1646         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1647         Opt_inode_readahead_blks, Opt_journal_ioprio,
1648         Opt_dioread_nolock, Opt_dioread_lock,
1649         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1650         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1651         Opt_prefetch_block_bitmaps,
1652 #ifdef CONFIG_EXT4_DEBUG
1653         Opt_fc_debug_max_replay, Opt_fc_debug_force
1654 #endif
1655 };
1656
1657 static const match_table_t tokens = {
1658         {Opt_bsd_df, "bsddf"},
1659         {Opt_minix_df, "minixdf"},
1660         {Opt_grpid, "grpid"},
1661         {Opt_grpid, "bsdgroups"},
1662         {Opt_nogrpid, "nogrpid"},
1663         {Opt_nogrpid, "sysvgroups"},
1664         {Opt_resgid, "resgid=%u"},
1665         {Opt_resuid, "resuid=%u"},
1666         {Opt_sb, "sb=%u"},
1667         {Opt_err_cont, "errors=continue"},
1668         {Opt_err_panic, "errors=panic"},
1669         {Opt_err_ro, "errors=remount-ro"},
1670         {Opt_nouid32, "nouid32"},
1671         {Opt_debug, "debug"},
1672         {Opt_removed, "oldalloc"},
1673         {Opt_removed, "orlov"},
1674         {Opt_user_xattr, "user_xattr"},
1675         {Opt_nouser_xattr, "nouser_xattr"},
1676         {Opt_acl, "acl"},
1677         {Opt_noacl, "noacl"},
1678         {Opt_noload, "norecovery"},
1679         {Opt_noload, "noload"},
1680         {Opt_removed, "nobh"},
1681         {Opt_removed, "bh"},
1682         {Opt_commit, "commit=%u"},
1683         {Opt_min_batch_time, "min_batch_time=%u"},
1684         {Opt_max_batch_time, "max_batch_time=%u"},
1685         {Opt_journal_dev, "journal_dev=%u"},
1686         {Opt_journal_path, "journal_path=%s"},
1687         {Opt_journal_checksum, "journal_checksum"},
1688         {Opt_nojournal_checksum, "nojournal_checksum"},
1689         {Opt_journal_async_commit, "journal_async_commit"},
1690         {Opt_abort, "abort"},
1691         {Opt_data_journal, "data=journal"},
1692         {Opt_data_ordered, "data=ordered"},
1693         {Opt_data_writeback, "data=writeback"},
1694         {Opt_data_err_abort, "data_err=abort"},
1695         {Opt_data_err_ignore, "data_err=ignore"},
1696         {Opt_offusrjquota, "usrjquota="},
1697         {Opt_usrjquota, "usrjquota=%s"},
1698         {Opt_offgrpjquota, "grpjquota="},
1699         {Opt_grpjquota, "grpjquota=%s"},
1700         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1701         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1702         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1703         {Opt_grpquota, "grpquota"},
1704         {Opt_noquota, "noquota"},
1705         {Opt_quota, "quota"},
1706         {Opt_usrquota, "usrquota"},
1707         {Opt_prjquota, "prjquota"},
1708         {Opt_barrier, "barrier=%u"},
1709         {Opt_barrier, "barrier"},
1710         {Opt_nobarrier, "nobarrier"},
1711         {Opt_i_version, "i_version"},
1712         {Opt_dax, "dax"},
1713         {Opt_dax_always, "dax=always"},
1714         {Opt_dax_inode, "dax=inode"},
1715         {Opt_dax_never, "dax=never"},
1716         {Opt_stripe, "stripe=%u"},
1717         {Opt_delalloc, "delalloc"},
1718         {Opt_warn_on_error, "warn_on_error"},
1719         {Opt_nowarn_on_error, "nowarn_on_error"},
1720         {Opt_lazytime, "lazytime"},
1721         {Opt_nolazytime, "nolazytime"},
1722         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1723         {Opt_nodelalloc, "nodelalloc"},
1724         {Opt_removed, "mblk_io_submit"},
1725         {Opt_removed, "nomblk_io_submit"},
1726         {Opt_block_validity, "block_validity"},
1727         {Opt_noblock_validity, "noblock_validity"},
1728         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1729         {Opt_journal_ioprio, "journal_ioprio=%u"},
1730         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1731         {Opt_auto_da_alloc, "auto_da_alloc"},
1732         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1733         {Opt_dioread_nolock, "dioread_nolock"},
1734         {Opt_dioread_lock, "nodioread_nolock"},
1735         {Opt_dioread_lock, "dioread_lock"},
1736         {Opt_discard, "discard"},
1737         {Opt_nodiscard, "nodiscard"},
1738         {Opt_init_itable, "init_itable=%u"},
1739         {Opt_init_itable, "init_itable"},
1740         {Opt_noinit_itable, "noinit_itable"},
1741 #ifdef CONFIG_EXT4_DEBUG
1742         {Opt_fc_debug_force, "fc_debug_force"},
1743         {Opt_fc_debug_max_replay, "fc_debug_max_replay=%u"},
1744 #endif
1745         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1746         {Opt_test_dummy_encryption, "test_dummy_encryption=%s"},
1747         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1748         {Opt_inlinecrypt, "inlinecrypt"},
1749         {Opt_nombcache, "nombcache"},
1750         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1751         {Opt_prefetch_block_bitmaps, "prefetch_block_bitmaps"},
1752         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1753         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1754         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1755         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1756         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1757         {Opt_err, NULL},
1758 };
1759
1760 static ext4_fsblk_t get_sb_block(void **data)
1761 {
1762         ext4_fsblk_t    sb_block;
1763         char            *options = (char *) *data;
1764
1765         if (!options || strncmp(options, "sb=", 3) != 0)
1766                 return 1;       /* Default location */
1767
1768         options += 3;
1769         /* TODO: use simple_strtoll with >32bit ext4 */
1770         sb_block = simple_strtoul(options, &options, 0);
1771         if (*options && *options != ',') {
1772                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1773                        (char *) *data);
1774                 return 1;
1775         }
1776         if (*options == ',')
1777                 options++;
1778         *data = (void *) options;
1779
1780         return sb_block;
1781 }
1782
1783 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1784 static const char deprecated_msg[] =
1785         "Mount option \"%s\" will be removed by %s\n"
1786         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1787
1788 #ifdef CONFIG_QUOTA
1789 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1790 {
1791         struct ext4_sb_info *sbi = EXT4_SB(sb);
1792         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1793         int ret = -1;
1794
1795         if (sb_any_quota_loaded(sb) && !old_qname) {
1796                 ext4_msg(sb, KERN_ERR,
1797                         "Cannot change journaled "
1798                         "quota options when quota turned on");
1799                 return -1;
1800         }
1801         if (ext4_has_feature_quota(sb)) {
1802                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1803                          "ignored when QUOTA feature is enabled");
1804                 return 1;
1805         }
1806         qname = match_strdup(args);
1807         if (!qname) {
1808                 ext4_msg(sb, KERN_ERR,
1809                         "Not enough memory for storing quotafile name");
1810                 return -1;
1811         }
1812         if (old_qname) {
1813                 if (strcmp(old_qname, qname) == 0)
1814                         ret = 1;
1815                 else
1816                         ext4_msg(sb, KERN_ERR,
1817                                  "%s quota file already specified",
1818                                  QTYPE2NAME(qtype));
1819                 goto errout;
1820         }
1821         if (strchr(qname, '/')) {
1822                 ext4_msg(sb, KERN_ERR,
1823                         "quotafile must be on filesystem root");
1824                 goto errout;
1825         }
1826         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1827         set_opt(sb, QUOTA);
1828         return 1;
1829 errout:
1830         kfree(qname);
1831         return ret;
1832 }
1833
1834 static int clear_qf_name(struct super_block *sb, int qtype)
1835 {
1836
1837         struct ext4_sb_info *sbi = EXT4_SB(sb);
1838         char *old_qname = get_qf_name(sb, sbi, qtype);
1839
1840         if (sb_any_quota_loaded(sb) && old_qname) {
1841                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1842                         " when quota turned on");
1843                 return -1;
1844         }
1845         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1846         synchronize_rcu();
1847         kfree(old_qname);
1848         return 1;
1849 }
1850 #endif
1851
1852 #define MOPT_SET        0x0001
1853 #define MOPT_CLEAR      0x0002
1854 #define MOPT_NOSUPPORT  0x0004
1855 #define MOPT_EXPLICIT   0x0008
1856 #define MOPT_CLEAR_ERR  0x0010
1857 #define MOPT_GTE0       0x0020
1858 #ifdef CONFIG_QUOTA
1859 #define MOPT_Q          0
1860 #define MOPT_QFMT       0x0040
1861 #else
1862 #define MOPT_Q          MOPT_NOSUPPORT
1863 #define MOPT_QFMT       MOPT_NOSUPPORT
1864 #endif
1865 #define MOPT_DATAJ      0x0080
1866 #define MOPT_NO_EXT2    0x0100
1867 #define MOPT_NO_EXT3    0x0200
1868 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1869 #define MOPT_STRING     0x0400
1870 #define MOPT_SKIP       0x0800
1871 #define MOPT_2          0x1000
1872
1873 static const struct mount_opts {
1874         int     token;
1875         int     mount_opt;
1876         int     flags;
1877 } ext4_mount_opts[] = {
1878         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1879         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1880         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1881         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1882         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1883         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1884         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1885          MOPT_EXT4_ONLY | MOPT_SET},
1886         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1887          MOPT_EXT4_ONLY | MOPT_CLEAR},
1888         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1889         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1890         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1891          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1892         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1893          MOPT_EXT4_ONLY | MOPT_CLEAR},
1894         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1895         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1896         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1897          MOPT_EXT4_ONLY | MOPT_CLEAR},
1898         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1899          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1900         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1901                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1902          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1903         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1904         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1905         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1906         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1907         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1908          MOPT_NO_EXT2},
1909         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1910          MOPT_NO_EXT2},
1911         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1912         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1913         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1914         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1915         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1916         {Opt_commit, 0, MOPT_GTE0},
1917         {Opt_max_batch_time, 0, MOPT_GTE0},
1918         {Opt_min_batch_time, 0, MOPT_GTE0},
1919         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1920         {Opt_init_itable, 0, MOPT_GTE0},
1921         {Opt_dax, EXT4_MOUNT_DAX_ALWAYS, MOPT_SET | MOPT_SKIP},
1922         {Opt_dax_always, EXT4_MOUNT_DAX_ALWAYS,
1923                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1924         {Opt_dax_inode, EXT4_MOUNT2_DAX_INODE,
1925                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1926         {Opt_dax_never, EXT4_MOUNT2_DAX_NEVER,
1927                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1928         {Opt_stripe, 0, MOPT_GTE0},
1929         {Opt_resuid, 0, MOPT_GTE0},
1930         {Opt_resgid, 0, MOPT_GTE0},
1931         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1932         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1933         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1934         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1935         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1936         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1937          MOPT_NO_EXT2 | MOPT_DATAJ},
1938         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1939         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1940 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1941         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1942         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1943 #else
1944         {Opt_acl, 0, MOPT_NOSUPPORT},
1945         {Opt_noacl, 0, MOPT_NOSUPPORT},
1946 #endif
1947         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1948         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1949         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1950         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1951         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1952                                                         MOPT_SET | MOPT_Q},
1953         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1954                                                         MOPT_SET | MOPT_Q},
1955         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1956                                                         MOPT_SET | MOPT_Q},
1957         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1958                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1959                                                         MOPT_CLEAR | MOPT_Q},
1960         {Opt_usrjquota, 0, MOPT_Q | MOPT_STRING},
1961         {Opt_grpjquota, 0, MOPT_Q | MOPT_STRING},
1962         {Opt_offusrjquota, 0, MOPT_Q},
1963         {Opt_offgrpjquota, 0, MOPT_Q},
1964         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1965         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1966         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1967         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1968         {Opt_test_dummy_encryption, 0, MOPT_STRING},
1969         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1970         {Opt_prefetch_block_bitmaps, EXT4_MOUNT_PREFETCH_BLOCK_BITMAPS,
1971          MOPT_SET},
1972 #ifdef CONFIG_EXT4_DEBUG
1973         {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
1974          MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
1975         {Opt_fc_debug_max_replay, 0, MOPT_GTE0},
1976 #endif
1977         {Opt_err, 0, 0}
1978 };
1979
1980 #ifdef CONFIG_UNICODE
1981 static const struct ext4_sb_encodings {
1982         __u16 magic;
1983         char *name;
1984         char *version;
1985 } ext4_sb_encoding_map[] = {
1986         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
1987 };
1988
1989 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
1990                                  const struct ext4_sb_encodings **encoding,
1991                                  __u16 *flags)
1992 {
1993         __u16 magic = le16_to_cpu(es->s_encoding);
1994         int i;
1995
1996         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1997                 if (magic == ext4_sb_encoding_map[i].magic)
1998                         break;
1999
2000         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
2001                 return -EINVAL;
2002
2003         *encoding = &ext4_sb_encoding_map[i];
2004         *flags = le16_to_cpu(es->s_encoding_flags);
2005
2006         return 0;
2007 }
2008 #endif
2009
2010 static int ext4_set_test_dummy_encryption(struct super_block *sb,
2011                                           const char *opt,
2012                                           const substring_t *arg,
2013                                           bool is_remount)
2014 {
2015 #ifdef CONFIG_FS_ENCRYPTION
2016         struct ext4_sb_info *sbi = EXT4_SB(sb);
2017         int err;
2018
2019         /*
2020          * This mount option is just for testing, and it's not worthwhile to
2021          * implement the extra complexity (e.g. RCU protection) that would be
2022          * needed to allow it to be set or changed during remount.  We do allow
2023          * it to be specified during remount, but only if there is no change.
2024          */
2025         if (is_remount && !sbi->s_dummy_enc_policy.policy) {
2026                 ext4_msg(sb, KERN_WARNING,
2027                          "Can't set test_dummy_encryption on remount");
2028                 return -1;
2029         }
2030         err = fscrypt_set_test_dummy_encryption(sb, arg->from,
2031                                                 &sbi->s_dummy_enc_policy);
2032         if (err) {
2033                 if (err == -EEXIST)
2034                         ext4_msg(sb, KERN_WARNING,
2035                                  "Can't change test_dummy_encryption on remount");
2036                 else if (err == -EINVAL)
2037                         ext4_msg(sb, KERN_WARNING,
2038                                  "Value of option \"%s\" is unrecognized", opt);
2039                 else
2040                         ext4_msg(sb, KERN_WARNING,
2041                                  "Error processing option \"%s\" [%d]",
2042                                  opt, err);
2043                 return -1;
2044         }
2045         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2046 #else
2047         ext4_msg(sb, KERN_WARNING,
2048                  "Test dummy encryption mount option ignored");
2049 #endif
2050         return 1;
2051 }
2052
2053 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
2054                             substring_t *args, unsigned long *journal_devnum,
2055                             unsigned int *journal_ioprio, int is_remount)
2056 {
2057         struct ext4_sb_info *sbi = EXT4_SB(sb);
2058         const struct mount_opts *m;
2059         kuid_t uid;
2060         kgid_t gid;
2061         int arg = 0;
2062
2063 #ifdef CONFIG_QUOTA
2064         if (token == Opt_usrjquota)
2065                 return set_qf_name(sb, USRQUOTA, &args[0]);
2066         else if (token == Opt_grpjquota)
2067                 return set_qf_name(sb, GRPQUOTA, &args[0]);
2068         else if (token == Opt_offusrjquota)
2069                 return clear_qf_name(sb, USRQUOTA);
2070         else if (token == Opt_offgrpjquota)
2071                 return clear_qf_name(sb, GRPQUOTA);
2072 #endif
2073         switch (token) {
2074         case Opt_noacl:
2075         case Opt_nouser_xattr:
2076                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
2077                 break;
2078         case Opt_sb:
2079                 return 1;       /* handled by get_sb_block() */
2080         case Opt_removed:
2081                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
2082                 return 1;
2083         case Opt_abort:
2084                 ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
2085                 return 1;
2086         case Opt_i_version:
2087                 sb->s_flags |= SB_I_VERSION;
2088                 return 1;
2089         case Opt_lazytime:
2090                 sb->s_flags |= SB_LAZYTIME;
2091                 return 1;
2092         case Opt_nolazytime:
2093                 sb->s_flags &= ~SB_LAZYTIME;
2094                 return 1;
2095         case Opt_inlinecrypt:
2096 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2097                 sb->s_flags |= SB_INLINECRYPT;
2098 #else
2099                 ext4_msg(sb, KERN_ERR, "inline encryption not supported");
2100 #endif
2101                 return 1;
2102         }
2103
2104         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2105                 if (token == m->token)
2106                         break;
2107
2108         if (m->token == Opt_err) {
2109                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
2110                          "or missing value", opt);
2111                 return -1;
2112         }
2113
2114         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2115                 ext4_msg(sb, KERN_ERR,
2116                          "Mount option \"%s\" incompatible with ext2", opt);
2117                 return -1;
2118         }
2119         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2120                 ext4_msg(sb, KERN_ERR,
2121                          "Mount option \"%s\" incompatible with ext3", opt);
2122                 return -1;
2123         }
2124
2125         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
2126                 return -1;
2127         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
2128                 return -1;
2129         if (m->flags & MOPT_EXPLICIT) {
2130                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2131                         set_opt2(sb, EXPLICIT_DELALLOC);
2132                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2133                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
2134                 } else
2135                         return -1;
2136         }
2137         if (m->flags & MOPT_CLEAR_ERR)
2138                 clear_opt(sb, ERRORS_MASK);
2139         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
2140                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
2141                          "options when quota turned on");
2142                 return -1;
2143         }
2144
2145         if (m->flags & MOPT_NOSUPPORT) {
2146                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
2147         } else if (token == Opt_commit) {
2148                 if (arg == 0)
2149                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
2150                 else if (arg > INT_MAX / HZ) {
2151                         ext4_msg(sb, KERN_ERR,
2152                                  "Invalid commit interval %d, "
2153                                  "must be smaller than %d",
2154                                  arg, INT_MAX / HZ);
2155                         return -1;
2156                 }
2157                 sbi->s_commit_interval = HZ * arg;
2158         } else if (token == Opt_debug_want_extra_isize) {
2159                 if ((arg & 1) ||
2160                     (arg < 4) ||
2161                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
2162                         ext4_msg(sb, KERN_ERR,
2163                                  "Invalid want_extra_isize %d", arg);
2164                         return -1;
2165                 }
2166                 sbi->s_want_extra_isize = arg;
2167         } else if (token == Opt_max_batch_time) {
2168                 sbi->s_max_batch_time = arg;
2169         } else if (token == Opt_min_batch_time) {
2170                 sbi->s_min_batch_time = arg;
2171         } else if (token == Opt_inode_readahead_blks) {
2172                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
2173                         ext4_msg(sb, KERN_ERR,
2174                                  "EXT4-fs: inode_readahead_blks must be "
2175                                  "0 or a power of 2 smaller than 2^31");
2176                         return -1;
2177                 }
2178                 sbi->s_inode_readahead_blks = arg;
2179         } else if (token == Opt_init_itable) {
2180                 set_opt(sb, INIT_INODE_TABLE);
2181                 if (!args->from)
2182                         arg = EXT4_DEF_LI_WAIT_MULT;
2183                 sbi->s_li_wait_mult = arg;
2184         } else if (token == Opt_max_dir_size_kb) {
2185                 sbi->s_max_dir_size_kb = arg;
2186 #ifdef CONFIG_EXT4_DEBUG
2187         } else if (token == Opt_fc_debug_max_replay) {
2188                 sbi->s_fc_debug_max_replay = arg;
2189 #endif
2190         } else if (token == Opt_stripe) {
2191                 sbi->s_stripe = arg;
2192         } else if (token == Opt_resuid) {
2193                 uid = make_kuid(current_user_ns(), arg);
2194                 if (!uid_valid(uid)) {
2195                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
2196                         return -1;
2197                 }
2198                 sbi->s_resuid = uid;
2199         } else if (token == Opt_resgid) {
2200                 gid = make_kgid(current_user_ns(), arg);
2201                 if (!gid_valid(gid)) {
2202                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
2203                         return -1;
2204                 }
2205                 sbi->s_resgid = gid;
2206         } else if (token == Opt_journal_dev) {
2207                 if (is_remount) {
2208                         ext4_msg(sb, KERN_ERR,
2209                                  "Cannot specify journal on remount");
2210                         return -1;
2211                 }
2212                 *journal_devnum = arg;
2213         } else if (token == Opt_journal_path) {
2214                 char *journal_path;
2215                 struct inode *journal_inode;
2216                 struct path path;
2217                 int error;
2218
2219                 if (is_remount) {
2220                         ext4_msg(sb, KERN_ERR,
2221                                  "Cannot specify journal on remount");
2222                         return -1;
2223                 }
2224                 journal_path = match_strdup(&args[0]);
2225                 if (!journal_path) {
2226                         ext4_msg(sb, KERN_ERR, "error: could not dup "
2227                                 "journal device string");
2228                         return -1;
2229                 }
2230
2231                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2232                 if (error) {
2233                         ext4_msg(sb, KERN_ERR, "error: could not find "
2234                                 "journal device path: error %d", error);
2235                         kfree(journal_path);
2236                         return -1;
2237                 }
2238
2239                 journal_inode = d_inode(path.dentry);
2240                 if (!S_ISBLK(journal_inode->i_mode)) {
2241                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
2242                                 "is not a block device", journal_path);
2243                         path_put(&path);
2244                         kfree(journal_path);
2245                         return -1;
2246                 }
2247
2248                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
2249                 path_put(&path);
2250                 kfree(journal_path);
2251         } else if (token == Opt_journal_ioprio) {
2252                 if (arg > 7) {
2253                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2254                                  " (must be 0-7)");
2255                         return -1;
2256                 }
2257                 *journal_ioprio =
2258                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2259         } else if (token == Opt_test_dummy_encryption) {
2260                 return ext4_set_test_dummy_encryption(sb, opt, &args[0],
2261                                                       is_remount);
2262         } else if (m->flags & MOPT_DATAJ) {
2263                 if (is_remount) {
2264                         if (!sbi->s_journal)
2265                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2266                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2267                                 ext4_msg(sb, KERN_ERR,
2268                                          "Cannot change data mode on remount");
2269                                 return -1;
2270                         }
2271                 } else {
2272                         clear_opt(sb, DATA_FLAGS);
2273                         sbi->s_mount_opt |= m->mount_opt;
2274                 }
2275 #ifdef CONFIG_QUOTA
2276         } else if (m->flags & MOPT_QFMT) {
2277                 if (sb_any_quota_loaded(sb) &&
2278                     sbi->s_jquota_fmt != m->mount_opt) {
2279                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2280                                  "quota options when quota turned on");
2281                         return -1;
2282                 }
2283                 if (ext4_has_feature_quota(sb)) {
2284                         ext4_msg(sb, KERN_INFO,
2285                                  "Quota format mount options ignored "
2286                                  "when QUOTA feature is enabled");
2287                         return 1;
2288                 }
2289                 sbi->s_jquota_fmt = m->mount_opt;
2290 #endif
2291         } else if (token == Opt_dax || token == Opt_dax_always ||
2292                    token == Opt_dax_inode || token == Opt_dax_never) {
2293 #ifdef CONFIG_FS_DAX
2294                 switch (token) {
2295                 case Opt_dax:
2296                 case Opt_dax_always:
2297                         if (is_remount &&
2298                             (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2299                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2300                         fail_dax_change_remount:
2301                                 ext4_msg(sb, KERN_ERR, "can't change "
2302                                          "dax mount option while remounting");
2303                                 return -1;
2304                         }
2305                         if (is_remount &&
2306                             (test_opt(sb, DATA_FLAGS) ==
2307                              EXT4_MOUNT_JOURNAL_DATA)) {
2308                                     ext4_msg(sb, KERN_ERR, "can't mount with "
2309                                              "both data=journal and dax");
2310                                     return -1;
2311                         }
2312                         ext4_msg(sb, KERN_WARNING,
2313                                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2314                         sbi->s_mount_opt |= EXT4_MOUNT_DAX_ALWAYS;
2315                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2316                         break;
2317                 case Opt_dax_never:
2318                         if (is_remount &&
2319                             (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2320                              (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS)))
2321                                 goto fail_dax_change_remount;
2322                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2323                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2324                         break;
2325                 case Opt_dax_inode:
2326                         if (is_remount &&
2327                             ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2328                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2329                              !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE)))
2330                                 goto fail_dax_change_remount;
2331                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2332                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2333                         /* Strictly for printing options */
2334                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_INODE;
2335                         break;
2336                 }
2337 #else
2338                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2339                 sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2340                 sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2341                 return -1;
2342 #endif
2343         } else if (token == Opt_data_err_abort) {
2344                 sbi->s_mount_opt |= m->mount_opt;
2345         } else if (token == Opt_data_err_ignore) {
2346                 sbi->s_mount_opt &= ~m->mount_opt;
2347         } else {
2348                 if (!args->from)
2349                         arg = 1;
2350                 if (m->flags & MOPT_CLEAR)
2351                         arg = !arg;
2352                 else if (unlikely(!(m->flags & MOPT_SET))) {
2353                         ext4_msg(sb, KERN_WARNING,
2354                                  "buggy handling of option %s", opt);
2355                         WARN_ON(1);
2356                         return -1;
2357                 }
2358                 if (m->flags & MOPT_2) {
2359                         if (arg != 0)
2360                                 sbi->s_mount_opt2 |= m->mount_opt;
2361                         else
2362                                 sbi->s_mount_opt2 &= ~m->mount_opt;
2363                 } else {
2364                         if (arg != 0)
2365                                 sbi->s_mount_opt |= m->mount_opt;
2366                         else
2367                                 sbi->s_mount_opt &= ~m->mount_opt;
2368                 }
2369         }
2370         return 1;
2371 }
2372
2373 static int parse_options(char *options, struct super_block *sb,
2374                          unsigned long *journal_devnum,
2375                          unsigned int *journal_ioprio,
2376                          int is_remount)
2377 {
2378         struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2379         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2380         substring_t args[MAX_OPT_ARGS];
2381         int token;
2382
2383         if (!options)
2384                 return 1;
2385
2386         while ((p = strsep(&options, ",")) != NULL) {
2387                 if (!*p)
2388                         continue;
2389                 /*
2390                  * Initialize args struct so we know whether arg was
2391                  * found; some options take optional arguments.
2392                  */
2393                 args[0].to = args[0].from = NULL;
2394                 token = match_token(p, tokens, args);
2395                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2396                                      journal_ioprio, is_remount) < 0)
2397                         return 0;
2398         }
2399 #ifdef CONFIG_QUOTA
2400         /*
2401          * We do the test below only for project quotas. 'usrquota' and
2402          * 'grpquota' mount options are allowed even without quota feature
2403          * to support legacy quotas in quota files.
2404          */
2405         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2406                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2407                          "Cannot enable project quota enforcement.");
2408                 return 0;
2409         }
2410         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2411         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2412         if (usr_qf_name || grp_qf_name) {
2413                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2414                         clear_opt(sb, USRQUOTA);
2415
2416                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2417                         clear_opt(sb, GRPQUOTA);
2418
2419                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2420                         ext4_msg(sb, KERN_ERR, "old and new quota "
2421                                         "format mixing");
2422                         return 0;
2423                 }
2424
2425                 if (!sbi->s_jquota_fmt) {
2426                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2427                                         "not specified");
2428                         return 0;
2429                 }
2430         }
2431 #endif
2432         if (test_opt(sb, DIOREAD_NOLOCK)) {
2433                 int blocksize =
2434                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2435                 if (blocksize < PAGE_SIZE)
2436                         ext4_msg(sb, KERN_WARNING, "Warning: mounting with an "
2437                                  "experimental mount option 'dioread_nolock' "
2438                                  "for blocksize < PAGE_SIZE");
2439         }
2440         return 1;
2441 }
2442
2443 static inline void ext4_show_quota_options(struct seq_file *seq,
2444                                            struct super_block *sb)
2445 {
2446 #if defined(CONFIG_QUOTA)
2447         struct ext4_sb_info *sbi = EXT4_SB(sb);
2448         char *usr_qf_name, *grp_qf_name;
2449
2450         if (sbi->s_jquota_fmt) {
2451                 char *fmtname = "";
2452
2453                 switch (sbi->s_jquota_fmt) {
2454                 case QFMT_VFS_OLD:
2455                         fmtname = "vfsold";
2456                         break;
2457                 case QFMT_VFS_V0:
2458                         fmtname = "vfsv0";
2459                         break;
2460                 case QFMT_VFS_V1:
2461                         fmtname = "vfsv1";
2462                         break;
2463                 }
2464                 seq_printf(seq, ",jqfmt=%s", fmtname);
2465         }
2466
2467         rcu_read_lock();
2468         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2469         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2470         if (usr_qf_name)
2471                 seq_show_option(seq, "usrjquota", usr_qf_name);
2472         if (grp_qf_name)
2473                 seq_show_option(seq, "grpjquota", grp_qf_name);
2474         rcu_read_unlock();
2475 #endif
2476 }
2477
2478 static const char *token2str(int token)
2479 {
2480         const struct match_token *t;
2481
2482         for (t = tokens; t->token != Opt_err; t++)
2483                 if (t->token == token && !strchr(t->pattern, '='))
2484                         break;
2485         return t->pattern;
2486 }
2487
2488 /*
2489  * Show an option if
2490  *  - it's set to a non-default value OR
2491  *  - if the per-sb default is different from the global default
2492  */
2493 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2494                               int nodefs)
2495 {
2496         struct ext4_sb_info *sbi = EXT4_SB(sb);
2497         struct ext4_super_block *es = sbi->s_es;
2498         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2499         const struct mount_opts *m;
2500         char sep = nodefs ? '\n' : ',';
2501
2502 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2503 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2504
2505         if (sbi->s_sb_block != 1)
2506                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2507
2508         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2509                 int want_set = m->flags & MOPT_SET;
2510                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2511                     (m->flags & MOPT_CLEAR_ERR) || m->flags & MOPT_SKIP)
2512                         continue;
2513                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2514                         continue; /* skip if same as the default */
2515                 if ((want_set &&
2516                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2517                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2518                         continue; /* select Opt_noFoo vs Opt_Foo */
2519                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2520         }
2521
2522         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2523             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2524                 SEQ_OPTS_PRINT("resuid=%u",
2525                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2526         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2527             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2528                 SEQ_OPTS_PRINT("resgid=%u",
2529                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2530         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2531         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2532                 SEQ_OPTS_PUTS("errors=remount-ro");
2533         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2534                 SEQ_OPTS_PUTS("errors=continue");
2535         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2536                 SEQ_OPTS_PUTS("errors=panic");
2537         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2538                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2539         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2540                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2541         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2542                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2543         if (sb->s_flags & SB_I_VERSION)
2544                 SEQ_OPTS_PUTS("i_version");
2545         if (nodefs || sbi->s_stripe)
2546                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2547         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2548                         (sbi->s_mount_opt ^ def_mount_opt)) {
2549                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2550                         SEQ_OPTS_PUTS("data=journal");
2551                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2552                         SEQ_OPTS_PUTS("data=ordered");
2553                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2554                         SEQ_OPTS_PUTS("data=writeback");
2555         }
2556         if (nodefs ||
2557             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2558                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2559                                sbi->s_inode_readahead_blks);
2560
2561         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2562                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2563                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2564         if (nodefs || sbi->s_max_dir_size_kb)
2565                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2566         if (test_opt(sb, DATA_ERR_ABORT))
2567                 SEQ_OPTS_PUTS("data_err=abort");
2568
2569         fscrypt_show_test_dummy_encryption(seq, sep, sb);
2570
2571         if (sb->s_flags & SB_INLINECRYPT)
2572                 SEQ_OPTS_PUTS("inlinecrypt");
2573
2574         if (test_opt(sb, DAX_ALWAYS)) {
2575                 if (IS_EXT2_SB(sb))
2576                         SEQ_OPTS_PUTS("dax");
2577                 else
2578                         SEQ_OPTS_PUTS("dax=always");
2579         } else if (test_opt2(sb, DAX_NEVER)) {
2580                 SEQ_OPTS_PUTS("dax=never");
2581         } else if (test_opt2(sb, DAX_INODE)) {
2582                 SEQ_OPTS_PUTS("dax=inode");
2583         }
2584         ext4_show_quota_options(seq, sb);
2585         return 0;
2586 }
2587
2588 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2589 {
2590         return _ext4_show_options(seq, root->d_sb, 0);
2591 }
2592
2593 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2594 {
2595         struct super_block *sb = seq->private;
2596         int rc;
2597
2598         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2599         rc = _ext4_show_options(seq, sb, 1);
2600         seq_puts(seq, "\n");
2601         return rc;
2602 }
2603
2604 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2605                             int read_only)
2606 {
2607         struct ext4_sb_info *sbi = EXT4_SB(sb);
2608         int err = 0;
2609
2610         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2611                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2612                          "forcing read-only mode");
2613                 err = -EROFS;
2614                 goto done;
2615         }
2616         if (read_only)
2617                 goto done;
2618         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2619                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2620                          "running e2fsck is recommended");
2621         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2622                 ext4_msg(sb, KERN_WARNING,
2623                          "warning: mounting fs with errors, "
2624                          "running e2fsck is recommended");
2625         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2626                  le16_to_cpu(es->s_mnt_count) >=
2627                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2628                 ext4_msg(sb, KERN_WARNING,
2629                          "warning: maximal mount count reached, "
2630                          "running e2fsck is recommended");
2631         else if (le32_to_cpu(es->s_checkinterval) &&
2632                  (ext4_get_tstamp(es, s_lastcheck) +
2633                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2634                 ext4_msg(sb, KERN_WARNING,
2635                          "warning: checktime reached, "
2636                          "running e2fsck is recommended");
2637         if (!sbi->s_journal)
2638                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2639         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2640                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2641         le16_add_cpu(&es->s_mnt_count, 1);
2642         ext4_update_tstamp(es, s_mtime);
2643         if (sbi->s_journal)
2644                 ext4_set_feature_journal_needs_recovery(sb);
2645
2646         err = ext4_commit_super(sb, 1);
2647 done:
2648         if (test_opt(sb, DEBUG))
2649                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2650                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2651                         sb->s_blocksize,
2652                         sbi->s_groups_count,
2653                         EXT4_BLOCKS_PER_GROUP(sb),
2654                         EXT4_INODES_PER_GROUP(sb),
2655                         sbi->s_mount_opt, sbi->s_mount_opt2);
2656
2657         cleancache_init_fs(sb);
2658         return err;
2659 }
2660
2661 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2662 {
2663         struct ext4_sb_info *sbi = EXT4_SB(sb);
2664         struct flex_groups **old_groups, **new_groups;
2665         int size, i, j;
2666
2667         if (!sbi->s_log_groups_per_flex)
2668                 return 0;
2669
2670         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2671         if (size <= sbi->s_flex_groups_allocated)
2672                 return 0;
2673
2674         new_groups = kvzalloc(roundup_pow_of_two(size *
2675                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2676         if (!new_groups) {
2677                 ext4_msg(sb, KERN_ERR,
2678                          "not enough memory for %d flex group pointers", size);
2679                 return -ENOMEM;
2680         }
2681         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2682                 new_groups[i] = kvzalloc(roundup_pow_of_two(
2683                                          sizeof(struct flex_groups)),
2684                                          GFP_KERNEL);
2685                 if (!new_groups[i]) {
2686                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
2687                                 kvfree(new_groups[j]);
2688                         kvfree(new_groups);
2689                         ext4_msg(sb, KERN_ERR,
2690                                  "not enough memory for %d flex groups", size);
2691                         return -ENOMEM;
2692                 }
2693         }
2694         rcu_read_lock();
2695         old_groups = rcu_dereference(sbi->s_flex_groups);
2696         if (old_groups)
2697                 memcpy(new_groups, old_groups,
2698                        (sbi->s_flex_groups_allocated *
2699                         sizeof(struct flex_groups *)));
2700         rcu_read_unlock();
2701         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2702         sbi->s_flex_groups_allocated = size;
2703         if (old_groups)
2704                 ext4_kvfree_array_rcu(old_groups);
2705         return 0;
2706 }
2707
2708 static int ext4_fill_flex_info(struct super_block *sb)
2709 {
2710         struct ext4_sb_info *sbi = EXT4_SB(sb);
2711         struct ext4_group_desc *gdp = NULL;
2712         struct flex_groups *fg;
2713         ext4_group_t flex_group;
2714         int i, err;
2715
2716         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2717         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2718                 sbi->s_log_groups_per_flex = 0;
2719                 return 1;
2720         }
2721
2722         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2723         if (err)
2724                 goto failed;
2725
2726         for (i = 0; i < sbi->s_groups_count; i++) {
2727                 gdp = ext4_get_group_desc(sb, i, NULL);
2728
2729                 flex_group = ext4_flex_group(sbi, i);
2730                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2731                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2732                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2733                              &fg->free_clusters);
2734                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2735         }
2736
2737         return 1;
2738 failed:
2739         return 0;
2740 }
2741
2742 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2743                                    struct ext4_group_desc *gdp)
2744 {
2745         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2746         __u16 crc = 0;
2747         __le32 le_group = cpu_to_le32(block_group);
2748         struct ext4_sb_info *sbi = EXT4_SB(sb);
2749
2750         if (ext4_has_metadata_csum(sbi->s_sb)) {
2751                 /* Use new metadata_csum algorithm */
2752                 __u32 csum32;
2753                 __u16 dummy_csum = 0;
2754
2755                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2756                                      sizeof(le_group));
2757                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2758                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2759                                      sizeof(dummy_csum));
2760                 offset += sizeof(dummy_csum);
2761                 if (offset < sbi->s_desc_size)
2762                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2763                                              sbi->s_desc_size - offset);
2764
2765                 crc = csum32 & 0xFFFF;
2766                 goto out;
2767         }
2768
2769         /* old crc16 code */
2770         if (!ext4_has_feature_gdt_csum(sb))
2771                 return 0;
2772
2773         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2774         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2775         crc = crc16(crc, (__u8 *)gdp, offset);
2776         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2777         /* for checksum of struct ext4_group_desc do the rest...*/
2778         if (ext4_has_feature_64bit(sb) &&
2779             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2780                 crc = crc16(crc, (__u8 *)gdp + offset,
2781                             le16_to_cpu(sbi->s_es->s_desc_size) -
2782                                 offset);
2783
2784 out:
2785         return cpu_to_le16(crc);
2786 }
2787
2788 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2789                                 struct ext4_group_desc *gdp)
2790 {
2791         if (ext4_has_group_desc_csum(sb) &&
2792             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2793                 return 0;
2794
2795         return 1;
2796 }
2797
2798 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2799                               struct ext4_group_desc *gdp)
2800 {
2801         if (!ext4_has_group_desc_csum(sb))
2802                 return;
2803         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2804 }
2805
2806 /* Called at mount-time, super-block is locked */
2807 static int ext4_check_descriptors(struct super_block *sb,
2808                                   ext4_fsblk_t sb_block,
2809                                   ext4_group_t *first_not_zeroed)
2810 {
2811         struct ext4_sb_info *sbi = EXT4_SB(sb);
2812         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2813         ext4_fsblk_t last_block;
2814         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2815         ext4_fsblk_t block_bitmap;
2816         ext4_fsblk_t inode_bitmap;
2817         ext4_fsblk_t inode_table;
2818         int flexbg_flag = 0;
2819         ext4_group_t i, grp = sbi->s_groups_count;
2820
2821         if (ext4_has_feature_flex_bg(sb))
2822                 flexbg_flag = 1;
2823
2824         ext4_debug("Checking group descriptors");
2825
2826         for (i = 0; i < sbi->s_groups_count; i++) {
2827                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2828
2829                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2830                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2831                 else
2832                         last_block = first_block +
2833                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2834
2835                 if ((grp == sbi->s_groups_count) &&
2836                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2837                         grp = i;
2838
2839                 block_bitmap = ext4_block_bitmap(sb, gdp);
2840                 if (block_bitmap == sb_block) {
2841                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2842                                  "Block bitmap for group %u overlaps "
2843                                  "superblock", i);
2844                         if (!sb_rdonly(sb))
2845                                 return 0;
2846                 }
2847                 if (block_bitmap >= sb_block + 1 &&
2848                     block_bitmap <= last_bg_block) {
2849                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2850                                  "Block bitmap for group %u overlaps "
2851                                  "block group descriptors", i);
2852                         if (!sb_rdonly(sb))
2853                                 return 0;
2854                 }
2855                 if (block_bitmap < first_block || block_bitmap > last_block) {
2856                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2857                                "Block bitmap for group %u not in group "
2858                                "(block %llu)!", i, block_bitmap);
2859                         return 0;
2860                 }
2861                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2862                 if (inode_bitmap == sb_block) {
2863                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2864                                  "Inode bitmap for group %u overlaps "
2865                                  "superblock", i);
2866                         if (!sb_rdonly(sb))
2867                                 return 0;
2868                 }
2869                 if (inode_bitmap >= sb_block + 1 &&
2870                     inode_bitmap <= last_bg_block) {
2871                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2872                                  "Inode bitmap for group %u overlaps "
2873                                  "block group descriptors", i);
2874                         if (!sb_rdonly(sb))
2875                                 return 0;
2876                 }
2877                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2878                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2879                                "Inode bitmap for group %u not in group "
2880                                "(block %llu)!", i, inode_bitmap);
2881                         return 0;
2882                 }
2883                 inode_table = ext4_inode_table(sb, gdp);
2884                 if (inode_table == sb_block) {
2885                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2886                                  "Inode table for group %u overlaps "
2887                                  "superblock", i);
2888                         if (!sb_rdonly(sb))
2889                                 return 0;
2890                 }
2891                 if (inode_table >= sb_block + 1 &&
2892                     inode_table <= last_bg_block) {
2893                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2894                                  "Inode table for group %u overlaps "
2895                                  "block group descriptors", i);
2896                         if (!sb_rdonly(sb))
2897                                 return 0;
2898                 }
2899                 if (inode_table < first_block ||
2900                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2901                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2902                                "Inode table for group %u not in group "
2903                                "(block %llu)!", i, inode_table);
2904                         return 0;
2905                 }
2906                 ext4_lock_group(sb, i);
2907                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2908                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2909                                  "Checksum for group %u failed (%u!=%u)",
2910                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2911                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2912                         if (!sb_rdonly(sb)) {
2913                                 ext4_unlock_group(sb, i);
2914                                 return 0;
2915                         }
2916                 }
2917                 ext4_unlock_group(sb, i);
2918                 if (!flexbg_flag)
2919                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2920         }
2921         if (NULL != first_not_zeroed)
2922                 *first_not_zeroed = grp;
2923         return 1;
2924 }
2925
2926 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2927  * the superblock) which were deleted from all directories, but held open by
2928  * a process at the time of a crash.  We walk the list and try to delete these
2929  * inodes at recovery time (only with a read-write filesystem).
2930  *
2931  * In order to keep the orphan inode chain consistent during traversal (in
2932  * case of crash during recovery), we link each inode into the superblock
2933  * orphan list_head and handle it the same way as an inode deletion during
2934  * normal operation (which journals the operations for us).
2935  *
2936  * We only do an iget() and an iput() on each inode, which is very safe if we
2937  * accidentally point at an in-use or already deleted inode.  The worst that
2938  * can happen in this case is that we get a "bit already cleared" message from
2939  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2940  * e2fsck was run on this filesystem, and it must have already done the orphan
2941  * inode cleanup for us, so we can safely abort without any further action.
2942  */
2943 static void ext4_orphan_cleanup(struct super_block *sb,
2944                                 struct ext4_super_block *es)
2945 {
2946         unsigned int s_flags = sb->s_flags;
2947         int ret, nr_orphans = 0, nr_truncates = 0;
2948 #ifdef CONFIG_QUOTA
2949         int quota_update = 0;
2950         int i;
2951 #endif
2952         if (!es->s_last_orphan) {
2953                 jbd_debug(4, "no orphan inodes to clean up\n");
2954                 return;
2955         }
2956
2957         if (bdev_read_only(sb->s_bdev)) {
2958                 ext4_msg(sb, KERN_ERR, "write access "
2959                         "unavailable, skipping orphan cleanup");
2960                 return;
2961         }
2962
2963         /* Check if feature set would not allow a r/w mount */
2964         if (!ext4_feature_set_ok(sb, 0)) {
2965                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2966                          "unknown ROCOMPAT features");
2967                 return;
2968         }
2969
2970         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2971                 /* don't clear list on RO mount w/ errors */
2972                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2973                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2974                                   "clearing orphan list.\n");
2975                         es->s_last_orphan = 0;
2976                 }
2977                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2978                 return;
2979         }
2980
2981         if (s_flags & SB_RDONLY) {
2982                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2983                 sb->s_flags &= ~SB_RDONLY;
2984         }
2985 #ifdef CONFIG_QUOTA
2986         /* Needed for iput() to work correctly and not trash data */
2987         sb->s_flags |= SB_ACTIVE;
2988
2989         /*
2990          * Turn on quotas which were not enabled for read-only mounts if
2991          * filesystem has quota feature, so that they are updated correctly.
2992          */
2993         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2994                 int ret = ext4_enable_quotas(sb);
2995
2996                 if (!ret)
2997                         quota_update = 1;
2998                 else
2999                         ext4_msg(sb, KERN_ERR,
3000                                 "Cannot turn on quotas: error %d", ret);
3001         }
3002
3003         /* Turn on journaled quotas used for old sytle */
3004         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3005                 if (EXT4_SB(sb)->s_qf_names[i]) {
3006                         int ret = ext4_quota_on_mount(sb, i);
3007
3008                         if (!ret)
3009                                 quota_update = 1;
3010                         else
3011                                 ext4_msg(sb, KERN_ERR,
3012                                         "Cannot turn on journaled "
3013                                         "quota: type %d: error %d", i, ret);
3014                 }
3015         }
3016 #endif
3017
3018         while (es->s_last_orphan) {
3019                 struct inode *inode;
3020
3021                 /*
3022                  * We may have encountered an error during cleanup; if
3023                  * so, skip the rest.
3024                  */
3025                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
3026                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
3027                         es->s_last_orphan = 0;
3028                         break;
3029                 }
3030
3031                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
3032                 if (IS_ERR(inode)) {
3033                         es->s_last_orphan = 0;
3034                         break;
3035                 }
3036
3037                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
3038                 dquot_initialize(inode);
3039                 if (inode->i_nlink) {
3040                         if (test_opt(sb, DEBUG))
3041                                 ext4_msg(sb, KERN_DEBUG,
3042                                         "%s: truncating inode %lu to %lld bytes",
3043                                         __func__, inode->i_ino, inode->i_size);
3044                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
3045                                   inode->i_ino, inode->i_size);
3046                         inode_lock(inode);
3047                         truncate_inode_pages(inode->i_mapping, inode->i_size);
3048                         ret = ext4_truncate(inode);
3049                         if (ret)
3050                                 ext4_std_error(inode->i_sb, ret);
3051                         inode_unlock(inode);
3052                         nr_truncates++;
3053                 } else {
3054                         if (test_opt(sb, DEBUG))
3055                                 ext4_msg(sb, KERN_DEBUG,
3056                                         "%s: deleting unreferenced inode %lu",
3057                                         __func__, inode->i_ino);
3058                         jbd_debug(2, "deleting unreferenced inode %lu\n",
3059                                   inode->i_ino);
3060                         nr_orphans++;
3061                 }
3062                 iput(inode);  /* The delete magic happens here! */
3063         }
3064
3065 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
3066
3067         if (nr_orphans)
3068                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
3069                        PLURAL(nr_orphans));
3070         if (nr_truncates)
3071                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
3072                        PLURAL(nr_truncates));
3073 #ifdef CONFIG_QUOTA
3074         /* Turn off quotas if they were enabled for orphan cleanup */
3075         if (quota_update) {
3076                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3077                         if (sb_dqopt(sb)->files[i])
3078                                 dquot_quota_off(sb, i);
3079                 }
3080         }
3081 #endif
3082         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
3083 }
3084
3085 /*
3086  * Maximal extent format file size.
3087  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3088  * extent format containers, within a sector_t, and within i_blocks
3089  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3090  * so that won't be a limiting factor.
3091  *
3092  * However there is other limiting factor. We do store extents in the form
3093  * of starting block and length, hence the resulting length of the extent
3094  * covering maximum file size must fit into on-disk format containers as
3095  * well. Given that length is always by 1 unit bigger than max unit (because
3096  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3097  *
3098  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3099  */
3100 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3101 {
3102         loff_t res;
3103         loff_t upper_limit = MAX_LFS_FILESIZE;
3104
3105         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3106
3107         if (!has_huge_files) {
3108                 upper_limit = (1LL << 32) - 1;
3109
3110                 /* total blocks in file system block size */
3111                 upper_limit >>= (blkbits - 9);
3112                 upper_limit <<= blkbits;
3113         }
3114
3115         /*
3116          * 32-bit extent-start container, ee_block. We lower the maxbytes
3117          * by one fs block, so ee_len can cover the extent of maximum file
3118          * size
3119          */
3120         res = (1LL << 32) - 1;
3121         res <<= blkbits;
3122
3123         /* Sanity check against vm- & vfs- imposed limits */
3124         if (res > upper_limit)
3125                 res = upper_limit;
3126
3127         return res;
3128 }
3129
3130 /*
3131  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3132  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3133  * We need to be 1 filesystem block less than the 2^48 sector limit.
3134  */
3135 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3136 {
3137         loff_t res = EXT4_NDIR_BLOCKS;
3138         int meta_blocks;
3139         loff_t upper_limit;
3140         /* This is calculated to be the largest file size for a dense, block
3141          * mapped file such that the file's total number of 512-byte sectors,
3142          * including data and all indirect blocks, does not exceed (2^48 - 1).
3143          *
3144          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3145          * number of 512-byte sectors of the file.
3146          */
3147
3148         if (!has_huge_files) {
3149                 /*
3150                  * !has_huge_files or implies that the inode i_block field
3151                  * represents total file blocks in 2^32 512-byte sectors ==
3152                  * size of vfs inode i_blocks * 8
3153                  */
3154                 upper_limit = (1LL << 32) - 1;
3155
3156                 /* total blocks in file system block size */
3157                 upper_limit >>= (bits - 9);
3158
3159         } else {
3160                 /*
3161                  * We use 48 bit ext4_inode i_blocks
3162                  * With EXT4_HUGE_FILE_FL set the i_blocks
3163                  * represent total number of blocks in
3164                  * file system block size
3165                  */
3166                 upper_limit = (1LL << 48) - 1;
3167
3168         }
3169
3170         /* indirect blocks */
3171         meta_blocks = 1;
3172         /* double indirect blocks */
3173         meta_blocks += 1 + (1LL << (bits-2));
3174         /* tripple indirect blocks */
3175         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
3176
3177         upper_limit -= meta_blocks;
3178         upper_limit <<= bits;
3179
3180         res += 1LL << (bits-2);
3181         res += 1LL << (2*(bits-2));
3182         res += 1LL << (3*(bits-2));
3183         res <<= bits;
3184         if (res > upper_limit)
3185                 res = upper_limit;
3186
3187         if (res > MAX_LFS_FILESIZE)
3188                 res = MAX_LFS_FILESIZE;
3189
3190         return res;
3191 }
3192
3193 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3194                                    ext4_fsblk_t logical_sb_block, int nr)
3195 {
3196         struct ext4_sb_info *sbi = EXT4_SB(sb);
3197         ext4_group_t bg, first_meta_bg;
3198         int has_super = 0;
3199
3200         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3201
3202         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3203                 return logical_sb_block + nr + 1;
3204         bg = sbi->s_desc_per_block * nr;
3205         if (ext4_bg_has_super(sb, bg))
3206                 has_super = 1;
3207
3208         /*
3209          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3210          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3211          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3212          * compensate.
3213          */
3214         if (sb->s_blocksize == 1024 && nr == 0 &&
3215             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3216                 has_super++;
3217
3218         return (has_super + ext4_group_first_block_no(sb, bg));
3219 }
3220
3221 /**
3222  * ext4_get_stripe_size: Get the stripe size.
3223  * @sbi: In memory super block info
3224  *
3225  * If we have specified it via mount option, then
3226  * use the mount option value. If the value specified at mount time is
3227  * greater than the blocks per group use the super block value.
3228  * If the super block value is greater than blocks per group return 0.
3229  * Allocator needs it be less than blocks per group.
3230  *
3231  */
3232 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3233 {
3234         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3235         unsigned long stripe_width =
3236                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3237         int ret;
3238
3239         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3240                 ret = sbi->s_stripe;
3241         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3242                 ret = stripe_width;
3243         else if (stride && stride <= sbi->s_blocks_per_group)
3244                 ret = stride;
3245         else
3246                 ret = 0;
3247
3248         /*
3249          * If the stripe width is 1, this makes no sense and
3250          * we set it to 0 to turn off stripe handling code.
3251          */
3252         if (ret <= 1)
3253                 ret = 0;
3254
3255         return ret;
3256 }
3257
3258 /*
3259  * Check whether this filesystem can be mounted based on
3260  * the features present and the RDONLY/RDWR mount requested.
3261  * Returns 1 if this filesystem can be mounted as requested,
3262  * 0 if it cannot be.
3263  */
3264 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
3265 {
3266         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3267                 ext4_msg(sb, KERN_ERR,
3268                         "Couldn't mount because of "
3269                         "unsupported optional features (%x)",
3270                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3271                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3272                 return 0;
3273         }
3274
3275 #ifndef CONFIG_UNICODE
3276         if (ext4_has_feature_casefold(sb)) {
3277                 ext4_msg(sb, KERN_ERR,
3278                          "Filesystem with casefold feature cannot be "
3279                          "mounted without CONFIG_UNICODE");
3280                 return 0;
3281         }
3282 #endif
3283
3284         if (readonly)
3285                 return 1;
3286
3287         if (ext4_has_feature_readonly(sb)) {
3288                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3289                 sb->s_flags |= SB_RDONLY;
3290                 return 1;
3291         }
3292
3293         /* Check that feature set is OK for a read-write mount */
3294         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3295                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3296                          "unsupported optional features (%x)",
3297                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3298                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3299                 return 0;
3300         }
3301         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3302                 ext4_msg(sb, KERN_ERR,
3303                          "Can't support bigalloc feature without "
3304                          "extents feature\n");
3305                 return 0;
3306         }
3307
3308 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3309         if (!readonly && (ext4_has_feature_quota(sb) ||
3310                           ext4_has_feature_project(sb))) {
3311                 ext4_msg(sb, KERN_ERR,
3312                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3313                 return 0;
3314         }
3315 #endif  /* CONFIG_QUOTA */
3316         return 1;
3317 }
3318
3319 /*
3320  * This function is called once a day if we have errors logged
3321  * on the file system
3322  */
3323 static void print_daily_error_info(struct timer_list *t)
3324 {
3325         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3326         struct super_block *sb = sbi->s_sb;
3327         struct ext4_super_block *es = sbi->s_es;
3328
3329         if (es->s_error_count)
3330                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3331                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3332                          le32_to_cpu(es->s_error_count));
3333         if (es->s_first_error_time) {
3334                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3335                        sb->s_id,
3336                        ext4_get_tstamp(es, s_first_error_time),
3337                        (int) sizeof(es->s_first_error_func),
3338                        es->s_first_error_func,
3339                        le32_to_cpu(es->s_first_error_line));
3340                 if (es->s_first_error_ino)
3341                         printk(KERN_CONT ": inode %u",
3342                                le32_to_cpu(es->s_first_error_ino));
3343                 if (es->s_first_error_block)
3344                         printk(KERN_CONT ": block %llu", (unsigned long long)
3345                                le64_to_cpu(es->s_first_error_block));
3346                 printk(KERN_CONT "\n");
3347         }
3348         if (es->s_last_error_time) {
3349                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3350                        sb->s_id,
3351                        ext4_get_tstamp(es, s_last_error_time),
3352                        (int) sizeof(es->s_last_error_func),
3353                        es->s_last_error_func,
3354                        le32_to_cpu(es->s_last_error_line));
3355                 if (es->s_last_error_ino)
3356                         printk(KERN_CONT ": inode %u",
3357                                le32_to_cpu(es->s_last_error_ino));
3358                 if (es->s_last_error_block)
3359                         printk(KERN_CONT ": block %llu", (unsigned long long)
3360                                le64_to_cpu(es->s_last_error_block));
3361                 printk(KERN_CONT "\n");
3362         }
3363         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3364 }
3365
3366 /* Find next suitable group and run ext4_init_inode_table */
3367 static int ext4_run_li_request(struct ext4_li_request *elr)
3368 {
3369         struct ext4_group_desc *gdp = NULL;
3370         struct super_block *sb = elr->lr_super;
3371         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3372         ext4_group_t group = elr->lr_next_group;
3373         unsigned long timeout = 0;
3374         unsigned int prefetch_ios = 0;
3375         int ret = 0;
3376
3377         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3378                 elr->lr_next_group = ext4_mb_prefetch(sb, group,
3379                                 EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3380                 if (prefetch_ios)
3381                         ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3382                                               prefetch_ios);
3383                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3384                                             prefetch_ios);
3385                 if (group >= elr->lr_next_group) {
3386                         ret = 1;
3387                         if (elr->lr_first_not_zeroed != ngroups &&
3388                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3389                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3390                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3391                                 ret = 0;
3392                         }
3393                 }
3394                 return ret;
3395         }
3396
3397         for (; group < ngroups; group++) {
3398                 gdp = ext4_get_group_desc(sb, group, NULL);
3399                 if (!gdp) {
3400                         ret = 1;
3401                         break;
3402                 }
3403
3404                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3405                         break;
3406         }
3407
3408         if (group >= ngroups)
3409                 ret = 1;
3410
3411         if (!ret) {
3412                 timeout = jiffies;
3413                 ret = ext4_init_inode_table(sb, group,
3414                                             elr->lr_timeout ? 0 : 1);
3415                 trace_ext4_lazy_itable_init(sb, group);
3416                 if (elr->lr_timeout == 0) {
3417                         timeout = (jiffies - timeout) *
3418                                 EXT4_SB(elr->lr_super)->s_li_wait_mult;
3419                         elr->lr_timeout = timeout;
3420                 }
3421                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3422                 elr->lr_next_group = group + 1;
3423         }
3424         return ret;
3425 }
3426
3427 /*
3428  * Remove lr_request from the list_request and free the
3429  * request structure. Should be called with li_list_mtx held
3430  */
3431 static void ext4_remove_li_request(struct ext4_li_request *elr)
3432 {
3433         if (!elr)
3434                 return;
3435
3436         list_del(&elr->lr_request);
3437         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3438         kfree(elr);
3439 }
3440
3441 static void ext4_unregister_li_request(struct super_block *sb)
3442 {
3443         mutex_lock(&ext4_li_mtx);
3444         if (!ext4_li_info) {
3445                 mutex_unlock(&ext4_li_mtx);
3446                 return;
3447         }
3448
3449         mutex_lock(&ext4_li_info->li_list_mtx);
3450         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3451         mutex_unlock(&ext4_li_info->li_list_mtx);
3452         mutex_unlock(&ext4_li_mtx);
3453 }
3454
3455 static struct task_struct *ext4_lazyinit_task;
3456
3457 /*
3458  * This is the function where ext4lazyinit thread lives. It walks
3459  * through the request list searching for next scheduled filesystem.
3460  * When such a fs is found, run the lazy initialization request
3461  * (ext4_rn_li_request) and keep track of the time spend in this
3462  * function. Based on that time we compute next schedule time of
3463  * the request. When walking through the list is complete, compute
3464  * next waking time and put itself into sleep.
3465  */
3466 static int ext4_lazyinit_thread(void *arg)
3467 {
3468         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3469         struct list_head *pos, *n;
3470         struct ext4_li_request *elr;
3471         unsigned long next_wakeup, cur;
3472
3473         BUG_ON(NULL == eli);
3474
3475 cont_thread:
3476         while (true) {
3477                 next_wakeup = MAX_JIFFY_OFFSET;
3478
3479                 mutex_lock(&eli->li_list_mtx);
3480                 if (list_empty(&eli->li_request_list)) {
3481                         mutex_unlock(&eli->li_list_mtx);
3482                         goto exit_thread;
3483                 }
3484                 list_for_each_safe(pos, n, &eli->li_request_list) {
3485                         int err = 0;
3486                         int progress = 0;
3487                         elr = list_entry(pos, struct ext4_li_request,
3488                                          lr_request);
3489
3490                         if (time_before(jiffies, elr->lr_next_sched)) {
3491                                 if (time_before(elr->lr_next_sched, next_wakeup))
3492                                         next_wakeup = elr->lr_next_sched;
3493                                 continue;
3494                         }
3495                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3496                                 if (sb_start_write_trylock(elr->lr_super)) {
3497                                         progress = 1;
3498                                         /*
3499                                          * We hold sb->s_umount, sb can not
3500                                          * be removed from the list, it is
3501                                          * now safe to drop li_list_mtx
3502                                          */
3503                                         mutex_unlock(&eli->li_list_mtx);
3504                                         err = ext4_run_li_request(elr);
3505                                         sb_end_write(elr->lr_super);
3506                                         mutex_lock(&eli->li_list_mtx);
3507                                         n = pos->next;
3508                                 }
3509                                 up_read((&elr->lr_super->s_umount));
3510                         }
3511                         /* error, remove the lazy_init job */
3512                         if (err) {
3513                                 ext4_remove_li_request(elr);
3514                                 continue;
3515                         }
3516                         if (!progress) {
3517                                 elr->lr_next_sched = jiffies +
3518                                         (prandom_u32()
3519                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3520                         }
3521                         if (time_before(elr->lr_next_sched, next_wakeup))
3522                                 next_wakeup = elr->lr_next_sched;
3523                 }
3524                 mutex_unlock(&eli->li_list_mtx);
3525
3526                 try_to_freeze();
3527
3528                 cur = jiffies;
3529                 if ((time_after_eq(cur, next_wakeup)) ||
3530                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3531                         cond_resched();
3532                         continue;
3533                 }
3534
3535                 schedule_timeout_interruptible(next_wakeup - cur);
3536
3537                 if (kthread_should_stop()) {
3538                         ext4_clear_request_list();
3539                         goto exit_thread;
3540                 }
3541         }
3542
3543 exit_thread:
3544         /*
3545          * It looks like the request list is empty, but we need
3546          * to check it under the li_list_mtx lock, to prevent any
3547          * additions into it, and of course we should lock ext4_li_mtx
3548          * to atomically free the list and ext4_li_info, because at
3549          * this point another ext4 filesystem could be registering
3550          * new one.
3551          */
3552         mutex_lock(&ext4_li_mtx);
3553         mutex_lock(&eli->li_list_mtx);
3554         if (!list_empty(&eli->li_request_list)) {
3555                 mutex_unlock(&eli->li_list_mtx);
3556                 mutex_unlock(&ext4_li_mtx);
3557                 goto cont_thread;
3558         }
3559         mutex_unlock(&eli->li_list_mtx);
3560         kfree(ext4_li_info);
3561         ext4_li_info = NULL;
3562         mutex_unlock(&ext4_li_mtx);
3563
3564         return 0;
3565 }
3566
3567 static void ext4_clear_request_list(void)
3568 {
3569         struct list_head *pos, *n;
3570         struct ext4_li_request *elr;
3571
3572         mutex_lock(&ext4_li_info->li_list_mtx);
3573         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3574                 elr = list_entry(pos, struct ext4_li_request,
3575                                  lr_request);
3576                 ext4_remove_li_request(elr);
3577         }
3578         mutex_unlock(&ext4_li_info->li_list_mtx);
3579 }
3580
3581 static int ext4_run_lazyinit_thread(void)
3582 {
3583         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3584                                          ext4_li_info, "ext4lazyinit");
3585         if (IS_ERR(ext4_lazyinit_task)) {
3586                 int err = PTR_ERR(ext4_lazyinit_task);
3587                 ext4_clear_request_list();
3588                 kfree(ext4_li_info);
3589                 ext4_li_info = NULL;
3590                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3591                                  "initialization thread\n",
3592                                  err);
3593                 return err;
3594         }
3595         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3596         return 0;
3597 }
3598
3599 /*
3600  * Check whether it make sense to run itable init. thread or not.
3601  * If there is at least one uninitialized inode table, return
3602  * corresponding group number, else the loop goes through all
3603  * groups and return total number of groups.
3604  */
3605 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3606 {
3607         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3608         struct ext4_group_desc *gdp = NULL;
3609
3610         if (!ext4_has_group_desc_csum(sb))
3611                 return ngroups;
3612
3613         for (group = 0; group < ngroups; group++) {
3614                 gdp = ext4_get_group_desc(sb, group, NULL);
3615                 if (!gdp)
3616                         continue;
3617
3618                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3619                         break;
3620         }
3621
3622         return group;
3623 }
3624
3625 static int ext4_li_info_new(void)
3626 {
3627         struct ext4_lazy_init *eli = NULL;
3628
3629         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3630         if (!eli)
3631                 return -ENOMEM;
3632
3633         INIT_LIST_HEAD(&eli->li_request_list);
3634         mutex_init(&eli->li_list_mtx);
3635
3636         eli->li_state |= EXT4_LAZYINIT_QUIT;
3637
3638         ext4_li_info = eli;
3639
3640         return 0;
3641 }
3642
3643 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3644                                             ext4_group_t start)
3645 {
3646         struct ext4_li_request *elr;
3647
3648         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3649         if (!elr)
3650                 return NULL;
3651
3652         elr->lr_super = sb;
3653         elr->lr_first_not_zeroed = start;
3654         if (test_opt(sb, PREFETCH_BLOCK_BITMAPS))
3655                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3656         else {
3657                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3658                 elr->lr_next_group = start;
3659         }
3660
3661         /*
3662          * Randomize first schedule time of the request to
3663          * spread the inode table initialization requests
3664          * better.
3665          */
3666         elr->lr_next_sched = jiffies + (prandom_u32() %
3667                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3668         return elr;
3669 }
3670
3671 int ext4_register_li_request(struct super_block *sb,
3672                              ext4_group_t first_not_zeroed)
3673 {
3674         struct ext4_sb_info *sbi = EXT4_SB(sb);
3675         struct ext4_li_request *elr = NULL;
3676         ext4_group_t ngroups = sbi->s_groups_count;
3677         int ret = 0;
3678
3679         mutex_lock(&ext4_li_mtx);
3680         if (sbi->s_li_request != NULL) {
3681                 /*
3682                  * Reset timeout so it can be computed again, because
3683                  * s_li_wait_mult might have changed.
3684                  */
3685                 sbi->s_li_request->lr_timeout = 0;
3686                 goto out;
3687         }
3688
3689         if (!test_opt(sb, PREFETCH_BLOCK_BITMAPS) &&
3690             (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3691              !test_opt(sb, INIT_INODE_TABLE)))
3692                 goto out;
3693
3694         elr = ext4_li_request_new(sb, first_not_zeroed);
3695         if (!elr) {
3696                 ret = -ENOMEM;
3697                 goto out;
3698         }
3699
3700         if (NULL == ext4_li_info) {
3701                 ret = ext4_li_info_new();
3702                 if (ret)
3703                         goto out;
3704         }
3705
3706         mutex_lock(&ext4_li_info->li_list_mtx);
3707         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3708         mutex_unlock(&ext4_li_info->li_list_mtx);
3709
3710         sbi->s_li_request = elr;
3711         /*
3712          * set elr to NULL here since it has been inserted to
3713          * the request_list and the removal and free of it is
3714          * handled by ext4_clear_request_list from now on.
3715          */
3716         elr = NULL;
3717
3718         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3719                 ret = ext4_run_lazyinit_thread();
3720                 if (ret)
3721                         goto out;
3722         }
3723 out:
3724         mutex_unlock(&ext4_li_mtx);
3725         if (ret)
3726                 kfree(elr);
3727         return ret;
3728 }
3729
3730 /*
3731  * We do not need to lock anything since this is called on
3732  * module unload.
3733  */
3734 static void ext4_destroy_lazyinit_thread(void)
3735 {
3736         /*
3737          * If thread exited earlier
3738          * there's nothing to be done.
3739          */
3740         if (!ext4_li_info || !ext4_lazyinit_task)
3741                 return;
3742
3743         kthread_stop(ext4_lazyinit_task);
3744 }
3745
3746 static int set_journal_csum_feature_set(struct super_block *sb)
3747 {
3748         int ret = 1;
3749         int compat, incompat;
3750         struct ext4_sb_info *sbi = EXT4_SB(sb);
3751
3752         if (ext4_has_metadata_csum(sb)) {
3753                 /* journal checksum v3 */
3754                 compat = 0;
3755                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3756         } else {
3757                 /* journal checksum v1 */
3758                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3759                 incompat = 0;
3760         }
3761
3762         jbd2_journal_clear_features(sbi->s_journal,
3763                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3764                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3765                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3766         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3767                 ret = jbd2_journal_set_features(sbi->s_journal,
3768                                 compat, 0,
3769                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3770                                 incompat);
3771         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3772                 ret = jbd2_journal_set_features(sbi->s_journal,
3773                                 compat, 0,
3774                                 incompat);
3775                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3776                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3777         } else {
3778                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3779                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3780         }
3781
3782         return ret;
3783 }
3784
3785 /*
3786  * Note: calculating the overhead so we can be compatible with
3787  * historical BSD practice is quite difficult in the face of
3788  * clusters/bigalloc.  This is because multiple metadata blocks from
3789  * different block group can end up in the same allocation cluster.
3790  * Calculating the exact overhead in the face of clustered allocation
3791  * requires either O(all block bitmaps) in memory or O(number of block
3792  * groups**2) in time.  We will still calculate the superblock for
3793  * older file systems --- and if we come across with a bigalloc file
3794  * system with zero in s_overhead_clusters the estimate will be close to
3795  * correct especially for very large cluster sizes --- but for newer
3796  * file systems, it's better to calculate this figure once at mkfs
3797  * time, and store it in the superblock.  If the superblock value is
3798  * present (even for non-bigalloc file systems), we will use it.
3799  */
3800 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3801                           char *buf)
3802 {
3803         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3804         struct ext4_group_desc  *gdp;
3805         ext4_fsblk_t            first_block, last_block, b;
3806         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3807         int                     s, j, count = 0;
3808
3809         if (!ext4_has_feature_bigalloc(sb))
3810                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3811                         sbi->s_itb_per_group + 2);
3812
3813         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3814                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3815         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3816         for (i = 0; i < ngroups; i++) {
3817                 gdp = ext4_get_group_desc(sb, i, NULL);
3818                 b = ext4_block_bitmap(sb, gdp);
3819                 if (b >= first_block && b <= last_block) {
3820                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3821                         count++;
3822                 }
3823                 b = ext4_inode_bitmap(sb, gdp);
3824                 if (b >= first_block && b <= last_block) {
3825                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3826                         count++;
3827                 }
3828                 b = ext4_inode_table(sb, gdp);
3829                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3830                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3831                                 int c = EXT4_B2C(sbi, b - first_block);
3832                                 ext4_set_bit(c, buf);
3833                                 count++;
3834                         }
3835                 if (i != grp)
3836                         continue;
3837                 s = 0;
3838                 if (ext4_bg_has_super(sb, grp)) {
3839                         ext4_set_bit(s++, buf);
3840                         count++;
3841                 }
3842                 j = ext4_bg_num_gdb(sb, grp);
3843                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3844                         ext4_error(sb, "Invalid number of block group "
3845                                    "descriptor blocks: %d", j);
3846                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3847                 }
3848                 count += j;
3849                 for (; j > 0; j--)
3850                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3851         }
3852         if (!count)
3853                 return 0;
3854         return EXT4_CLUSTERS_PER_GROUP(sb) -
3855                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3856 }
3857
3858 /*
3859  * Compute the overhead and stash it in sbi->s_overhead
3860  */
3861 int ext4_calculate_overhead(struct super_block *sb)
3862 {
3863         struct ext4_sb_info *sbi = EXT4_SB(sb);
3864         struct ext4_super_block *es = sbi->s_es;
3865         struct inode *j_inode;
3866         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3867         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3868         ext4_fsblk_t overhead = 0;
3869         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3870
3871         if (!buf)
3872                 return -ENOMEM;
3873
3874         /*
3875          * Compute the overhead (FS structures).  This is constant
3876          * for a given filesystem unless the number of block groups
3877          * changes so we cache the previous value until it does.
3878          */
3879
3880         /*
3881          * All of the blocks before first_data_block are overhead
3882          */
3883         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3884
3885         /*
3886          * Add the overhead found in each block group
3887          */
3888         for (i = 0; i < ngroups; i++) {
3889                 int blks;
3890
3891                 blks = count_overhead(sb, i, buf);
3892                 overhead += blks;
3893                 if (blks)
3894                         memset(buf, 0, PAGE_SIZE);
3895                 cond_resched();
3896         }
3897
3898         /*
3899          * Add the internal journal blocks whether the journal has been
3900          * loaded or not
3901          */
3902         if (sbi->s_journal && !sbi->s_journal_bdev)
3903                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
3904         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3905                 /* j_inum for internal journal is non-zero */
3906                 j_inode = ext4_get_journal_inode(sb, j_inum);
3907                 if (j_inode) {
3908                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3909                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3910                         iput(j_inode);
3911                 } else {
3912                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3913                 }
3914         }
3915         sbi->s_overhead = overhead;
3916         smp_wmb();
3917         free_page((unsigned long) buf);
3918         return 0;
3919 }
3920
3921 static void ext4_set_resv_clusters(struct super_block *sb)
3922 {
3923         ext4_fsblk_t resv_clusters;
3924         struct ext4_sb_info *sbi = EXT4_SB(sb);
3925
3926         /*
3927          * There's no need to reserve anything when we aren't using extents.
3928          * The space estimates are exact, there are no unwritten extents,
3929          * hole punching doesn't need new metadata... This is needed especially
3930          * to keep ext2/3 backward compatibility.
3931          */
3932         if (!ext4_has_feature_extents(sb))
3933                 return;
3934         /*
3935          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3936          * This should cover the situations where we can not afford to run
3937          * out of space like for example punch hole, or converting
3938          * unwritten extents in delalloc path. In most cases such
3939          * allocation would require 1, or 2 blocks, higher numbers are
3940          * very rare.
3941          */
3942         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3943                          sbi->s_cluster_bits);
3944
3945         do_div(resv_clusters, 50);
3946         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3947
3948         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3949 }
3950
3951 static const char *ext4_quota_mode(struct super_block *sb)
3952 {
3953 #ifdef CONFIG_QUOTA
3954         if (!ext4_quota_capable(sb))
3955                 return "none";
3956
3957         if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
3958                 return "journalled";
3959         else
3960                 return "writeback";
3961 #else
3962         return "disabled";
3963 #endif
3964 }
3965
3966 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3967 {
3968         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3969         char *orig_data = kstrdup(data, GFP_KERNEL);
3970         struct buffer_head *bh, **group_desc;
3971         struct ext4_super_block *es = NULL;
3972         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3973         struct flex_groups **flex_groups;
3974         ext4_fsblk_t block;
3975         ext4_fsblk_t sb_block = get_sb_block(&data);
3976         ext4_fsblk_t logical_sb_block;
3977         unsigned long offset = 0;
3978         unsigned long journal_devnum = 0;
3979         unsigned long def_mount_opts;
3980         struct inode *root;
3981         const char *descr;
3982         int ret = -ENOMEM;
3983         int blocksize, clustersize;
3984         unsigned int db_count;
3985         unsigned int i;
3986         int needs_recovery, has_huge_files;
3987         __u64 blocks_count;
3988         int err = 0;
3989         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3990         ext4_group_t first_not_zeroed;
3991
3992         if ((data && !orig_data) || !sbi)
3993                 goto out_free_base;
3994
3995         sbi->s_daxdev = dax_dev;
3996         sbi->s_blockgroup_lock =
3997                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3998         if (!sbi->s_blockgroup_lock)
3999                 goto out_free_base;
4000
4001         sb->s_fs_info = sbi;
4002         sbi->s_sb = sb;
4003         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
4004         sbi->s_sb_block = sb_block;
4005         if (sb->s_bdev->bd_part)
4006                 sbi->s_sectors_written_start =
4007                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
4008
4009         /* Cleanup superblock name */
4010         strreplace(sb->s_id, '/', '!');
4011
4012         /* -EINVAL is default */
4013         ret = -EINVAL;
4014         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
4015         if (!blocksize) {
4016                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
4017                 goto out_fail;
4018         }
4019
4020         /*
4021          * The ext4 superblock will not be buffer aligned for other than 1kB
4022          * block sizes.  We need to calculate the offset from buffer start.
4023          */
4024         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
4025                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4026                 offset = do_div(logical_sb_block, blocksize);
4027         } else {
4028                 logical_sb_block = sb_block;
4029         }
4030
4031         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4032         if (IS_ERR(bh)) {
4033                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
4034                 ret = PTR_ERR(bh);
4035                 goto out_fail;
4036         }
4037         /*
4038          * Note: s_es must be initialized as soon as possible because
4039          *       some ext4 macro-instructions depend on its value
4040          */
4041         es = (struct ext4_super_block *) (bh->b_data + offset);
4042         sbi->s_es = es;
4043         sb->s_magic = le16_to_cpu(es->s_magic);
4044         if (sb->s_magic != EXT4_SUPER_MAGIC)
4045                 goto cantfind_ext4;
4046         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
4047
4048         /* Warn if metadata_csum and gdt_csum are both set. */
4049         if (ext4_has_feature_metadata_csum(sb) &&
4050             ext4_has_feature_gdt_csum(sb))
4051                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4052                              "redundant flags; please run fsck.");
4053
4054         /* Check for a known checksum algorithm */
4055         if (!ext4_verify_csum_type(sb, es)) {
4056                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4057                          "unknown checksum algorithm.");
4058                 silent = 1;
4059                 goto cantfind_ext4;
4060         }
4061
4062         /* Load the checksum driver */
4063         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4064         if (IS_ERR(sbi->s_chksum_driver)) {
4065                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4066                 ret = PTR_ERR(sbi->s_chksum_driver);
4067                 sbi->s_chksum_driver = NULL;
4068                 goto failed_mount;
4069         }
4070
4071         /* Check superblock checksum */
4072         if (!ext4_superblock_csum_verify(sb, es)) {
4073                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4074                          "invalid superblock checksum.  Run e2fsck?");
4075                 silent = 1;
4076                 ret = -EFSBADCRC;
4077                 goto cantfind_ext4;
4078         }
4079
4080         /* Precompute checksum seed for all metadata */
4081         if (ext4_has_feature_csum_seed(sb))
4082                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4083         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4084                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4085                                                sizeof(es->s_uuid));
4086
4087         /* Set defaults before we parse the mount options */
4088         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4089         set_opt(sb, INIT_INODE_TABLE);
4090         if (def_mount_opts & EXT4_DEFM_DEBUG)
4091                 set_opt(sb, DEBUG);
4092         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4093                 set_opt(sb, GRPID);
4094         if (def_mount_opts & EXT4_DEFM_UID16)
4095                 set_opt(sb, NO_UID32);
4096         /* xattr user namespace & acls are now defaulted on */
4097         set_opt(sb, XATTR_USER);
4098 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4099         set_opt(sb, POSIX_ACL);
4100 #endif
4101         if (ext4_has_feature_fast_commit(sb))
4102                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4103         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4104         if (ext4_has_metadata_csum(sb))
4105                 set_opt(sb, JOURNAL_CHECKSUM);
4106
4107         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4108                 set_opt(sb, JOURNAL_DATA);
4109         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4110                 set_opt(sb, ORDERED_DATA);
4111         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4112                 set_opt(sb, WRITEBACK_DATA);
4113
4114         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
4115                 set_opt(sb, ERRORS_PANIC);
4116         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
4117                 set_opt(sb, ERRORS_CONT);
4118         else
4119                 set_opt(sb, ERRORS_RO);
4120         /* block_validity enabled by default; disable with noblock_validity */
4121         set_opt(sb, BLOCK_VALIDITY);
4122         if (def_mount_opts & EXT4_DEFM_DISCARD)
4123                 set_opt(sb, DISCARD);
4124
4125         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
4126         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
4127         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
4128         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
4129         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
4130
4131         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4132                 set_opt(sb, BARRIER);
4133
4134         /*
4135          * enable delayed allocation by default
4136          * Use -o nodelalloc to turn it off
4137          */
4138         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4139             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4140                 set_opt(sb, DELALLOC);
4141
4142         /*
4143          * set default s_li_wait_mult for lazyinit, for the case there is
4144          * no mount option specified.
4145          */
4146         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
4147
4148         if (le32_to_cpu(es->s_log_block_size) >
4149             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4150                 ext4_msg(sb, KERN_ERR,
4151                          "Invalid log block size: %u",
4152                          le32_to_cpu(es->s_log_block_size));
4153                 goto failed_mount;
4154         }
4155         if (le32_to_cpu(es->s_log_cluster_size) >
4156             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4157                 ext4_msg(sb, KERN_ERR,
4158                          "Invalid log cluster size: %u",
4159                          le32_to_cpu(es->s_log_cluster_size));
4160                 goto failed_mount;
4161         }
4162
4163         blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
4164
4165         if (blocksize == PAGE_SIZE)
4166                 set_opt(sb, DIOREAD_NOLOCK);
4167
4168         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4169                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4170                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4171         } else {
4172                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4173                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4174                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4175                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4176                                  sbi->s_first_ino);
4177                         goto failed_mount;
4178                 }
4179                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4180                     (!is_power_of_2(sbi->s_inode_size)) ||
4181                     (sbi->s_inode_size > blocksize)) {
4182                         ext4_msg(sb, KERN_ERR,
4183                                "unsupported inode size: %d",
4184                                sbi->s_inode_size);
4185                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
4186                         goto failed_mount;
4187                 }
4188                 /*
4189                  * i_atime_extra is the last extra field available for
4190                  * [acm]times in struct ext4_inode. Checking for that
4191                  * field should suffice to ensure we have extra space
4192                  * for all three.
4193                  */
4194                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4195                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4196                         sb->s_time_gran = 1;
4197                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4198                 } else {
4199                         sb->s_time_gran = NSEC_PER_SEC;
4200                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4201                 }
4202                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4203         }
4204         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4205                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4206                         EXT4_GOOD_OLD_INODE_SIZE;
4207                 if (ext4_has_feature_extra_isize(sb)) {
4208                         unsigned v, max = (sbi->s_inode_size -
4209                                            EXT4_GOOD_OLD_INODE_SIZE);
4210
4211                         v = le16_to_cpu(es->s_want_extra_isize);
4212                         if (v > max) {
4213                                 ext4_msg(sb, KERN_ERR,
4214                                          "bad s_want_extra_isize: %d", v);
4215                                 goto failed_mount;
4216                         }
4217                         if (sbi->s_want_extra_isize < v)
4218                                 sbi->s_want_extra_isize = v;
4219
4220                         v = le16_to_cpu(es->s_min_extra_isize);
4221                         if (v > max) {
4222                                 ext4_msg(sb, KERN_ERR,
4223                                          "bad s_min_extra_isize: %d", v);
4224                                 goto failed_mount;
4225                         }
4226                         if (sbi->s_want_extra_isize < v)
4227                                 sbi->s_want_extra_isize = v;
4228                 }
4229         }
4230
4231         if (sbi->s_es->s_mount_opts[0]) {
4232                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
4233                                               sizeof(sbi->s_es->s_mount_opts),
4234                                               GFP_KERNEL);
4235                 if (!s_mount_opts)
4236                         goto failed_mount;
4237                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
4238                                    &journal_ioprio, 0)) {
4239                         ext4_msg(sb, KERN_WARNING,
4240                                  "failed to parse options in superblock: %s",
4241                                  s_mount_opts);
4242                 }
4243                 kfree(s_mount_opts);
4244         }
4245         sbi->s_def_mount_opt = sbi->s_mount_opt;
4246         if (!parse_options((char *) data, sb, &journal_devnum,
4247                            &journal_ioprio, 0))
4248                 goto failed_mount;
4249
4250 #ifdef CONFIG_UNICODE
4251         if (ext4_has_feature_casefold(sb) && !sb->s_encoding) {
4252                 const struct ext4_sb_encodings *encoding_info;
4253                 struct unicode_map *encoding;
4254                 __u16 encoding_flags;
4255
4256                 if (ext4_has_feature_encrypt(sb)) {
4257                         ext4_msg(sb, KERN_ERR,
4258                                  "Can't mount with encoding and encryption");
4259                         goto failed_mount;
4260                 }
4261
4262                 if (ext4_sb_read_encoding(es, &encoding_info,
4263                                           &encoding_flags)) {
4264                         ext4_msg(sb, KERN_ERR,
4265                                  "Encoding requested by superblock is unknown");
4266                         goto failed_mount;
4267                 }
4268
4269                 encoding = utf8_load(encoding_info->version);
4270                 if (IS_ERR(encoding)) {
4271                         ext4_msg(sb, KERN_ERR,
4272                                  "can't mount with superblock charset: %s-%s "
4273                                  "not supported by the kernel. flags: 0x%x.",
4274                                  encoding_info->name, encoding_info->version,
4275                                  encoding_flags);
4276                         goto failed_mount;
4277                 }
4278                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4279                          "%s-%s with flags 0x%hx", encoding_info->name,
4280                          encoding_info->version?:"\b", encoding_flags);
4281
4282                 sb->s_encoding = encoding;
4283                 sb->s_encoding_flags = encoding_flags;
4284         }
4285 #endif
4286
4287         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4288                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, O_DIRECT and fast_commit support!\n");
4289                 /* can't mount with both data=journal and dioread_nolock. */
4290                 clear_opt(sb, DIOREAD_NOLOCK);
4291                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4292                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4293                         ext4_msg(sb, KERN_ERR, "can't mount with "
4294                                  "both data=journal and delalloc");
4295                         goto failed_mount;
4296                 }
4297                 if (test_opt(sb, DAX_ALWAYS)) {
4298                         ext4_msg(sb, KERN_ERR, "can't mount with "
4299                                  "both data=journal and dax");
4300                         goto failed_mount;
4301                 }
4302                 if (ext4_has_feature_encrypt(sb)) {
4303                         ext4_msg(sb, KERN_WARNING,
4304                                  "encrypted files will use data=ordered "
4305                                  "instead of data journaling mode");
4306                 }
4307                 if (test_opt(sb, DELALLOC))
4308                         clear_opt(sb, DELALLOC);
4309         } else {
4310                 sb->s_iflags |= SB_I_CGROUPWB;
4311         }
4312
4313         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4314                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4315
4316         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4317             (ext4_has_compat_features(sb) ||
4318              ext4_has_ro_compat_features(sb) ||
4319              ext4_has_incompat_features(sb)))
4320                 ext4_msg(sb, KERN_WARNING,
4321                        "feature flags set on rev 0 fs, "
4322                        "running e2fsck is recommended");
4323
4324         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4325                 set_opt2(sb, HURD_COMPAT);
4326                 if (ext4_has_feature_64bit(sb)) {
4327                         ext4_msg(sb, KERN_ERR,
4328                                  "The Hurd can't support 64-bit file systems");
4329                         goto failed_mount;
4330                 }
4331
4332                 /*
4333                  * ea_inode feature uses l_i_version field which is not
4334                  * available in HURD_COMPAT mode.
4335                  */
4336                 if (ext4_has_feature_ea_inode(sb)) {
4337                         ext4_msg(sb, KERN_ERR,
4338                                  "ea_inode feature is not supported for Hurd");
4339                         goto failed_mount;
4340                 }
4341         }
4342
4343         if (IS_EXT2_SB(sb)) {
4344                 if (ext2_feature_set_ok(sb))
4345                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4346                                  "using the ext4 subsystem");
4347                 else {
4348                         /*
4349                          * If we're probing be silent, if this looks like
4350                          * it's actually an ext[34] filesystem.
4351                          */
4352                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4353                                 goto failed_mount;
4354                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4355                                  "to feature incompatibilities");
4356                         goto failed_mount;
4357                 }
4358         }
4359
4360         if (IS_EXT3_SB(sb)) {
4361                 if (ext3_feature_set_ok(sb))
4362                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4363                                  "using the ext4 subsystem");
4364                 else {
4365                         /*
4366                          * If we're probing be silent, if this looks like
4367                          * it's actually an ext4 filesystem.
4368                          */
4369                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4370                                 goto failed_mount;
4371                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4372                                  "to feature incompatibilities");
4373                         goto failed_mount;
4374                 }
4375         }
4376
4377         /*
4378          * Check feature flags regardless of the revision level, since we
4379          * previously didn't change the revision level when setting the flags,
4380          * so there is a chance incompat flags are set on a rev 0 filesystem.
4381          */
4382         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4383                 goto failed_mount;
4384
4385         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4386                 ext4_msg(sb, KERN_ERR,
4387                          "Number of reserved GDT blocks insanely large: %d",
4388                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4389                 goto failed_mount;
4390         }
4391
4392         if (bdev_dax_supported(sb->s_bdev, blocksize))
4393                 set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4394
4395         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4396                 if (ext4_has_feature_inline_data(sb)) {
4397                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4398                                         " that may contain inline data");
4399                         goto failed_mount;
4400                 }
4401                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4402                         ext4_msg(sb, KERN_ERR,
4403                                 "DAX unsupported by block device.");
4404                         goto failed_mount;
4405                 }
4406         }
4407
4408         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4409                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4410                          es->s_encryption_level);
4411                 goto failed_mount;
4412         }
4413
4414         if (sb->s_blocksize != blocksize) {
4415                 /* Validate the filesystem blocksize */
4416                 if (!sb_set_blocksize(sb, blocksize)) {
4417                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4418                                         blocksize);
4419                         goto failed_mount;
4420                 }
4421
4422                 brelse(bh);
4423                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4424                 offset = do_div(logical_sb_block, blocksize);
4425                 bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4426                 if (IS_ERR(bh)) {
4427                         ext4_msg(sb, KERN_ERR,
4428                                "Can't read superblock on 2nd try");
4429                         ret = PTR_ERR(bh);
4430                         bh = NULL;
4431                         goto failed_mount;
4432                 }
4433                 es = (struct ext4_super_block *)(bh->b_data + offset);
4434                 sbi->s_es = es;
4435                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4436                         ext4_msg(sb, KERN_ERR,
4437                                "Magic mismatch, very weird!");
4438                         goto failed_mount;
4439                 }
4440         }
4441
4442         has_huge_files = ext4_has_feature_huge_file(sb);
4443         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4444                                                       has_huge_files);
4445         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4446
4447         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4448         if (ext4_has_feature_64bit(sb)) {
4449                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4450                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4451                     !is_power_of_2(sbi->s_desc_size)) {
4452                         ext4_msg(sb, KERN_ERR,
4453                                "unsupported descriptor size %lu",
4454                                sbi->s_desc_size);
4455                         goto failed_mount;
4456                 }
4457         } else
4458                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4459
4460         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4461         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4462
4463         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4464         if (sbi->s_inodes_per_block == 0)
4465                 goto cantfind_ext4;
4466         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4467             sbi->s_inodes_per_group > blocksize * 8) {
4468                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4469                          sbi->s_inodes_per_group);
4470                 goto failed_mount;
4471         }
4472         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4473                                         sbi->s_inodes_per_block;
4474         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4475         sbi->s_sbh = bh;
4476         sbi->s_mount_state = le16_to_cpu(es->s_state);
4477         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4478         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4479
4480         for (i = 0; i < 4; i++)
4481                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4482         sbi->s_def_hash_version = es->s_def_hash_version;
4483         if (ext4_has_feature_dir_index(sb)) {
4484                 i = le32_to_cpu(es->s_flags);
4485                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4486                         sbi->s_hash_unsigned = 3;
4487                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4488 #ifdef __CHAR_UNSIGNED__
4489                         if (!sb_rdonly(sb))
4490                                 es->s_flags |=
4491                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4492                         sbi->s_hash_unsigned = 3;
4493 #else
4494                         if (!sb_rdonly(sb))
4495                                 es->s_flags |=
4496                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4497 #endif
4498                 }
4499         }
4500
4501         /* Handle clustersize */
4502         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4503         if (ext4_has_feature_bigalloc(sb)) {
4504                 if (clustersize < blocksize) {
4505                         ext4_msg(sb, KERN_ERR,
4506                                  "cluster size (%d) smaller than "
4507                                  "block size (%d)", clustersize, blocksize);
4508                         goto failed_mount;
4509                 }
4510                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4511                         le32_to_cpu(es->s_log_block_size);
4512                 sbi->s_clusters_per_group =
4513                         le32_to_cpu(es->s_clusters_per_group);
4514                 if (sbi->s_clusters_per_group > blocksize * 8) {
4515                         ext4_msg(sb, KERN_ERR,
4516                                  "#clusters per group too big: %lu",
4517                                  sbi->s_clusters_per_group);
4518                         goto failed_mount;
4519                 }
4520                 if (sbi->s_blocks_per_group !=
4521                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4522                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4523                                  "clusters per group (%lu) inconsistent",
4524                                  sbi->s_blocks_per_group,
4525                                  sbi->s_clusters_per_group);
4526                         goto failed_mount;
4527                 }
4528         } else {
4529                 if (clustersize != blocksize) {
4530                         ext4_msg(sb, KERN_ERR,
4531                                  "fragment/cluster size (%d) != "
4532                                  "block size (%d)", clustersize, blocksize);
4533                         goto failed_mount;
4534                 }
4535                 if (sbi->s_blocks_per_group > blocksize * 8) {
4536                         ext4_msg(sb, KERN_ERR,
4537                                  "#blocks per group too big: %lu",
4538                                  sbi->s_blocks_per_group);
4539                         goto failed_mount;
4540                 }
4541                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4542                 sbi->s_cluster_bits = 0;
4543         }
4544         sbi->s_cluster_ratio = clustersize / blocksize;
4545
4546         /* Do we have standard group size of clustersize * 8 blocks ? */
4547         if (sbi->s_blocks_per_group == clustersize << 3)
4548                 set_opt2(sb, STD_GROUP_SIZE);
4549
4550         /*
4551          * Test whether we have more sectors than will fit in sector_t,
4552          * and whether the max offset is addressable by the page cache.
4553          */
4554         err = generic_check_addressable(sb->s_blocksize_bits,
4555                                         ext4_blocks_count(es));
4556         if (err) {
4557                 ext4_msg(sb, KERN_ERR, "filesystem"
4558                          " too large to mount safely on this system");
4559                 goto failed_mount;
4560         }
4561
4562         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4563                 goto cantfind_ext4;
4564
4565         /* check blocks count against device size */
4566         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4567         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4568                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4569                        "exceeds size of device (%llu blocks)",
4570                        ext4_blocks_count(es), blocks_count);
4571                 goto failed_mount;
4572         }
4573
4574         /*
4575          * It makes no sense for the first data block to be beyond the end
4576          * of the filesystem.
4577          */
4578         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4579                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4580                          "block %u is beyond end of filesystem (%llu)",
4581                          le32_to_cpu(es->s_first_data_block),
4582                          ext4_blocks_count(es));
4583                 goto failed_mount;
4584         }
4585         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4586             (sbi->s_cluster_ratio == 1)) {
4587                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4588                          "block is 0 with a 1k block and cluster size");
4589                 goto failed_mount;
4590         }
4591
4592         blocks_count = (ext4_blocks_count(es) -
4593                         le32_to_cpu(es->s_first_data_block) +
4594                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4595         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4596         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4597                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4598                        "(block count %llu, first data block %u, "
4599                        "blocks per group %lu)", blocks_count,
4600                        ext4_blocks_count(es),
4601                        le32_to_cpu(es->s_first_data_block),
4602                        EXT4_BLOCKS_PER_GROUP(sb));
4603                 goto failed_mount;
4604         }
4605         sbi->s_groups_count = blocks_count;
4606         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4607                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4608         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4609             le32_to_cpu(es->s_inodes_count)) {
4610                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4611                          le32_to_cpu(es->s_inodes_count),
4612                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4613                 ret = -EINVAL;
4614                 goto failed_mount;
4615         }
4616         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4617                    EXT4_DESC_PER_BLOCK(sb);
4618         if (ext4_has_feature_meta_bg(sb)) {
4619                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4620                         ext4_msg(sb, KERN_WARNING,
4621                                  "first meta block group too large: %u "
4622                                  "(group descriptor block count %u)",
4623                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4624                         goto failed_mount;
4625                 }
4626         }
4627         rcu_assign_pointer(sbi->s_group_desc,
4628                            kvmalloc_array(db_count,
4629                                           sizeof(struct buffer_head *),
4630                                           GFP_KERNEL));
4631         if (sbi->s_group_desc == NULL) {
4632                 ext4_msg(sb, KERN_ERR, "not enough memory");
4633                 ret = -ENOMEM;
4634                 goto failed_mount;
4635         }
4636
4637         bgl_lock_init(sbi->s_blockgroup_lock);
4638
4639         /* Pre-read the descriptors into the buffer cache */
4640         for (i = 0; i < db_count; i++) {
4641                 block = descriptor_loc(sb, logical_sb_block, i);
4642                 ext4_sb_breadahead_unmovable(sb, block);
4643         }
4644
4645         for (i = 0; i < db_count; i++) {
4646                 struct buffer_head *bh;
4647
4648                 block = descriptor_loc(sb, logical_sb_block, i);
4649                 bh = ext4_sb_bread_unmovable(sb, block);
4650                 if (IS_ERR(bh)) {
4651                         ext4_msg(sb, KERN_ERR,
4652                                "can't read group descriptor %d", i);
4653                         db_count = i;
4654                         ret = PTR_ERR(bh);
4655                         goto failed_mount2;
4656                 }
4657                 rcu_read_lock();
4658                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4659                 rcu_read_unlock();
4660         }
4661         sbi->s_gdb_count = db_count;
4662         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4663                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4664                 ret = -EFSCORRUPTED;
4665                 goto failed_mount2;
4666         }
4667
4668         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4669
4670         /* Register extent status tree shrinker */
4671         if (ext4_es_register_shrinker(sbi))
4672                 goto failed_mount3;
4673
4674         sbi->s_stripe = ext4_get_stripe_size(sbi);
4675         sbi->s_extent_max_zeroout_kb = 32;
4676
4677         /*
4678          * set up enough so that it can read an inode
4679          */
4680         sb->s_op = &ext4_sops;
4681         sb->s_export_op = &ext4_export_ops;
4682         sb->s_xattr = ext4_xattr_handlers;
4683 #ifdef CONFIG_FS_ENCRYPTION
4684         sb->s_cop = &ext4_cryptops;
4685 #endif
4686 #ifdef CONFIG_FS_VERITY
4687         sb->s_vop = &ext4_verityops;
4688 #endif
4689 #ifdef CONFIG_QUOTA
4690         sb->dq_op = &ext4_quota_operations;
4691         if (ext4_has_feature_quota(sb))
4692                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4693         else
4694                 sb->s_qcop = &ext4_qctl_operations;
4695         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4696 #endif
4697         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4698
4699         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4700         mutex_init(&sbi->s_orphan_lock);
4701
4702         /* Initialize fast commit stuff */
4703         atomic_set(&sbi->s_fc_subtid, 0);
4704         atomic_set(&sbi->s_fc_ineligible_updates, 0);
4705         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4706         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4707         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4708         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4709         sbi->s_fc_bytes = 0;
4710         ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
4711         ext4_clear_mount_flag(sb, EXT4_MF_FC_COMMITTING);
4712         spin_lock_init(&sbi->s_fc_lock);
4713         memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4714         sbi->s_fc_replay_state.fc_regions = NULL;
4715         sbi->s_fc_replay_state.fc_regions_size = 0;
4716         sbi->s_fc_replay_state.fc_regions_used = 0;
4717         sbi->s_fc_replay_state.fc_regions_valid = 0;
4718         sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4719         sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4720         sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4721
4722         sb->s_root = NULL;
4723
4724         needs_recovery = (es->s_last_orphan != 0 ||
4725                           ext4_has_feature_journal_needs_recovery(sb));
4726
4727         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4728                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4729                         goto failed_mount3a;
4730
4731         /*
4732          * The first inode we look at is the journal inode.  Don't try
4733          * root first: it may be modified in the journal!
4734          */
4735         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4736                 err = ext4_load_journal(sb, es, journal_devnum);
4737                 if (err)
4738                         goto failed_mount3a;
4739         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4740                    ext4_has_feature_journal_needs_recovery(sb)) {
4741                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4742                        "suppressed and not mounted read-only");
4743                 goto failed_mount_wq;
4744         } else {
4745                 /* Nojournal mode, all journal mount options are illegal */
4746                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4747                         ext4_msg(sb, KERN_ERR, "can't mount with "
4748                                  "journal_checksum, fs mounted w/o journal");
4749                         goto failed_mount_wq;
4750                 }
4751                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4752                         ext4_msg(sb, KERN_ERR, "can't mount with "
4753                                  "journal_async_commit, fs mounted w/o journal");
4754                         goto failed_mount_wq;
4755                 }
4756                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4757                         ext4_msg(sb, KERN_ERR, "can't mount with "
4758                                  "commit=%lu, fs mounted w/o journal",
4759                                  sbi->s_commit_interval / HZ);
4760                         goto failed_mount_wq;
4761                 }
4762                 if (EXT4_MOUNT_DATA_FLAGS &
4763                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4764                         ext4_msg(sb, KERN_ERR, "can't mount with "
4765                                  "data=, fs mounted w/o journal");
4766                         goto failed_mount_wq;
4767                 }
4768                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4769                 clear_opt(sb, JOURNAL_CHECKSUM);
4770                 clear_opt(sb, DATA_FLAGS);
4771                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4772                 sbi->s_journal = NULL;
4773                 needs_recovery = 0;
4774                 goto no_journal;
4775         }
4776
4777         if (ext4_has_feature_64bit(sb) &&
4778             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4779                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4780                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4781                 goto failed_mount_wq;
4782         }
4783
4784         if (!set_journal_csum_feature_set(sb)) {
4785                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4786                          "feature set");
4787                 goto failed_mount_wq;
4788         }
4789
4790         if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4791                 !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4792                                           JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
4793                 ext4_msg(sb, KERN_ERR,
4794                         "Failed to set fast commit journal feature");
4795                 goto failed_mount_wq;
4796         }
4797
4798         /* We have now updated the journal if required, so we can
4799          * validate the data journaling mode. */
4800         switch (test_opt(sb, DATA_FLAGS)) {
4801         case 0:
4802                 /* No mode set, assume a default based on the journal
4803                  * capabilities: ORDERED_DATA if the journal can
4804                  * cope, else JOURNAL_DATA
4805                  */
4806                 if (jbd2_journal_check_available_features
4807                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4808                         set_opt(sb, ORDERED_DATA);
4809                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4810                 } else {
4811                         set_opt(sb, JOURNAL_DATA);
4812                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4813                 }
4814                 break;
4815
4816         case EXT4_MOUNT_ORDERED_DATA:
4817         case EXT4_MOUNT_WRITEBACK_DATA:
4818                 if (!jbd2_journal_check_available_features
4819                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4820                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4821                                "requested data journaling mode");
4822                         goto failed_mount_wq;
4823                 }
4824                 break;
4825         default:
4826                 break;
4827         }
4828
4829         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4830             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4831                 ext4_msg(sb, KERN_ERR, "can't mount with "
4832                         "journal_async_commit in data=ordered mode");
4833                 goto failed_mount_wq;
4834         }
4835
4836         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4837
4838         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4839         sbi->s_journal->j_submit_inode_data_buffers =
4840                 ext4_journal_submit_inode_data_buffers;
4841         sbi->s_journal->j_finish_inode_data_buffers =
4842                 ext4_journal_finish_inode_data_buffers;
4843
4844 no_journal:
4845         if (!test_opt(sb, NO_MBCACHE)) {
4846                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4847                 if (!sbi->s_ea_block_cache) {
4848                         ext4_msg(sb, KERN_ERR,
4849                                  "Failed to create ea_block_cache");
4850                         goto failed_mount_wq;
4851                 }
4852
4853                 if (ext4_has_feature_ea_inode(sb)) {
4854                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4855                         if (!sbi->s_ea_inode_cache) {
4856                                 ext4_msg(sb, KERN_ERR,
4857                                          "Failed to create ea_inode_cache");
4858                                 goto failed_mount_wq;
4859                         }
4860                 }
4861         }
4862
4863         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4864                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4865                 goto failed_mount_wq;
4866         }
4867
4868         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4869             !ext4_has_feature_encrypt(sb)) {
4870                 ext4_set_feature_encrypt(sb);
4871                 ext4_commit_super(sb, 1);
4872         }
4873
4874         /*
4875          * Get the # of file system overhead blocks from the
4876          * superblock if present.
4877          */
4878         if (es->s_overhead_clusters)
4879                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4880         else {
4881                 err = ext4_calculate_overhead(sb);
4882                 if (err)
4883                         goto failed_mount_wq;
4884         }
4885
4886         /*
4887          * The maximum number of concurrent works can be high and
4888          * concurrency isn't really necessary.  Limit it to 1.
4889          */
4890         EXT4_SB(sb)->rsv_conversion_wq =
4891                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4892         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4893                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4894                 ret = -ENOMEM;
4895                 goto failed_mount4;
4896         }
4897
4898         /*
4899          * The jbd2_journal_load will have done any necessary log recovery,
4900          * so we can safely mount the rest of the filesystem now.
4901          */
4902
4903         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4904         if (IS_ERR(root)) {
4905                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4906                 ret = PTR_ERR(root);
4907                 root = NULL;
4908                 goto failed_mount4;
4909         }
4910         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4911                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4912                 iput(root);
4913                 goto failed_mount4;
4914         }
4915
4916 #ifdef CONFIG_UNICODE
4917         if (sb->s_encoding)
4918                 sb->s_d_op = &ext4_dentry_ops;
4919 #endif
4920
4921         sb->s_root = d_make_root(root);
4922         if (!sb->s_root) {
4923                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4924                 ret = -ENOMEM;
4925                 goto failed_mount4;
4926         }
4927
4928         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4929         if (ret == -EROFS) {
4930                 sb->s_flags |= SB_RDONLY;
4931                 ret = 0;
4932         } else if (ret)
4933                 goto failed_mount4a;
4934
4935         ext4_set_resv_clusters(sb);
4936
4937         if (test_opt(sb, BLOCK_VALIDITY)) {
4938                 err = ext4_setup_system_zone(sb);
4939                 if (err) {
4940                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
4941                                  "zone (%d)", err);
4942                         goto failed_mount4a;
4943                 }
4944         }
4945         ext4_fc_replay_cleanup(sb);
4946
4947         ext4_ext_init(sb);
4948         err = ext4_mb_init(sb);
4949         if (err) {
4950                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4951                          err);
4952                 goto failed_mount5;
4953         }
4954
4955         block = ext4_count_free_clusters(sb);
4956         ext4_free_blocks_count_set(sbi->s_es,
4957                                    EXT4_C2B(sbi, block));
4958         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4959                                   GFP_KERNEL);
4960         if (!err) {
4961                 unsigned long freei = ext4_count_free_inodes(sb);
4962                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4963                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4964                                           GFP_KERNEL);
4965         }
4966         if (!err)
4967                 err = percpu_counter_init(&sbi->s_dirs_counter,
4968                                           ext4_count_dirs(sb), GFP_KERNEL);
4969         if (!err)
4970                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4971                                           GFP_KERNEL);
4972         if (!err)
4973                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
4974
4975         if (err) {
4976                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4977                 goto failed_mount6;
4978         }
4979
4980         if (ext4_has_feature_flex_bg(sb))
4981                 if (!ext4_fill_flex_info(sb)) {
4982                         ext4_msg(sb, KERN_ERR,
4983                                "unable to initialize "
4984                                "flex_bg meta info!");
4985                         goto failed_mount6;
4986                 }
4987
4988         err = ext4_register_li_request(sb, first_not_zeroed);
4989         if (err)
4990                 goto failed_mount6;
4991
4992         err = ext4_register_sysfs(sb);
4993         if (err)
4994                 goto failed_mount7;
4995
4996 #ifdef CONFIG_QUOTA
4997         /* Enable quota usage during mount. */
4998         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4999                 err = ext4_enable_quotas(sb);
5000                 if (err)
5001                         goto failed_mount8;
5002         }
5003 #endif  /* CONFIG_QUOTA */
5004
5005         /*
5006          * Save the original bdev mapping's wb_err value which could be
5007          * used to detect the metadata async write error.
5008          */
5009         spin_lock_init(&sbi->s_bdev_wb_lock);
5010         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5011                                  &sbi->s_bdev_wb_err);
5012         sb->s_bdev->bd_super = sb;
5013         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5014         ext4_orphan_cleanup(sb, es);
5015         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5016         if (needs_recovery) {
5017                 ext4_msg(sb, KERN_INFO, "recovery complete");
5018                 err = ext4_mark_recovery_complete(sb, es);
5019                 if (err)
5020                         goto failed_mount8;
5021         }
5022         if (EXT4_SB(sb)->s_journal) {
5023                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5024                         descr = " journalled data mode";
5025                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5026                         descr = " ordered data mode";
5027                 else
5028                         descr = " writeback data mode";
5029         } else
5030                 descr = "out journal";
5031
5032         if (test_opt(sb, DISCARD)) {
5033                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
5034                 if (!blk_queue_discard(q))
5035                         ext4_msg(sb, KERN_WARNING,
5036                                  "mounting with \"discard\" option, but "
5037                                  "the device does not support discard");
5038         }
5039
5040         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5041                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
5042                          "Opts: %.*s%s%s. Quota mode: %s.", descr,
5043                          (int) sizeof(sbi->s_es->s_mount_opts),
5044                          sbi->s_es->s_mount_opts,
5045                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data,
5046                          ext4_quota_mode(sb));
5047
5048         if (es->s_error_count)
5049                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5050
5051         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5052         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5053         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5054         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5055         atomic_set(&sbi->s_warning_count, 0);
5056         atomic_set(&sbi->s_msg_count, 0);
5057
5058         kfree(orig_data);
5059         return 0;
5060
5061 cantfind_ext4:
5062         if (!silent)
5063                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5064         goto failed_mount;
5065
5066 failed_mount8:
5067         ext4_unregister_sysfs(sb);
5068         kobject_put(&sbi->s_kobj);
5069 failed_mount7:
5070         ext4_unregister_li_request(sb);
5071 failed_mount6:
5072         ext4_mb_release(sb);
5073         rcu_read_lock();
5074         flex_groups = rcu_dereference(sbi->s_flex_groups);
5075         if (flex_groups) {
5076                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
5077                         kvfree(flex_groups[i]);
5078                 kvfree(flex_groups);
5079         }
5080         rcu_read_unlock();
5081         percpu_counter_destroy(&sbi->s_freeclusters_counter);
5082         percpu_counter_destroy(&sbi->s_freeinodes_counter);
5083         percpu_counter_destroy(&sbi->s_dirs_counter);
5084         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
5085         percpu_free_rwsem(&sbi->s_writepages_rwsem);
5086 failed_mount5:
5087         ext4_ext_release(sb);
5088         ext4_release_system_zone(sb);
5089 failed_mount4a:
5090         dput(sb->s_root);
5091         sb->s_root = NULL;
5092 failed_mount4:
5093         ext4_msg(sb, KERN_ERR, "mount failed");
5094         if (EXT4_SB(sb)->rsv_conversion_wq)
5095                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5096 failed_mount_wq:
5097         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5098         sbi->s_ea_inode_cache = NULL;
5099
5100         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5101         sbi->s_ea_block_cache = NULL;
5102
5103         if (sbi->s_journal) {
5104                 jbd2_journal_destroy(sbi->s_journal);
5105                 sbi->s_journal = NULL;
5106         }
5107 failed_mount3a:
5108         ext4_es_unregister_shrinker(sbi);
5109 failed_mount3:
5110         del_timer_sync(&sbi->s_err_report);
5111         if (sbi->s_mmp_tsk)
5112                 kthread_stop(sbi->s_mmp_tsk);
5113 failed_mount2:
5114         rcu_read_lock();
5115         group_desc = rcu_dereference(sbi->s_group_desc);
5116         for (i = 0; i < db_count; i++)
5117                 brelse(group_desc[i]);
5118         kvfree(group_desc);
5119         rcu_read_unlock();
5120 failed_mount:
5121         if (sbi->s_chksum_driver)
5122                 crypto_free_shash(sbi->s_chksum_driver);
5123
5124 #ifdef CONFIG_UNICODE
5125         utf8_unload(sb->s_encoding);
5126 #endif
5127
5128 #ifdef CONFIG_QUOTA
5129         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5130                 kfree(get_qf_name(sb, sbi, i));
5131 #endif
5132         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5133         ext4_blkdev_remove(sbi);
5134         brelse(bh);
5135 out_fail:
5136         sb->s_fs_info = NULL;
5137         kfree(sbi->s_blockgroup_lock);
5138 out_free_base:
5139         kfree(sbi);
5140         kfree(orig_data);
5141         fs_put_dax(dax_dev);
5142         return err ? err : ret;
5143 }
5144
5145 /*
5146  * Setup any per-fs journal parameters now.  We'll do this both on
5147  * initial mount, once the journal has been initialised but before we've
5148  * done any recovery; and again on any subsequent remount.
5149  */
5150 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5151 {
5152         struct ext4_sb_info *sbi = EXT4_SB(sb);
5153
5154         journal->j_commit_interval = sbi->s_commit_interval;
5155         journal->j_min_batch_time = sbi->s_min_batch_time;
5156         journal->j_max_batch_time = sbi->s_max_batch_time;
5157         ext4_fc_init(sb, journal);
5158
5159         write_lock(&journal->j_state_lock);
5160         if (test_opt(sb, BARRIER))
5161                 journal->j_flags |= JBD2_BARRIER;
5162         else
5163                 journal->j_flags &= ~JBD2_BARRIER;
5164         if (test_opt(sb, DATA_ERR_ABORT))
5165                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5166         else
5167                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5168         write_unlock(&journal->j_state_lock);
5169 }
5170
5171 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5172                                              unsigned int journal_inum)
5173 {
5174         struct inode *journal_inode;
5175
5176         /*
5177          * Test for the existence of a valid inode on disk.  Bad things
5178          * happen if we iget() an unused inode, as the subsequent iput()
5179          * will try to delete it.
5180          */
5181         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5182         if (IS_ERR(journal_inode)) {
5183                 ext4_msg(sb, KERN_ERR, "no journal found");
5184                 return NULL;
5185         }
5186         if (!journal_inode->i_nlink) {
5187                 make_bad_inode(journal_inode);
5188                 iput(journal_inode);
5189                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5190                 return NULL;
5191         }
5192
5193         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
5194                   journal_inode, journal_inode->i_size);
5195         if (!S_ISREG(journal_inode->i_mode)) {
5196                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5197                 iput(journal_inode);
5198                 return NULL;
5199         }
5200         return journal_inode;
5201 }
5202
5203 static journal_t *ext4_get_journal(struct super_block *sb,
5204                                    unsigned int journal_inum)
5205 {
5206         struct inode *journal_inode;
5207         journal_t *journal;
5208
5209         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5210                 return NULL;
5211
5212         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5213         if (!journal_inode)
5214                 return NULL;
5215
5216         journal = jbd2_journal_init_inode(journal_inode);
5217         if (!journal) {
5218                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5219                 iput(journal_inode);
5220                 return NULL;
5221         }
5222         journal->j_private = sb;
5223         ext4_init_journal_params(sb, journal);
5224         return journal;
5225 }
5226
5227 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5228                                        dev_t j_dev)
5229 {
5230         struct buffer_head *bh;
5231         journal_t *journal;
5232         ext4_fsblk_t start;
5233         ext4_fsblk_t len;
5234         int hblock, blocksize;
5235         ext4_fsblk_t sb_block;
5236         unsigned long offset;
5237         struct ext4_super_block *es;
5238         struct block_device *bdev;
5239
5240         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5241                 return NULL;
5242
5243         bdev = ext4_blkdev_get(j_dev, sb);
5244         if (bdev == NULL)
5245                 return NULL;
5246
5247         blocksize = sb->s_blocksize;
5248         hblock = bdev_logical_block_size(bdev);
5249         if (blocksize < hblock) {
5250                 ext4_msg(sb, KERN_ERR,
5251                         "blocksize too small for journal device");
5252                 goto out_bdev;
5253         }
5254
5255         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5256         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5257         set_blocksize(bdev, blocksize);
5258         if (!(bh = __bread(bdev, sb_block, blocksize))) {
5259                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5260                        "external journal");
5261                 goto out_bdev;
5262         }
5263
5264         es = (struct ext4_super_block *) (bh->b_data + offset);
5265         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5266             !(le32_to_cpu(es->s_feature_incompat) &
5267               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5268                 ext4_msg(sb, KERN_ERR, "external journal has "
5269                                         "bad superblock");
5270                 brelse(bh);
5271                 goto out_bdev;
5272         }
5273
5274         if ((le32_to_cpu(es->s_feature_ro_compat) &
5275              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5276             es->s_checksum != ext4_superblock_csum(sb, es)) {
5277                 ext4_msg(sb, KERN_ERR, "external journal has "
5278                                        "corrupt superblock");
5279                 brelse(bh);
5280                 goto out_bdev;
5281         }
5282
5283         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5284                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5285                 brelse(bh);
5286                 goto out_bdev;
5287         }
5288
5289         len = ext4_blocks_count(es);
5290         start = sb_block + 1;
5291         brelse(bh);     /* we're done with the superblock */
5292
5293         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5294                                         start, len, blocksize);
5295         if (!journal) {
5296                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5297                 goto out_bdev;
5298         }
5299         journal->j_private = sb;
5300         if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
5301                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5302                 goto out_journal;
5303         }
5304         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5305                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5306                                         "user (unsupported) - %d",
5307                         be32_to_cpu(journal->j_superblock->s_nr_users));
5308                 goto out_journal;
5309         }
5310         EXT4_SB(sb)->s_journal_bdev = bdev;
5311         ext4_init_journal_params(sb, journal);
5312         return journal;
5313
5314 out_journal:
5315         jbd2_journal_destroy(journal);
5316 out_bdev:
5317         ext4_blkdev_put(bdev);
5318         return NULL;
5319 }
5320
5321 static int ext4_load_journal(struct super_block *sb,
5322                              struct ext4_super_block *es,
5323                              unsigned long journal_devnum)
5324 {
5325         journal_t *journal;
5326         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5327         dev_t journal_dev;
5328         int err = 0;
5329         int really_read_only;
5330         int journal_dev_ro;
5331
5332         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5333                 return -EFSCORRUPTED;
5334
5335         if (journal_devnum &&
5336             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5337                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5338                         "numbers have changed");
5339                 journal_dev = new_decode_dev(journal_devnum);
5340         } else
5341                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5342
5343         if (journal_inum && journal_dev) {
5344                 ext4_msg(sb, KERN_ERR,
5345                          "filesystem has both journal inode and journal device!");
5346                 return -EINVAL;
5347         }
5348
5349         if (journal_inum) {
5350                 journal = ext4_get_journal(sb, journal_inum);
5351                 if (!journal)
5352                         return -EINVAL;
5353         } else {
5354                 journal = ext4_get_dev_journal(sb, journal_dev);
5355                 if (!journal)
5356                         return -EINVAL;
5357         }
5358
5359         journal_dev_ro = bdev_read_only(journal->j_dev);
5360         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5361
5362         if (journal_dev_ro && !sb_rdonly(sb)) {
5363                 ext4_msg(sb, KERN_ERR,
5364                          "journal device read-only, try mounting with '-o ro'");
5365                 err = -EROFS;
5366                 goto err_out;
5367         }
5368
5369         /*
5370          * Are we loading a blank journal or performing recovery after a
5371          * crash?  For recovery, we need to check in advance whether we
5372          * can get read-write access to the device.
5373          */
5374         if (ext4_has_feature_journal_needs_recovery(sb)) {
5375                 if (sb_rdonly(sb)) {
5376                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5377                                         "required on readonly filesystem");
5378                         if (really_read_only) {
5379                                 ext4_msg(sb, KERN_ERR, "write access "
5380                                         "unavailable, cannot proceed "
5381                                         "(try mounting with noload)");
5382                                 err = -EROFS;
5383                                 goto err_out;
5384                         }
5385                         ext4_msg(sb, KERN_INFO, "write access will "
5386                                "be enabled during recovery");
5387                 }
5388         }
5389
5390         if (!(journal->j_flags & JBD2_BARRIER))
5391                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5392
5393         if (!ext4_has_feature_journal_needs_recovery(sb))
5394                 err = jbd2_journal_wipe(journal, !really_read_only);
5395         if (!err) {
5396                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5397                 if (save)
5398                         memcpy(save, ((char *) es) +
5399                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5400                 err = jbd2_journal_load(journal);
5401                 if (save)
5402                         memcpy(((char *) es) + EXT4_S_ERR_START,
5403                                save, EXT4_S_ERR_LEN);
5404                 kfree(save);
5405         }
5406
5407         if (err) {
5408                 ext4_msg(sb, KERN_ERR, "error loading journal");
5409                 goto err_out;
5410         }
5411
5412         EXT4_SB(sb)->s_journal = journal;
5413         err = ext4_clear_journal_err(sb, es);
5414         if (err) {
5415                 EXT4_SB(sb)->s_journal = NULL;
5416                 jbd2_journal_destroy(journal);
5417                 return err;
5418         }
5419
5420         if (!really_read_only && journal_devnum &&
5421             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5422                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5423
5424                 /* Make sure we flush the recovery flag to disk. */
5425                 ext4_commit_super(sb, 1);
5426         }
5427
5428         return 0;
5429
5430 err_out:
5431         jbd2_journal_destroy(journal);
5432         return err;
5433 }
5434
5435 static int ext4_commit_super(struct super_block *sb, int sync)
5436 {
5437         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
5438         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5439         int error = 0;
5440
5441         if (!sbh || block_device_ejected(sb))
5442                 return error;
5443
5444         /*
5445          * If the file system is mounted read-only, don't update the
5446          * superblock write time.  This avoids updating the superblock
5447          * write time when we are mounting the root file system
5448          * read/only but we need to replay the journal; at that point,
5449          * for people who are east of GMT and who make their clock
5450          * tick in localtime for Windows bug-for-bug compatibility,
5451          * the clock is set in the future, and this will cause e2fsck
5452          * to complain and force a full file system check.
5453          */
5454         if (!(sb->s_flags & SB_RDONLY))
5455                 ext4_update_tstamp(es, s_wtime);
5456         if (sb->s_bdev->bd_part)
5457                 es->s_kbytes_written =
5458                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5459                             ((part_stat_read(sb->s_bdev->bd_part,
5460                                              sectors[STAT_WRITE]) -
5461                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
5462         else
5463                 es->s_kbytes_written =
5464                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5465         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5466                 ext4_free_blocks_count_set(es,
5467                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5468                                 &EXT4_SB(sb)->s_freeclusters_counter)));
5469         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5470                 es->s_free_inodes_count =
5471                         cpu_to_le32(percpu_counter_sum_positive(
5472                                 &EXT4_SB(sb)->s_freeinodes_counter));
5473         BUFFER_TRACE(sbh, "marking dirty");
5474         ext4_superblock_csum_set(sb);
5475         if (sync)
5476                 lock_buffer(sbh);
5477         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5478                 /*
5479                  * Oh, dear.  A previous attempt to write the
5480                  * superblock failed.  This could happen because the
5481                  * USB device was yanked out.  Or it could happen to
5482                  * be a transient write error and maybe the block will
5483                  * be remapped.  Nothing we can do but to retry the
5484                  * write and hope for the best.
5485                  */
5486                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5487                        "superblock detected");
5488                 clear_buffer_write_io_error(sbh);
5489                 set_buffer_uptodate(sbh);
5490         }
5491         mark_buffer_dirty(sbh);
5492         if (sync) {
5493                 unlock_buffer(sbh);
5494                 error = __sync_dirty_buffer(sbh,
5495                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5496                 if (buffer_write_io_error(sbh)) {
5497                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5498                                "superblock");
5499                         clear_buffer_write_io_error(sbh);
5500                         set_buffer_uptodate(sbh);
5501                 }
5502         }
5503         return error;
5504 }
5505
5506 /*
5507  * Have we just finished recovery?  If so, and if we are mounting (or
5508  * remounting) the filesystem readonly, then we will end up with a
5509  * consistent fs on disk.  Record that fact.
5510  */
5511 static int ext4_mark_recovery_complete(struct super_block *sb,
5512                                        struct ext4_super_block *es)
5513 {
5514         int err;
5515         journal_t *journal = EXT4_SB(sb)->s_journal;
5516
5517         if (!ext4_has_feature_journal(sb)) {
5518                 if (journal != NULL) {
5519                         ext4_error(sb, "Journal got removed while the fs was "
5520                                    "mounted!");
5521                         return -EFSCORRUPTED;
5522                 }
5523                 return 0;
5524         }
5525         jbd2_journal_lock_updates(journal);
5526         err = jbd2_journal_flush(journal);
5527         if (err < 0)
5528                 goto out;
5529
5530         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5531                 ext4_clear_feature_journal_needs_recovery(sb);
5532                 ext4_commit_super(sb, 1);
5533         }
5534 out:
5535         jbd2_journal_unlock_updates(journal);
5536         return err;
5537 }
5538
5539 /*
5540  * If we are mounting (or read-write remounting) a filesystem whose journal
5541  * has recorded an error from a previous lifetime, move that error to the
5542  * main filesystem now.
5543  */
5544 static int ext4_clear_journal_err(struct super_block *sb,
5545                                    struct ext4_super_block *es)
5546 {
5547         journal_t *journal;
5548         int j_errno;
5549         const char *errstr;
5550
5551         if (!ext4_has_feature_journal(sb)) {
5552                 ext4_error(sb, "Journal got removed while the fs was mounted!");
5553                 return -EFSCORRUPTED;
5554         }
5555
5556         journal = EXT4_SB(sb)->s_journal;
5557
5558         /*
5559          * Now check for any error status which may have been recorded in the
5560          * journal by a prior ext4_error() or ext4_abort()
5561          */
5562
5563         j_errno = jbd2_journal_errno(journal);
5564         if (j_errno) {
5565                 char nbuf[16];
5566
5567                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5568                 ext4_warning(sb, "Filesystem error recorded "
5569                              "from previous mount: %s", errstr);
5570                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5571
5572                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5573                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5574                 ext4_commit_super(sb, 1);
5575
5576                 jbd2_journal_clear_err(journal);
5577                 jbd2_journal_update_sb_errno(journal);
5578         }
5579         return 0;
5580 }
5581
5582 /*
5583  * Force the running and committing transactions to commit,
5584  * and wait on the commit.
5585  */
5586 int ext4_force_commit(struct super_block *sb)
5587 {
5588         journal_t *journal;
5589
5590         if (sb_rdonly(sb))
5591                 return 0;
5592
5593         journal = EXT4_SB(sb)->s_journal;
5594         return ext4_journal_force_commit(journal);
5595 }
5596
5597 static int ext4_sync_fs(struct super_block *sb, int wait)
5598 {
5599         int ret = 0;
5600         tid_t target;
5601         bool needs_barrier = false;
5602         struct ext4_sb_info *sbi = EXT4_SB(sb);
5603
5604         if (unlikely(ext4_forced_shutdown(sbi)))
5605                 return 0;
5606
5607         trace_ext4_sync_fs(sb, wait);
5608         flush_workqueue(sbi->rsv_conversion_wq);
5609         /*
5610          * Writeback quota in non-journalled quota case - journalled quota has
5611          * no dirty dquots
5612          */
5613         dquot_writeback_dquots(sb, -1);
5614         /*
5615          * Data writeback is possible w/o journal transaction, so barrier must
5616          * being sent at the end of the function. But we can skip it if
5617          * transaction_commit will do it for us.
5618          */
5619         if (sbi->s_journal) {
5620                 target = jbd2_get_latest_transaction(sbi->s_journal);
5621                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5622                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5623                         needs_barrier = true;
5624
5625                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5626                         if (wait)
5627                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5628                                                            target);
5629                 }
5630         } else if (wait && test_opt(sb, BARRIER))
5631                 needs_barrier = true;
5632         if (needs_barrier) {
5633                 int err;
5634                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL);
5635                 if (!ret)
5636                         ret = err;
5637         }
5638
5639         return ret;
5640 }
5641
5642 /*
5643  * LVM calls this function before a (read-only) snapshot is created.  This
5644  * gives us a chance to flush the journal completely and mark the fs clean.
5645  *
5646  * Note that only this function cannot bring a filesystem to be in a clean
5647  * state independently. It relies on upper layer to stop all data & metadata
5648  * modifications.
5649  */
5650 static int ext4_freeze(struct super_block *sb)
5651 {
5652         int error = 0;
5653         journal_t *journal;
5654
5655         if (sb_rdonly(sb))
5656                 return 0;
5657
5658         journal = EXT4_SB(sb)->s_journal;
5659
5660         if (journal) {
5661                 /* Now we set up the journal barrier. */
5662                 jbd2_journal_lock_updates(journal);
5663
5664                 /*
5665                  * Don't clear the needs_recovery flag if we failed to
5666                  * flush the journal.
5667                  */
5668                 error = jbd2_journal_flush(journal);
5669                 if (error < 0)
5670                         goto out;
5671
5672                 /* Journal blocked and flushed, clear needs_recovery flag. */
5673                 ext4_clear_feature_journal_needs_recovery(sb);
5674         }
5675
5676         error = ext4_commit_super(sb, 1);
5677 out:
5678         if (journal)
5679                 /* we rely on upper layer to stop further updates */
5680                 jbd2_journal_unlock_updates(journal);
5681         return error;
5682 }
5683
5684 /*
5685  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5686  * flag here, even though the filesystem is not technically dirty yet.
5687  */
5688 static int ext4_unfreeze(struct super_block *sb)
5689 {
5690         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5691                 return 0;
5692
5693         if (EXT4_SB(sb)->s_journal) {
5694                 /* Reset the needs_recovery flag before the fs is unlocked. */
5695                 ext4_set_feature_journal_needs_recovery(sb);
5696         }
5697
5698         ext4_commit_super(sb, 1);
5699         return 0;
5700 }
5701
5702 /*
5703  * Structure to save mount options for ext4_remount's benefit
5704  */
5705 struct ext4_mount_options {
5706         unsigned long s_mount_opt;
5707         unsigned long s_mount_opt2;
5708         kuid_t s_resuid;
5709         kgid_t s_resgid;
5710         unsigned long s_commit_interval;
5711         u32 s_min_batch_time, s_max_batch_time;
5712 #ifdef CONFIG_QUOTA
5713         int s_jquota_fmt;
5714         char *s_qf_names[EXT4_MAXQUOTAS];
5715 #endif
5716 };
5717
5718 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5719 {
5720         struct ext4_super_block *es;
5721         struct ext4_sb_info *sbi = EXT4_SB(sb);
5722         unsigned long old_sb_flags, vfs_flags;
5723         struct ext4_mount_options old_opts;
5724         int enable_quota = 0;
5725         ext4_group_t g;
5726         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5727         int err = 0;
5728 #ifdef CONFIG_QUOTA
5729         int i, j;
5730         char *to_free[EXT4_MAXQUOTAS];
5731 #endif
5732         char *orig_data = kstrdup(data, GFP_KERNEL);
5733
5734         if (data && !orig_data)
5735                 return -ENOMEM;
5736
5737         /* Store the original options */
5738         old_sb_flags = sb->s_flags;
5739         old_opts.s_mount_opt = sbi->s_mount_opt;
5740         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5741         old_opts.s_resuid = sbi->s_resuid;
5742         old_opts.s_resgid = sbi->s_resgid;
5743         old_opts.s_commit_interval = sbi->s_commit_interval;
5744         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5745         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5746 #ifdef CONFIG_QUOTA
5747         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5748         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5749                 if (sbi->s_qf_names[i]) {
5750                         char *qf_name = get_qf_name(sb, sbi, i);
5751
5752                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5753                         if (!old_opts.s_qf_names[i]) {
5754                                 for (j = 0; j < i; j++)
5755                                         kfree(old_opts.s_qf_names[j]);
5756                                 kfree(orig_data);
5757                                 return -ENOMEM;
5758                         }
5759                 } else
5760                         old_opts.s_qf_names[i] = NULL;
5761 #endif
5762         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5763                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5764
5765         /*
5766          * Some options can be enabled by ext4 and/or by VFS mount flag
5767          * either way we need to make sure it matches in both *flags and
5768          * s_flags. Copy those selected flags from *flags to s_flags
5769          */
5770         vfs_flags = SB_LAZYTIME | SB_I_VERSION;
5771         sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags);
5772
5773         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5774                 err = -EINVAL;
5775                 goto restore_opts;
5776         }
5777
5778         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5779             test_opt(sb, JOURNAL_CHECKSUM)) {
5780                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5781                          "during remount not supported; ignoring");
5782                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5783         }
5784
5785         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5786                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5787                         ext4_msg(sb, KERN_ERR, "can't mount with "
5788                                  "both data=journal and delalloc");
5789                         err = -EINVAL;
5790                         goto restore_opts;
5791                 }
5792                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5793                         ext4_msg(sb, KERN_ERR, "can't mount with "
5794                                  "both data=journal and dioread_nolock");
5795                         err = -EINVAL;
5796                         goto restore_opts;
5797                 }
5798         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5799                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5800                         ext4_msg(sb, KERN_ERR, "can't mount with "
5801                                 "journal_async_commit in data=ordered mode");
5802                         err = -EINVAL;
5803                         goto restore_opts;
5804                 }
5805         }
5806
5807         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5808                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5809                 err = -EINVAL;
5810                 goto restore_opts;
5811         }
5812
5813         if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED))
5814                 ext4_abort(sb, EXT4_ERR_ESHUTDOWN, "Abort forced by user");
5815
5816         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5817                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5818
5819         es = sbi->s_es;
5820
5821         if (sbi->s_journal) {
5822                 ext4_init_journal_params(sb, sbi->s_journal);
5823                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5824         }
5825
5826         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5827                 if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED)) {
5828                         err = -EROFS;
5829                         goto restore_opts;
5830                 }
5831
5832                 if (*flags & SB_RDONLY) {
5833                         err = sync_filesystem(sb);
5834                         if (err < 0)
5835                                 goto restore_opts;
5836                         err = dquot_suspend(sb, -1);
5837                         if (err < 0)
5838                                 goto restore_opts;
5839
5840                         /*
5841                          * First of all, the unconditional stuff we have to do
5842                          * to disable replay of the journal when we next remount
5843                          */
5844                         sb->s_flags |= SB_RDONLY;
5845
5846                         /*
5847                          * OK, test if we are remounting a valid rw partition
5848                          * readonly, and if so set the rdonly flag and then
5849                          * mark the partition as valid again.
5850                          */
5851                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5852                             (sbi->s_mount_state & EXT4_VALID_FS))
5853                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5854
5855                         if (sbi->s_journal) {
5856                                 /*
5857                                  * We let remount-ro finish even if marking fs
5858                                  * as clean failed...
5859                                  */
5860                                 ext4_mark_recovery_complete(sb, es);
5861                         }
5862                         if (sbi->s_mmp_tsk)
5863                                 kthread_stop(sbi->s_mmp_tsk);
5864                 } else {
5865                         /* Make sure we can mount this feature set readwrite */
5866                         if (ext4_has_feature_readonly(sb) ||
5867                             !ext4_feature_set_ok(sb, 0)) {
5868                                 err = -EROFS;
5869                                 goto restore_opts;
5870                         }
5871                         /*
5872                          * Make sure the group descriptor checksums
5873                          * are sane.  If they aren't, refuse to remount r/w.
5874                          */
5875                         for (g = 0; g < sbi->s_groups_count; g++) {
5876                                 struct ext4_group_desc *gdp =
5877                                         ext4_get_group_desc(sb, g, NULL);
5878
5879                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5880                                         ext4_msg(sb, KERN_ERR,
5881                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5882                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5883                                                le16_to_cpu(gdp->bg_checksum));
5884                                         err = -EFSBADCRC;
5885                                         goto restore_opts;
5886                                 }
5887                         }
5888
5889                         /*
5890                          * If we have an unprocessed orphan list hanging
5891                          * around from a previously readonly bdev mount,
5892                          * require a full umount/remount for now.
5893                          */
5894                         if (es->s_last_orphan) {
5895                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5896                                        "remount RDWR because of unprocessed "
5897                                        "orphan inode list.  Please "
5898                                        "umount/remount instead");
5899                                 err = -EINVAL;
5900                                 goto restore_opts;
5901                         }
5902
5903                         /*
5904                          * Mounting a RDONLY partition read-write, so reread
5905                          * and store the current valid flag.  (It may have
5906                          * been changed by e2fsck since we originally mounted
5907                          * the partition.)
5908                          */
5909                         if (sbi->s_journal) {
5910                                 err = ext4_clear_journal_err(sb, es);
5911                                 if (err)
5912                                         goto restore_opts;
5913                         }
5914                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5915
5916                         err = ext4_setup_super(sb, es, 0);
5917                         if (err)
5918                                 goto restore_opts;
5919
5920                         sb->s_flags &= ~SB_RDONLY;
5921                         if (ext4_has_feature_mmp(sb))
5922                                 if (ext4_multi_mount_protect(sb,
5923                                                 le64_to_cpu(es->s_mmp_block))) {
5924                                         err = -EROFS;
5925                                         goto restore_opts;
5926                                 }
5927                         enable_quota = 1;
5928                 }
5929         }
5930
5931         /*
5932          * Reinitialize lazy itable initialization thread based on
5933          * current settings
5934          */
5935         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5936                 ext4_unregister_li_request(sb);
5937         else {
5938                 ext4_group_t first_not_zeroed;
5939                 first_not_zeroed = ext4_has_uninit_itable(sb);
5940                 ext4_register_li_request(sb, first_not_zeroed);
5941         }
5942
5943         /*
5944          * Handle creation of system zone data early because it can fail.
5945          * Releasing of existing data is done when we are sure remount will
5946          * succeed.
5947          */
5948         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
5949                 err = ext4_setup_system_zone(sb);
5950                 if (err)
5951                         goto restore_opts;
5952         }
5953
5954         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5955                 err = ext4_commit_super(sb, 1);
5956                 if (err)
5957                         goto restore_opts;
5958         }
5959
5960 #ifdef CONFIG_QUOTA
5961         /* Release old quota file names */
5962         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5963                 kfree(old_opts.s_qf_names[i]);
5964         if (enable_quota) {
5965                 if (sb_any_quota_suspended(sb))
5966                         dquot_resume(sb, -1);
5967                 else if (ext4_has_feature_quota(sb)) {
5968                         err = ext4_enable_quotas(sb);
5969                         if (err)
5970                                 goto restore_opts;
5971                 }
5972         }
5973 #endif
5974         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
5975                 ext4_release_system_zone(sb);
5976
5977         /*
5978          * Some options can be enabled by ext4 and/or by VFS mount flag
5979          * either way we need to make sure it matches in both *flags and
5980          * s_flags. Copy those selected flags from s_flags to *flags
5981          */
5982         *flags = (*flags & ~vfs_flags) | (sb->s_flags & vfs_flags);
5983
5984         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s. Quota mode: %s.",
5985                  orig_data, ext4_quota_mode(sb));
5986         kfree(orig_data);
5987         return 0;
5988
5989 restore_opts:
5990         sb->s_flags = old_sb_flags;
5991         sbi->s_mount_opt = old_opts.s_mount_opt;
5992         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5993         sbi->s_resuid = old_opts.s_resuid;
5994         sbi->s_resgid = old_opts.s_resgid;
5995         sbi->s_commit_interval = old_opts.s_commit_interval;
5996         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5997         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5998         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
5999                 ext4_release_system_zone(sb);
6000 #ifdef CONFIG_QUOTA
6001         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6002         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6003                 to_free[i] = get_qf_name(sb, sbi, i);
6004                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6005         }
6006         synchronize_rcu();
6007         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6008                 kfree(to_free[i]);
6009 #endif
6010         kfree(orig_data);
6011         return err;
6012 }
6013
6014 #ifdef CONFIG_QUOTA
6015 static int ext4_statfs_project(struct super_block *sb,
6016                                kprojid_t projid, struct kstatfs *buf)
6017 {
6018         struct kqid qid;
6019         struct dquot *dquot;
6020         u64 limit;
6021         u64 curblock;
6022
6023         qid = make_kqid_projid(projid);
6024         dquot = dqget(sb, qid);
6025         if (IS_ERR(dquot))
6026                 return PTR_ERR(dquot);
6027         spin_lock(&dquot->dq_dqb_lock);
6028
6029         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6030                              dquot->dq_dqb.dqb_bhardlimit);
6031         limit >>= sb->s_blocksize_bits;
6032
6033         if (limit && buf->f_blocks > limit) {
6034                 curblock = (dquot->dq_dqb.dqb_curspace +
6035                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6036                 buf->f_blocks = limit;
6037                 buf->f_bfree = buf->f_bavail =
6038                         (buf->f_blocks > curblock) ?
6039                          (buf->f_blocks - curblock) : 0;
6040         }
6041
6042         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6043                              dquot->dq_dqb.dqb_ihardlimit);
6044         if (limit && buf->f_files > limit) {
6045                 buf->f_files = limit;
6046                 buf->f_ffree =
6047                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6048                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6049         }
6050
6051         spin_unlock(&dquot->dq_dqb_lock);
6052         dqput(dquot);
6053         return 0;
6054 }
6055 #endif
6056
6057 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6058 {
6059         struct super_block *sb = dentry->d_sb;
6060         struct ext4_sb_info *sbi = EXT4_SB(sb);
6061         struct ext4_super_block *es = sbi->s_es;
6062         ext4_fsblk_t overhead = 0, resv_blocks;
6063         u64 fsid;
6064         s64 bfree;
6065         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6066
6067         if (!test_opt(sb, MINIX_DF))
6068                 overhead = sbi->s_overhead;
6069
6070         buf->f_type = EXT4_SUPER_MAGIC;
6071         buf->f_bsize = sb->s_blocksize;
6072         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6073         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6074                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6075         /* prevent underflow in case that few free space is available */
6076         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6077         buf->f_bavail = buf->f_bfree -
6078                         (ext4_r_blocks_count(es) + resv_blocks);
6079         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6080                 buf->f_bavail = 0;
6081         buf->f_files = le32_to_cpu(es->s_inodes_count);
6082         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6083         buf->f_namelen = EXT4_NAME_LEN;
6084         fsid = le64_to_cpup((void *)es->s_uuid) ^
6085                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
6086         buf->f_fsid = u64_to_fsid(fsid);
6087
6088 #ifdef CONFIG_QUOTA
6089         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6090             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6091                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6092 #endif
6093         return 0;
6094 }
6095
6096
6097 #ifdef CONFIG_QUOTA
6098
6099 /*
6100  * Helper functions so that transaction is started before we acquire dqio_sem
6101  * to keep correct lock ordering of transaction > dqio_sem
6102  */
6103 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6104 {
6105         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6106 }
6107
6108 static int ext4_write_dquot(struct dquot *dquot)
6109 {
6110         int ret, err;
6111         handle_t *handle;
6112         struct inode *inode;
6113
6114         inode = dquot_to_inode(dquot);
6115         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6116                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6117         if (IS_ERR(handle))
6118                 return PTR_ERR(handle);
6119         ret = dquot_commit(dquot);
6120         err = ext4_journal_stop(handle);
6121         if (!ret)
6122                 ret = err;
6123         return ret;
6124 }
6125
6126 static int ext4_acquire_dquot(struct dquot *dquot)
6127 {
6128         int ret, err;
6129         handle_t *handle;
6130
6131         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6132                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6133         if (IS_ERR(handle))
6134                 return PTR_ERR(handle);
6135         ret = dquot_acquire(dquot);
6136         err = ext4_journal_stop(handle);
6137         if (!ret)
6138                 ret = err;
6139         return ret;
6140 }
6141
6142 static int ext4_release_dquot(struct dquot *dquot)
6143 {
6144         int ret, err;
6145         handle_t *handle;
6146
6147         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6148                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6149         if (IS_ERR(handle)) {
6150                 /* Release dquot anyway to avoid endless cycle in dqput() */
6151                 dquot_release(dquot);
6152                 return PTR_ERR(handle);
6153         }
6154         ret = dquot_release(dquot);
6155         err = ext4_journal_stop(handle);
6156         if (!ret)
6157                 ret = err;
6158         return ret;
6159 }
6160
6161 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6162 {
6163         struct super_block *sb = dquot->dq_sb;
6164
6165         if (ext4_is_quota_journalled(sb)) {
6166                 dquot_mark_dquot_dirty(dquot);
6167                 return ext4_write_dquot(dquot);
6168         } else {
6169                 return dquot_mark_dquot_dirty(dquot);
6170         }
6171 }
6172
6173 static int ext4_write_info(struct super_block *sb, int type)
6174 {
6175         int ret, err;
6176         handle_t *handle;
6177
6178         /* Data block + inode block */
6179         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
6180         if (IS_ERR(handle))
6181                 return PTR_ERR(handle);
6182         ret = dquot_commit_info(sb, type);
6183         err = ext4_journal_stop(handle);
6184         if (!ret)
6185                 ret = err;
6186         return ret;
6187 }
6188
6189 /*
6190  * Turn on quotas during mount time - we need to find
6191  * the quota file and such...
6192  */
6193 static int ext4_quota_on_mount(struct super_block *sb, int type)
6194 {
6195         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
6196                                         EXT4_SB(sb)->s_jquota_fmt, type);
6197 }
6198
6199 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6200 {
6201         struct ext4_inode_info *ei = EXT4_I(inode);
6202
6203         /* The first argument of lockdep_set_subclass has to be
6204          * *exactly* the same as the argument to init_rwsem() --- in
6205          * this case, in init_once() --- or lockdep gets unhappy
6206          * because the name of the lock is set using the
6207          * stringification of the argument to init_rwsem().
6208          */
6209         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6210         lockdep_set_subclass(&ei->i_data_sem, subclass);
6211 }
6212
6213 /*
6214  * Standard function to be called on quota_on
6215  */
6216 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6217                          const struct path *path)
6218 {
6219         int err;
6220
6221         if (!test_opt(sb, QUOTA))
6222                 return -EINVAL;
6223
6224         /* Quotafile not on the same filesystem? */
6225         if (path->dentry->d_sb != sb)
6226                 return -EXDEV;
6227
6228         /* Quota already enabled for this file? */
6229         if (IS_NOQUOTA(d_inode(path->dentry)))
6230                 return -EBUSY;
6231
6232         /* Journaling quota? */
6233         if (EXT4_SB(sb)->s_qf_names[type]) {
6234                 /* Quotafile not in fs root? */
6235                 if (path->dentry->d_parent != sb->s_root)
6236                         ext4_msg(sb, KERN_WARNING,
6237                                 "Quota file not on filesystem root. "
6238                                 "Journaled quota will not work");
6239                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6240         } else {
6241                 /*
6242                  * Clear the flag just in case mount options changed since
6243                  * last time.
6244                  */
6245                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6246         }
6247
6248         /*
6249          * When we journal data on quota file, we have to flush journal to see
6250          * all updates to the file when we bypass pagecache...
6251          */
6252         if (EXT4_SB(sb)->s_journal &&
6253             ext4_should_journal_data(d_inode(path->dentry))) {
6254                 /*
6255                  * We don't need to lock updates but journal_flush() could
6256                  * otherwise be livelocked...
6257                  */
6258                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6259                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
6260                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6261                 if (err)
6262                         return err;
6263         }
6264
6265         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6266         err = dquot_quota_on(sb, type, format_id, path);
6267         if (err) {
6268                 lockdep_set_quota_inode(path->dentry->d_inode,
6269                                              I_DATA_SEM_NORMAL);
6270         } else {
6271                 struct inode *inode = d_inode(path->dentry);
6272                 handle_t *handle;
6273
6274                 /*
6275                  * Set inode flags to prevent userspace from messing with quota
6276                  * files. If this fails, we return success anyway since quotas
6277                  * are already enabled and this is not a hard failure.
6278                  */
6279                 inode_lock(inode);
6280                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6281                 if (IS_ERR(handle))
6282                         goto unlock_inode;
6283                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6284                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6285                                 S_NOATIME | S_IMMUTABLE);
6286                 err = ext4_mark_inode_dirty(handle, inode);
6287                 ext4_journal_stop(handle);
6288         unlock_inode:
6289                 inode_unlock(inode);
6290         }
6291         return err;
6292 }
6293
6294 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6295                              unsigned int flags)
6296 {
6297         int err;
6298         struct inode *qf_inode;
6299         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6300                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6301                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6302                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6303         };
6304
6305         BUG_ON(!ext4_has_feature_quota(sb));
6306
6307         if (!qf_inums[type])
6308                 return -EPERM;
6309
6310         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6311         if (IS_ERR(qf_inode)) {
6312                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6313                 return PTR_ERR(qf_inode);
6314         }
6315
6316         /* Don't account quota for quota files to avoid recursion */
6317         qf_inode->i_flags |= S_NOQUOTA;
6318         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6319         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6320         if (err)
6321                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6322         iput(qf_inode);
6323
6324         return err;
6325 }
6326
6327 /* Enable usage tracking for all quota types. */
6328 static int ext4_enable_quotas(struct super_block *sb)
6329 {
6330         int type, err = 0;
6331         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6332                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6333                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6334                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6335         };
6336         bool quota_mopt[EXT4_MAXQUOTAS] = {
6337                 test_opt(sb, USRQUOTA),
6338                 test_opt(sb, GRPQUOTA),
6339                 test_opt(sb, PRJQUOTA),
6340         };
6341
6342         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6343         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6344                 if (qf_inums[type]) {
6345                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6346                                 DQUOT_USAGE_ENABLED |
6347                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6348                         if (err) {
6349                                 ext4_warning(sb,
6350                                         "Failed to enable quota tracking "
6351                                         "(type=%d, err=%d). Please run "
6352                                         "e2fsck to fix.", type, err);
6353                                 for (type--; type >= 0; type--)
6354                                         dquot_quota_off(sb, type);
6355
6356                                 return err;
6357                         }
6358                 }
6359         }
6360         return 0;
6361 }
6362
6363 static int ext4_quota_off(struct super_block *sb, int type)
6364 {
6365         struct inode *inode = sb_dqopt(sb)->files[type];
6366         handle_t *handle;
6367         int err;
6368
6369         /* Force all delayed allocation blocks to be allocated.
6370          * Caller already holds s_umount sem */
6371         if (test_opt(sb, DELALLOC))
6372                 sync_filesystem(sb);
6373
6374         if (!inode || !igrab(inode))
6375                 goto out;
6376
6377         err = dquot_quota_off(sb, type);
6378         if (err || ext4_has_feature_quota(sb))
6379                 goto out_put;
6380
6381         inode_lock(inode);
6382         /*
6383          * Update modification times of quota files when userspace can
6384          * start looking at them. If we fail, we return success anyway since
6385          * this is not a hard failure and quotas are already disabled.
6386          */
6387         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6388         if (IS_ERR(handle)) {
6389                 err = PTR_ERR(handle);
6390                 goto out_unlock;
6391         }
6392         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6393         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6394         inode->i_mtime = inode->i_ctime = current_time(inode);
6395         err = ext4_mark_inode_dirty(handle, inode);
6396         ext4_journal_stop(handle);
6397 out_unlock:
6398         inode_unlock(inode);
6399 out_put:
6400         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6401         iput(inode);
6402         return err;
6403 out:
6404         return dquot_quota_off(sb, type);
6405 }
6406
6407 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6408  * acquiring the locks... As quota files are never truncated and quota code
6409  * itself serializes the operations (and no one else should touch the files)
6410  * we don't have to be afraid of races */
6411 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6412                                size_t len, loff_t off)
6413 {
6414         struct inode *inode = sb_dqopt(sb)->files[type];
6415         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6416         int offset = off & (sb->s_blocksize - 1);
6417         int tocopy;
6418         size_t toread;
6419         struct buffer_head *bh;
6420         loff_t i_size = i_size_read(inode);
6421
6422         if (off > i_size)
6423                 return 0;
6424         if (off+len > i_size)
6425                 len = i_size-off;
6426         toread = len;
6427         while (toread > 0) {
6428                 tocopy = sb->s_blocksize - offset < toread ?
6429                                 sb->s_blocksize - offset : toread;
6430                 bh = ext4_bread(NULL, inode, blk, 0);
6431                 if (IS_ERR(bh))
6432                         return PTR_ERR(bh);
6433                 if (!bh)        /* A hole? */
6434                         memset(data, 0, tocopy);
6435                 else
6436                         memcpy(data, bh->b_data+offset, tocopy);
6437                 brelse(bh);
6438                 offset = 0;
6439                 toread -= tocopy;
6440                 data += tocopy;
6441                 blk++;
6442         }
6443         return len;
6444 }
6445
6446 /* Write to quotafile (we know the transaction is already started and has
6447  * enough credits) */
6448 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6449                                 const char *data, size_t len, loff_t off)
6450 {
6451         struct inode *inode = sb_dqopt(sb)->files[type];
6452         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6453         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6454         int retries = 0;
6455         struct buffer_head *bh;
6456         handle_t *handle = journal_current_handle();
6457
6458         if (EXT4_SB(sb)->s_journal && !handle) {
6459                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6460                         " cancelled because transaction is not started",
6461                         (unsigned long long)off, (unsigned long long)len);
6462                 return -EIO;
6463         }
6464         /*
6465          * Since we account only one data block in transaction credits,
6466          * then it is impossible to cross a block boundary.
6467          */
6468         if (sb->s_blocksize - offset < len) {
6469                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6470                         " cancelled because not block aligned",
6471                         (unsigned long long)off, (unsigned long long)len);
6472                 return -EIO;
6473         }
6474
6475         do {
6476                 bh = ext4_bread(handle, inode, blk,
6477                                 EXT4_GET_BLOCKS_CREATE |
6478                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6479         } while (PTR_ERR(bh) == -ENOSPC &&
6480                  ext4_should_retry_alloc(inode->i_sb, &retries));
6481         if (IS_ERR(bh))
6482                 return PTR_ERR(bh);
6483         if (!bh)
6484                 goto out;
6485         BUFFER_TRACE(bh, "get write access");
6486         err = ext4_journal_get_write_access(handle, bh);
6487         if (err) {
6488                 brelse(bh);
6489                 return err;
6490         }
6491         lock_buffer(bh);
6492         memcpy(bh->b_data+offset, data, len);
6493         flush_dcache_page(bh->b_page);
6494         unlock_buffer(bh);
6495         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6496         brelse(bh);
6497 out:
6498         if (inode->i_size < off + len) {
6499                 i_size_write(inode, off + len);
6500                 EXT4_I(inode)->i_disksize = inode->i_size;
6501                 err2 = ext4_mark_inode_dirty(handle, inode);
6502                 if (unlikely(err2 && !err))
6503                         err = err2;
6504         }
6505         return err ? err : len;
6506 }
6507 #endif
6508
6509 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6510                        const char *dev_name, void *data)
6511 {
6512         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6513 }
6514
6515 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6516 static inline void register_as_ext2(void)
6517 {
6518         int err = register_filesystem(&ext2_fs_type);
6519         if (err)
6520                 printk(KERN_WARNING
6521                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6522 }
6523
6524 static inline void unregister_as_ext2(void)
6525 {
6526         unregister_filesystem(&ext2_fs_type);
6527 }
6528
6529 static inline int ext2_feature_set_ok(struct super_block *sb)
6530 {
6531         if (ext4_has_unknown_ext2_incompat_features(sb))
6532                 return 0;
6533         if (sb_rdonly(sb))
6534                 return 1;
6535         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6536                 return 0;
6537         return 1;
6538 }
6539 #else
6540 static inline void register_as_ext2(void) { }
6541 static inline void unregister_as_ext2(void) { }
6542 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6543 #endif
6544
6545 static inline void register_as_ext3(void)
6546 {
6547         int err = register_filesystem(&ext3_fs_type);
6548         if (err)
6549                 printk(KERN_WARNING
6550                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6551 }
6552
6553 static inline void unregister_as_ext3(void)
6554 {
6555         unregister_filesystem(&ext3_fs_type);
6556 }
6557
6558 static inline int ext3_feature_set_ok(struct super_block *sb)
6559 {
6560         if (ext4_has_unknown_ext3_incompat_features(sb))
6561                 return 0;
6562         if (!ext4_has_feature_journal(sb))
6563                 return 0;
6564         if (sb_rdonly(sb))
6565                 return 1;
6566         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6567                 return 0;
6568         return 1;
6569 }
6570
6571 static struct file_system_type ext4_fs_type = {
6572         .owner          = THIS_MODULE,
6573         .name           = "ext4",
6574         .mount          = ext4_mount,
6575         .kill_sb        = kill_block_super,
6576         .fs_flags       = FS_REQUIRES_DEV,
6577 };
6578 MODULE_ALIAS_FS("ext4");
6579
6580 /* Shared across all ext4 file systems */
6581 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6582
6583 static int __init ext4_init_fs(void)
6584 {
6585         int i, err;
6586
6587         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6588         ext4_li_info = NULL;
6589         mutex_init(&ext4_li_mtx);
6590
6591         /* Build-time check for flags consistency */
6592         ext4_check_flag_values();
6593
6594         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6595                 init_waitqueue_head(&ext4__ioend_wq[i]);
6596
6597         err = ext4_init_es();
6598         if (err)
6599                 return err;
6600
6601         err = ext4_init_pending();
6602         if (err)
6603                 goto out7;
6604
6605         err = ext4_init_post_read_processing();
6606         if (err)
6607                 goto out6;
6608
6609         err = ext4_init_pageio();
6610         if (err)
6611                 goto out5;
6612
6613         err = ext4_init_system_zone();
6614         if (err)
6615                 goto out4;
6616
6617         err = ext4_init_sysfs();
6618         if (err)
6619                 goto out3;
6620
6621         err = ext4_init_mballoc();
6622         if (err)
6623                 goto out2;
6624         err = init_inodecache();
6625         if (err)
6626                 goto out1;
6627
6628         err = ext4_fc_init_dentry_cache();
6629         if (err)
6630                 goto out05;
6631
6632         register_as_ext3();
6633         register_as_ext2();
6634         err = register_filesystem(&ext4_fs_type);
6635         if (err)
6636                 goto out;
6637
6638         return 0;
6639 out:
6640         unregister_as_ext2();
6641         unregister_as_ext3();
6642 out05:
6643         destroy_inodecache();
6644 out1:
6645         ext4_exit_mballoc();
6646 out2:
6647         ext4_exit_sysfs();
6648 out3:
6649         ext4_exit_system_zone();
6650 out4:
6651         ext4_exit_pageio();
6652 out5:
6653         ext4_exit_post_read_processing();
6654 out6:
6655         ext4_exit_pending();
6656 out7:
6657         ext4_exit_es();
6658
6659         return err;
6660 }
6661
6662 static void __exit ext4_exit_fs(void)
6663 {
6664         ext4_destroy_lazyinit_thread();
6665         unregister_as_ext2();
6666         unregister_as_ext3();
6667         unregister_filesystem(&ext4_fs_type);
6668         destroy_inodecache();
6669         ext4_exit_mballoc();
6670         ext4_exit_sysfs();
6671         ext4_exit_system_zone();
6672         ext4_exit_pageio();
6673         ext4_exit_post_read_processing();
6674         ext4_exit_es();
6675         ext4_exit_pending();
6676 }
6677
6678 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6679 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6680 MODULE_LICENSE("GPL");
6681 MODULE_SOFTDEP("pre: crc32c");
6682 module_init(ext4_init_fs)
6683 module_exit(ext4_exit_fs)