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 void ext4_update_super(struct super_block *sb);
  69 static int ext4_commit_super(struct super_block *sb);
  70 static int ext4_mark_recovery_complete(struct super_block *sb,
  71                                         struct ext4_super_block *es);
  72 static int ext4_clear_journal_err(struct super_block *sb,
  73                                   struct ext4_super_block *es);
  74 static int ext4_sync_fs(struct super_block *sb, int wait);
  75 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  76 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  77 static int ext4_unfreeze(struct super_block *sb);
  78 static int ext4_freeze(struct super_block *sb);
  79 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  80                        const char *dev_name, void *data);
  81 static inline int ext2_feature_set_ok(struct super_block *sb);
  82 static inline int ext3_feature_set_ok(struct super_block *sb);
  83 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  84 static void ext4_destroy_lazyinit_thread(void);
  85 static void ext4_unregister_li_request(struct super_block *sb);
  86 static void ext4_clear_request_list(void);
  87 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  88                                             unsigned int journal_inum);
  89
  90 /*
  91  * Lock ordering
  92  *
  93  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
  94  * i_mmap_rwsem (inode->i_mmap_rwsem)!
  95  *
  96  * page fault path:
  97  * mmap_lock -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
  98  *   page lock -> i_data_sem (rw)
  99  *
 100  * buffered write path:
 101  * sb_start_write -> i_mutex -> mmap_lock
 102  * sb_start_write -> i_mutex -> transaction start -> page lock ->
 103  *   i_data_sem (rw)
 104  *
 105  * truncate:
 106  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> i_mmap_rwsem (w) -> page lock
 107  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> transaction start ->
 108  *   i_data_sem (rw)
 109  *
 110  * direct IO:
 111  * sb_start_write -> i_mutex -> mmap_lock
 112  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
 113  *
 114  * writepages:
 115  * transaction start -> page lock(s) -> i_data_sem (rw)
 116  */
 117
 118 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 119 static struct file_system_type ext2_fs_type = {
 120         .owner          = THIS_MODULE,
 121         .name           = "ext2",
 122         .mount          = ext4_mount,
 123         .kill_sb        = kill_block_super,
 124         .fs_flags       = FS_REQUIRES_DEV,
 125 };
 126 MODULE_ALIAS_FS("ext2");
 127 MODULE_ALIAS("ext2");
 128 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
 129 #else
 130 #define IS_EXT2_SB(sb) (0)
 131 #endif
 132
 133
 134 static struct file_system_type ext3_fs_type = {
 135         .owner          = THIS_MODULE,
 136         .name           = "ext3",
 137         .mount          = ext4_mount,
 138         .kill_sb        = kill_block_super,
 139         .fs_flags       = FS_REQUIRES_DEV,
 140 };
 141 MODULE_ALIAS_FS("ext3");
 142 MODULE_ALIAS("ext3");
 143 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 144
 145
 146 static inline void __ext4_read_bh(struct buffer_head *bh, int op_flags,
 147                                   bh_end_io_t *end_io)
 148 {
 149         /*
 150          * buffer's verified bit is no longer valid after reading from
 151          * disk again due to write out error, clear it to make sure we
 152          * recheck the buffer contents.
 153          */
 154         clear_buffer_verified(bh);
 155
 156         bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
 157         get_bh(bh);
 158         submit_bh(REQ_OP_READ, op_flags, bh);
 159 }
 160
 161 void ext4_read_bh_nowait(struct buffer_head *bh, int op_flags,
 162                          bh_end_io_t *end_io)
 163 {
 164         BUG_ON(!buffer_locked(bh));
 165
 166         if (ext4_buffer_uptodate(bh)) {
 167                 unlock_buffer(bh);
 168                 return;
 169         }
 170         __ext4_read_bh(bh, op_flags, end_io);
 171 }
 172
 173 int ext4_read_bh(struct buffer_head *bh, int op_flags, bh_end_io_t *end_io)
 174 {
 175         BUG_ON(!buffer_locked(bh));
 176
 177         if (ext4_buffer_uptodate(bh)) {
 178                 unlock_buffer(bh);
 179                 return 0;
 180         }
 181
 182         __ext4_read_bh(bh, op_flags, end_io);
 183
 184         wait_on_buffer(bh);
 185         if (buffer_uptodate(bh))
 186                 return 0;
 187         return -EIO;
 188 }
 189
 190 int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait)
 191 {
 192         if (trylock_buffer(bh)) {
 193                 if (wait)
 194                         return ext4_read_bh(bh, op_flags, NULL);
 195                 ext4_read_bh_nowait(bh, op_flags, NULL);
 196                 return 0;
 197         }
 198         if (wait) {
 199                 wait_on_buffer(bh);
 200                 if (buffer_uptodate(bh))
 201                         return 0;
 202                 return -EIO;
 203         }
 204         return 0;
 205 }
 206
 207 /*
 208  * This works like __bread_gfp() except it uses ERR_PTR for error
 209  * returns.  Currently with sb_bread it's impossible to distinguish
 210  * between ENOMEM and EIO situations (since both result in a NULL
 211  * return.
 212  */
 213 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
 214                                                sector_t block, int op_flags,
 215                                                gfp_t gfp)
 216 {
 217         struct buffer_head *bh;
 218         int ret;
 219
 220         bh = sb_getblk_gfp(sb, block, gfp);
 221         if (bh == NULL)
 222                 return ERR_PTR(-ENOMEM);
 223         if (ext4_buffer_uptodate(bh))
 224                 return bh;
 225
 226         ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
 227         if (ret) {
 228                 put_bh(bh);
 229                 return ERR_PTR(ret);
 230         }
 231         return bh;
 232 }
 233
 234 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
 235                                    int op_flags)
 236 {
 237         return __ext4_sb_bread_gfp(sb, block, op_flags, __GFP_MOVABLE);
 238 }
 239
 240 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
 241                                             sector_t block)
 242 {
 243         return __ext4_sb_bread_gfp(sb, block, 0, 0);
 244 }
 245
 246 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
 247 {
 248         struct buffer_head *bh = sb_getblk_gfp(sb, block, 0);
 249
 250         if (likely(bh)) {
 251                 ext4_read_bh_lock(bh, REQ_RAHEAD, false);
 252                 brelse(bh);
 253         }
 254 }
 255
 256 static int ext4_verify_csum_type(struct super_block *sb,
 257                                  struct ext4_super_block *es)
 258 {
 259         if (!ext4_has_feature_metadata_csum(sb))
 260                 return 1;
 261
 262         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 263 }
 264
 265 static __le32 ext4_superblock_csum(struct super_block *sb,
 266                                    struct ext4_super_block *es)
 267 {
 268         struct ext4_sb_info *sbi = EXT4_SB(sb);
 269         int offset = offsetof(struct ext4_super_block, s_checksum);
 270         __u32 csum;
 271
 272         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 273
 274         return cpu_to_le32(csum);
 275 }
 276
 277 static int ext4_superblock_csum_verify(struct super_block *sb,
 278                                        struct ext4_super_block *es)
 279 {
 280         if (!ext4_has_metadata_csum(sb))
 281                 return 1;
 282
 283         return es->s_checksum == ext4_superblock_csum(sb, es);
 284 }
 285
 286 void ext4_superblock_csum_set(struct super_block *sb)
 287 {
 288         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 289
 290         if (!ext4_has_metadata_csum(sb))
 291                 return;
 292
 293         es->s_checksum = ext4_superblock_csum(sb, es);
 294 }
 295
 296 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 297                                struct ext4_group_desc *bg)
 298 {
 299         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 300                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 301                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 302 }
 303
 304 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 305                                struct ext4_group_desc *bg)
 306 {
 307         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 308                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 309                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 310 }
 311
 312 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 313                               struct ext4_group_desc *bg)
 314 {
 315         return le32_to_cpu(bg->bg_inode_table_lo) |
 316                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 317                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 318 }
 319
 320 __u32 ext4_free_group_clusters(struct super_block *sb,
 321                                struct ext4_group_desc *bg)
 322 {
 323         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 324                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 325                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 326 }
 327
 328 __u32 ext4_free_inodes_count(struct super_block *sb,
 329                               struct ext4_group_desc *bg)
 330 {
 331         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 332                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 333                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 334 }
 335
 336 __u32 ext4_used_dirs_count(struct super_block *sb,
 337                               struct ext4_group_desc *bg)
 338 {
 339         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 340                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 341                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 342 }
 343
 344 __u32 ext4_itable_unused_count(struct super_block *sb,
 345                               struct ext4_group_desc *bg)
 346 {
 347         return le16_to_cpu(bg->bg_itable_unused_lo) |
 348                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 349                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 350 }
 351
 352 void ext4_block_bitmap_set(struct super_block *sb,
 353                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 354 {
 355         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 356         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 357                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 358 }
 359
 360 void ext4_inode_bitmap_set(struct super_block *sb,
 361                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 362 {
 363         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 364         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 365                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 366 }
 367
 368 void ext4_inode_table_set(struct super_block *sb,
 369                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 370 {
 371         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 372         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 373                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 374 }
 375
 376 void ext4_free_group_clusters_set(struct super_block *sb,
 377                                   struct ext4_group_desc *bg, __u32 count)
 378 {
 379         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 380         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 381                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 382 }
 383
 384 void ext4_free_inodes_set(struct super_block *sb,
 385                           struct ext4_group_desc *bg, __u32 count)
 386 {
 387         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 388         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 389                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 390 }
 391
 392 void ext4_used_dirs_set(struct super_block *sb,
 393                           struct ext4_group_desc *bg, __u32 count)
 394 {
 395         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 396         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 397                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 398 }
 399
 400 void ext4_itable_unused_set(struct super_block *sb,
 401                           struct ext4_group_desc *bg, __u32 count)
 402 {
 403         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 404         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 405                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 406 }
 407
 408 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi, time64_t now)
 409 {
 410         now = clamp_val(now, 0, (1ull << 40) - 1);
 411
 412         *lo = cpu_to_le32(lower_32_bits(now));
 413         *hi = upper_32_bits(now);
 414 }
 415
 416 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 417 {
 418         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 419 }
 420 #define ext4_update_tstamp(es, tstamp) \
 421         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi, \
 422                              ktime_get_real_seconds())
 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_sb_info *sbi = EXT4_SB(sb);
 595
 596         /* We default to EFSCORRUPTED error... */
 597         if (error == 0)
 598                 error = EFSCORRUPTED;
 599
 600         spin_lock(&sbi->s_error_lock);
 601         sbi->s_add_error_count++;
 602         sbi->s_last_error_code = error;
 603         sbi->s_last_error_line = line;
 604         sbi->s_last_error_ino = ino;
 605         sbi->s_last_error_block = block;
 606         sbi->s_last_error_func = func;
 607         sbi->s_last_error_time = ktime_get_real_seconds();
 608         if (!sbi->s_first_error_time) {
 609                 sbi->s_first_error_code = error;
 610                 sbi->s_first_error_line = line;
 611                 sbi->s_first_error_ino = ino;
 612                 sbi->s_first_error_block = block;
 613                 sbi->s_first_error_func = func;
 614                 sbi->s_first_error_time = sbi->s_last_error_time;
 615         }
 616         spin_unlock(&sbi->s_error_lock);
 617 }
 618
 619 /* Deal with the reporting of failure conditions on a filesystem such as
 620  * inconsistencies detected or read IO failures.
 621  *
 622  * On ext2, we can store the error state of the filesystem in the
 623  * superblock.  That is not possible on ext4, because we may have other
 624  * write ordering constraints on the superblock which prevent us from
 625  * writing it out straight away; and given that the journal is about to
 626  * be aborted, we can't rely on the current, or future, transactions to
 627  * write out the superblock safely.
 628  *
 629  * We'll just use the jbd2_journal_abort() error code to record an error in
 630  * the journal instead.  On recovery, the journal will complain about
 631  * that error until we've noted it down and cleared it.
 632  *
 633  * If force_ro is set, we unconditionally force the filesystem into an
 634  * ABORT|READONLY state, unless the error response on the fs has been set to
 635  * panic in which case we take the easy way out and panic immediately. This is
 636  * used to deal with unrecoverable failures such as journal IO errors or ENOMEM
 637  * at a critical moment in log management.
 638  */
 639 static void ext4_handle_error(struct super_block *sb, bool force_ro, int error,
 640                               __u32 ino, __u64 block,
 641                               const char *func, unsigned int line)
 642 {
 643         journal_t *journal = EXT4_SB(sb)->s_journal;
 644         bool continue_fs = !force_ro && test_opt(sb, ERRORS_CONT);
 645
 646         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 647         if (test_opt(sb, WARN_ON_ERROR))
 648                 WARN_ON_ONCE(1);
 649
 650         if (!continue_fs && !sb_rdonly(sb)) {
 651                 ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
 652                 if (journal)
 653                         jbd2_journal_abort(journal, -EIO);
 654         }
 655
 656         if (!bdev_read_only(sb->s_bdev)) {
 657                 save_error_info(sb, error, ino, block, func, line);
 658                 /*
 659                  * In case the fs should keep running, we need to writeout
 660                  * superblock through the journal. Due to lock ordering
 661                  * constraints, it may not be safe to do it right here so we
 662                  * defer superblock flushing to a workqueue.
 663                  */
 664                 if (continue_fs)
 665                         schedule_work(&EXT4_SB(sb)->s_error_work);
 666                 else
 667                         ext4_commit_super(sb);
 668         }
 669
 670         if (sb_rdonly(sb) || continue_fs)
 671                 return;
 672
 673         /*
 674          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 675          * could panic during 'reboot -f' as the underlying device got already
 676          * disabled.
 677          */
 678         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
 679                 panic("EXT4-fs (device %s): panic forced after error\n",
 680                         sb->s_id);
 681         }
 682         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 683         /*
 684          * Make sure updated value of ->s_mount_flags will be visible before
 685          * ->s_flags update
 686          */
 687         smp_wmb();
 688         sb->s_flags |= SB_RDONLY;
 689 }
 690
 691 static void flush_stashed_error_work(struct work_struct *work)
 692 {
 693         struct ext4_sb_info *sbi = container_of(work, struct ext4_sb_info,
 694                                                 s_error_work);
 695         journal_t *journal = sbi->s_journal;
 696         handle_t *handle;
 697
 698         /*
 699          * If the journal is still running, we have to write out superblock
 700          * through the journal to avoid collisions of other journalled sb
 701          * updates.
 702          *
 703          * We use directly jbd2 functions here to avoid recursing back into
 704          * ext4 error handling code during handling of previous errors.
 705          */
 706         if (!sb_rdonly(sbi->s_sb) && journal) {
 707                 handle = jbd2_journal_start(journal, 1);
 708                 if (IS_ERR(handle))
 709                         goto write_directly;
 710                 if (jbd2_journal_get_write_access(handle, sbi->s_sbh)) {
 711                         jbd2_journal_stop(handle);
 712                         goto write_directly;
 713                 }
 714                 ext4_update_super(sbi->s_sb);
 715                 if (jbd2_journal_dirty_metadata(handle, sbi->s_sbh)) {
 716                         jbd2_journal_stop(handle);
 717                         goto write_directly;
 718                 }
 719                 jbd2_journal_stop(handle);
 720                 return;
 721         }
 722 write_directly:
 723         /*
 724          * Write through journal failed. Write sb directly to get error info
 725          * out and hope for the best.
 726          */
 727         ext4_commit_super(sbi->s_sb);
 728 }
 729
 730 #define ext4_error_ratelimit(sb)                                        \
 731                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 732                              "EXT4-fs error")
 733
 734 void __ext4_error(struct super_block *sb, const char *function,
 735                   unsigned int line, bool force_ro, int error, __u64 block,
 736                   const char *fmt, ...)
 737 {
 738         struct va_format vaf;
 739         va_list args;
 740
 741         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 742                 return;
 743
 744         trace_ext4_error(sb, function, line);
 745         if (ext4_error_ratelimit(sb)) {
 746                 va_start(args, fmt);
 747                 vaf.fmt = fmt;
 748                 vaf.va = &args;
 749                 printk(KERN_CRIT
 750                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 751                        sb->s_id, function, line, current->comm, &vaf);
 752                 va_end(args);
 753         }
 754         ext4_handle_error(sb, force_ro, error, 0, block, function, line);
 755 }
 756
 757 void __ext4_error_inode(struct inode *inode, const char *function,
 758                         unsigned int line, ext4_fsblk_t block, int error,
 759                         const char *fmt, ...)
 760 {
 761         va_list args;
 762         struct va_format vaf;
 763
 764         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 765                 return;
 766
 767         trace_ext4_error(inode->i_sb, function, line);
 768         if (ext4_error_ratelimit(inode->i_sb)) {
 769                 va_start(args, fmt);
 770                 vaf.fmt = fmt;
 771                 vaf.va = &args;
 772                 if (block)
 773                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 774                                "inode #%lu: block %llu: comm %s: %pV\n",
 775                                inode->i_sb->s_id, function, line, inode->i_ino,
 776                                block, current->comm, &vaf);
 777                 else
 778                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 779                                "inode #%lu: comm %s: %pV\n",
 780                                inode->i_sb->s_id, function, line, inode->i_ino,
 781                                current->comm, &vaf);
 782                 va_end(args);
 783         }
 784         ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
 785                           function, line);
 786 }
 787
 788 void __ext4_error_file(struct file *file, const char *function,
 789                        unsigned int line, ext4_fsblk_t block,
 790                        const char *fmt, ...)
 791 {
 792         va_list args;
 793         struct va_format vaf;
 794         struct inode *inode = file_inode(file);
 795         char pathname[80], *path;
 796
 797         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 798                 return;
 799
 800         trace_ext4_error(inode->i_sb, function, line);
 801         if (ext4_error_ratelimit(inode->i_sb)) {
 802                 path = file_path(file, pathname, sizeof(pathname));
 803                 if (IS_ERR(path))
 804                         path = "(unknown)";
 805                 va_start(args, fmt);
 806                 vaf.fmt = fmt;
 807                 vaf.va = &args;
 808                 if (block)
 809                         printk(KERN_CRIT
 810                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 811                                "block %llu: comm %s: path %s: %pV\n",
 812                                inode->i_sb->s_id, function, line, inode->i_ino,
 813                                block, current->comm, path, &vaf);
 814                 else
 815                         printk(KERN_CRIT
 816                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 817                                "comm %s: path %s: %pV\n",
 818                                inode->i_sb->s_id, function, line, inode->i_ino,
 819                                current->comm, path, &vaf);
 820                 va_end(args);
 821         }
 822         ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
 823                           function, line);
 824 }
 825
 826 const char *ext4_decode_error(struct super_block *sb, int errno,
 827                               char nbuf[16])
 828 {
 829         char *errstr = NULL;
 830
 831         switch (errno) {
 832         case -EFSCORRUPTED:
 833                 errstr = "Corrupt filesystem";
 834                 break;
 835         case -EFSBADCRC:
 836                 errstr = "Filesystem failed CRC";
 837                 break;
 838         case -EIO:
 839                 errstr = "IO failure";
 840                 break;
 841         case -ENOMEM:
 842                 errstr = "Out of memory";
 843                 break;
 844         case -EROFS:
 845                 if (!sb || (EXT4_SB(sb)->s_journal &&
 846                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 847                         errstr = "Journal has aborted";
 848                 else
 849                         errstr = "Readonly filesystem";
 850                 break;
 851         default:
 852                 /* If the caller passed in an extra buffer for unknown
 853                  * errors, textualise them now.  Else we just return
 854                  * NULL. */
 855                 if (nbuf) {
 856                         /* Check for truncated error codes... */
 857                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 858                                 errstr = nbuf;
 859                 }
 860                 break;
 861         }
 862
 863         return errstr;
 864 }
 865
 866 /* __ext4_std_error decodes expected errors from journaling functions
 867  * automatically and invokes the appropriate error response.  */
 868
 869 void __ext4_std_error(struct super_block *sb, const char *function,
 870                       unsigned int line, int errno)
 871 {
 872         char nbuf[16];
 873         const char *errstr;
 874
 875         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 876                 return;
 877
 878         /* Special case: if the error is EROFS, and we're not already
 879          * inside a transaction, then there's really no point in logging
 880          * an error. */
 881         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 882                 return;
 883
 884         if (ext4_error_ratelimit(sb)) {
 885                 errstr = ext4_decode_error(sb, errno, nbuf);
 886                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 887                        sb->s_id, function, line, errstr);
 888         }
 889
 890         ext4_handle_error(sb, false, -errno, 0, 0, function, line);
 891 }
 892
 893 void __ext4_msg(struct super_block *sb,
 894                 const char *prefix, const char *fmt, ...)
 895 {
 896         struct va_format vaf;
 897         va_list args;
 898
 899         atomic_inc(&EXT4_SB(sb)->s_msg_count);
 900         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 901                 return;
 902
 903         va_start(args, fmt);
 904         vaf.fmt = fmt;
 905         vaf.va = &args;
 906         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 907         va_end(args);
 908 }
 909
 910 static int ext4_warning_ratelimit(struct super_block *sb)
 911 {
 912         atomic_inc(&EXT4_SB(sb)->s_warning_count);
 913         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
 914                             "EXT4-fs warning");
 915 }
 916
 917 void __ext4_warning(struct super_block *sb, const char *function,
 918                     unsigned int line, const char *fmt, ...)
 919 {
 920         struct va_format vaf;
 921         va_list args;
 922
 923         if (!ext4_warning_ratelimit(sb))
 924                 return;
 925
 926         va_start(args, fmt);
 927         vaf.fmt = fmt;
 928         vaf.va = &args;
 929         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 930                sb->s_id, function, line, &vaf);
 931         va_end(args);
 932 }
 933
 934 void __ext4_warning_inode(const struct inode *inode, const char *function,
 935                           unsigned int line, const char *fmt, ...)
 936 {
 937         struct va_format vaf;
 938         va_list args;
 939
 940         if (!ext4_warning_ratelimit(inode->i_sb))
 941                 return;
 942
 943         va_start(args, fmt);
 944         vaf.fmt = fmt;
 945         vaf.va = &args;
 946         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 947                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 948                function, line, inode->i_ino, current->comm, &vaf);
 949         va_end(args);
 950 }
 951
 952 void __ext4_grp_locked_error(const char *function, unsigned int line,
 953                              struct super_block *sb, ext4_group_t grp,
 954                              unsigned long ino, ext4_fsblk_t block,
 955                              const char *fmt, ...)
 956 __releases(bitlock)
 957 __acquires(bitlock)
 958 {
 959         struct va_format vaf;
 960         va_list args;
 961
 962         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 963                 return;
 964
 965         trace_ext4_error(sb, function, line);
 966         if (ext4_error_ratelimit(sb)) {
 967                 va_start(args, fmt);
 968                 vaf.fmt = fmt;
 969                 vaf.va = &args;
 970                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 971                        sb->s_id, function, line, grp);
 972                 if (ino)
 973                         printk(KERN_CONT "inode %lu: ", ino);
 974                 if (block)
 975                         printk(KERN_CONT "block %llu:",
 976                                (unsigned long long) block);
 977                 printk(KERN_CONT "%pV\n", &vaf);
 978                 va_end(args);
 979         }
 980
 981         if (test_opt(sb, ERRORS_CONT)) {
 982                 if (test_opt(sb, WARN_ON_ERROR))
 983                         WARN_ON_ONCE(1);
 984                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 985                 if (!bdev_read_only(sb->s_bdev)) {
 986                         save_error_info(sb, EFSCORRUPTED, ino, block, function,
 987                                         line);
 988                         schedule_work(&EXT4_SB(sb)->s_error_work);
 989                 }
 990                 return;
 991         }
 992         ext4_unlock_group(sb, grp);
 993         ext4_handle_error(sb, false, EFSCORRUPTED, ino, block, function, line);
 994         /*
 995          * We only get here in the ERRORS_RO case; relocking the group
 996          * may be dangerous, but nothing bad will happen since the
 997          * filesystem will have already been marked read/only and the
 998          * journal has been aborted.  We return 1 as a hint to callers
 999          * who might what to use the return value from
1000          * ext4_grp_locked_error() to distinguish between the
1001          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1002          * aggressively from the ext4 function in question, with a
1003          * more appropriate error code.
1004          */
1005         ext4_lock_group(sb, grp);
1006         return;
1007 }
1008
1009 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1010                                      ext4_group_t group,
1011                                      unsigned int flags)
1012 {
1013         struct ext4_sb_info *sbi = EXT4_SB(sb);
1014         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1015         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1016         int ret;
1017
1018         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1019                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1020                                             &grp->bb_state);
1021                 if (!ret)
1022                         percpu_counter_sub(&sbi->s_freeclusters_counter,
1023                                            grp->bb_free);
1024         }
1025
1026         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1027                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1028                                             &grp->bb_state);
1029                 if (!ret && gdp) {
1030                         int count;
1031
1032                         count = ext4_free_inodes_count(sb, gdp);
1033                         percpu_counter_sub(&sbi->s_freeinodes_counter,
1034                                            count);
1035                 }
1036         }
1037 }
1038
1039 void ext4_update_dynamic_rev(struct super_block *sb)
1040 {
1041         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1042
1043         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1044                 return;
1045
1046         ext4_warning(sb,
1047                      "updating to rev %d because of new feature flag, "
1048                      "running e2fsck is recommended",
1049                      EXT4_DYNAMIC_REV);
1050
1051         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1052         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1053         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1054         /* leave es->s_feature_*compat flags alone */
1055         /* es->s_uuid will be set by e2fsck if empty */
1056
1057         /*
1058          * The rest of the superblock fields should be zero, and if not it
1059          * means they are likely already in use, so leave them alone.  We
1060          * can leave it up to e2fsck to clean up any inconsistencies there.
1061          */
1062 }
1063
1064 /*
1065  * Open the external journal device
1066  */
1067 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
1068 {
1069         struct block_device *bdev;
1070
1071         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
1072         if (IS_ERR(bdev))
1073                 goto fail;
1074         return bdev;
1075
1076 fail:
1077         ext4_msg(sb, KERN_ERR,
1078                  "failed to open journal device unknown-block(%u,%u) %ld",
1079                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
1080         return NULL;
1081 }
1082
1083 /*
1084  * Release the journal device
1085  */
1086 static void ext4_blkdev_put(struct block_device *bdev)
1087 {
1088         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1089 }
1090
1091 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
1092 {
1093         struct block_device *bdev;
1094         bdev = sbi->s_journal_bdev;
1095         if (bdev) {
1096                 ext4_blkdev_put(bdev);
1097                 sbi->s_journal_bdev = NULL;
1098         }
1099 }
1100
1101 static inline struct inode *orphan_list_entry(struct list_head *l)
1102 {
1103         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1104 }
1105
1106 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1107 {
1108         struct list_head *l;
1109
1110         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1111                  le32_to_cpu(sbi->s_es->s_last_orphan));
1112
1113         printk(KERN_ERR "sb_info orphan list:\n");
1114         list_for_each(l, &sbi->s_orphan) {
1115                 struct inode *inode = orphan_list_entry(l);
1116                 printk(KERN_ERR "  "
1117                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1118                        inode->i_sb->s_id, inode->i_ino, inode,
1119                        inode->i_mode, inode->i_nlink,
1120                        NEXT_ORPHAN(inode));
1121         }
1122 }
1123
1124 #ifdef CONFIG_QUOTA
1125 static int ext4_quota_off(struct super_block *sb, int type);
1126
1127 static inline void ext4_quota_off_umount(struct super_block *sb)
1128 {
1129         int type;
1130
1131         /* Use our quota_off function to clear inode flags etc. */
1132         for (type = 0; type < EXT4_MAXQUOTAS; type++)
1133                 ext4_quota_off(sb, type);
1134 }
1135
1136 /*
1137  * This is a helper function which is used in the mount/remount
1138  * codepaths (which holds s_umount) to fetch the quota file name.
1139  */
1140 static inline char *get_qf_name(struct super_block *sb,
1141                                 struct ext4_sb_info *sbi,
1142                                 int type)
1143 {
1144         return rcu_dereference_protected(sbi->s_qf_names[type],
1145                                          lockdep_is_held(&sb->s_umount));
1146 }
1147 #else
1148 static inline void ext4_quota_off_umount(struct super_block *sb)
1149 {
1150 }
1151 #endif
1152
1153 static void ext4_put_super(struct super_block *sb)
1154 {
1155         struct ext4_sb_info *sbi = EXT4_SB(sb);
1156         struct ext4_super_block *es = sbi->s_es;
1157         struct buffer_head **group_desc;
1158         struct flex_groups **flex_groups;
1159         int aborted = 0;
1160         int i, err;
1161
1162         ext4_unregister_li_request(sb);
1163         ext4_quota_off_umount(sb);
1164
1165         flush_work(&sbi->s_error_work);
1166         destroy_workqueue(sbi->rsv_conversion_wq);
1167
1168         /*
1169          * Unregister sysfs before destroying jbd2 journal.
1170          * Since we could still access attr_journal_task attribute via sysfs
1171          * path which could have sbi->s_journal->j_task as NULL
1172          */
1173         ext4_unregister_sysfs(sb);
1174
1175         if (sbi->s_journal) {
1176                 aborted = is_journal_aborted(sbi->s_journal);
1177                 err = jbd2_journal_destroy(sbi->s_journal);
1178                 sbi->s_journal = NULL;
1179                 if ((err < 0) && !aborted) {
1180                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1181                 }
1182         }
1183
1184         ext4_es_unregister_shrinker(sbi);
1185         del_timer_sync(&sbi->s_err_report);
1186         ext4_release_system_zone(sb);
1187         ext4_mb_release(sb);
1188         ext4_ext_release(sb);
1189
1190         if (!sb_rdonly(sb) && !aborted) {
1191                 ext4_clear_feature_journal_needs_recovery(sb);
1192                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1193         }
1194         if (!sb_rdonly(sb))
1195                 ext4_commit_super(sb);
1196
1197         rcu_read_lock();
1198         group_desc = rcu_dereference(sbi->s_group_desc);
1199         for (i = 0; i < sbi->s_gdb_count; i++)
1200                 brelse(group_desc[i]);
1201         kvfree(group_desc);
1202         flex_groups = rcu_dereference(sbi->s_flex_groups);
1203         if (flex_groups) {
1204                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1205                         kvfree(flex_groups[i]);
1206                 kvfree(flex_groups);
1207         }
1208         rcu_read_unlock();
1209         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1210         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1211         percpu_counter_destroy(&sbi->s_dirs_counter);
1212         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1213         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1214 #ifdef CONFIG_QUOTA
1215         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1216                 kfree(get_qf_name(sb, sbi, i));
1217 #endif
1218
1219         /* Debugging code just in case the in-memory inode orphan list
1220          * isn't empty.  The on-disk one can be non-empty if we've
1221          * detected an error and taken the fs readonly, but the
1222          * in-memory list had better be clean by this point. */
1223         if (!list_empty(&sbi->s_orphan))
1224                 dump_orphan_list(sb, sbi);
1225         ASSERT(list_empty(&sbi->s_orphan));
1226
1227         sync_blockdev(sb->s_bdev);
1228         invalidate_bdev(sb->s_bdev);
1229         if (sbi->s_journal_bdev && sbi->s_journal_bdev != sb->s_bdev) {
1230                 /*
1231                  * Invalidate the journal device's buffers.  We don't want them
1232                  * floating about in memory - the physical journal device may
1233                  * hotswapped, and it breaks the `ro-after' testing code.
1234                  */
1235                 sync_blockdev(sbi->s_journal_bdev);
1236                 invalidate_bdev(sbi->s_journal_bdev);
1237                 ext4_blkdev_remove(sbi);
1238         }
1239
1240         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1241         sbi->s_ea_inode_cache = NULL;
1242
1243         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1244         sbi->s_ea_block_cache = NULL;
1245
1246         if (sbi->s_mmp_tsk)
1247                 kthread_stop(sbi->s_mmp_tsk);
1248         brelse(sbi->s_sbh);
1249         sb->s_fs_info = NULL;
1250         /*
1251          * Now that we are completely done shutting down the
1252          * superblock, we need to actually destroy the kobject.
1253          */
1254         kobject_put(&sbi->s_kobj);
1255         wait_for_completion(&sbi->s_kobj_unregister);
1256         if (sbi->s_chksum_driver)
1257                 crypto_free_shash(sbi->s_chksum_driver);
1258         kfree(sbi->s_blockgroup_lock);
1259         fs_put_dax(sbi->s_daxdev);
1260         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1261 #ifdef CONFIG_UNICODE
1262         utf8_unload(sb->s_encoding);
1263 #endif
1264         kfree(sbi);
1265 }
1266
1267 static struct kmem_cache *ext4_inode_cachep;
1268
1269 /*
1270  * Called inside transaction, so use GFP_NOFS
1271  */
1272 static struct inode *ext4_alloc_inode(struct super_block *sb)
1273 {
1274         struct ext4_inode_info *ei;
1275
1276         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1277         if (!ei)
1278                 return NULL;
1279
1280         inode_set_iversion(&ei->vfs_inode, 1);
1281         spin_lock_init(&ei->i_raw_lock);
1282         INIT_LIST_HEAD(&ei->i_prealloc_list);
1283         atomic_set(&ei->i_prealloc_active, 0);
1284         spin_lock_init(&ei->i_prealloc_lock);
1285         ext4_es_init_tree(&ei->i_es_tree);
1286         rwlock_init(&ei->i_es_lock);
1287         INIT_LIST_HEAD(&ei->i_es_list);
1288         ei->i_es_all_nr = 0;
1289         ei->i_es_shk_nr = 0;
1290         ei->i_es_shrink_lblk = 0;
1291         ei->i_reserved_data_blocks = 0;
1292         spin_lock_init(&(ei->i_block_reservation_lock));
1293         ext4_init_pending_tree(&ei->i_pending_tree);
1294 #ifdef CONFIG_QUOTA
1295         ei->i_reserved_quota = 0;
1296         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1297 #endif
1298         ei->jinode = NULL;
1299         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1300         spin_lock_init(&ei->i_completed_io_lock);
1301         ei->i_sync_tid = 0;
1302         ei->i_datasync_tid = 0;
1303         atomic_set(&ei->i_unwritten, 0);
1304         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1305         ext4_fc_init_inode(&ei->vfs_inode);
1306         mutex_init(&ei->i_fc_lock);
1307         return &ei->vfs_inode;
1308 }
1309
1310 static int ext4_drop_inode(struct inode *inode)
1311 {
1312         int drop = generic_drop_inode(inode);
1313
1314         if (!drop)
1315                 drop = fscrypt_drop_inode(inode);
1316
1317         trace_ext4_drop_inode(inode, drop);
1318         return drop;
1319 }
1320
1321 static void ext4_free_in_core_inode(struct inode *inode)
1322 {
1323         fscrypt_free_inode(inode);
1324         if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1325                 pr_warn("%s: inode %ld still in fc list",
1326                         __func__, inode->i_ino);
1327         }
1328         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1329 }
1330
1331 static void ext4_destroy_inode(struct inode *inode)
1332 {
1333         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1334                 ext4_msg(inode->i_sb, KERN_ERR,
1335                          "Inode %lu (%p): orphan list check failed!",
1336                          inode->i_ino, EXT4_I(inode));
1337                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1338                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1339                                 true);
1340                 dump_stack();
1341         }
1342 }
1343
1344 static void init_once(void *foo)
1345 {
1346         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1347
1348         INIT_LIST_HEAD(&ei->i_orphan);
1349         init_rwsem(&ei->xattr_sem);
1350         init_rwsem(&ei->i_data_sem);
1351         init_rwsem(&ei->i_mmap_sem);
1352         inode_init_once(&ei->vfs_inode);
1353         ext4_fc_init_inode(&ei->vfs_inode);
1354 }
1355
1356 static int __init init_inodecache(void)
1357 {
1358         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1359                                 sizeof(struct ext4_inode_info), 0,
1360                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1361                                         SLAB_ACCOUNT),
1362                                 offsetof(struct ext4_inode_info, i_data),
1363                                 sizeof_field(struct ext4_inode_info, i_data),
1364                                 init_once);
1365         if (ext4_inode_cachep == NULL)
1366                 return -ENOMEM;
1367         return 0;
1368 }
1369
1370 static void destroy_inodecache(void)
1371 {
1372         /*
1373          * Make sure all delayed rcu free inodes are flushed before we
1374          * destroy cache.
1375          */
1376         rcu_barrier();
1377         kmem_cache_destroy(ext4_inode_cachep);
1378 }
1379
1380 void ext4_clear_inode(struct inode *inode)
1381 {
1382         ext4_fc_del(inode);
1383         invalidate_inode_buffers(inode);
1384         clear_inode(inode);
1385         ext4_discard_preallocations(inode, 0);
1386         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1387         dquot_drop(inode);
1388         if (EXT4_I(inode)->jinode) {
1389                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1390                                                EXT4_I(inode)->jinode);
1391                 jbd2_free_inode(EXT4_I(inode)->jinode);
1392                 EXT4_I(inode)->jinode = NULL;
1393         }
1394         fscrypt_put_encryption_info(inode);
1395         fsverity_cleanup_inode(inode);
1396 }
1397
1398 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1399                                         u64 ino, u32 generation)
1400 {
1401         struct inode *inode;
1402
1403         /*
1404          * Currently we don't know the generation for parent directory, so
1405          * a generation of 0 means "accept any"
1406          */
1407         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1408         if (IS_ERR(inode))
1409                 return ERR_CAST(inode);
1410         if (generation && inode->i_generation != generation) {
1411                 iput(inode);
1412                 return ERR_PTR(-ESTALE);
1413         }
1414
1415         return inode;
1416 }
1417
1418 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1419                                         int fh_len, int fh_type)
1420 {
1421         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1422                                     ext4_nfs_get_inode);
1423 }
1424
1425 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1426                                         int fh_len, int fh_type)
1427 {
1428         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1429                                     ext4_nfs_get_inode);
1430 }
1431
1432 static int ext4_nfs_commit_metadata(struct inode *inode)
1433 {
1434         struct writeback_control wbc = {
1435                 .sync_mode = WB_SYNC_ALL
1436         };
1437
1438         trace_ext4_nfs_commit_metadata(inode);
1439         return ext4_write_inode(inode, &wbc);
1440 }
1441
1442 /*
1443  * Try to release metadata pages (indirect blocks, directories) which are
1444  * mapped via the block device.  Since these pages could have journal heads
1445  * which would prevent try_to_free_buffers() from freeing them, we must use
1446  * jbd2 layer's try_to_free_buffers() function to release them.
1447  */
1448 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1449                                  gfp_t wait)
1450 {
1451         journal_t *journal = EXT4_SB(sb)->s_journal;
1452
1453         WARN_ON(PageChecked(page));
1454         if (!page_has_buffers(page))
1455                 return 0;
1456         if (journal)
1457                 return jbd2_journal_try_to_free_buffers(journal, page);
1458
1459         return try_to_free_buffers(page);
1460 }
1461
1462 #ifdef CONFIG_FS_ENCRYPTION
1463 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1464 {
1465         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1466                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1467 }
1468
1469 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1470                                                         void *fs_data)
1471 {
1472         handle_t *handle = fs_data;
1473         int res, res2, credits, retries = 0;
1474
1475         /*
1476          * Encrypting the root directory is not allowed because e2fsck expects
1477          * lost+found to exist and be unencrypted, and encrypting the root
1478          * directory would imply encrypting the lost+found directory as well as
1479          * the filename "lost+found" itself.
1480          */
1481         if (inode->i_ino == EXT4_ROOT_INO)
1482                 return -EPERM;
1483
1484         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1485                 return -EINVAL;
1486
1487         if (ext4_test_inode_flag(inode, EXT4_INODE_DAX))
1488                 return -EOPNOTSUPP;
1489
1490         res = ext4_convert_inline_data(inode);
1491         if (res)
1492                 return res;
1493
1494         /*
1495          * If a journal handle was specified, then the encryption context is
1496          * being set on a new inode via inheritance and is part of a larger
1497          * transaction to create the inode.  Otherwise the encryption context is
1498          * being set on an existing inode in its own transaction.  Only in the
1499          * latter case should the "retry on ENOSPC" logic be used.
1500          */
1501
1502         if (handle) {
1503                 res = ext4_xattr_set_handle(handle, inode,
1504                                             EXT4_XATTR_INDEX_ENCRYPTION,
1505                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1506                                             ctx, len, 0);
1507                 if (!res) {
1508                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1509                         ext4_clear_inode_state(inode,
1510                                         EXT4_STATE_MAY_INLINE_DATA);
1511                         /*
1512                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1513                          * S_DAX may be disabled
1514                          */
1515                         ext4_set_inode_flags(inode, false);
1516                 }
1517                 return res;
1518         }
1519
1520         res = dquot_initialize(inode);
1521         if (res)
1522                 return res;
1523 retry:
1524         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1525                                      &credits);
1526         if (res)
1527                 return res;
1528
1529         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1530         if (IS_ERR(handle))
1531                 return PTR_ERR(handle);
1532
1533         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1534                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1535                                     ctx, len, 0);
1536         if (!res) {
1537                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1538                 /*
1539                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1540                  * S_DAX may be disabled
1541                  */
1542                 ext4_set_inode_flags(inode, false);
1543                 res = ext4_mark_inode_dirty(handle, inode);
1544                 if (res)
1545                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1546         }
1547         res2 = ext4_journal_stop(handle);
1548
1549         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1550                 goto retry;
1551         if (!res)
1552                 res = res2;
1553         return res;
1554 }
1555
1556 static const union fscrypt_policy *ext4_get_dummy_policy(struct super_block *sb)
1557 {
1558         return EXT4_SB(sb)->s_dummy_enc_policy.policy;
1559 }
1560
1561 static bool ext4_has_stable_inodes(struct super_block *sb)
1562 {
1563         return ext4_has_feature_stable_inodes(sb);
1564 }
1565
1566 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1567                                        int *ino_bits_ret, int *lblk_bits_ret)
1568 {
1569         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1570         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1571 }
1572
1573 static const struct fscrypt_operations ext4_cryptops = {
1574         .key_prefix             = "ext4:",
1575         .get_context            = ext4_get_context,
1576         .set_context            = ext4_set_context,
1577         .get_dummy_policy       = ext4_get_dummy_policy,
1578         .empty_dir              = ext4_empty_dir,
1579         .max_namelen            = EXT4_NAME_LEN,
1580         .has_stable_inodes      = ext4_has_stable_inodes,
1581         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1582 };
1583 #endif
1584
1585 #ifdef CONFIG_QUOTA
1586 static const char * const quotatypes[] = INITQFNAMES;
1587 #define QTYPE2NAME(t) (quotatypes[t])
1588
1589 static int ext4_write_dquot(struct dquot *dquot);
1590 static int ext4_acquire_dquot(struct dquot *dquot);
1591 static int ext4_release_dquot(struct dquot *dquot);
1592 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1593 static int ext4_write_info(struct super_block *sb, int type);
1594 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1595                          const struct path *path);
1596 static int ext4_quota_on_mount(struct super_block *sb, int type);
1597 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1598                                size_t len, loff_t off);
1599 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1600                                 const char *data, size_t len, loff_t off);
1601 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1602                              unsigned int flags);
1603 static int ext4_enable_quotas(struct super_block *sb);
1604
1605 static struct dquot **ext4_get_dquots(struct inode *inode)
1606 {
1607         return EXT4_I(inode)->i_dquot;
1608 }
1609
1610 static const struct dquot_operations ext4_quota_operations = {
1611         .get_reserved_space     = ext4_get_reserved_space,
1612         .write_dquot            = ext4_write_dquot,
1613         .acquire_dquot          = ext4_acquire_dquot,
1614         .release_dquot          = ext4_release_dquot,
1615         .mark_dirty             = ext4_mark_dquot_dirty,
1616         .write_info             = ext4_write_info,
1617         .alloc_dquot            = dquot_alloc,
1618         .destroy_dquot          = dquot_destroy,
1619         .get_projid             = ext4_get_projid,
1620         .get_inode_usage        = ext4_get_inode_usage,
1621         .get_next_id            = dquot_get_next_id,
1622 };
1623
1624 static const struct quotactl_ops ext4_qctl_operations = {
1625         .quota_on       = ext4_quota_on,
1626         .quota_off      = ext4_quota_off,
1627         .quota_sync     = dquot_quota_sync,
1628         .get_state      = dquot_get_state,
1629         .set_info       = dquot_set_dqinfo,
1630         .get_dqblk      = dquot_get_dqblk,
1631         .set_dqblk      = dquot_set_dqblk,
1632         .get_nextdqblk  = dquot_get_next_dqblk,
1633 };
1634 #endif
1635
1636 static const struct super_operations ext4_sops = {
1637         .alloc_inode    = ext4_alloc_inode,
1638         .free_inode     = ext4_free_in_core_inode,
1639         .destroy_inode  = ext4_destroy_inode,
1640         .write_inode    = ext4_write_inode,
1641         .dirty_inode    = ext4_dirty_inode,
1642         .drop_inode     = ext4_drop_inode,
1643         .evict_inode    = ext4_evict_inode,
1644         .put_super      = ext4_put_super,
1645         .sync_fs        = ext4_sync_fs,
1646         .freeze_fs      = ext4_freeze,
1647         .unfreeze_fs    = ext4_unfreeze,
1648         .statfs         = ext4_statfs,
1649         .remount_fs     = ext4_remount,
1650         .show_options   = ext4_show_options,
1651 #ifdef CONFIG_QUOTA
1652         .quota_read     = ext4_quota_read,
1653         .quota_write    = ext4_quota_write,
1654         .get_dquots     = ext4_get_dquots,
1655 #endif
1656         .bdev_try_to_free_page = bdev_try_to_free_page,
1657 };
1658
1659 static const struct export_operations ext4_export_ops = {
1660         .fh_to_dentry = ext4_fh_to_dentry,
1661         .fh_to_parent = ext4_fh_to_parent,
1662         .get_parent = ext4_get_parent,
1663         .commit_metadata = ext4_nfs_commit_metadata,
1664 };
1665
1666 enum {
1667         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1668         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1669         Opt_nouid32, Opt_debug, Opt_removed,
1670         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1671         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1672         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1673         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1674         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1675         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1676         Opt_inlinecrypt,
1677         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1678         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1679         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1680         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
1681         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1682         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1683         Opt_nowarn_on_error, Opt_mblk_io_submit,
1684         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1685         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1686         Opt_inode_readahead_blks, Opt_journal_ioprio,
1687         Opt_dioread_nolock, Opt_dioread_lock,
1688         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1689         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1690         Opt_prefetch_block_bitmaps,
1691 #ifdef CONFIG_EXT4_DEBUG
1692         Opt_fc_debug_max_replay, Opt_fc_debug_force
1693 #endif
1694 };
1695
1696 static const match_table_t tokens = {
1697         {Opt_bsd_df, "bsddf"},
1698         {Opt_minix_df, "minixdf"},
1699         {Opt_grpid, "grpid"},
1700         {Opt_grpid, "bsdgroups"},
1701         {Opt_nogrpid, "nogrpid"},
1702         {Opt_nogrpid, "sysvgroups"},
1703         {Opt_resgid, "resgid=%u"},
1704         {Opt_resuid, "resuid=%u"},
1705         {Opt_sb, "sb=%u"},
1706         {Opt_err_cont, "errors=continue"},
1707         {Opt_err_panic, "errors=panic"},
1708         {Opt_err_ro, "errors=remount-ro"},
1709         {Opt_nouid32, "nouid32"},
1710         {Opt_debug, "debug"},
1711         {Opt_removed, "oldalloc"},
1712         {Opt_removed, "orlov"},
1713         {Opt_user_xattr, "user_xattr"},
1714         {Opt_nouser_xattr, "nouser_xattr"},
1715         {Opt_acl, "acl"},
1716         {Opt_noacl, "noacl"},
1717         {Opt_noload, "norecovery"},
1718         {Opt_noload, "noload"},
1719         {Opt_removed, "nobh"},
1720         {Opt_removed, "bh"},
1721         {Opt_commit, "commit=%u"},
1722         {Opt_min_batch_time, "min_batch_time=%u"},
1723         {Opt_max_batch_time, "max_batch_time=%u"},
1724         {Opt_journal_dev, "journal_dev=%u"},
1725         {Opt_journal_path, "journal_path=%s"},
1726         {Opt_journal_checksum, "journal_checksum"},
1727         {Opt_nojournal_checksum, "nojournal_checksum"},
1728         {Opt_journal_async_commit, "journal_async_commit"},
1729         {Opt_abort, "abort"},
1730         {Opt_data_journal, "data=journal"},
1731         {Opt_data_ordered, "data=ordered"},
1732         {Opt_data_writeback, "data=writeback"},
1733         {Opt_data_err_abort, "data_err=abort"},
1734         {Opt_data_err_ignore, "data_err=ignore"},
1735         {Opt_offusrjquota, "usrjquota="},
1736         {Opt_usrjquota, "usrjquota=%s"},
1737         {Opt_offgrpjquota, "grpjquota="},
1738         {Opt_grpjquota, "grpjquota=%s"},
1739         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1740         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1741         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1742         {Opt_grpquota, "grpquota"},
1743         {Opt_noquota, "noquota"},
1744         {Opt_quota, "quota"},
1745         {Opt_usrquota, "usrquota"},
1746         {Opt_prjquota, "prjquota"},
1747         {Opt_barrier, "barrier=%u"},
1748         {Opt_barrier, "barrier"},
1749         {Opt_nobarrier, "nobarrier"},
1750         {Opt_i_version, "i_version"},
1751         {Opt_dax, "dax"},
1752         {Opt_dax_always, "dax=always"},
1753         {Opt_dax_inode, "dax=inode"},
1754         {Opt_dax_never, "dax=never"},
1755         {Opt_stripe, "stripe=%u"},
1756         {Opt_delalloc, "delalloc"},
1757         {Opt_warn_on_error, "warn_on_error"},
1758         {Opt_nowarn_on_error, "nowarn_on_error"},
1759         {Opt_lazytime, "lazytime"},
1760         {Opt_nolazytime, "nolazytime"},
1761         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1762         {Opt_nodelalloc, "nodelalloc"},
1763         {Opt_removed, "mblk_io_submit"},
1764         {Opt_removed, "nomblk_io_submit"},
1765         {Opt_block_validity, "block_validity"},
1766         {Opt_noblock_validity, "noblock_validity"},
1767         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1768         {Opt_journal_ioprio, "journal_ioprio=%u"},
1769         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1770         {Opt_auto_da_alloc, "auto_da_alloc"},
1771         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1772         {Opt_dioread_nolock, "dioread_nolock"},
1773         {Opt_dioread_lock, "nodioread_nolock"},
1774         {Opt_dioread_lock, "dioread_lock"},
1775         {Opt_discard, "discard"},
1776         {Opt_nodiscard, "nodiscard"},
1777         {Opt_init_itable, "init_itable=%u"},
1778         {Opt_init_itable, "init_itable"},
1779         {Opt_noinit_itable, "noinit_itable"},
1780 #ifdef CONFIG_EXT4_DEBUG
1781         {Opt_fc_debug_force, "fc_debug_force"},
1782         {Opt_fc_debug_max_replay, "fc_debug_max_replay=%u"},
1783 #endif
1784         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1785         {Opt_test_dummy_encryption, "test_dummy_encryption=%s"},
1786         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1787         {Opt_inlinecrypt, "inlinecrypt"},
1788         {Opt_nombcache, "nombcache"},
1789         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1790         {Opt_prefetch_block_bitmaps, "prefetch_block_bitmaps"},
1791         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1792         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1793         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1794         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1795         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1796         {Opt_err, NULL},
1797 };
1798
1799 static ext4_fsblk_t get_sb_block(void **data)
1800 {
1801         ext4_fsblk_t    sb_block;
1802         char            *options = (char *) *data;
1803
1804         if (!options || strncmp(options, "sb=", 3) != 0)
1805                 return 1;       /* Default location */
1806
1807         options += 3;
1808         /* TODO: use simple_strtoll with >32bit ext4 */
1809         sb_block = simple_strtoul(options, &options, 0);
1810         if (*options && *options != ',') {
1811                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1812                        (char *) *data);
1813                 return 1;
1814         }
1815         if (*options == ',')
1816                 options++;
1817         *data = (void *) options;
1818
1819         return sb_block;
1820 }
1821
1822 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1823 static const char deprecated_msg[] =
1824         "Mount option \"%s\" will be removed by %s\n"
1825         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1826
1827 #ifdef CONFIG_QUOTA
1828 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1829 {
1830         struct ext4_sb_info *sbi = EXT4_SB(sb);
1831         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1832         int ret = -1;
1833
1834         if (sb_any_quota_loaded(sb) && !old_qname) {
1835                 ext4_msg(sb, KERN_ERR,
1836                         "Cannot change journaled "
1837                         "quota options when quota turned on");
1838                 return -1;
1839         }
1840         if (ext4_has_feature_quota(sb)) {
1841                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1842                          "ignored when QUOTA feature is enabled");
1843                 return 1;
1844         }
1845         qname = match_strdup(args);
1846         if (!qname) {
1847                 ext4_msg(sb, KERN_ERR,
1848                         "Not enough memory for storing quotafile name");
1849                 return -1;
1850         }
1851         if (old_qname) {
1852                 if (strcmp(old_qname, qname) == 0)
1853                         ret = 1;
1854                 else
1855                         ext4_msg(sb, KERN_ERR,
1856                                  "%s quota file already specified",
1857                                  QTYPE2NAME(qtype));
1858                 goto errout;
1859         }
1860         if (strchr(qname, '/')) {
1861                 ext4_msg(sb, KERN_ERR,
1862                         "quotafile must be on filesystem root");
1863                 goto errout;
1864         }
1865         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1866         set_opt(sb, QUOTA);
1867         return 1;
1868 errout:
1869         kfree(qname);
1870         return ret;
1871 }
1872
1873 static int clear_qf_name(struct super_block *sb, int qtype)
1874 {
1875
1876         struct ext4_sb_info *sbi = EXT4_SB(sb);
1877         char *old_qname = get_qf_name(sb, sbi, qtype);
1878
1879         if (sb_any_quota_loaded(sb) && old_qname) {
1880                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1881                         " when quota turned on");
1882                 return -1;
1883         }
1884         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1885         synchronize_rcu();
1886         kfree(old_qname);
1887         return 1;
1888 }
1889 #endif
1890
1891 #define MOPT_SET        0x0001
1892 #define MOPT_CLEAR      0x0002
1893 #define MOPT_NOSUPPORT  0x0004
1894 #define MOPT_EXPLICIT   0x0008
1895 #define MOPT_CLEAR_ERR  0x0010
1896 #define MOPT_GTE0       0x0020
1897 #ifdef CONFIG_QUOTA
1898 #define MOPT_Q          0
1899 #define MOPT_QFMT       0x0040
1900 #else
1901 #define MOPT_Q          MOPT_NOSUPPORT
1902 #define MOPT_QFMT       MOPT_NOSUPPORT
1903 #endif
1904 #define MOPT_DATAJ      0x0080
1905 #define MOPT_NO_EXT2    0x0100
1906 #define MOPT_NO_EXT3    0x0200
1907 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1908 #define MOPT_STRING     0x0400
1909 #define MOPT_SKIP       0x0800
1910 #define MOPT_2          0x1000
1911
1912 static const struct mount_opts {
1913         int     token;
1914         int     mount_opt;
1915         int     flags;
1916 } ext4_mount_opts[] = {
1917         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1918         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1919         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1920         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1921         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1922         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1923         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1924          MOPT_EXT4_ONLY | MOPT_SET},
1925         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1926          MOPT_EXT4_ONLY | MOPT_CLEAR},
1927         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1928         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1929         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1930          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1931         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1932          MOPT_EXT4_ONLY | MOPT_CLEAR},
1933         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1934         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1935         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1936          MOPT_EXT4_ONLY | MOPT_CLEAR},
1937         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1938          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1939         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1940                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1941          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1942         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1943         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1944         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1945         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1946         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1947          MOPT_NO_EXT2},
1948         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1949          MOPT_NO_EXT2},
1950         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1951         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1952         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1953         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1954         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1955         {Opt_commit, 0, MOPT_GTE0},
1956         {Opt_max_batch_time, 0, MOPT_GTE0},
1957         {Opt_min_batch_time, 0, MOPT_GTE0},
1958         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1959         {Opt_init_itable, 0, MOPT_GTE0},
1960         {Opt_dax, EXT4_MOUNT_DAX_ALWAYS, MOPT_SET | MOPT_SKIP},
1961         {Opt_dax_always, EXT4_MOUNT_DAX_ALWAYS,
1962                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1963         {Opt_dax_inode, EXT4_MOUNT2_DAX_INODE,
1964                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1965         {Opt_dax_never, EXT4_MOUNT2_DAX_NEVER,
1966                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1967         {Opt_stripe, 0, MOPT_GTE0},
1968         {Opt_resuid, 0, MOPT_GTE0},
1969         {Opt_resgid, 0, MOPT_GTE0},
1970         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1971         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1972         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1973         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1974         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1975         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1976          MOPT_NO_EXT2 | MOPT_DATAJ},
1977         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1978         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1979 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1980         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1981         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1982 #else
1983         {Opt_acl, 0, MOPT_NOSUPPORT},
1984         {Opt_noacl, 0, MOPT_NOSUPPORT},
1985 #endif
1986         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1987         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1988         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1989         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1990         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1991                                                         MOPT_SET | MOPT_Q},
1992         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1993                                                         MOPT_SET | MOPT_Q},
1994         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1995                                                         MOPT_SET | MOPT_Q},
1996         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1997                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1998                                                         MOPT_CLEAR | MOPT_Q},
1999         {Opt_usrjquota, 0, MOPT_Q | MOPT_STRING},
2000         {Opt_grpjquota, 0, MOPT_Q | MOPT_STRING},
2001         {Opt_offusrjquota, 0, MOPT_Q},
2002         {Opt_offgrpjquota, 0, MOPT_Q},
2003         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
2004         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
2005         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
2006         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
2007         {Opt_test_dummy_encryption, 0, MOPT_STRING},
2008         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
2009         {Opt_prefetch_block_bitmaps, EXT4_MOUNT_PREFETCH_BLOCK_BITMAPS,
2010          MOPT_SET},
2011 #ifdef CONFIG_EXT4_DEBUG
2012         {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
2013          MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
2014         {Opt_fc_debug_max_replay, 0, MOPT_GTE0},
2015 #endif
2016         {Opt_err, 0, 0}
2017 };
2018
2019 #ifdef CONFIG_UNICODE
2020 static const struct ext4_sb_encodings {
2021         __u16 magic;
2022         char *name;
2023         char *version;
2024 } ext4_sb_encoding_map[] = {
2025         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
2026 };
2027
2028 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
2029                                  const struct ext4_sb_encodings **encoding,
2030                                  __u16 *flags)
2031 {
2032         __u16 magic = le16_to_cpu(es->s_encoding);
2033         int i;
2034
2035         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
2036                 if (magic == ext4_sb_encoding_map[i].magic)
2037                         break;
2038
2039         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
2040                 return -EINVAL;
2041
2042         *encoding = &ext4_sb_encoding_map[i];
2043         *flags = le16_to_cpu(es->s_encoding_flags);
2044
2045         return 0;
2046 }
2047 #endif
2048
2049 static int ext4_set_test_dummy_encryption(struct super_block *sb,
2050                                           const char *opt,
2051                                           const substring_t *arg,
2052                                           bool is_remount)
2053 {
2054 #ifdef CONFIG_FS_ENCRYPTION
2055         struct ext4_sb_info *sbi = EXT4_SB(sb);
2056         int err;
2057
2058         /*
2059          * This mount option is just for testing, and it's not worthwhile to
2060          * implement the extra complexity (e.g. RCU protection) that would be
2061          * needed to allow it to be set or changed during remount.  We do allow
2062          * it to be specified during remount, but only if there is no change.
2063          */
2064         if (is_remount && !sbi->s_dummy_enc_policy.policy) {
2065                 ext4_msg(sb, KERN_WARNING,
2066                          "Can't set test_dummy_encryption on remount");
2067                 return -1;
2068         }
2069         err = fscrypt_set_test_dummy_encryption(sb, arg->from,
2070                                                 &sbi->s_dummy_enc_policy);
2071         if (err) {
2072                 if (err == -EEXIST)
2073                         ext4_msg(sb, KERN_WARNING,
2074                                  "Can't change test_dummy_encryption on remount");
2075                 else if (err == -EINVAL)
2076                         ext4_msg(sb, KERN_WARNING,
2077                                  "Value of option \"%s\" is unrecognized", opt);
2078                 else
2079                         ext4_msg(sb, KERN_WARNING,
2080                                  "Error processing option \"%s\" [%d]",
2081                                  opt, err);
2082                 return -1;
2083         }
2084         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2085 #else
2086         ext4_msg(sb, KERN_WARNING,
2087                  "Test dummy encryption mount option ignored");
2088 #endif
2089         return 1;
2090 }
2091
2092 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
2093                             substring_t *args, unsigned long *journal_devnum,
2094                             unsigned int *journal_ioprio, int is_remount)
2095 {
2096         struct ext4_sb_info *sbi = EXT4_SB(sb);
2097         const struct mount_opts *m;
2098         kuid_t uid;
2099         kgid_t gid;
2100         int arg = 0;
2101
2102 #ifdef CONFIG_QUOTA
2103         if (token == Opt_usrjquota)
2104                 return set_qf_name(sb, USRQUOTA, &args[0]);
2105         else if (token == Opt_grpjquota)
2106                 return set_qf_name(sb, GRPQUOTA, &args[0]);
2107         else if (token == Opt_offusrjquota)
2108                 return clear_qf_name(sb, USRQUOTA);
2109         else if (token == Opt_offgrpjquota)
2110                 return clear_qf_name(sb, GRPQUOTA);
2111 #endif
2112         switch (token) {
2113         case Opt_noacl:
2114         case Opt_nouser_xattr:
2115                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
2116                 break;
2117         case Opt_sb:
2118                 return 1;       /* handled by get_sb_block() */
2119         case Opt_removed:
2120                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
2121                 return 1;
2122         case Opt_abort:
2123                 ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
2124                 return 1;
2125         case Opt_i_version:
2126                 sb->s_flags |= SB_I_VERSION;
2127                 return 1;
2128         case Opt_lazytime:
2129                 sb->s_flags |= SB_LAZYTIME;
2130                 return 1;
2131         case Opt_nolazytime:
2132                 sb->s_flags &= ~SB_LAZYTIME;
2133                 return 1;
2134         case Opt_inlinecrypt:
2135 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2136                 sb->s_flags |= SB_INLINECRYPT;
2137 #else
2138                 ext4_msg(sb, KERN_ERR, "inline encryption not supported");
2139 #endif
2140                 return 1;
2141         }
2142
2143         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2144                 if (token == m->token)
2145                         break;
2146
2147         if (m->token == Opt_err) {
2148                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
2149                          "or missing value", opt);
2150                 return -1;
2151         }
2152
2153         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2154                 ext4_msg(sb, KERN_ERR,
2155                          "Mount option \"%s\" incompatible with ext2", opt);
2156                 return -1;
2157         }
2158         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2159                 ext4_msg(sb, KERN_ERR,
2160                          "Mount option \"%s\" incompatible with ext3", opt);
2161                 return -1;
2162         }
2163
2164         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
2165                 return -1;
2166         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
2167                 return -1;
2168         if (m->flags & MOPT_EXPLICIT) {
2169                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2170                         set_opt2(sb, EXPLICIT_DELALLOC);
2171                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2172                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
2173                 } else
2174                         return -1;
2175         }
2176         if (m->flags & MOPT_CLEAR_ERR)
2177                 clear_opt(sb, ERRORS_MASK);
2178         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
2179                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
2180                          "options when quota turned on");
2181                 return -1;
2182         }
2183
2184         if (m->flags & MOPT_NOSUPPORT) {
2185                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
2186         } else if (token == Opt_commit) {
2187                 if (arg == 0)
2188                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
2189                 else if (arg > INT_MAX / HZ) {
2190                         ext4_msg(sb, KERN_ERR,
2191                                  "Invalid commit interval %d, "
2192                                  "must be smaller than %d",
2193                                  arg, INT_MAX / HZ);
2194                         return -1;
2195                 }
2196                 sbi->s_commit_interval = HZ * arg;
2197         } else if (token == Opt_debug_want_extra_isize) {
2198                 if ((arg & 1) ||
2199                     (arg < 4) ||
2200                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
2201                         ext4_msg(sb, KERN_ERR,
2202                                  "Invalid want_extra_isize %d", arg);
2203                         return -1;
2204                 }
2205                 sbi->s_want_extra_isize = arg;
2206         } else if (token == Opt_max_batch_time) {
2207                 sbi->s_max_batch_time = arg;
2208         } else if (token == Opt_min_batch_time) {
2209                 sbi->s_min_batch_time = arg;
2210         } else if (token == Opt_inode_readahead_blks) {
2211                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
2212                         ext4_msg(sb, KERN_ERR,
2213                                  "EXT4-fs: inode_readahead_blks must be "
2214                                  "0 or a power of 2 smaller than 2^31");
2215                         return -1;
2216                 }
2217                 sbi->s_inode_readahead_blks = arg;
2218         } else if (token == Opt_init_itable) {
2219                 set_opt(sb, INIT_INODE_TABLE);
2220                 if (!args->from)
2221                         arg = EXT4_DEF_LI_WAIT_MULT;
2222                 sbi->s_li_wait_mult = arg;
2223         } else if (token == Opt_max_dir_size_kb) {
2224                 sbi->s_max_dir_size_kb = arg;
2225 #ifdef CONFIG_EXT4_DEBUG
2226         } else if (token == Opt_fc_debug_max_replay) {
2227                 sbi->s_fc_debug_max_replay = arg;
2228 #endif
2229         } else if (token == Opt_stripe) {
2230                 sbi->s_stripe = arg;
2231         } else if (token == Opt_resuid) {
2232                 uid = make_kuid(current_user_ns(), arg);
2233                 if (!uid_valid(uid)) {
2234                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
2235                         return -1;
2236                 }
2237                 sbi->s_resuid = uid;
2238         } else if (token == Opt_resgid) {
2239                 gid = make_kgid(current_user_ns(), arg);
2240                 if (!gid_valid(gid)) {
2241                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
2242                         return -1;
2243                 }
2244                 sbi->s_resgid = gid;
2245         } else if (token == Opt_journal_dev) {
2246                 if (is_remount) {
2247                         ext4_msg(sb, KERN_ERR,
2248                                  "Cannot specify journal on remount");
2249                         return -1;
2250                 }
2251                 *journal_devnum = arg;
2252         } else if (token == Opt_journal_path) {
2253                 char *journal_path;
2254                 struct inode *journal_inode;
2255                 struct path path;
2256                 int error;
2257
2258                 if (is_remount) {
2259                         ext4_msg(sb, KERN_ERR,
2260                                  "Cannot specify journal on remount");
2261                         return -1;
2262                 }
2263                 journal_path = match_strdup(&args[0]);
2264                 if (!journal_path) {
2265                         ext4_msg(sb, KERN_ERR, "error: could not dup "
2266                                 "journal device string");
2267                         return -1;
2268                 }
2269
2270                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2271                 if (error) {
2272                         ext4_msg(sb, KERN_ERR, "error: could not find "
2273                                 "journal device path: error %d", error);
2274                         kfree(journal_path);
2275                         return -1;
2276                 }
2277
2278                 journal_inode = d_inode(path.dentry);
2279                 if (!S_ISBLK(journal_inode->i_mode)) {
2280                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
2281                                 "is not a block device", journal_path);
2282                         path_put(&path);
2283                         kfree(journal_path);
2284                         return -1;
2285                 }
2286
2287                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
2288                 path_put(&path);
2289                 kfree(journal_path);
2290         } else if (token == Opt_journal_ioprio) {
2291                 if (arg > 7) {
2292                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2293                                  " (must be 0-7)");
2294                         return -1;
2295                 }
2296                 *journal_ioprio =
2297                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2298         } else if (token == Opt_test_dummy_encryption) {
2299                 return ext4_set_test_dummy_encryption(sb, opt, &args[0],
2300                                                       is_remount);
2301         } else if (m->flags & MOPT_DATAJ) {
2302                 if (is_remount) {
2303                         if (!sbi->s_journal)
2304                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2305                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2306                                 ext4_msg(sb, KERN_ERR,
2307                                          "Cannot change data mode on remount");
2308                                 return -1;
2309                         }
2310                 } else {
2311                         clear_opt(sb, DATA_FLAGS);
2312                         sbi->s_mount_opt |= m->mount_opt;
2313                 }
2314 #ifdef CONFIG_QUOTA
2315         } else if (m->flags & MOPT_QFMT) {
2316                 if (sb_any_quota_loaded(sb) &&
2317                     sbi->s_jquota_fmt != m->mount_opt) {
2318                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2319                                  "quota options when quota turned on");
2320                         return -1;
2321                 }
2322                 if (ext4_has_feature_quota(sb)) {
2323                         ext4_msg(sb, KERN_INFO,
2324                                  "Quota format mount options ignored "
2325                                  "when QUOTA feature is enabled");
2326                         return 1;
2327                 }
2328                 sbi->s_jquota_fmt = m->mount_opt;
2329 #endif
2330         } else if (token == Opt_dax || token == Opt_dax_always ||
2331                    token == Opt_dax_inode || token == Opt_dax_never) {
2332 #ifdef CONFIG_FS_DAX
2333                 switch (token) {
2334                 case Opt_dax:
2335                 case Opt_dax_always:
2336                         if (is_remount &&
2337                             (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2338                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2339                         fail_dax_change_remount:
2340                                 ext4_msg(sb, KERN_ERR, "can't change "
2341                                          "dax mount option while remounting");
2342                                 return -1;
2343                         }
2344                         if (is_remount &&
2345                             (test_opt(sb, DATA_FLAGS) ==
2346                              EXT4_MOUNT_JOURNAL_DATA)) {
2347                                     ext4_msg(sb, KERN_ERR, "can't mount with "
2348                                              "both data=journal and dax");
2349                                     return -1;
2350                         }
2351                         ext4_msg(sb, KERN_WARNING,
2352                                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2353                         sbi->s_mount_opt |= EXT4_MOUNT_DAX_ALWAYS;
2354                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2355                         break;
2356                 case Opt_dax_never:
2357                         if (is_remount &&
2358                             (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2359                              (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS)))
2360                                 goto fail_dax_change_remount;
2361                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2362                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2363                         break;
2364                 case Opt_dax_inode:
2365                         if (is_remount &&
2366                             ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2367                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2368                              !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE)))
2369                                 goto fail_dax_change_remount;
2370                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2371                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2372                         /* Strictly for printing options */
2373                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_INODE;
2374                         break;
2375                 }
2376 #else
2377                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2378                 sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2379                 sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2380                 return -1;
2381 #endif
2382         } else if (token == Opt_data_err_abort) {
2383                 sbi->s_mount_opt |= m->mount_opt;
2384         } else if (token == Opt_data_err_ignore) {
2385                 sbi->s_mount_opt &= ~m->mount_opt;
2386         } else {
2387                 if (!args->from)
2388                         arg = 1;
2389                 if (m->flags & MOPT_CLEAR)
2390                         arg = !arg;
2391                 else if (unlikely(!(m->flags & MOPT_SET))) {
2392                         ext4_msg(sb, KERN_WARNING,
2393                                  "buggy handling of option %s", opt);
2394                         WARN_ON(1);
2395                         return -1;
2396                 }
2397                 if (m->flags & MOPT_2) {
2398                         if (arg != 0)
2399                                 sbi->s_mount_opt2 |= m->mount_opt;
2400                         else
2401                                 sbi->s_mount_opt2 &= ~m->mount_opt;
2402                 } else {
2403                         if (arg != 0)
2404                                 sbi->s_mount_opt |= m->mount_opt;
2405                         else
2406                                 sbi->s_mount_opt &= ~m->mount_opt;
2407                 }
2408         }
2409         return 1;
2410 }
2411
2412 static int parse_options(char *options, struct super_block *sb,
2413                          unsigned long *journal_devnum,
2414                          unsigned int *journal_ioprio,
2415                          int is_remount)
2416 {
2417         struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2418         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2419         substring_t args[MAX_OPT_ARGS];
2420         int token;
2421
2422         if (!options)
2423                 return 1;
2424
2425         while ((p = strsep(&options, ",")) != NULL) {
2426                 if (!*p)
2427                         continue;
2428                 /*
2429                  * Initialize args struct so we know whether arg was
2430                  * found; some options take optional arguments.
2431                  */
2432                 args[0].to = args[0].from = NULL;
2433                 token = match_token(p, tokens, args);
2434                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2435                                      journal_ioprio, is_remount) < 0)
2436                         return 0;
2437         }
2438 #ifdef CONFIG_QUOTA
2439         /*
2440          * We do the test below only for project quotas. 'usrquota' and
2441          * 'grpquota' mount options are allowed even without quota feature
2442          * to support legacy quotas in quota files.
2443          */
2444         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2445                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2446                          "Cannot enable project quota enforcement.");
2447                 return 0;
2448         }
2449         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2450         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2451         if (usr_qf_name || grp_qf_name) {
2452                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2453                         clear_opt(sb, USRQUOTA);
2454
2455                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2456                         clear_opt(sb, GRPQUOTA);
2457
2458                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2459                         ext4_msg(sb, KERN_ERR, "old and new quota "
2460                                         "format mixing");
2461                         return 0;
2462                 }
2463
2464                 if (!sbi->s_jquota_fmt) {
2465                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2466                                         "not specified");
2467                         return 0;
2468                 }
2469         }
2470 #endif
2471         if (test_opt(sb, DIOREAD_NOLOCK)) {
2472                 int blocksize =
2473                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2474                 if (blocksize < PAGE_SIZE)
2475                         ext4_msg(sb, KERN_WARNING, "Warning: mounting with an "
2476                                  "experimental mount option 'dioread_nolock' "
2477                                  "for blocksize < PAGE_SIZE");
2478         }
2479         return 1;
2480 }
2481
2482 static inline void ext4_show_quota_options(struct seq_file *seq,
2483                                            struct super_block *sb)
2484 {
2485 #if defined(CONFIG_QUOTA)
2486         struct ext4_sb_info *sbi = EXT4_SB(sb);
2487         char *usr_qf_name, *grp_qf_name;
2488
2489         if (sbi->s_jquota_fmt) {
2490                 char *fmtname = "";
2491
2492                 switch (sbi->s_jquota_fmt) {
2493                 case QFMT_VFS_OLD:
2494                         fmtname = "vfsold";
2495                         break;
2496                 case QFMT_VFS_V0:
2497                         fmtname = "vfsv0";
2498                         break;
2499                 case QFMT_VFS_V1:
2500                         fmtname = "vfsv1";
2501                         break;
2502                 }
2503                 seq_printf(seq, ",jqfmt=%s", fmtname);
2504         }
2505
2506         rcu_read_lock();
2507         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2508         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2509         if (usr_qf_name)
2510                 seq_show_option(seq, "usrjquota", usr_qf_name);
2511         if (grp_qf_name)
2512                 seq_show_option(seq, "grpjquota", grp_qf_name);
2513         rcu_read_unlock();
2514 #endif
2515 }
2516
2517 static const char *token2str(int token)
2518 {
2519         const struct match_token *t;
2520
2521         for (t = tokens; t->token != Opt_err; t++)
2522                 if (t->token == token && !strchr(t->pattern, '='))
2523                         break;
2524         return t->pattern;
2525 }
2526
2527 /*
2528  * Show an option if
2529  *  - it's set to a non-default value OR
2530  *  - if the per-sb default is different from the global default
2531  */
2532 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2533                               int nodefs)
2534 {
2535         struct ext4_sb_info *sbi = EXT4_SB(sb);
2536         struct ext4_super_block *es = sbi->s_es;
2537         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2538         const struct mount_opts *m;
2539         char sep = nodefs ? '\n' : ',';
2540
2541 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2542 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2543
2544         if (sbi->s_sb_block != 1)
2545                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2546
2547         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2548                 int want_set = m->flags & MOPT_SET;
2549                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2550                     (m->flags & MOPT_CLEAR_ERR) || m->flags & MOPT_SKIP)
2551                         continue;
2552                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2553                         continue; /* skip if same as the default */
2554                 if ((want_set &&
2555                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2556                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2557                         continue; /* select Opt_noFoo vs Opt_Foo */
2558                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2559         }
2560
2561         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2562             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2563                 SEQ_OPTS_PRINT("resuid=%u",
2564                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2565         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2566             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2567                 SEQ_OPTS_PRINT("resgid=%u",
2568                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2569         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2570         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2571                 SEQ_OPTS_PUTS("errors=remount-ro");
2572         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2573                 SEQ_OPTS_PUTS("errors=continue");
2574         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2575                 SEQ_OPTS_PUTS("errors=panic");
2576         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2577                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2578         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2579                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2580         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2581                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2582         if (sb->s_flags & SB_I_VERSION)
2583                 SEQ_OPTS_PUTS("i_version");
2584         if (nodefs || sbi->s_stripe)
2585                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2586         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2587                         (sbi->s_mount_opt ^ def_mount_opt)) {
2588                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2589                         SEQ_OPTS_PUTS("data=journal");
2590                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2591                         SEQ_OPTS_PUTS("data=ordered");
2592                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2593                         SEQ_OPTS_PUTS("data=writeback");
2594         }
2595         if (nodefs ||
2596             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2597                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2598                                sbi->s_inode_readahead_blks);
2599
2600         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2601                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2602                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2603         if (nodefs || sbi->s_max_dir_size_kb)
2604                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2605         if (test_opt(sb, DATA_ERR_ABORT))
2606                 SEQ_OPTS_PUTS("data_err=abort");
2607
2608         fscrypt_show_test_dummy_encryption(seq, sep, sb);
2609
2610         if (sb->s_flags & SB_INLINECRYPT)
2611                 SEQ_OPTS_PUTS("inlinecrypt");
2612
2613         if (test_opt(sb, DAX_ALWAYS)) {
2614                 if (IS_EXT2_SB(sb))
2615                         SEQ_OPTS_PUTS("dax");
2616                 else
2617                         SEQ_OPTS_PUTS("dax=always");
2618         } else if (test_opt2(sb, DAX_NEVER)) {
2619                 SEQ_OPTS_PUTS("dax=never");
2620         } else if (test_opt2(sb, DAX_INODE)) {
2621                 SEQ_OPTS_PUTS("dax=inode");
2622         }
2623         ext4_show_quota_options(seq, sb);
2624         return 0;
2625 }
2626
2627 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2628 {
2629         return _ext4_show_options(seq, root->d_sb, 0);
2630 }
2631
2632 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2633 {
2634         struct super_block *sb = seq->private;
2635         int rc;
2636
2637         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2638         rc = _ext4_show_options(seq, sb, 1);
2639         seq_puts(seq, "\n");
2640         return rc;
2641 }
2642
2643 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2644                             int read_only)
2645 {
2646         struct ext4_sb_info *sbi = EXT4_SB(sb);
2647         int err = 0;
2648
2649         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2650                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2651                          "forcing read-only mode");
2652                 err = -EROFS;
2653                 goto done;
2654         }
2655         if (read_only)
2656                 goto done;
2657         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2658                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2659                          "running e2fsck is recommended");
2660         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2661                 ext4_msg(sb, KERN_WARNING,
2662                          "warning: mounting fs with errors, "
2663                          "running e2fsck is recommended");
2664         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2665                  le16_to_cpu(es->s_mnt_count) >=
2666                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2667                 ext4_msg(sb, KERN_WARNING,
2668                          "warning: maximal mount count reached, "
2669                          "running e2fsck is recommended");
2670         else if (le32_to_cpu(es->s_checkinterval) &&
2671                  (ext4_get_tstamp(es, s_lastcheck) +
2672                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2673                 ext4_msg(sb, KERN_WARNING,
2674                          "warning: checktime reached, "
2675                          "running e2fsck is recommended");
2676         if (!sbi->s_journal)
2677                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2678         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2679                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2680         le16_add_cpu(&es->s_mnt_count, 1);
2681         ext4_update_tstamp(es, s_mtime);
2682         if (sbi->s_journal)
2683                 ext4_set_feature_journal_needs_recovery(sb);
2684
2685         err = ext4_commit_super(sb);
2686 done:
2687         if (test_opt(sb, DEBUG))
2688                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2689                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2690                         sb->s_blocksize,
2691                         sbi->s_groups_count,
2692                         EXT4_BLOCKS_PER_GROUP(sb),
2693                         EXT4_INODES_PER_GROUP(sb),
2694                         sbi->s_mount_opt, sbi->s_mount_opt2);
2695
2696         cleancache_init_fs(sb);
2697         return err;
2698 }
2699
2700 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2701 {
2702         struct ext4_sb_info *sbi = EXT4_SB(sb);
2703         struct flex_groups **old_groups, **new_groups;
2704         int size, i, j;
2705
2706         if (!sbi->s_log_groups_per_flex)
2707                 return 0;
2708
2709         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2710         if (size <= sbi->s_flex_groups_allocated)
2711                 return 0;
2712
2713         new_groups = kvzalloc(roundup_pow_of_two(size *
2714                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2715         if (!new_groups) {
2716                 ext4_msg(sb, KERN_ERR,
2717                          "not enough memory for %d flex group pointers", size);
2718                 return -ENOMEM;
2719         }
2720         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2721                 new_groups[i] = kvzalloc(roundup_pow_of_two(
2722                                          sizeof(struct flex_groups)),
2723                                          GFP_KERNEL);
2724                 if (!new_groups[i]) {
2725                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
2726                                 kvfree(new_groups[j]);
2727                         kvfree(new_groups);
2728                         ext4_msg(sb, KERN_ERR,
2729                                  "not enough memory for %d flex groups", size);
2730                         return -ENOMEM;
2731                 }
2732         }
2733         rcu_read_lock();
2734         old_groups = rcu_dereference(sbi->s_flex_groups);
2735         if (old_groups)
2736                 memcpy(new_groups, old_groups,
2737                        (sbi->s_flex_groups_allocated *
2738                         sizeof(struct flex_groups *)));
2739         rcu_read_unlock();
2740         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2741         sbi->s_flex_groups_allocated = size;
2742         if (old_groups)
2743                 ext4_kvfree_array_rcu(old_groups);
2744         return 0;
2745 }
2746
2747 static int ext4_fill_flex_info(struct super_block *sb)
2748 {
2749         struct ext4_sb_info *sbi = EXT4_SB(sb);
2750         struct ext4_group_desc *gdp = NULL;
2751         struct flex_groups *fg;
2752         ext4_group_t flex_group;
2753         int i, err;
2754
2755         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2756         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2757                 sbi->s_log_groups_per_flex = 0;
2758                 return 1;
2759         }
2760
2761         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2762         if (err)
2763                 goto failed;
2764
2765         for (i = 0; i < sbi->s_groups_count; i++) {
2766                 gdp = ext4_get_group_desc(sb, i, NULL);
2767
2768                 flex_group = ext4_flex_group(sbi, i);
2769                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2770                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2771                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2772                              &fg->free_clusters);
2773                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2774         }
2775
2776         return 1;
2777 failed:
2778         return 0;
2779 }
2780
2781 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2782                                    struct ext4_group_desc *gdp)
2783 {
2784         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2785         __u16 crc = 0;
2786         __le32 le_group = cpu_to_le32(block_group);
2787         struct ext4_sb_info *sbi = EXT4_SB(sb);
2788
2789         if (ext4_has_metadata_csum(sbi->s_sb)) {
2790                 /* Use new metadata_csum algorithm */
2791                 __u32 csum32;
2792                 __u16 dummy_csum = 0;
2793
2794                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2795                                      sizeof(le_group));
2796                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2797                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2798                                      sizeof(dummy_csum));
2799                 offset += sizeof(dummy_csum);
2800                 if (offset < sbi->s_desc_size)
2801                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2802                                              sbi->s_desc_size - offset);
2803
2804                 crc = csum32 & 0xFFFF;
2805                 goto out;
2806         }
2807
2808         /* old crc16 code */
2809         if (!ext4_has_feature_gdt_csum(sb))
2810                 return 0;
2811
2812         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2813         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2814         crc = crc16(crc, (__u8 *)gdp, offset);
2815         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2816         /* for checksum of struct ext4_group_desc do the rest...*/
2817         if (ext4_has_feature_64bit(sb) &&
2818             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2819                 crc = crc16(crc, (__u8 *)gdp + offset,
2820                             le16_to_cpu(sbi->s_es->s_desc_size) -
2821                                 offset);
2822
2823 out:
2824         return cpu_to_le16(crc);
2825 }
2826
2827 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2828                                 struct ext4_group_desc *gdp)
2829 {
2830         if (ext4_has_group_desc_csum(sb) &&
2831             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2832                 return 0;
2833
2834         return 1;
2835 }
2836
2837 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2838                               struct ext4_group_desc *gdp)
2839 {
2840         if (!ext4_has_group_desc_csum(sb))
2841                 return;
2842         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2843 }
2844
2845 /* Called at mount-time, super-block is locked */
2846 static int ext4_check_descriptors(struct super_block *sb,
2847                                   ext4_fsblk_t sb_block,
2848                                   ext4_group_t *first_not_zeroed)
2849 {
2850         struct ext4_sb_info *sbi = EXT4_SB(sb);
2851         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2852         ext4_fsblk_t last_block;
2853         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2854         ext4_fsblk_t block_bitmap;
2855         ext4_fsblk_t inode_bitmap;
2856         ext4_fsblk_t inode_table;
2857         int flexbg_flag = 0;
2858         ext4_group_t i, grp = sbi->s_groups_count;
2859
2860         if (ext4_has_feature_flex_bg(sb))
2861                 flexbg_flag = 1;
2862
2863         ext4_debug("Checking group descriptors");
2864
2865         for (i = 0; i < sbi->s_groups_count; i++) {
2866                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2867
2868                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2869                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2870                 else
2871                         last_block = first_block +
2872                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2873
2874                 if ((grp == sbi->s_groups_count) &&
2875                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2876                         grp = i;
2877
2878                 block_bitmap = ext4_block_bitmap(sb, gdp);
2879                 if (block_bitmap == sb_block) {
2880                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2881                                  "Block bitmap for group %u overlaps "
2882                                  "superblock", i);
2883                         if (!sb_rdonly(sb))
2884                                 return 0;
2885                 }
2886                 if (block_bitmap >= sb_block + 1 &&
2887                     block_bitmap <= last_bg_block) {
2888                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2889                                  "Block bitmap for group %u overlaps "
2890                                  "block group descriptors", i);
2891                         if (!sb_rdonly(sb))
2892                                 return 0;
2893                 }
2894                 if (block_bitmap < first_block || block_bitmap > last_block) {
2895                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2896                                "Block bitmap for group %u not in group "
2897                                "(block %llu)!", i, block_bitmap);
2898                         return 0;
2899                 }
2900                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2901                 if (inode_bitmap == sb_block) {
2902                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2903                                  "Inode bitmap for group %u overlaps "
2904                                  "superblock", i);
2905                         if (!sb_rdonly(sb))
2906                                 return 0;
2907                 }
2908                 if (inode_bitmap >= sb_block + 1 &&
2909                     inode_bitmap <= last_bg_block) {
2910                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2911                                  "Inode bitmap for group %u overlaps "
2912                                  "block group descriptors", i);
2913                         if (!sb_rdonly(sb))
2914                                 return 0;
2915                 }
2916                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2917                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2918                                "Inode bitmap for group %u not in group "
2919                                "(block %llu)!", i, inode_bitmap);
2920                         return 0;
2921                 }
2922                 inode_table = ext4_inode_table(sb, gdp);
2923                 if (inode_table == sb_block) {
2924                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2925                                  "Inode table for group %u overlaps "
2926                                  "superblock", i);
2927                         if (!sb_rdonly(sb))
2928                                 return 0;
2929                 }
2930                 if (inode_table >= sb_block + 1 &&
2931                     inode_table <= last_bg_block) {
2932                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2933                                  "Inode table for group %u overlaps "
2934                                  "block group descriptors", i);
2935                         if (!sb_rdonly(sb))
2936                                 return 0;
2937                 }
2938                 if (inode_table < first_block ||
2939                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2940                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2941                                "Inode table for group %u not in group "
2942                                "(block %llu)!", i, inode_table);
2943                         return 0;
2944                 }
2945                 ext4_lock_group(sb, i);
2946                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2947                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2948                                  "Checksum for group %u failed (%u!=%u)",
2949                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2950                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2951                         if (!sb_rdonly(sb)) {
2952                                 ext4_unlock_group(sb, i);
2953                                 return 0;
2954                         }
2955                 }
2956                 ext4_unlock_group(sb, i);
2957                 if (!flexbg_flag)
2958                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2959         }
2960         if (NULL != first_not_zeroed)
2961                 *first_not_zeroed = grp;
2962         return 1;
2963 }
2964
2965 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2966  * the superblock) which were deleted from all directories, but held open by
2967  * a process at the time of a crash.  We walk the list and try to delete these
2968  * inodes at recovery time (only with a read-write filesystem).
2969  *
2970  * In order to keep the orphan inode chain consistent during traversal (in
2971  * case of crash during recovery), we link each inode into the superblock
2972  * orphan list_head and handle it the same way as an inode deletion during
2973  * normal operation (which journals the operations for us).
2974  *
2975  * We only do an iget() and an iput() on each inode, which is very safe if we
2976  * accidentally point at an in-use or already deleted inode.  The worst that
2977  * can happen in this case is that we get a "bit already cleared" message from
2978  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2979  * e2fsck was run on this filesystem, and it must have already done the orphan
2980  * inode cleanup for us, so we can safely abort without any further action.
2981  */
2982 static void ext4_orphan_cleanup(struct super_block *sb,
2983                                 struct ext4_super_block *es)
2984 {
2985         unsigned int s_flags = sb->s_flags;
2986         int ret, nr_orphans = 0, nr_truncates = 0;
2987 #ifdef CONFIG_QUOTA
2988         int quota_update = 0;
2989         int i;
2990 #endif
2991         if (!es->s_last_orphan) {
2992                 jbd_debug(4, "no orphan inodes to clean up\n");
2993                 return;
2994         }
2995
2996         if (bdev_read_only(sb->s_bdev)) {
2997                 ext4_msg(sb, KERN_ERR, "write access "
2998                         "unavailable, skipping orphan cleanup");
2999                 return;
3000         }
3001
3002         /* Check if feature set would not allow a r/w mount */
3003         if (!ext4_feature_set_ok(sb, 0)) {
3004                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
3005                          "unknown ROCOMPAT features");
3006                 return;
3007         }
3008
3009         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
3010                 /* don't clear list on RO mount w/ errors */
3011                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
3012                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
3013                                   "clearing orphan list.\n");
3014                         es->s_last_orphan = 0;
3015                 }
3016                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
3017                 return;
3018         }
3019
3020         if (s_flags & SB_RDONLY) {
3021                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
3022                 sb->s_flags &= ~SB_RDONLY;
3023         }
3024 #ifdef CONFIG_QUOTA
3025         /* Needed for iput() to work correctly and not trash data */
3026         sb->s_flags |= SB_ACTIVE;
3027
3028         /*
3029          * Turn on quotas which were not enabled for read-only mounts if
3030          * filesystem has quota feature, so that they are updated correctly.
3031          */
3032         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
3033                 int ret = ext4_enable_quotas(sb);
3034
3035                 if (!ret)
3036                         quota_update = 1;
3037                 else
3038                         ext4_msg(sb, KERN_ERR,
3039                                 "Cannot turn on quotas: error %d", ret);
3040         }
3041
3042         /* Turn on journaled quotas used for old sytle */
3043         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3044                 if (EXT4_SB(sb)->s_qf_names[i]) {
3045                         int ret = ext4_quota_on_mount(sb, i);
3046
3047                         if (!ret)
3048                                 quota_update = 1;
3049                         else
3050                                 ext4_msg(sb, KERN_ERR,
3051                                         "Cannot turn on journaled "
3052                                         "quota: type %d: error %d", i, ret);
3053                 }
3054         }
3055 #endif
3056
3057         while (es->s_last_orphan) {
3058                 struct inode *inode;
3059
3060                 /*
3061                  * We may have encountered an error during cleanup; if
3062                  * so, skip the rest.
3063                  */
3064                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
3065                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
3066                         es->s_last_orphan = 0;
3067                         break;
3068                 }
3069
3070                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
3071                 if (IS_ERR(inode)) {
3072                         es->s_last_orphan = 0;
3073                         break;
3074                 }
3075
3076                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
3077                 dquot_initialize(inode);
3078                 if (inode->i_nlink) {
3079                         if (test_opt(sb, DEBUG))
3080                                 ext4_msg(sb, KERN_DEBUG,
3081                                         "%s: truncating inode %lu to %lld bytes",
3082                                         __func__, inode->i_ino, inode->i_size);
3083                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
3084                                   inode->i_ino, inode->i_size);
3085                         inode_lock(inode);
3086                         truncate_inode_pages(inode->i_mapping, inode->i_size);
3087                         ret = ext4_truncate(inode);
3088                         if (ret)
3089                                 ext4_std_error(inode->i_sb, ret);
3090                         inode_unlock(inode);
3091                         nr_truncates++;
3092                 } else {
3093                         if (test_opt(sb, DEBUG))
3094                                 ext4_msg(sb, KERN_DEBUG,
3095                                         "%s: deleting unreferenced inode %lu",
3096                                         __func__, inode->i_ino);
3097                         jbd_debug(2, "deleting unreferenced inode %lu\n",
3098                                   inode->i_ino);
3099                         nr_orphans++;
3100                 }
3101                 iput(inode);  /* The delete magic happens here! */
3102         }
3103
3104 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
3105
3106         if (nr_orphans)
3107                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
3108                        PLURAL(nr_orphans));
3109         if (nr_truncates)
3110                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
3111                        PLURAL(nr_truncates));
3112 #ifdef CONFIG_QUOTA
3113         /* Turn off quotas if they were enabled for orphan cleanup */
3114         if (quota_update) {
3115                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3116                         if (sb_dqopt(sb)->files[i])
3117                                 dquot_quota_off(sb, i);
3118                 }
3119         }
3120 #endif
3121         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
3122 }
3123
3124 /*
3125  * Maximal extent format file size.
3126  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3127  * extent format containers, within a sector_t, and within i_blocks
3128  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3129  * so that won't be a limiting factor.
3130  *
3131  * However there is other limiting factor. We do store extents in the form
3132  * of starting block and length, hence the resulting length of the extent
3133  * covering maximum file size must fit into on-disk format containers as
3134  * well. Given that length is always by 1 unit bigger than max unit (because
3135  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3136  *
3137  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3138  */
3139 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3140 {
3141         loff_t res;
3142         loff_t upper_limit = MAX_LFS_FILESIZE;
3143
3144         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3145
3146         if (!has_huge_files) {
3147                 upper_limit = (1LL << 32) - 1;
3148
3149                 /* total blocks in file system block size */
3150                 upper_limit >>= (blkbits - 9);
3151                 upper_limit <<= blkbits;
3152         }
3153
3154         /*
3155          * 32-bit extent-start container, ee_block. We lower the maxbytes
3156          * by one fs block, so ee_len can cover the extent of maximum file
3157          * size
3158          */
3159         res = (1LL << 32) - 1;
3160         res <<= blkbits;
3161
3162         /* Sanity check against vm- & vfs- imposed limits */
3163         if (res > upper_limit)
3164                 res = upper_limit;
3165
3166         return res;
3167 }
3168
3169 /*
3170  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3171  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3172  * We need to be 1 filesystem block less than the 2^48 sector limit.
3173  */
3174 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3175 {
3176         loff_t res = EXT4_NDIR_BLOCKS;
3177         int meta_blocks;
3178         loff_t upper_limit;
3179         /* This is calculated to be the largest file size for a dense, block
3180          * mapped file such that the file's total number of 512-byte sectors,
3181          * including data and all indirect blocks, does not exceed (2^48 - 1).
3182          *
3183          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3184          * number of 512-byte sectors of the file.
3185          */
3186
3187         if (!has_huge_files) {
3188                 /*
3189                  * !has_huge_files or implies that the inode i_block field
3190                  * represents total file blocks in 2^32 512-byte sectors ==
3191                  * size of vfs inode i_blocks * 8
3192                  */
3193                 upper_limit = (1LL << 32) - 1;
3194
3195                 /* total blocks in file system block size */
3196                 upper_limit >>= (bits - 9);
3197
3198         } else {
3199                 /*
3200                  * We use 48 bit ext4_inode i_blocks
3201                  * With EXT4_HUGE_FILE_FL set the i_blocks
3202                  * represent total number of blocks in
3203                  * file system block size
3204                  */
3205                 upper_limit = (1LL << 48) - 1;
3206
3207         }
3208
3209         /* indirect blocks */
3210         meta_blocks = 1;
3211         /* double indirect blocks */
3212         meta_blocks += 1 + (1LL << (bits-2));
3213         /* tripple indirect blocks */
3214         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
3215
3216         upper_limit -= meta_blocks;
3217         upper_limit <<= bits;
3218
3219         res += 1LL << (bits-2);
3220         res += 1LL << (2*(bits-2));
3221         res += 1LL << (3*(bits-2));
3222         res <<= bits;
3223         if (res > upper_limit)
3224                 res = upper_limit;
3225
3226         if (res > MAX_LFS_FILESIZE)
3227                 res = MAX_LFS_FILESIZE;
3228
3229         return res;
3230 }
3231
3232 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3233                                    ext4_fsblk_t logical_sb_block, int nr)
3234 {
3235         struct ext4_sb_info *sbi = EXT4_SB(sb);
3236         ext4_group_t bg, first_meta_bg;
3237         int has_super = 0;
3238
3239         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3240
3241         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3242                 return logical_sb_block + nr + 1;
3243         bg = sbi->s_desc_per_block * nr;
3244         if (ext4_bg_has_super(sb, bg))
3245                 has_super = 1;
3246
3247         /*
3248          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3249          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3250          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3251          * compensate.
3252          */
3253         if (sb->s_blocksize == 1024 && nr == 0 &&
3254             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3255                 has_super++;
3256
3257         return (has_super + ext4_group_first_block_no(sb, bg));
3258 }
3259
3260 /**
3261  * ext4_get_stripe_size: Get the stripe size.
3262  * @sbi: In memory super block info
3263  *
3264  * If we have specified it via mount option, then
3265  * use the mount option value. If the value specified at mount time is
3266  * greater than the blocks per group use the super block value.
3267  * If the super block value is greater than blocks per group return 0.
3268  * Allocator needs it be less than blocks per group.
3269  *
3270  */
3271 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3272 {
3273         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3274         unsigned long stripe_width =
3275                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3276         int ret;
3277
3278         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3279                 ret = sbi->s_stripe;
3280         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3281                 ret = stripe_width;
3282         else if (stride && stride <= sbi->s_blocks_per_group)
3283                 ret = stride;
3284         else
3285                 ret = 0;
3286
3287         /*
3288          * If the stripe width is 1, this makes no sense and
3289          * we set it to 0 to turn off stripe handling code.
3290          */
3291         if (ret <= 1)
3292                 ret = 0;
3293
3294         return ret;
3295 }
3296
3297 /*
3298  * Check whether this filesystem can be mounted based on
3299  * the features present and the RDONLY/RDWR mount requested.
3300  * Returns 1 if this filesystem can be mounted as requested,
3301  * 0 if it cannot be.
3302  */
3303 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
3304 {
3305         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3306                 ext4_msg(sb, KERN_ERR,
3307                         "Couldn't mount because of "
3308                         "unsupported optional features (%x)",
3309                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3310                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3311                 return 0;
3312         }
3313
3314 #ifndef CONFIG_UNICODE
3315         if (ext4_has_feature_casefold(sb)) {
3316                 ext4_msg(sb, KERN_ERR,
3317                          "Filesystem with casefold feature cannot be "
3318                          "mounted without CONFIG_UNICODE");
3319                 return 0;
3320         }
3321 #endif
3322
3323         if (readonly)
3324                 return 1;
3325
3326         if (ext4_has_feature_readonly(sb)) {
3327                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3328                 sb->s_flags |= SB_RDONLY;
3329                 return 1;
3330         }
3331
3332         /* Check that feature set is OK for a read-write mount */
3333         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3334                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3335                          "unsupported optional features (%x)",
3336                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3337                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3338                 return 0;
3339         }
3340         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3341                 ext4_msg(sb, KERN_ERR,
3342                          "Can't support bigalloc feature without "
3343                          "extents feature\n");
3344                 return 0;
3345         }
3346
3347 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3348         if (!readonly && (ext4_has_feature_quota(sb) ||
3349                           ext4_has_feature_project(sb))) {
3350                 ext4_msg(sb, KERN_ERR,
3351                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3352                 return 0;
3353         }
3354 #endif  /* CONFIG_QUOTA */
3355         return 1;
3356 }
3357
3358 /*
3359  * This function is called once a day if we have errors logged
3360  * on the file system
3361  */
3362 static void print_daily_error_info(struct timer_list *t)
3363 {
3364         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3365         struct super_block *sb = sbi->s_sb;
3366         struct ext4_super_block *es = sbi->s_es;
3367
3368         if (es->s_error_count)
3369                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3370                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3371                          le32_to_cpu(es->s_error_count));
3372         if (es->s_first_error_time) {
3373                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3374                        sb->s_id,
3375                        ext4_get_tstamp(es, s_first_error_time),
3376                        (int) sizeof(es->s_first_error_func),
3377                        es->s_first_error_func,
3378                        le32_to_cpu(es->s_first_error_line));
3379                 if (es->s_first_error_ino)
3380                         printk(KERN_CONT ": inode %u",
3381                                le32_to_cpu(es->s_first_error_ino));
3382                 if (es->s_first_error_block)
3383                         printk(KERN_CONT ": block %llu", (unsigned long long)
3384                                le64_to_cpu(es->s_first_error_block));
3385                 printk(KERN_CONT "\n");
3386         }
3387         if (es->s_last_error_time) {
3388                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3389                        sb->s_id,
3390                        ext4_get_tstamp(es, s_last_error_time),
3391                        (int) sizeof(es->s_last_error_func),
3392                        es->s_last_error_func,
3393                        le32_to_cpu(es->s_last_error_line));
3394                 if (es->s_last_error_ino)
3395                         printk(KERN_CONT ": inode %u",
3396                                le32_to_cpu(es->s_last_error_ino));
3397                 if (es->s_last_error_block)
3398                         printk(KERN_CONT ": block %llu", (unsigned long long)
3399                                le64_to_cpu(es->s_last_error_block));
3400                 printk(KERN_CONT "\n");
3401         }
3402         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3403 }
3404
3405 /* Find next suitable group and run ext4_init_inode_table */
3406 static int ext4_run_li_request(struct ext4_li_request *elr)
3407 {
3408         struct ext4_group_desc *gdp = NULL;
3409         struct super_block *sb = elr->lr_super;
3410         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3411         ext4_group_t group = elr->lr_next_group;
3412         unsigned long timeout = 0;
3413         unsigned int prefetch_ios = 0;
3414         int ret = 0;
3415
3416         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3417                 elr->lr_next_group = ext4_mb_prefetch(sb, group,
3418                                 EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3419                 if (prefetch_ios)
3420                         ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3421                                               prefetch_ios);
3422                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3423                                             prefetch_ios);
3424                 if (group >= elr->lr_next_group) {
3425                         ret = 1;
3426                         if (elr->lr_first_not_zeroed != ngroups &&
3427                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3428                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3429                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3430                                 ret = 0;
3431                         }
3432                 }
3433                 return ret;
3434         }
3435
3436         for (; group < ngroups; group++) {
3437                 gdp = ext4_get_group_desc(sb, group, NULL);
3438                 if (!gdp) {
3439                         ret = 1;
3440                         break;
3441                 }
3442
3443                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3444                         break;
3445         }
3446
3447         if (group >= ngroups)
3448                 ret = 1;
3449
3450         if (!ret) {
3451                 timeout = jiffies;
3452                 ret = ext4_init_inode_table(sb, group,
3453                                             elr->lr_timeout ? 0 : 1);
3454                 trace_ext4_lazy_itable_init(sb, group);
3455                 if (elr->lr_timeout == 0) {
3456                         timeout = (jiffies - timeout) *
3457                                 EXT4_SB(elr->lr_super)->s_li_wait_mult;
3458                         elr->lr_timeout = timeout;
3459                 }
3460                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3461                 elr->lr_next_group = group + 1;
3462         }
3463         return ret;
3464 }
3465
3466 /*
3467  * Remove lr_request from the list_request and free the
3468  * request structure. Should be called with li_list_mtx held
3469  */
3470 static void ext4_remove_li_request(struct ext4_li_request *elr)
3471 {
3472         if (!elr)
3473                 return;
3474
3475         list_del(&elr->lr_request);
3476         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3477         kfree(elr);
3478 }
3479
3480 static void ext4_unregister_li_request(struct super_block *sb)
3481 {
3482         mutex_lock(&ext4_li_mtx);
3483         if (!ext4_li_info) {
3484                 mutex_unlock(&ext4_li_mtx);
3485                 return;
3486         }
3487
3488         mutex_lock(&ext4_li_info->li_list_mtx);
3489         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3490         mutex_unlock(&ext4_li_info->li_list_mtx);
3491         mutex_unlock(&ext4_li_mtx);
3492 }
3493
3494 static struct task_struct *ext4_lazyinit_task;
3495
3496 /*
3497  * This is the function where ext4lazyinit thread lives. It walks
3498  * through the request list searching for next scheduled filesystem.
3499  * When such a fs is found, run the lazy initialization request
3500  * (ext4_rn_li_request) and keep track of the time spend in this
3501  * function. Based on that time we compute next schedule time of
3502  * the request. When walking through the list is complete, compute
3503  * next waking time and put itself into sleep.
3504  */
3505 static int ext4_lazyinit_thread(void *arg)
3506 {
3507         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3508         struct list_head *pos, *n;
3509         struct ext4_li_request *elr;
3510         unsigned long next_wakeup, cur;
3511
3512         BUG_ON(NULL == eli);
3513
3514 cont_thread:
3515         while (true) {
3516                 next_wakeup = MAX_JIFFY_OFFSET;
3517
3518                 mutex_lock(&eli->li_list_mtx);
3519                 if (list_empty(&eli->li_request_list)) {
3520                         mutex_unlock(&eli->li_list_mtx);
3521                         goto exit_thread;
3522                 }
3523                 list_for_each_safe(pos, n, &eli->li_request_list) {
3524                         int err = 0;
3525                         int progress = 0;
3526                         elr = list_entry(pos, struct ext4_li_request,
3527                                          lr_request);
3528
3529                         if (time_before(jiffies, elr->lr_next_sched)) {
3530                                 if (time_before(elr->lr_next_sched, next_wakeup))
3531                                         next_wakeup = elr->lr_next_sched;
3532                                 continue;
3533                         }
3534                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3535                                 if (sb_start_write_trylock(elr->lr_super)) {
3536                                         progress = 1;
3537                                         /*
3538                                          * We hold sb->s_umount, sb can not
3539                                          * be removed from the list, it is
3540                                          * now safe to drop li_list_mtx
3541                                          */
3542                                         mutex_unlock(&eli->li_list_mtx);
3543                                         err = ext4_run_li_request(elr);
3544                                         sb_end_write(elr->lr_super);
3545                                         mutex_lock(&eli->li_list_mtx);
3546                                         n = pos->next;
3547                                 }
3548                                 up_read((&elr->lr_super->s_umount));
3549                         }
3550                         /* error, remove the lazy_init job */
3551                         if (err) {
3552                                 ext4_remove_li_request(elr);
3553                                 continue;
3554                         }
3555                         if (!progress) {
3556                                 elr->lr_next_sched = jiffies +
3557                                         (prandom_u32()
3558                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3559                         }
3560                         if (time_before(elr->lr_next_sched, next_wakeup))
3561                                 next_wakeup = elr->lr_next_sched;
3562                 }
3563                 mutex_unlock(&eli->li_list_mtx);
3564
3565                 try_to_freeze();
3566
3567                 cur = jiffies;
3568                 if ((time_after_eq(cur, next_wakeup)) ||
3569                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3570                         cond_resched();
3571                         continue;
3572                 }
3573
3574                 schedule_timeout_interruptible(next_wakeup - cur);
3575
3576                 if (kthread_should_stop()) {
3577                         ext4_clear_request_list();
3578                         goto exit_thread;
3579                 }
3580         }
3581
3582 exit_thread:
3583         /*
3584          * It looks like the request list is empty, but we need
3585          * to check it under the li_list_mtx lock, to prevent any
3586          * additions into it, and of course we should lock ext4_li_mtx
3587          * to atomically free the list and ext4_li_info, because at
3588          * this point another ext4 filesystem could be registering
3589          * new one.
3590          */
3591         mutex_lock(&ext4_li_mtx);
3592         mutex_lock(&eli->li_list_mtx);
3593         if (!list_empty(&eli->li_request_list)) {
3594                 mutex_unlock(&eli->li_list_mtx);
3595                 mutex_unlock(&ext4_li_mtx);
3596                 goto cont_thread;
3597         }
3598         mutex_unlock(&eli->li_list_mtx);
3599         kfree(ext4_li_info);
3600         ext4_li_info = NULL;
3601         mutex_unlock(&ext4_li_mtx);
3602
3603         return 0;
3604 }
3605
3606 static void ext4_clear_request_list(void)
3607 {
3608         struct list_head *pos, *n;
3609         struct ext4_li_request *elr;
3610
3611         mutex_lock(&ext4_li_info->li_list_mtx);
3612         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3613                 elr = list_entry(pos, struct ext4_li_request,
3614                                  lr_request);
3615                 ext4_remove_li_request(elr);
3616         }
3617         mutex_unlock(&ext4_li_info->li_list_mtx);
3618 }
3619
3620 static int ext4_run_lazyinit_thread(void)
3621 {
3622         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3623                                          ext4_li_info, "ext4lazyinit");
3624         if (IS_ERR(ext4_lazyinit_task)) {
3625                 int err = PTR_ERR(ext4_lazyinit_task);
3626                 ext4_clear_request_list();
3627                 kfree(ext4_li_info);
3628                 ext4_li_info = NULL;
3629                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3630                                  "initialization thread\n",
3631                                  err);
3632                 return err;
3633         }
3634         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3635         return 0;
3636 }
3637
3638 /*
3639  * Check whether it make sense to run itable init. thread or not.
3640  * If there is at least one uninitialized inode table, return
3641  * corresponding group number, else the loop goes through all
3642  * groups and return total number of groups.
3643  */
3644 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3645 {
3646         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3647         struct ext4_group_desc *gdp = NULL;
3648
3649         if (!ext4_has_group_desc_csum(sb))
3650                 return ngroups;
3651
3652         for (group = 0; group < ngroups; group++) {
3653                 gdp = ext4_get_group_desc(sb, group, NULL);
3654                 if (!gdp)
3655                         continue;
3656
3657                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3658                         break;
3659         }
3660
3661         return group;
3662 }
3663
3664 static int ext4_li_info_new(void)
3665 {
3666         struct ext4_lazy_init *eli = NULL;
3667
3668         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3669         if (!eli)
3670                 return -ENOMEM;
3671
3672         INIT_LIST_HEAD(&eli->li_request_list);
3673         mutex_init(&eli->li_list_mtx);
3674
3675         eli->li_state |= EXT4_LAZYINIT_QUIT;
3676
3677         ext4_li_info = eli;
3678
3679         return 0;
3680 }
3681
3682 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3683                                             ext4_group_t start)
3684 {
3685         struct ext4_li_request *elr;
3686
3687         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3688         if (!elr)
3689                 return NULL;
3690
3691         elr->lr_super = sb;
3692         elr->lr_first_not_zeroed = start;
3693         if (test_opt(sb, PREFETCH_BLOCK_BITMAPS))
3694                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3695         else {
3696                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3697                 elr->lr_next_group = start;
3698         }
3699
3700         /*
3701          * Randomize first schedule time of the request to
3702          * spread the inode table initialization requests
3703          * better.
3704          */
3705         elr->lr_next_sched = jiffies + (prandom_u32() %
3706                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3707         return elr;
3708 }
3709
3710 int ext4_register_li_request(struct super_block *sb,
3711                              ext4_group_t first_not_zeroed)
3712 {
3713         struct ext4_sb_info *sbi = EXT4_SB(sb);
3714         struct ext4_li_request *elr = NULL;
3715         ext4_group_t ngroups = sbi->s_groups_count;
3716         int ret = 0;
3717
3718         mutex_lock(&ext4_li_mtx);
3719         if (sbi->s_li_request != NULL) {
3720                 /*
3721                  * Reset timeout so it can be computed again, because
3722                  * s_li_wait_mult might have changed.
3723                  */
3724                 sbi->s_li_request->lr_timeout = 0;
3725                 goto out;
3726         }
3727
3728         if (!test_opt(sb, PREFETCH_BLOCK_BITMAPS) &&
3729             (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3730              !test_opt(sb, INIT_INODE_TABLE)))
3731                 goto out;
3732
3733         elr = ext4_li_request_new(sb, first_not_zeroed);
3734         if (!elr) {
3735                 ret = -ENOMEM;
3736                 goto out;
3737         }
3738
3739         if (NULL == ext4_li_info) {
3740                 ret = ext4_li_info_new();
3741                 if (ret)
3742                         goto out;
3743         }
3744
3745         mutex_lock(&ext4_li_info->li_list_mtx);
3746         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3747         mutex_unlock(&ext4_li_info->li_list_mtx);
3748
3749         sbi->s_li_request = elr;
3750         /*
3751          * set elr to NULL here since it has been inserted to
3752          * the request_list and the removal and free of it is
3753          * handled by ext4_clear_request_list from now on.
3754          */
3755         elr = NULL;
3756
3757         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3758                 ret = ext4_run_lazyinit_thread();
3759                 if (ret)
3760                         goto out;
3761         }
3762 out:
3763         mutex_unlock(&ext4_li_mtx);
3764         if (ret)
3765                 kfree(elr);
3766         return ret;
3767 }
3768
3769 /*
3770  * We do not need to lock anything since this is called on
3771  * module unload.
3772  */
3773 static void ext4_destroy_lazyinit_thread(void)
3774 {
3775         /*
3776          * If thread exited earlier
3777          * there's nothing to be done.
3778          */
3779         if (!ext4_li_info || !ext4_lazyinit_task)
3780                 return;
3781
3782         kthread_stop(ext4_lazyinit_task);
3783 }
3784
3785 static int set_journal_csum_feature_set(struct super_block *sb)
3786 {
3787         int ret = 1;
3788         int compat, incompat;
3789         struct ext4_sb_info *sbi = EXT4_SB(sb);
3790
3791         if (ext4_has_metadata_csum(sb)) {
3792                 /* journal checksum v3 */
3793                 compat = 0;
3794                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3795         } else {
3796                 /* journal checksum v1 */
3797                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3798                 incompat = 0;
3799         }
3800
3801         jbd2_journal_clear_features(sbi->s_journal,
3802                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3803                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3804                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3805         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3806                 ret = jbd2_journal_set_features(sbi->s_journal,
3807                                 compat, 0,
3808                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3809                                 incompat);
3810         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3811                 ret = jbd2_journal_set_features(sbi->s_journal,
3812                                 compat, 0,
3813                                 incompat);
3814                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3815                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3816         } else {
3817                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3818                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3819         }
3820
3821         return ret;
3822 }
3823
3824 /*
3825  * Note: calculating the overhead so we can be compatible with
3826  * historical BSD practice is quite difficult in the face of
3827  * clusters/bigalloc.  This is because multiple metadata blocks from
3828  * different block group can end up in the same allocation cluster.
3829  * Calculating the exact overhead in the face of clustered allocation
3830  * requires either O(all block bitmaps) in memory or O(number of block
3831  * groups**2) in time.  We will still calculate the superblock for
3832  * older file systems --- and if we come across with a bigalloc file
3833  * system with zero in s_overhead_clusters the estimate will be close to
3834  * correct especially for very large cluster sizes --- but for newer
3835  * file systems, it's better to calculate this figure once at mkfs
3836  * time, and store it in the superblock.  If the superblock value is
3837  * present (even for non-bigalloc file systems), we will use it.
3838  */
3839 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3840                           char *buf)
3841 {
3842         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3843         struct ext4_group_desc  *gdp;
3844         ext4_fsblk_t            first_block, last_block, b;
3845         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3846         int                     s, j, count = 0;
3847
3848         if (!ext4_has_feature_bigalloc(sb))
3849                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3850                         sbi->s_itb_per_group + 2);
3851
3852         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3853                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3854         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3855         for (i = 0; i < ngroups; i++) {
3856                 gdp = ext4_get_group_desc(sb, i, NULL);
3857                 b = ext4_block_bitmap(sb, gdp);
3858                 if (b >= first_block && b <= last_block) {
3859                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3860                         count++;
3861                 }
3862                 b = ext4_inode_bitmap(sb, gdp);
3863                 if (b >= first_block && b <= last_block) {
3864                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3865                         count++;
3866                 }
3867                 b = ext4_inode_table(sb, gdp);
3868                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3869                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3870                                 int c = EXT4_B2C(sbi, b - first_block);
3871                                 ext4_set_bit(c, buf);
3872                                 count++;
3873                         }
3874                 if (i != grp)
3875                         continue;
3876                 s = 0;
3877                 if (ext4_bg_has_super(sb, grp)) {
3878                         ext4_set_bit(s++, buf);
3879                         count++;
3880                 }
3881                 j = ext4_bg_num_gdb(sb, grp);
3882                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3883                         ext4_error(sb, "Invalid number of block group "
3884                                    "descriptor blocks: %d", j);
3885                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3886                 }
3887                 count += j;
3888                 for (; j > 0; j--)
3889                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3890         }
3891         if (!count)
3892                 return 0;
3893         return EXT4_CLUSTERS_PER_GROUP(sb) -
3894                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3895 }
3896
3897 /*
3898  * Compute the overhead and stash it in sbi->s_overhead
3899  */
3900 int ext4_calculate_overhead(struct super_block *sb)
3901 {
3902         struct ext4_sb_info *sbi = EXT4_SB(sb);
3903         struct ext4_super_block *es = sbi->s_es;
3904         struct inode *j_inode;
3905         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3906         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3907         ext4_fsblk_t overhead = 0;
3908         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3909
3910         if (!buf)
3911                 return -ENOMEM;
3912
3913         /*
3914          * Compute the overhead (FS structures).  This is constant
3915          * for a given filesystem unless the number of block groups
3916          * changes so we cache the previous value until it does.
3917          */
3918
3919         /*
3920          * All of the blocks before first_data_block are overhead
3921          */
3922         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3923
3924         /*
3925          * Add the overhead found in each block group
3926          */
3927         for (i = 0; i < ngroups; i++) {
3928                 int blks;
3929
3930                 blks = count_overhead(sb, i, buf);
3931                 overhead += blks;
3932                 if (blks)
3933                         memset(buf, 0, PAGE_SIZE);
3934                 cond_resched();
3935         }
3936
3937         /*
3938          * Add the internal journal blocks whether the journal has been
3939          * loaded or not
3940          */
3941         if (sbi->s_journal && !sbi->s_journal_bdev)
3942                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
3943         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3944                 /* j_inum for internal journal is non-zero */
3945                 j_inode = ext4_get_journal_inode(sb, j_inum);
3946                 if (j_inode) {
3947                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3948                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3949                         iput(j_inode);
3950                 } else {
3951                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3952                 }
3953         }
3954         sbi->s_overhead = overhead;
3955         smp_wmb();
3956         free_page((unsigned long) buf);
3957         return 0;
3958 }
3959
3960 static void ext4_set_resv_clusters(struct super_block *sb)
3961 {
3962         ext4_fsblk_t resv_clusters;
3963         struct ext4_sb_info *sbi = EXT4_SB(sb);
3964
3965         /*
3966          * There's no need to reserve anything when we aren't using extents.
3967          * The space estimates are exact, there are no unwritten extents,
3968          * hole punching doesn't need new metadata... This is needed especially
3969          * to keep ext2/3 backward compatibility.
3970          */
3971         if (!ext4_has_feature_extents(sb))
3972                 return;
3973         /*
3974          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3975          * This should cover the situations where we can not afford to run
3976          * out of space like for example punch hole, or converting
3977          * unwritten extents in delalloc path. In most cases such
3978          * allocation would require 1, or 2 blocks, higher numbers are
3979          * very rare.
3980          */
3981         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3982                          sbi->s_cluster_bits);
3983
3984         do_div(resv_clusters, 50);
3985         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3986
3987         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3988 }
3989
3990 static const char *ext4_quota_mode(struct super_block *sb)
3991 {
3992 #ifdef CONFIG_QUOTA
3993         if (!ext4_quota_capable(sb))
3994                 return "none";
3995
3996         if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
3997                 return "journalled";
3998         else
3999                 return "writeback";
4000 #else
4001         return "disabled";
4002 #endif
4003 }
4004
4005 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
4006 {
4007         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
4008         char *orig_data = kstrdup(data, GFP_KERNEL);
4009         struct buffer_head *bh, **group_desc;
4010         struct ext4_super_block *es = NULL;
4011         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4012         struct flex_groups **flex_groups;
4013         ext4_fsblk_t block;
4014         ext4_fsblk_t sb_block = get_sb_block(&data);
4015         ext4_fsblk_t logical_sb_block;
4016         unsigned long offset = 0;
4017         unsigned long journal_devnum = 0;
4018         unsigned long def_mount_opts;
4019         struct inode *root;
4020         const char *descr;
4021         int ret = -ENOMEM;
4022         int blocksize, clustersize;
4023         unsigned int db_count;
4024         unsigned int i;
4025         int needs_recovery, has_huge_files;
4026         __u64 blocks_count;
4027         int err = 0;
4028         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4029         ext4_group_t first_not_zeroed;
4030
4031         if ((data && !orig_data) || !sbi)
4032                 goto out_free_base;
4033
4034         sbi->s_daxdev = dax_dev;
4035         sbi->s_blockgroup_lock =
4036                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4037         if (!sbi->s_blockgroup_lock)
4038                 goto out_free_base;
4039
4040         sb->s_fs_info = sbi;
4041         sbi->s_sb = sb;
4042         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
4043         sbi->s_sb_block = sb_block;
4044         sbi->s_sectors_written_start =
4045                 part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
4046
4047         /* Cleanup superblock name */
4048         strreplace(sb->s_id, '/', '!');
4049
4050         /* -EINVAL is default */
4051         ret = -EINVAL;
4052         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
4053         if (!blocksize) {
4054                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
4055                 goto out_fail;
4056         }
4057
4058         /*
4059          * The ext4 superblock will not be buffer aligned for other than 1kB
4060          * block sizes.  We need to calculate the offset from buffer start.
4061          */
4062         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
4063                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4064                 offset = do_div(logical_sb_block, blocksize);
4065         } else {
4066                 logical_sb_block = sb_block;
4067         }
4068
4069         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4070         if (IS_ERR(bh)) {
4071                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
4072                 ret = PTR_ERR(bh);
4073                 goto out_fail;
4074         }
4075         /*
4076          * Note: s_es must be initialized as soon as possible because
4077          *       some ext4 macro-instructions depend on its value
4078          */
4079         es = (struct ext4_super_block *) (bh->b_data + offset);
4080         sbi->s_es = es;
4081         sb->s_magic = le16_to_cpu(es->s_magic);
4082         if (sb->s_magic != EXT4_SUPER_MAGIC)
4083                 goto cantfind_ext4;
4084         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
4085
4086         /* Warn if metadata_csum and gdt_csum are both set. */
4087         if (ext4_has_feature_metadata_csum(sb) &&
4088             ext4_has_feature_gdt_csum(sb))
4089                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4090                              "redundant flags; please run fsck.");
4091
4092         /* Check for a known checksum algorithm */
4093         if (!ext4_verify_csum_type(sb, es)) {
4094                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4095                          "unknown checksum algorithm.");
4096                 silent = 1;
4097                 goto cantfind_ext4;
4098         }
4099
4100         /* Load the checksum driver */
4101         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4102         if (IS_ERR(sbi->s_chksum_driver)) {
4103                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4104                 ret = PTR_ERR(sbi->s_chksum_driver);
4105                 sbi->s_chksum_driver = NULL;
4106                 goto failed_mount;
4107         }
4108
4109         /* Check superblock checksum */
4110         if (!ext4_superblock_csum_verify(sb, es)) {
4111                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4112                          "invalid superblock checksum.  Run e2fsck?");
4113                 silent = 1;
4114                 ret = -EFSBADCRC;
4115                 goto cantfind_ext4;
4116         }
4117
4118         /* Precompute checksum seed for all metadata */
4119         if (ext4_has_feature_csum_seed(sb))
4120                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4121         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4122                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4123                                                sizeof(es->s_uuid));
4124
4125         /* Set defaults before we parse the mount options */
4126         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4127         set_opt(sb, INIT_INODE_TABLE);
4128         if (def_mount_opts & EXT4_DEFM_DEBUG)
4129                 set_opt(sb, DEBUG);
4130         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4131                 set_opt(sb, GRPID);
4132         if (def_mount_opts & EXT4_DEFM_UID16)
4133                 set_opt(sb, NO_UID32);
4134         /* xattr user namespace & acls are now defaulted on */
4135         set_opt(sb, XATTR_USER);
4136 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4137         set_opt(sb, POSIX_ACL);
4138 #endif
4139         if (ext4_has_feature_fast_commit(sb))
4140                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4141         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4142         if (ext4_has_metadata_csum(sb))
4143                 set_opt(sb, JOURNAL_CHECKSUM);
4144
4145         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4146                 set_opt(sb, JOURNAL_DATA);
4147         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4148                 set_opt(sb, ORDERED_DATA);
4149         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4150                 set_opt(sb, WRITEBACK_DATA);
4151
4152         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
4153                 set_opt(sb, ERRORS_PANIC);
4154         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
4155                 set_opt(sb, ERRORS_CONT);
4156         else
4157                 set_opt(sb, ERRORS_RO);
4158         /* block_validity enabled by default; disable with noblock_validity */
4159         set_opt(sb, BLOCK_VALIDITY);
4160         if (def_mount_opts & EXT4_DEFM_DISCARD)
4161                 set_opt(sb, DISCARD);
4162
4163         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
4164         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
4165         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
4166         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
4167         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
4168
4169         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4170                 set_opt(sb, BARRIER);
4171
4172         /*
4173          * enable delayed allocation by default
4174          * Use -o nodelalloc to turn it off
4175          */
4176         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4177             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4178                 set_opt(sb, DELALLOC);
4179
4180         /*
4181          * set default s_li_wait_mult for lazyinit, for the case there is
4182          * no mount option specified.
4183          */
4184         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
4185
4186         if (le32_to_cpu(es->s_log_block_size) >
4187             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4188                 ext4_msg(sb, KERN_ERR,
4189                          "Invalid log block size: %u",
4190                          le32_to_cpu(es->s_log_block_size));
4191                 goto failed_mount;
4192         }
4193         if (le32_to_cpu(es->s_log_cluster_size) >
4194             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4195                 ext4_msg(sb, KERN_ERR,
4196                          "Invalid log cluster size: %u",
4197                          le32_to_cpu(es->s_log_cluster_size));
4198                 goto failed_mount;
4199         }
4200
4201         blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
4202
4203         if (blocksize == PAGE_SIZE)
4204                 set_opt(sb, DIOREAD_NOLOCK);
4205
4206         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4207                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4208                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4209         } else {
4210                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4211                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4212                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4213                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4214                                  sbi->s_first_ino);
4215                         goto failed_mount;
4216                 }
4217                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4218                     (!is_power_of_2(sbi->s_inode_size)) ||
4219                     (sbi->s_inode_size > blocksize)) {
4220                         ext4_msg(sb, KERN_ERR,
4221                                "unsupported inode size: %d",
4222                                sbi->s_inode_size);
4223                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
4224                         goto failed_mount;
4225                 }
4226                 /*
4227                  * i_atime_extra is the last extra field available for
4228                  * [acm]times in struct ext4_inode. Checking for that
4229                  * field should suffice to ensure we have extra space
4230                  * for all three.
4231                  */
4232                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4233                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4234                         sb->s_time_gran = 1;
4235                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4236                 } else {
4237                         sb->s_time_gran = NSEC_PER_SEC;
4238                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4239                 }
4240                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4241         }
4242         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4243                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4244                         EXT4_GOOD_OLD_INODE_SIZE;
4245                 if (ext4_has_feature_extra_isize(sb)) {
4246                         unsigned v, max = (sbi->s_inode_size -
4247                                            EXT4_GOOD_OLD_INODE_SIZE);
4248
4249                         v = le16_to_cpu(es->s_want_extra_isize);
4250                         if (v > max) {
4251                                 ext4_msg(sb, KERN_ERR,
4252                                          "bad s_want_extra_isize: %d", v);
4253                                 goto failed_mount;
4254                         }
4255                         if (sbi->s_want_extra_isize < v)
4256                                 sbi->s_want_extra_isize = v;
4257
4258                         v = le16_to_cpu(es->s_min_extra_isize);
4259                         if (v > max) {
4260                                 ext4_msg(sb, KERN_ERR,
4261                                          "bad s_min_extra_isize: %d", v);
4262                                 goto failed_mount;
4263                         }
4264                         if (sbi->s_want_extra_isize < v)
4265                                 sbi->s_want_extra_isize = v;
4266                 }
4267         }
4268
4269         if (sbi->s_es->s_mount_opts[0]) {
4270                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
4271                                               sizeof(sbi->s_es->s_mount_opts),
4272                                               GFP_KERNEL);
4273                 if (!s_mount_opts)
4274                         goto failed_mount;
4275                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
4276                                    &journal_ioprio, 0)) {
4277                         ext4_msg(sb, KERN_WARNING,
4278                                  "failed to parse options in superblock: %s",
4279                                  s_mount_opts);
4280                 }
4281                 kfree(s_mount_opts);
4282         }
4283         sbi->s_def_mount_opt = sbi->s_mount_opt;
4284         if (!parse_options((char *) data, sb, &journal_devnum,
4285                            &journal_ioprio, 0))
4286                 goto failed_mount;
4287
4288 #ifdef CONFIG_UNICODE
4289         if (ext4_has_feature_casefold(sb) && !sb->s_encoding) {
4290                 const struct ext4_sb_encodings *encoding_info;
4291                 struct unicode_map *encoding;
4292                 __u16 encoding_flags;
4293
4294                 if (ext4_has_feature_encrypt(sb)) {
4295                         ext4_msg(sb, KERN_ERR,
4296                                  "Can't mount with encoding and encryption");
4297                         goto failed_mount;
4298                 }
4299
4300                 if (ext4_sb_read_encoding(es, &encoding_info,
4301                                           &encoding_flags)) {
4302                         ext4_msg(sb, KERN_ERR,
4303                                  "Encoding requested by superblock is unknown");
4304                         goto failed_mount;
4305                 }
4306
4307                 encoding = utf8_load(encoding_info->version);
4308                 if (IS_ERR(encoding)) {
4309                         ext4_msg(sb, KERN_ERR,
4310                                  "can't mount with superblock charset: %s-%s "
4311                                  "not supported by the kernel. flags: 0x%x.",
4312                                  encoding_info->name, encoding_info->version,
4313                                  encoding_flags);
4314                         goto failed_mount;
4315                 }
4316                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4317                          "%s-%s with flags 0x%hx", encoding_info->name,
4318                          encoding_info->version?:"\b", encoding_flags);
4319
4320                 sb->s_encoding = encoding;
4321                 sb->s_encoding_flags = encoding_flags;
4322         }
4323 #endif
4324
4325         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4326                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, O_DIRECT and fast_commit support!\n");
4327                 /* can't mount with both data=journal and dioread_nolock. */
4328                 clear_opt(sb, DIOREAD_NOLOCK);
4329                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4330                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4331                         ext4_msg(sb, KERN_ERR, "can't mount with "
4332                                  "both data=journal and delalloc");
4333                         goto failed_mount;
4334                 }
4335                 if (test_opt(sb, DAX_ALWAYS)) {
4336                         ext4_msg(sb, KERN_ERR, "can't mount with "
4337                                  "both data=journal and dax");
4338                         goto failed_mount;
4339                 }
4340                 if (ext4_has_feature_encrypt(sb)) {
4341                         ext4_msg(sb, KERN_WARNING,
4342                                  "encrypted files will use data=ordered "
4343                                  "instead of data journaling mode");
4344                 }
4345                 if (test_opt(sb, DELALLOC))
4346                         clear_opt(sb, DELALLOC);
4347         } else {
4348                 sb->s_iflags |= SB_I_CGROUPWB;
4349         }
4350
4351         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4352                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4353
4354         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4355             (ext4_has_compat_features(sb) ||
4356              ext4_has_ro_compat_features(sb) ||
4357              ext4_has_incompat_features(sb)))
4358                 ext4_msg(sb, KERN_WARNING,
4359                        "feature flags set on rev 0 fs, "
4360                        "running e2fsck is recommended");
4361
4362         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4363                 set_opt2(sb, HURD_COMPAT);
4364                 if (ext4_has_feature_64bit(sb)) {
4365                         ext4_msg(sb, KERN_ERR,
4366                                  "The Hurd can't support 64-bit file systems");
4367                         goto failed_mount;
4368                 }
4369
4370                 /*
4371                  * ea_inode feature uses l_i_version field which is not
4372                  * available in HURD_COMPAT mode.
4373                  */
4374                 if (ext4_has_feature_ea_inode(sb)) {
4375                         ext4_msg(sb, KERN_ERR,
4376                                  "ea_inode feature is not supported for Hurd");
4377                         goto failed_mount;
4378                 }
4379         }
4380
4381         if (IS_EXT2_SB(sb)) {
4382                 if (ext2_feature_set_ok(sb))
4383                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4384                                  "using the ext4 subsystem");
4385                 else {
4386                         /*
4387                          * If we're probing be silent, if this looks like
4388                          * it's actually an ext[34] filesystem.
4389                          */
4390                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4391                                 goto failed_mount;
4392                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4393                                  "to feature incompatibilities");
4394                         goto failed_mount;
4395                 }
4396         }
4397
4398         if (IS_EXT3_SB(sb)) {
4399                 if (ext3_feature_set_ok(sb))
4400                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4401                                  "using the ext4 subsystem");
4402                 else {
4403                         /*
4404                          * If we're probing be silent, if this looks like
4405                          * it's actually an ext4 filesystem.
4406                          */
4407                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4408                                 goto failed_mount;
4409                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4410                                  "to feature incompatibilities");
4411                         goto failed_mount;
4412                 }
4413         }
4414
4415         /*
4416          * Check feature flags regardless of the revision level, since we
4417          * previously didn't change the revision level when setting the flags,
4418          * so there is a chance incompat flags are set on a rev 0 filesystem.
4419          */
4420         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4421                 goto failed_mount;
4422
4423         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4424                 ext4_msg(sb, KERN_ERR,
4425                          "Number of reserved GDT blocks insanely large: %d",
4426                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4427                 goto failed_mount;
4428         }
4429
4430         if (bdev_dax_supported(sb->s_bdev, blocksize))
4431                 set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4432
4433         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4434                 if (ext4_has_feature_inline_data(sb)) {
4435                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4436                                         " that may contain inline data");
4437                         goto failed_mount;
4438                 }
4439                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4440                         ext4_msg(sb, KERN_ERR,
4441                                 "DAX unsupported by block device.");
4442                         goto failed_mount;
4443                 }
4444         }
4445
4446         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4447                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4448                          es->s_encryption_level);
4449                 goto failed_mount;
4450         }
4451
4452         if (sb->s_blocksize != blocksize) {
4453                 /* Validate the filesystem blocksize */
4454                 if (!sb_set_blocksize(sb, blocksize)) {
4455                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4456                                         blocksize);
4457                         goto failed_mount;
4458                 }
4459
4460                 brelse(bh);
4461                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4462                 offset = do_div(logical_sb_block, blocksize);
4463                 bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4464                 if (IS_ERR(bh)) {
4465                         ext4_msg(sb, KERN_ERR,
4466                                "Can't read superblock on 2nd try");
4467                         ret = PTR_ERR(bh);
4468                         bh = NULL;
4469                         goto failed_mount;
4470                 }
4471                 es = (struct ext4_super_block *)(bh->b_data + offset);
4472                 sbi->s_es = es;
4473                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4474                         ext4_msg(sb, KERN_ERR,
4475                                "Magic mismatch, very weird!");
4476                         goto failed_mount;
4477                 }
4478         }
4479
4480         has_huge_files = ext4_has_feature_huge_file(sb);
4481         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4482                                                       has_huge_files);
4483         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4484
4485         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4486         if (ext4_has_feature_64bit(sb)) {
4487                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4488                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4489                     !is_power_of_2(sbi->s_desc_size)) {
4490                         ext4_msg(sb, KERN_ERR,
4491                                "unsupported descriptor size %lu",
4492                                sbi->s_desc_size);
4493                         goto failed_mount;
4494                 }
4495         } else
4496                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4497
4498         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4499         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4500
4501         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4502         if (sbi->s_inodes_per_block == 0)
4503                 goto cantfind_ext4;
4504         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4505             sbi->s_inodes_per_group > blocksize * 8) {
4506                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4507                          sbi->s_inodes_per_group);
4508                 goto failed_mount;
4509         }
4510         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4511                                         sbi->s_inodes_per_block;
4512         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4513         sbi->s_sbh = bh;
4514         sbi->s_mount_state = le16_to_cpu(es->s_state);
4515         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4516         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4517
4518         for (i = 0; i < 4; i++)
4519                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4520         sbi->s_def_hash_version = es->s_def_hash_version;
4521         if (ext4_has_feature_dir_index(sb)) {
4522                 i = le32_to_cpu(es->s_flags);
4523                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4524                         sbi->s_hash_unsigned = 3;
4525                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4526 #ifdef __CHAR_UNSIGNED__
4527                         if (!sb_rdonly(sb))
4528                                 es->s_flags |=
4529                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4530                         sbi->s_hash_unsigned = 3;
4531 #else
4532                         if (!sb_rdonly(sb))
4533                                 es->s_flags |=
4534                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4535 #endif
4536                 }
4537         }
4538
4539         /* Handle clustersize */
4540         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4541         if (ext4_has_feature_bigalloc(sb)) {
4542                 if (clustersize < blocksize) {
4543                         ext4_msg(sb, KERN_ERR,
4544                                  "cluster size (%d) smaller than "
4545                                  "block size (%d)", clustersize, blocksize);
4546                         goto failed_mount;
4547                 }
4548                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4549                         le32_to_cpu(es->s_log_block_size);
4550                 sbi->s_clusters_per_group =
4551                         le32_to_cpu(es->s_clusters_per_group);
4552                 if (sbi->s_clusters_per_group > blocksize * 8) {
4553                         ext4_msg(sb, KERN_ERR,
4554                                  "#clusters per group too big: %lu",
4555                                  sbi->s_clusters_per_group);
4556                         goto failed_mount;
4557                 }
4558                 if (sbi->s_blocks_per_group !=
4559                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4560                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4561                                  "clusters per group (%lu) inconsistent",
4562                                  sbi->s_blocks_per_group,
4563                                  sbi->s_clusters_per_group);
4564                         goto failed_mount;
4565                 }
4566         } else {
4567                 if (clustersize != blocksize) {
4568                         ext4_msg(sb, KERN_ERR,
4569                                  "fragment/cluster size (%d) != "
4570                                  "block size (%d)", clustersize, blocksize);
4571                         goto failed_mount;
4572                 }
4573                 if (sbi->s_blocks_per_group > blocksize * 8) {
4574                         ext4_msg(sb, KERN_ERR,
4575                                  "#blocks per group too big: %lu",
4576                                  sbi->s_blocks_per_group);
4577                         goto failed_mount;
4578                 }
4579                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4580                 sbi->s_cluster_bits = 0;
4581         }
4582         sbi->s_cluster_ratio = clustersize / blocksize;
4583
4584         /* Do we have standard group size of clustersize * 8 blocks ? */
4585         if (sbi->s_blocks_per_group == clustersize << 3)
4586                 set_opt2(sb, STD_GROUP_SIZE);
4587
4588         /*
4589          * Test whether we have more sectors than will fit in sector_t,
4590          * and whether the max offset is addressable by the page cache.
4591          */
4592         err = generic_check_addressable(sb->s_blocksize_bits,
4593                                         ext4_blocks_count(es));
4594         if (err) {
4595                 ext4_msg(sb, KERN_ERR, "filesystem"
4596                          " too large to mount safely on this system");
4597                 goto failed_mount;
4598         }
4599
4600         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4601                 goto cantfind_ext4;
4602
4603         /* check blocks count against device size */
4604         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4605         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4606                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4607                        "exceeds size of device (%llu blocks)",
4608                        ext4_blocks_count(es), blocks_count);
4609                 goto failed_mount;
4610         }
4611
4612         /*
4613          * It makes no sense for the first data block to be beyond the end
4614          * of the filesystem.
4615          */
4616         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4617                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4618                          "block %u is beyond end of filesystem (%llu)",
4619                          le32_to_cpu(es->s_first_data_block),
4620                          ext4_blocks_count(es));
4621                 goto failed_mount;
4622         }
4623         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4624             (sbi->s_cluster_ratio == 1)) {
4625                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4626                          "block is 0 with a 1k block and cluster size");
4627                 goto failed_mount;
4628         }
4629
4630         blocks_count = (ext4_blocks_count(es) -
4631                         le32_to_cpu(es->s_first_data_block) +
4632                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4633         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4634         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4635                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4636                        "(block count %llu, first data block %u, "
4637                        "blocks per group %lu)", blocks_count,
4638                        ext4_blocks_count(es),
4639                        le32_to_cpu(es->s_first_data_block),
4640                        EXT4_BLOCKS_PER_GROUP(sb));
4641                 goto failed_mount;
4642         }
4643         sbi->s_groups_count = blocks_count;
4644         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4645                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4646         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4647             le32_to_cpu(es->s_inodes_count)) {
4648                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4649                          le32_to_cpu(es->s_inodes_count),
4650                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4651                 ret = -EINVAL;
4652                 goto failed_mount;
4653         }
4654         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4655                    EXT4_DESC_PER_BLOCK(sb);
4656         if (ext4_has_feature_meta_bg(sb)) {
4657                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4658                         ext4_msg(sb, KERN_WARNING,
4659                                  "first meta block group too large: %u "
4660                                  "(group descriptor block count %u)",
4661                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4662                         goto failed_mount;
4663                 }
4664         }
4665         rcu_assign_pointer(sbi->s_group_desc,
4666                            kvmalloc_array(db_count,
4667                                           sizeof(struct buffer_head *),
4668                                           GFP_KERNEL));
4669         if (sbi->s_group_desc == NULL) {
4670                 ext4_msg(sb, KERN_ERR, "not enough memory");
4671                 ret = -ENOMEM;
4672                 goto failed_mount;
4673         }
4674
4675         bgl_lock_init(sbi->s_blockgroup_lock);
4676
4677         /* Pre-read the descriptors into the buffer cache */
4678         for (i = 0; i < db_count; i++) {
4679                 block = descriptor_loc(sb, logical_sb_block, i);
4680                 ext4_sb_breadahead_unmovable(sb, block);
4681         }
4682
4683         for (i = 0; i < db_count; i++) {
4684                 struct buffer_head *bh;
4685
4686                 block = descriptor_loc(sb, logical_sb_block, i);
4687                 bh = ext4_sb_bread_unmovable(sb, block);
4688                 if (IS_ERR(bh)) {
4689                         ext4_msg(sb, KERN_ERR,
4690                                "can't read group descriptor %d", i);
4691                         db_count = i;
4692                         ret = PTR_ERR(bh);
4693                         goto failed_mount2;
4694                 }
4695                 rcu_read_lock();
4696                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4697                 rcu_read_unlock();
4698         }
4699         sbi->s_gdb_count = db_count;
4700         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4701                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4702                 ret = -EFSCORRUPTED;
4703                 goto failed_mount2;
4704         }
4705
4706         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4707         spin_lock_init(&sbi->s_error_lock);
4708         INIT_WORK(&sbi->s_error_work, flush_stashed_error_work);
4709
4710         /* Register extent status tree shrinker */
4711         if (ext4_es_register_shrinker(sbi))
4712                 goto failed_mount3;
4713
4714         sbi->s_stripe = ext4_get_stripe_size(sbi);
4715         sbi->s_extent_max_zeroout_kb = 32;
4716
4717         /*
4718          * set up enough so that it can read an inode
4719          */
4720         sb->s_op = &ext4_sops;
4721         sb->s_export_op = &ext4_export_ops;
4722         sb->s_xattr = ext4_xattr_handlers;
4723 #ifdef CONFIG_FS_ENCRYPTION
4724         sb->s_cop = &ext4_cryptops;
4725 #endif
4726 #ifdef CONFIG_FS_VERITY
4727         sb->s_vop = &ext4_verityops;
4728 #endif
4729 #ifdef CONFIG_QUOTA
4730         sb->dq_op = &ext4_quota_operations;
4731         if (ext4_has_feature_quota(sb))
4732                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4733         else
4734                 sb->s_qcop = &ext4_qctl_operations;
4735         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4736 #endif
4737         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4738
4739         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4740         mutex_init(&sbi->s_orphan_lock);
4741
4742         /* Initialize fast commit stuff */
4743         atomic_set(&sbi->s_fc_subtid, 0);
4744         atomic_set(&sbi->s_fc_ineligible_updates, 0);
4745         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4746         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4747         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4748         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4749         sbi->s_fc_bytes = 0;
4750         ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
4751         ext4_clear_mount_flag(sb, EXT4_MF_FC_COMMITTING);
4752         spin_lock_init(&sbi->s_fc_lock);
4753         memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4754         sbi->s_fc_replay_state.fc_regions = NULL;
4755         sbi->s_fc_replay_state.fc_regions_size = 0;
4756         sbi->s_fc_replay_state.fc_regions_used = 0;
4757         sbi->s_fc_replay_state.fc_regions_valid = 0;
4758         sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4759         sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4760         sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4761
4762         sb->s_root = NULL;
4763
4764         needs_recovery = (es->s_last_orphan != 0 ||
4765                           ext4_has_feature_journal_needs_recovery(sb));
4766
4767         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4768                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4769                         goto failed_mount3a;
4770
4771         /*
4772          * The first inode we look at is the journal inode.  Don't try
4773          * root first: it may be modified in the journal!
4774          */
4775         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4776                 err = ext4_load_journal(sb, es, journal_devnum);
4777                 if (err)
4778                         goto failed_mount3a;
4779         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4780                    ext4_has_feature_journal_needs_recovery(sb)) {
4781                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4782                        "suppressed and not mounted read-only");
4783                 goto failed_mount_wq;
4784         } else {
4785                 /* Nojournal mode, all journal mount options are illegal */
4786                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4787                         ext4_msg(sb, KERN_ERR, "can't mount with "
4788                                  "journal_checksum, fs mounted w/o journal");
4789                         goto failed_mount_wq;
4790                 }
4791                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4792                         ext4_msg(sb, KERN_ERR, "can't mount with "
4793                                  "journal_async_commit, fs mounted w/o journal");
4794                         goto failed_mount_wq;
4795                 }
4796                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4797                         ext4_msg(sb, KERN_ERR, "can't mount with "
4798                                  "commit=%lu, fs mounted w/o journal",
4799                                  sbi->s_commit_interval / HZ);
4800                         goto failed_mount_wq;
4801                 }
4802                 if (EXT4_MOUNT_DATA_FLAGS &
4803                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4804                         ext4_msg(sb, KERN_ERR, "can't mount with "
4805                                  "data=, fs mounted w/o journal");
4806                         goto failed_mount_wq;
4807                 }
4808                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4809                 clear_opt(sb, JOURNAL_CHECKSUM);
4810                 clear_opt(sb, DATA_FLAGS);
4811                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4812                 sbi->s_journal = NULL;
4813                 needs_recovery = 0;
4814                 goto no_journal;
4815         }
4816
4817         if (ext4_has_feature_64bit(sb) &&
4818             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4819                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4820                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4821                 goto failed_mount_wq;
4822         }
4823
4824         if (!set_journal_csum_feature_set(sb)) {
4825                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4826                          "feature set");
4827                 goto failed_mount_wq;
4828         }
4829
4830         if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4831                 !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4832                                           JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
4833                 ext4_msg(sb, KERN_ERR,
4834                         "Failed to set fast commit journal feature");
4835                 goto failed_mount_wq;
4836         }
4837
4838         /* We have now updated the journal if required, so we can
4839          * validate the data journaling mode. */
4840         switch (test_opt(sb, DATA_FLAGS)) {
4841         case 0:
4842                 /* No mode set, assume a default based on the journal
4843                  * capabilities: ORDERED_DATA if the journal can
4844                  * cope, else JOURNAL_DATA
4845                  */
4846                 if (jbd2_journal_check_available_features
4847                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4848                         set_opt(sb, ORDERED_DATA);
4849                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4850                 } else {
4851                         set_opt(sb, JOURNAL_DATA);
4852                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4853                 }
4854                 break;
4855
4856         case EXT4_MOUNT_ORDERED_DATA:
4857         case EXT4_MOUNT_WRITEBACK_DATA:
4858                 if (!jbd2_journal_check_available_features
4859                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4860                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4861                                "requested data journaling mode");
4862                         goto failed_mount_wq;
4863                 }
4864                 break;
4865         default:
4866                 break;
4867         }
4868
4869         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4870             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4871                 ext4_msg(sb, KERN_ERR, "can't mount with "
4872                         "journal_async_commit in data=ordered mode");
4873                 goto failed_mount_wq;
4874         }
4875
4876         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4877
4878         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4879         sbi->s_journal->j_submit_inode_data_buffers =
4880                 ext4_journal_submit_inode_data_buffers;
4881         sbi->s_journal->j_finish_inode_data_buffers =
4882                 ext4_journal_finish_inode_data_buffers;
4883
4884 no_journal:
4885         if (!test_opt(sb, NO_MBCACHE)) {
4886                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4887                 if (!sbi->s_ea_block_cache) {
4888                         ext4_msg(sb, KERN_ERR,
4889                                  "Failed to create ea_block_cache");
4890                         goto failed_mount_wq;
4891                 }
4892
4893                 if (ext4_has_feature_ea_inode(sb)) {
4894                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4895                         if (!sbi->s_ea_inode_cache) {
4896                                 ext4_msg(sb, KERN_ERR,
4897                                          "Failed to create ea_inode_cache");
4898                                 goto failed_mount_wq;
4899                         }
4900                 }
4901         }
4902
4903         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4904                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4905                 goto failed_mount_wq;
4906         }
4907
4908         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4909             !ext4_has_feature_encrypt(sb)) {
4910                 ext4_set_feature_encrypt(sb);
4911                 ext4_commit_super(sb);
4912         }
4913
4914         /*
4915          * Get the # of file system overhead blocks from the
4916          * superblock if present.
4917          */
4918         if (es->s_overhead_clusters)
4919                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4920         else {
4921                 err = ext4_calculate_overhead(sb);
4922                 if (err)
4923                         goto failed_mount_wq;
4924         }
4925
4926         /*
4927          * The maximum number of concurrent works can be high and
4928          * concurrency isn't really necessary.  Limit it to 1.
4929          */
4930         EXT4_SB(sb)->rsv_conversion_wq =
4931                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4932         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4933                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4934                 ret = -ENOMEM;
4935                 goto failed_mount4;
4936         }
4937
4938         /*
4939          * The jbd2_journal_load will have done any necessary log recovery,
4940          * so we can safely mount the rest of the filesystem now.
4941          */
4942
4943         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4944         if (IS_ERR(root)) {
4945                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4946                 ret = PTR_ERR(root);
4947                 root = NULL;
4948                 goto failed_mount4;
4949         }
4950         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4951                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4952                 iput(root);
4953                 goto failed_mount4;
4954         }
4955
4956         sb->s_root = d_make_root(root);
4957         if (!sb->s_root) {
4958                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4959                 ret = -ENOMEM;
4960                 goto failed_mount4;
4961         }
4962
4963         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4964         if (ret == -EROFS) {
4965                 sb->s_flags |= SB_RDONLY;
4966                 ret = 0;
4967         } else if (ret)
4968                 goto failed_mount4a;
4969
4970         ext4_set_resv_clusters(sb);
4971
4972         if (test_opt(sb, BLOCK_VALIDITY)) {
4973                 err = ext4_setup_system_zone(sb);
4974                 if (err) {
4975                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
4976                                  "zone (%d)", err);
4977                         goto failed_mount4a;
4978                 }
4979         }
4980         ext4_fc_replay_cleanup(sb);
4981
4982         ext4_ext_init(sb);
4983         err = ext4_mb_init(sb);
4984         if (err) {
4985                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4986                          err);
4987                 goto failed_mount5;
4988         }
4989
4990         block = ext4_count_free_clusters(sb);
4991         ext4_free_blocks_count_set(sbi->s_es,
4992                                    EXT4_C2B(sbi, block));
4993         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4994                                   GFP_KERNEL);
4995         if (!err) {
4996                 unsigned long freei = ext4_count_free_inodes(sb);
4997                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4998                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4999                                           GFP_KERNEL);
5000         }
5001         if (!err)
5002                 err = percpu_counter_init(&sbi->s_dirs_counter,
5003                                           ext4_count_dirs(sb), GFP_KERNEL);
5004         if (!err)
5005                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
5006                                           GFP_KERNEL);
5007         if (!err)
5008                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
5009
5010         if (err) {
5011                 ext4_msg(sb, KERN_ERR, "insufficient memory");
5012                 goto failed_mount6;
5013         }
5014
5015         if (ext4_has_feature_flex_bg(sb))
5016                 if (!ext4_fill_flex_info(sb)) {
5017                         ext4_msg(sb, KERN_ERR,
5018                                "unable to initialize "
5019                                "flex_bg meta info!");
5020                         goto failed_mount6;
5021                 }
5022
5023         err = ext4_register_li_request(sb, first_not_zeroed);
5024         if (err)
5025                 goto failed_mount6;
5026
5027         err = ext4_register_sysfs(sb);
5028         if (err)
5029                 goto failed_mount7;
5030
5031 #ifdef CONFIG_QUOTA
5032         /* Enable quota usage during mount. */
5033         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5034                 err = ext4_enable_quotas(sb);
5035                 if (err)
5036                         goto failed_mount8;
5037         }
5038 #endif  /* CONFIG_QUOTA */
5039
5040         /*
5041          * Save the original bdev mapping's wb_err value which could be
5042          * used to detect the metadata async write error.
5043          */
5044         spin_lock_init(&sbi->s_bdev_wb_lock);
5045         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5046                                  &sbi->s_bdev_wb_err);
5047         sb->s_bdev->bd_super = sb;
5048         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5049         ext4_orphan_cleanup(sb, es);
5050         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5051         if (needs_recovery) {
5052                 ext4_msg(sb, KERN_INFO, "recovery complete");
5053                 err = ext4_mark_recovery_complete(sb, es);
5054                 if (err)
5055                         goto failed_mount8;
5056         }
5057         if (EXT4_SB(sb)->s_journal) {
5058                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5059                         descr = " journalled data mode";
5060                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5061                         descr = " ordered data mode";
5062                 else
5063                         descr = " writeback data mode";
5064         } else
5065                 descr = "out journal";
5066
5067         if (test_opt(sb, DISCARD)) {
5068                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
5069                 if (!blk_queue_discard(q))
5070                         ext4_msg(sb, KERN_WARNING,
5071                                  "mounting with \"discard\" option, but "
5072                                  "the device does not support discard");
5073         }
5074
5075         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5076                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
5077                          "Opts: %.*s%s%s. Quota mode: %s.", descr,
5078                          (int) sizeof(sbi->s_es->s_mount_opts),
5079                          sbi->s_es->s_mount_opts,
5080                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data,
5081                          ext4_quota_mode(sb));
5082
5083         if (es->s_error_count)
5084                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5085
5086         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5087         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5088         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5089         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5090         atomic_set(&sbi->s_warning_count, 0);
5091         atomic_set(&sbi->s_msg_count, 0);
5092
5093         kfree(orig_data);
5094         return 0;
5095
5096 cantfind_ext4:
5097         if (!silent)
5098                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5099         goto failed_mount;
5100
5101 failed_mount8:
5102         ext4_unregister_sysfs(sb);
5103         kobject_put(&sbi->s_kobj);
5104 failed_mount7:
5105         ext4_unregister_li_request(sb);
5106 failed_mount6:
5107         ext4_mb_release(sb);
5108         rcu_read_lock();
5109         flex_groups = rcu_dereference(sbi->s_flex_groups);
5110         if (flex_groups) {
5111                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
5112                         kvfree(flex_groups[i]);
5113                 kvfree(flex_groups);
5114         }
5115         rcu_read_unlock();
5116         percpu_counter_destroy(&sbi->s_freeclusters_counter);
5117         percpu_counter_destroy(&sbi->s_freeinodes_counter);
5118         percpu_counter_destroy(&sbi->s_dirs_counter);
5119         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
5120         percpu_free_rwsem(&sbi->s_writepages_rwsem);
5121 failed_mount5:
5122         ext4_ext_release(sb);
5123         ext4_release_system_zone(sb);
5124 failed_mount4a:
5125         dput(sb->s_root);
5126         sb->s_root = NULL;
5127 failed_mount4:
5128         ext4_msg(sb, KERN_ERR, "mount failed");
5129         if (EXT4_SB(sb)->rsv_conversion_wq)
5130                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5131 failed_mount_wq:
5132         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5133         sbi->s_ea_inode_cache = NULL;
5134
5135         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5136         sbi->s_ea_block_cache = NULL;
5137
5138         if (sbi->s_journal) {
5139                 jbd2_journal_destroy(sbi->s_journal);
5140                 sbi->s_journal = NULL;
5141         }
5142 failed_mount3a:
5143         ext4_es_unregister_shrinker(sbi);
5144 failed_mount3:
5145         del_timer_sync(&sbi->s_err_report);
5146         flush_work(&sbi->s_error_work);
5147         if (sbi->s_mmp_tsk)
5148                 kthread_stop(sbi->s_mmp_tsk);
5149 failed_mount2:
5150         rcu_read_lock();
5151         group_desc = rcu_dereference(sbi->s_group_desc);
5152         for (i = 0; i < db_count; i++)
5153                 brelse(group_desc[i]);
5154         kvfree(group_desc);
5155         rcu_read_unlock();
5156 failed_mount:
5157         if (sbi->s_chksum_driver)
5158                 crypto_free_shash(sbi->s_chksum_driver);
5159
5160 #ifdef CONFIG_UNICODE
5161         utf8_unload(sb->s_encoding);
5162 #endif
5163
5164 #ifdef CONFIG_QUOTA
5165         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5166                 kfree(get_qf_name(sb, sbi, i));
5167 #endif
5168         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5169         ext4_blkdev_remove(sbi);
5170         brelse(bh);
5171 out_fail:
5172         sb->s_fs_info = NULL;
5173         kfree(sbi->s_blockgroup_lock);
5174 out_free_base:
5175         kfree(sbi);
5176         kfree(orig_data);
5177         fs_put_dax(dax_dev);
5178         return err ? err : ret;
5179 }
5180
5181 /*
5182  * Setup any per-fs journal parameters now.  We'll do this both on
5183  * initial mount, once the journal has been initialised but before we've
5184  * done any recovery; and again on any subsequent remount.
5185  */
5186 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5187 {
5188         struct ext4_sb_info *sbi = EXT4_SB(sb);
5189
5190         journal->j_commit_interval = sbi->s_commit_interval;
5191         journal->j_min_batch_time = sbi->s_min_batch_time;
5192         journal->j_max_batch_time = sbi->s_max_batch_time;
5193         ext4_fc_init(sb, journal);
5194
5195         write_lock(&journal->j_state_lock);
5196         if (test_opt(sb, BARRIER))
5197                 journal->j_flags |= JBD2_BARRIER;
5198         else
5199                 journal->j_flags &= ~JBD2_BARRIER;
5200         if (test_opt(sb, DATA_ERR_ABORT))
5201                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5202         else
5203                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5204         write_unlock(&journal->j_state_lock);
5205 }
5206
5207 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5208                                              unsigned int journal_inum)
5209 {
5210         struct inode *journal_inode;
5211
5212         /*
5213          * Test for the existence of a valid inode on disk.  Bad things
5214          * happen if we iget() an unused inode, as the subsequent iput()
5215          * will try to delete it.
5216          */
5217         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5218         if (IS_ERR(journal_inode)) {
5219                 ext4_msg(sb, KERN_ERR, "no journal found");
5220                 return NULL;
5221         }
5222         if (!journal_inode->i_nlink) {
5223                 make_bad_inode(journal_inode);
5224                 iput(journal_inode);
5225                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5226                 return NULL;
5227         }
5228
5229         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
5230                   journal_inode, journal_inode->i_size);
5231         if (!S_ISREG(journal_inode->i_mode)) {
5232                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5233                 iput(journal_inode);
5234                 return NULL;
5235         }
5236         return journal_inode;
5237 }
5238
5239 static journal_t *ext4_get_journal(struct super_block *sb,
5240                                    unsigned int journal_inum)
5241 {
5242         struct inode *journal_inode;
5243         journal_t *journal;
5244
5245         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5246                 return NULL;
5247
5248         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5249         if (!journal_inode)
5250                 return NULL;
5251
5252         journal = jbd2_journal_init_inode(journal_inode);
5253         if (!journal) {
5254                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5255                 iput(journal_inode);
5256                 return NULL;
5257         }
5258         journal->j_private = sb;
5259         ext4_init_journal_params(sb, journal);
5260         return journal;
5261 }
5262
5263 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5264                                        dev_t j_dev)
5265 {
5266         struct buffer_head *bh;
5267         journal_t *journal;
5268         ext4_fsblk_t start;
5269         ext4_fsblk_t len;
5270         int hblock, blocksize;
5271         ext4_fsblk_t sb_block;
5272         unsigned long offset;
5273         struct ext4_super_block *es;
5274         struct block_device *bdev;
5275
5276         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5277                 return NULL;
5278
5279         bdev = ext4_blkdev_get(j_dev, sb);
5280         if (bdev == NULL)
5281                 return NULL;
5282
5283         blocksize = sb->s_blocksize;
5284         hblock = bdev_logical_block_size(bdev);
5285         if (blocksize < hblock) {
5286                 ext4_msg(sb, KERN_ERR,
5287                         "blocksize too small for journal device");
5288                 goto out_bdev;
5289         }
5290
5291         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5292         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5293         set_blocksize(bdev, blocksize);
5294         if (!(bh = __bread(bdev, sb_block, blocksize))) {
5295                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5296                        "external journal");
5297                 goto out_bdev;
5298         }
5299
5300         es = (struct ext4_super_block *) (bh->b_data + offset);
5301         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5302             !(le32_to_cpu(es->s_feature_incompat) &
5303               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5304                 ext4_msg(sb, KERN_ERR, "external journal has "
5305                                         "bad superblock");
5306                 brelse(bh);
5307                 goto out_bdev;
5308         }
5309
5310         if ((le32_to_cpu(es->s_feature_ro_compat) &
5311              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5312             es->s_checksum != ext4_superblock_csum(sb, es)) {
5313                 ext4_msg(sb, KERN_ERR, "external journal has "
5314                                        "corrupt superblock");
5315                 brelse(bh);
5316                 goto out_bdev;
5317         }
5318
5319         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5320                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5321                 brelse(bh);
5322                 goto out_bdev;
5323         }
5324
5325         len = ext4_blocks_count(es);
5326         start = sb_block + 1;
5327         brelse(bh);     /* we're done with the superblock */
5328
5329         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5330                                         start, len, blocksize);
5331         if (!journal) {
5332                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5333                 goto out_bdev;
5334         }
5335         journal->j_private = sb;
5336         if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
5337                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5338                 goto out_journal;
5339         }
5340         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5341                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5342                                         "user (unsupported) - %d",
5343                         be32_to_cpu(journal->j_superblock->s_nr_users));
5344                 goto out_journal;
5345         }
5346         EXT4_SB(sb)->s_journal_bdev = bdev;
5347         ext4_init_journal_params(sb, journal);
5348         return journal;
5349
5350 out_journal:
5351         jbd2_journal_destroy(journal);
5352 out_bdev:
5353         ext4_blkdev_put(bdev);
5354         return NULL;
5355 }
5356
5357 static int ext4_load_journal(struct super_block *sb,
5358                              struct ext4_super_block *es,
5359                              unsigned long journal_devnum)
5360 {
5361         journal_t *journal;
5362         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5363         dev_t journal_dev;
5364         int err = 0;
5365         int really_read_only;
5366         int journal_dev_ro;
5367
5368         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5369                 return -EFSCORRUPTED;
5370
5371         if (journal_devnum &&
5372             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5373                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5374                         "numbers have changed");
5375                 journal_dev = new_decode_dev(journal_devnum);
5376         } else
5377                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5378
5379         if (journal_inum && journal_dev) {
5380                 ext4_msg(sb, KERN_ERR,
5381                          "filesystem has both journal inode and journal device!");
5382                 return -EINVAL;
5383         }
5384
5385         if (journal_inum) {
5386                 journal = ext4_get_journal(sb, journal_inum);
5387                 if (!journal)
5388                         return -EINVAL;
5389         } else {
5390                 journal = ext4_get_dev_journal(sb, journal_dev);
5391                 if (!journal)
5392                         return -EINVAL;
5393         }
5394
5395         journal_dev_ro = bdev_read_only(journal->j_dev);
5396         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5397
5398         if (journal_dev_ro && !sb_rdonly(sb)) {
5399                 ext4_msg(sb, KERN_ERR,
5400                          "journal device read-only, try mounting with '-o ro'");
5401                 err = -EROFS;
5402                 goto err_out;
5403         }
5404
5405         /*
5406          * Are we loading a blank journal or performing recovery after a
5407          * crash?  For recovery, we need to check in advance whether we
5408          * can get read-write access to the device.
5409          */
5410         if (ext4_has_feature_journal_needs_recovery(sb)) {
5411                 if (sb_rdonly(sb)) {
5412                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5413                                         "required on readonly filesystem");
5414                         if (really_read_only) {
5415                                 ext4_msg(sb, KERN_ERR, "write access "
5416                                         "unavailable, cannot proceed "
5417                                         "(try mounting with noload)");
5418                                 err = -EROFS;
5419                                 goto err_out;
5420                         }
5421                         ext4_msg(sb, KERN_INFO, "write access will "
5422                                "be enabled during recovery");
5423                 }
5424         }
5425
5426         if (!(journal->j_flags & JBD2_BARRIER))
5427                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5428
5429         if (!ext4_has_feature_journal_needs_recovery(sb))
5430                 err = jbd2_journal_wipe(journal, !really_read_only);
5431         if (!err) {
5432                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5433                 if (save)
5434                         memcpy(save, ((char *) es) +
5435                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5436                 err = jbd2_journal_load(journal);
5437                 if (save)
5438                         memcpy(((char *) es) + EXT4_S_ERR_START,
5439                                save, EXT4_S_ERR_LEN);
5440                 kfree(save);
5441         }
5442
5443         if (err) {
5444                 ext4_msg(sb, KERN_ERR, "error loading journal");
5445                 goto err_out;
5446         }
5447
5448         EXT4_SB(sb)->s_journal = journal;
5449         err = ext4_clear_journal_err(sb, es);
5450         if (err) {
5451                 EXT4_SB(sb)->s_journal = NULL;
5452                 jbd2_journal_destroy(journal);
5453                 return err;
5454         }
5455
5456         if (!really_read_only && journal_devnum &&
5457             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5458                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5459
5460                 /* Make sure we flush the recovery flag to disk. */
5461                 ext4_commit_super(sb);
5462         }
5463
5464         return 0;
5465
5466 err_out:
5467         jbd2_journal_destroy(journal);
5468         return err;
5469 }
5470
5471 /* Copy state of EXT4_SB(sb) into buffer for on-disk superblock */
5472 static void ext4_update_super(struct super_block *sb)
5473 {
5474         struct ext4_sb_info *sbi = EXT4_SB(sb);
5475         struct ext4_super_block *es = sbi->s_es;
5476         struct buffer_head *sbh = sbi->s_sbh;
5477
5478         lock_buffer(sbh);
5479         /*
5480          * If the file system is mounted read-only, don't update the
5481          * superblock write time.  This avoids updating the superblock
5482          * write time when we are mounting the root file system
5483          * read/only but we need to replay the journal; at that point,
5484          * for people who are east of GMT and who make their clock
5485          * tick in localtime for Windows bug-for-bug compatibility,
5486          * the clock is set in the future, and this will cause e2fsck
5487          * to complain and force a full file system check.
5488          */
5489         if (!(sb->s_flags & SB_RDONLY))
5490                 ext4_update_tstamp(es, s_wtime);
5491         es->s_kbytes_written =
5492                 cpu_to_le64(sbi->s_kbytes_written +
5493                     ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
5494                       sbi->s_sectors_written_start) >> 1));
5495         if (percpu_counter_initialized(&sbi->s_freeclusters_counter))
5496                 ext4_free_blocks_count_set(es,
5497                         EXT4_C2B(sbi, percpu_counter_sum_positive(
5498                                 &sbi->s_freeclusters_counter)));
5499         if (percpu_counter_initialized(&sbi->s_freeinodes_counter))
5500                 es->s_free_inodes_count =
5501                         cpu_to_le32(percpu_counter_sum_positive(
5502                                 &sbi->s_freeinodes_counter));
5503         /* Copy error information to the on-disk superblock */
5504         spin_lock(&sbi->s_error_lock);
5505         if (sbi->s_add_error_count > 0) {
5506                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5507                 if (!es->s_first_error_time && !es->s_first_error_time_hi) {
5508                         __ext4_update_tstamp(&es->s_first_error_time,
5509                                              &es->s_first_error_time_hi,
5510                                              sbi->s_first_error_time);
5511                         strncpy(es->s_first_error_func, sbi->s_first_error_func,
5512                                 sizeof(es->s_first_error_func));
5513                         es->s_first_error_line =
5514                                 cpu_to_le32(sbi->s_first_error_line);
5515                         es->s_first_error_ino =
5516                                 cpu_to_le32(sbi->s_first_error_ino);
5517                         es->s_first_error_block =
5518                                 cpu_to_le64(sbi->s_first_error_block);
5519                         es->s_first_error_errcode =
5520                                 ext4_errno_to_code(sbi->s_first_error_code);
5521                 }
5522                 __ext4_update_tstamp(&es->s_last_error_time,
5523                                      &es->s_last_error_time_hi,
5524                                      sbi->s_last_error_time);
5525                 strncpy(es->s_last_error_func, sbi->s_last_error_func,
5526                         sizeof(es->s_last_error_func));
5527                 es->s_last_error_line = cpu_to_le32(sbi->s_last_error_line);
5528                 es->s_last_error_ino = cpu_to_le32(sbi->s_last_error_ino);
5529                 es->s_last_error_block = cpu_to_le64(sbi->s_last_error_block);
5530                 es->s_last_error_errcode =
5531                                 ext4_errno_to_code(sbi->s_last_error_code);
5532                 /*
5533                  * Start the daily error reporting function if it hasn't been
5534                  * started already
5535                  */
5536                 if (!es->s_error_count)
5537                         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
5538                 le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
5539                 sbi->s_add_error_count = 0;
5540         }
5541         spin_unlock(&sbi->s_error_lock);
5542
5543         ext4_superblock_csum_set(sb);
5544         unlock_buffer(sbh);
5545 }
5546
5547 static int ext4_commit_super(struct super_block *sb)
5548 {
5549         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5550         int error = 0;
5551
5552         if (!sbh || block_device_ejected(sb))
5553                 return error;
5554
5555         ext4_update_super(sb);
5556
5557         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5558                 /*
5559                  * Oh, dear.  A previous attempt to write the
5560                  * superblock failed.  This could happen because the
5561                  * USB device was yanked out.  Or it could happen to
5562                  * be a transient write error and maybe the block will
5563                  * be remapped.  Nothing we can do but to retry the
5564                  * write and hope for the best.
5565                  */
5566                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5567                        "superblock detected");
5568                 clear_buffer_write_io_error(sbh);
5569                 set_buffer_uptodate(sbh);
5570         }
5571         BUFFER_TRACE(sbh, "marking dirty");
5572         mark_buffer_dirty(sbh);
5573         error = __sync_dirty_buffer(sbh,
5574                 REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5575         if (buffer_write_io_error(sbh)) {
5576                 ext4_msg(sb, KERN_ERR, "I/O error while writing "
5577                        "superblock");
5578                 clear_buffer_write_io_error(sbh);
5579                 set_buffer_uptodate(sbh);
5580         }
5581         return error;
5582 }
5583
5584 /*
5585  * Have we just finished recovery?  If so, and if we are mounting (or
5586  * remounting) the filesystem readonly, then we will end up with a
5587  * consistent fs on disk.  Record that fact.
5588  */
5589 static int ext4_mark_recovery_complete(struct super_block *sb,
5590                                        struct ext4_super_block *es)
5591 {
5592         int err;
5593         journal_t *journal = EXT4_SB(sb)->s_journal;
5594
5595         if (!ext4_has_feature_journal(sb)) {
5596                 if (journal != NULL) {
5597                         ext4_error(sb, "Journal got removed while the fs was "
5598                                    "mounted!");
5599                         return -EFSCORRUPTED;
5600                 }
5601                 return 0;
5602         }
5603         jbd2_journal_lock_updates(journal);
5604         err = jbd2_journal_flush(journal);
5605         if (err < 0)
5606                 goto out;
5607
5608         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5609                 ext4_clear_feature_journal_needs_recovery(sb);
5610                 ext4_commit_super(sb);
5611         }
5612 out:
5613         jbd2_journal_unlock_updates(journal);
5614         return err;
5615 }
5616
5617 /*
5618  * If we are mounting (or read-write remounting) a filesystem whose journal
5619  * has recorded an error from a previous lifetime, move that error to the
5620  * main filesystem now.
5621  */
5622 static int ext4_clear_journal_err(struct super_block *sb,
5623                                    struct ext4_super_block *es)
5624 {
5625         journal_t *journal;
5626         int j_errno;
5627         const char *errstr;
5628
5629         if (!ext4_has_feature_journal(sb)) {
5630                 ext4_error(sb, "Journal got removed while the fs was mounted!");
5631                 return -EFSCORRUPTED;
5632         }
5633
5634         journal = EXT4_SB(sb)->s_journal;
5635
5636         /*
5637          * Now check for any error status which may have been recorded in the
5638          * journal by a prior ext4_error() or ext4_abort()
5639          */
5640
5641         j_errno = jbd2_journal_errno(journal);
5642         if (j_errno) {
5643                 char nbuf[16];
5644
5645                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5646                 ext4_warning(sb, "Filesystem error recorded "
5647                              "from previous mount: %s", errstr);
5648                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5649
5650                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5651                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5652                 ext4_commit_super(sb);
5653
5654                 jbd2_journal_clear_err(journal);
5655                 jbd2_journal_update_sb_errno(journal);
5656         }
5657         return 0;
5658 }
5659
5660 /*
5661  * Force the running and committing transactions to commit,
5662  * and wait on the commit.
5663  */
5664 int ext4_force_commit(struct super_block *sb)
5665 {
5666         journal_t *journal;
5667
5668         if (sb_rdonly(sb))
5669                 return 0;
5670
5671         journal = EXT4_SB(sb)->s_journal;
5672         return ext4_journal_force_commit(journal);
5673 }
5674
5675 static int ext4_sync_fs(struct super_block *sb, int wait)
5676 {
5677         int ret = 0;
5678         tid_t target;
5679         bool needs_barrier = false;
5680         struct ext4_sb_info *sbi = EXT4_SB(sb);
5681
5682         if (unlikely(ext4_forced_shutdown(sbi)))
5683                 return 0;
5684
5685         trace_ext4_sync_fs(sb, wait);
5686         flush_workqueue(sbi->rsv_conversion_wq);
5687         /*
5688          * Writeback quota in non-journalled quota case - journalled quota has
5689          * no dirty dquots
5690          */
5691         dquot_writeback_dquots(sb, -1);
5692         /*
5693          * Data writeback is possible w/o journal transaction, so barrier must
5694          * being sent at the end of the function. But we can skip it if
5695          * transaction_commit will do it for us.
5696          */
5697         if (sbi->s_journal) {
5698                 target = jbd2_get_latest_transaction(sbi->s_journal);
5699                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5700                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5701                         needs_barrier = true;
5702
5703                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5704                         if (wait)
5705                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5706                                                            target);
5707                 }
5708         } else if (wait && test_opt(sb, BARRIER))
5709                 needs_barrier = true;
5710         if (needs_barrier) {
5711                 int err;
5712                 err = blkdev_issue_flush(sb->s_bdev);
5713                 if (!ret)
5714                         ret = err;
5715         }
5716
5717         return ret;
5718 }
5719
5720 /*
5721  * LVM calls this function before a (read-only) snapshot is created.  This
5722  * gives us a chance to flush the journal completely and mark the fs clean.
5723  *
5724  * Note that only this function cannot bring a filesystem to be in a clean
5725  * state independently. It relies on upper layer to stop all data & metadata
5726  * modifications.
5727  */
5728 static int ext4_freeze(struct super_block *sb)
5729 {
5730         int error = 0;
5731         journal_t *journal;
5732
5733         if (sb_rdonly(sb))
5734                 return 0;
5735
5736         journal = EXT4_SB(sb)->s_journal;
5737
5738         if (journal) {
5739                 /* Now we set up the journal barrier. */
5740                 jbd2_journal_lock_updates(journal);
5741
5742                 /*
5743                  * Don't clear the needs_recovery flag if we failed to
5744                  * flush the journal.
5745                  */
5746                 error = jbd2_journal_flush(journal);
5747                 if (error < 0)
5748                         goto out;
5749
5750                 /* Journal blocked and flushed, clear needs_recovery flag. */
5751                 ext4_clear_feature_journal_needs_recovery(sb);
5752         }
5753
5754         error = ext4_commit_super(sb);
5755 out:
5756         if (journal)
5757                 /* we rely on upper layer to stop further updates */
5758                 jbd2_journal_unlock_updates(journal);
5759         return error;
5760 }
5761
5762 /*
5763  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5764  * flag here, even though the filesystem is not technically dirty yet.
5765  */
5766 static int ext4_unfreeze(struct super_block *sb)
5767 {
5768         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5769                 return 0;
5770
5771         if (EXT4_SB(sb)->s_journal) {
5772                 /* Reset the needs_recovery flag before the fs is unlocked. */
5773                 ext4_set_feature_journal_needs_recovery(sb);
5774         }
5775
5776         ext4_commit_super(sb);
5777         return 0;
5778 }
5779
5780 /*
5781  * Structure to save mount options for ext4_remount's benefit
5782  */
5783 struct ext4_mount_options {
5784         unsigned long s_mount_opt;
5785         unsigned long s_mount_opt2;
5786         kuid_t s_resuid;
5787         kgid_t s_resgid;
5788         unsigned long s_commit_interval;
5789         u32 s_min_batch_time, s_max_batch_time;
5790 #ifdef CONFIG_QUOTA
5791         int s_jquota_fmt;
5792         char *s_qf_names[EXT4_MAXQUOTAS];
5793 #endif
5794 };
5795
5796 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5797 {
5798         struct ext4_super_block *es;
5799         struct ext4_sb_info *sbi = EXT4_SB(sb);
5800         unsigned long old_sb_flags, vfs_flags;
5801         struct ext4_mount_options old_opts;
5802         int enable_quota = 0;
5803         ext4_group_t g;
5804         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5805         int err = 0;
5806 #ifdef CONFIG_QUOTA
5807         int i, j;
5808         char *to_free[EXT4_MAXQUOTAS];
5809 #endif
5810         char *orig_data = kstrdup(data, GFP_KERNEL);
5811
5812         if (data && !orig_data)
5813                 return -ENOMEM;
5814
5815         /* Store the original options */
5816         old_sb_flags = sb->s_flags;
5817         old_opts.s_mount_opt = sbi->s_mount_opt;
5818         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5819         old_opts.s_resuid = sbi->s_resuid;
5820         old_opts.s_resgid = sbi->s_resgid;
5821         old_opts.s_commit_interval = sbi->s_commit_interval;
5822         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5823         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5824 #ifdef CONFIG_QUOTA
5825         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5826         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5827                 if (sbi->s_qf_names[i]) {
5828                         char *qf_name = get_qf_name(sb, sbi, i);
5829
5830                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5831                         if (!old_opts.s_qf_names[i]) {
5832                                 for (j = 0; j < i; j++)
5833                                         kfree(old_opts.s_qf_names[j]);
5834                                 kfree(orig_data);
5835                                 return -ENOMEM;
5836                         }
5837                 } else
5838                         old_opts.s_qf_names[i] = NULL;
5839 #endif
5840         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5841                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5842
5843         /*
5844          * Some options can be enabled by ext4 and/or by VFS mount flag
5845          * either way we need to make sure it matches in both *flags and
5846          * s_flags. Copy those selected flags from *flags to s_flags
5847          */
5848         vfs_flags = SB_LAZYTIME | SB_I_VERSION;
5849         sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags);
5850
5851         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5852                 err = -EINVAL;
5853                 goto restore_opts;
5854         }
5855
5856         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5857             test_opt(sb, JOURNAL_CHECKSUM)) {
5858                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5859                          "during remount not supported; ignoring");
5860                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5861         }
5862
5863         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5864                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5865                         ext4_msg(sb, KERN_ERR, "can't mount with "
5866                                  "both data=journal and delalloc");
5867                         err = -EINVAL;
5868                         goto restore_opts;
5869                 }
5870                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5871                         ext4_msg(sb, KERN_ERR, "can't mount with "
5872                                  "both data=journal and dioread_nolock");
5873                         err = -EINVAL;
5874                         goto restore_opts;
5875                 }
5876         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5877                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5878                         ext4_msg(sb, KERN_ERR, "can't mount with "
5879                                 "journal_async_commit in data=ordered mode");
5880                         err = -EINVAL;
5881                         goto restore_opts;
5882                 }
5883         }
5884
5885         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5886                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5887                 err = -EINVAL;
5888                 goto restore_opts;
5889         }
5890
5891         if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED))
5892                 ext4_abort(sb, EXT4_ERR_ESHUTDOWN, "Abort forced by user");
5893
5894         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5895                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5896
5897         es = sbi->s_es;
5898
5899         if (sbi->s_journal) {
5900                 ext4_init_journal_params(sb, sbi->s_journal);
5901                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5902         }
5903
5904         /* Flush outstanding errors before changing fs state */
5905         flush_work(&sbi->s_error_work);
5906
5907         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5908                 if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED)) {
5909                         err = -EROFS;
5910                         goto restore_opts;
5911                 }
5912
5913                 if (*flags & SB_RDONLY) {
5914                         err = sync_filesystem(sb);
5915                         if (err < 0)
5916                                 goto restore_opts;
5917                         err = dquot_suspend(sb, -1);
5918                         if (err < 0)
5919                                 goto restore_opts;
5920
5921                         /*
5922                          * First of all, the unconditional stuff we have to do
5923                          * to disable replay of the journal when we next remount
5924                          */
5925                         sb->s_flags |= SB_RDONLY;
5926
5927                         /*
5928                          * OK, test if we are remounting a valid rw partition
5929                          * readonly, and if so set the rdonly flag and then
5930                          * mark the partition as valid again.
5931                          */
5932                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5933                             (sbi->s_mount_state & EXT4_VALID_FS))
5934                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5935
5936                         if (sbi->s_journal) {
5937                                 /*
5938                                  * We let remount-ro finish even if marking fs
5939                                  * as clean failed...
5940                                  */
5941                                 ext4_mark_recovery_complete(sb, es);
5942                         }
5943                         if (sbi->s_mmp_tsk)
5944                                 kthread_stop(sbi->s_mmp_tsk);
5945                 } else {
5946                         /* Make sure we can mount this feature set readwrite */
5947                         if (ext4_has_feature_readonly(sb) ||
5948                             !ext4_feature_set_ok(sb, 0)) {
5949                                 err = -EROFS;
5950                                 goto restore_opts;
5951                         }
5952                         /*
5953                          * Make sure the group descriptor checksums
5954                          * are sane.  If they aren't, refuse to remount r/w.
5955                          */
5956                         for (g = 0; g < sbi->s_groups_count; g++) {
5957                                 struct ext4_group_desc *gdp =
5958                                         ext4_get_group_desc(sb, g, NULL);
5959
5960                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5961                                         ext4_msg(sb, KERN_ERR,
5962                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5963                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5964                                                le16_to_cpu(gdp->bg_checksum));
5965                                         err = -EFSBADCRC;
5966                                         goto restore_opts;
5967                                 }
5968                         }
5969
5970                         /*
5971                          * If we have an unprocessed orphan list hanging
5972                          * around from a previously readonly bdev mount,
5973                          * require a full umount/remount for now.
5974                          */
5975                         if (es->s_last_orphan) {
5976                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5977                                        "remount RDWR because of unprocessed "
5978                                        "orphan inode list.  Please "
5979                                        "umount/remount instead");
5980                                 err = -EINVAL;
5981                                 goto restore_opts;
5982                         }
5983
5984                         /*
5985                          * Mounting a RDONLY partition read-write, so reread
5986                          * and store the current valid flag.  (It may have
5987                          * been changed by e2fsck since we originally mounted
5988                          * the partition.)
5989                          */
5990                         if (sbi->s_journal) {
5991                                 err = ext4_clear_journal_err(sb, es);
5992                                 if (err)
5993                                         goto restore_opts;
5994                         }
5995                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5996
5997                         err = ext4_setup_super(sb, es, 0);
5998                         if (err)
5999                                 goto restore_opts;
6000
6001                         sb->s_flags &= ~SB_RDONLY;
6002                         if (ext4_has_feature_mmp(sb))
6003                                 if (ext4_multi_mount_protect(sb,
6004                                                 le64_to_cpu(es->s_mmp_block))) {
6005                                         err = -EROFS;
6006                                         goto restore_opts;
6007                                 }
6008                         enable_quota = 1;
6009                 }
6010         }
6011
6012         /*
6013          * Reinitialize lazy itable initialization thread based on
6014          * current settings
6015          */
6016         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
6017                 ext4_unregister_li_request(sb);
6018         else {
6019                 ext4_group_t first_not_zeroed;
6020                 first_not_zeroed = ext4_has_uninit_itable(sb);
6021                 ext4_register_li_request(sb, first_not_zeroed);
6022         }
6023
6024         /*
6025          * Handle creation of system zone data early because it can fail.
6026          * Releasing of existing data is done when we are sure remount will
6027          * succeed.
6028          */
6029         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6030                 err = ext4_setup_system_zone(sb);
6031                 if (err)
6032                         goto restore_opts;
6033         }
6034
6035         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6036                 err = ext4_commit_super(sb);
6037                 if (err)
6038                         goto restore_opts;
6039         }
6040
6041 #ifdef CONFIG_QUOTA
6042         /* Release old quota file names */
6043         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6044                 kfree(old_opts.s_qf_names[i]);
6045         if (enable_quota) {
6046                 if (sb_any_quota_suspended(sb))
6047                         dquot_resume(sb, -1);
6048                 else if (ext4_has_feature_quota(sb)) {
6049                         err = ext4_enable_quotas(sb);
6050                         if (err)
6051                                 goto restore_opts;
6052                 }
6053         }
6054 #endif
6055         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6056                 ext4_release_system_zone(sb);
6057
6058         /*
6059          * Some options can be enabled by ext4 and/or by VFS mount flag
6060          * either way we need to make sure it matches in both *flags and
6061          * s_flags. Copy those selected flags from s_flags to *flags
6062          */
6063         *flags = (*flags & ~vfs_flags) | (sb->s_flags & vfs_flags);
6064
6065         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s. Quota mode: %s.",
6066                  orig_data, ext4_quota_mode(sb));
6067         kfree(orig_data);
6068         return 0;
6069
6070 restore_opts:
6071         sb->s_flags = old_sb_flags;
6072         sbi->s_mount_opt = old_opts.s_mount_opt;
6073         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6074         sbi->s_resuid = old_opts.s_resuid;
6075         sbi->s_resgid = old_opts.s_resgid;
6076         sbi->s_commit_interval = old_opts.s_commit_interval;
6077         sbi->s_min_batch_time = old_opts.s_min_batch_time;
6078         sbi->s_max_batch_time = old_opts.s_max_batch_time;
6079         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6080                 ext4_release_system_zone(sb);
6081 #ifdef CONFIG_QUOTA
6082         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6083         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6084                 to_free[i] = get_qf_name(sb, sbi, i);
6085                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6086         }
6087         synchronize_rcu();
6088         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6089                 kfree(to_free[i]);
6090 #endif
6091         kfree(orig_data);
6092         return err;
6093 }
6094
6095 #ifdef CONFIG_QUOTA
6096 static int ext4_statfs_project(struct super_block *sb,
6097                                kprojid_t projid, struct kstatfs *buf)
6098 {
6099         struct kqid qid;
6100         struct dquot *dquot;
6101         u64 limit;
6102         u64 curblock;
6103
6104         qid = make_kqid_projid(projid);
6105         dquot = dqget(sb, qid);
6106         if (IS_ERR(dquot))
6107                 return PTR_ERR(dquot);
6108         spin_lock(&dquot->dq_dqb_lock);
6109
6110         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6111                              dquot->dq_dqb.dqb_bhardlimit);
6112         limit >>= sb->s_blocksize_bits;
6113
6114         if (limit && buf->f_blocks > limit) {
6115                 curblock = (dquot->dq_dqb.dqb_curspace +
6116                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6117                 buf->f_blocks = limit;
6118                 buf->f_bfree = buf->f_bavail =
6119                         (buf->f_blocks > curblock) ?
6120                          (buf->f_blocks - curblock) : 0;
6121         }
6122
6123         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6124                              dquot->dq_dqb.dqb_ihardlimit);
6125         if (limit && buf->f_files > limit) {
6126                 buf->f_files = limit;
6127                 buf->f_ffree =
6128                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6129                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6130         }
6131
6132         spin_unlock(&dquot->dq_dqb_lock);
6133         dqput(dquot);
6134         return 0;
6135 }
6136 #endif
6137
6138 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6139 {
6140         struct super_block *sb = dentry->d_sb;
6141         struct ext4_sb_info *sbi = EXT4_SB(sb);
6142         struct ext4_super_block *es = sbi->s_es;
6143         ext4_fsblk_t overhead = 0, resv_blocks;
6144         u64 fsid;
6145         s64 bfree;
6146         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6147
6148         if (!test_opt(sb, MINIX_DF))
6149                 overhead = sbi->s_overhead;
6150
6151         buf->f_type = EXT4_SUPER_MAGIC;
6152         buf->f_bsize = sb->s_blocksize;
6153         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6154         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6155                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6156         /* prevent underflow in case that few free space is available */
6157         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6158         buf->f_bavail = buf->f_bfree -
6159                         (ext4_r_blocks_count(es) + resv_blocks);
6160         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6161                 buf->f_bavail = 0;
6162         buf->f_files = le32_to_cpu(es->s_inodes_count);
6163         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6164         buf->f_namelen = EXT4_NAME_LEN;
6165         fsid = le64_to_cpup((void *)es->s_uuid) ^
6166                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
6167         buf->f_fsid = u64_to_fsid(fsid);
6168
6169 #ifdef CONFIG_QUOTA
6170         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6171             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6172                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6173 #endif
6174         return 0;
6175 }
6176
6177
6178 #ifdef CONFIG_QUOTA
6179
6180 /*
6181  * Helper functions so that transaction is started before we acquire dqio_sem
6182  * to keep correct lock ordering of transaction > dqio_sem
6183  */
6184 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6185 {
6186         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6187 }
6188
6189 static int ext4_write_dquot(struct dquot *dquot)
6190 {
6191         int ret, err;
6192         handle_t *handle;
6193         struct inode *inode;
6194
6195         inode = dquot_to_inode(dquot);
6196         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6197                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6198         if (IS_ERR(handle))
6199                 return PTR_ERR(handle);
6200         ret = dquot_commit(dquot);
6201         err = ext4_journal_stop(handle);
6202         if (!ret)
6203                 ret = err;
6204         return ret;
6205 }
6206
6207 static int ext4_acquire_dquot(struct dquot *dquot)
6208 {
6209         int ret, err;
6210         handle_t *handle;
6211
6212         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6213                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6214         if (IS_ERR(handle))
6215                 return PTR_ERR(handle);
6216         ret = dquot_acquire(dquot);
6217         err = ext4_journal_stop(handle);
6218         if (!ret)
6219                 ret = err;
6220         return ret;
6221 }
6222
6223 static int ext4_release_dquot(struct dquot *dquot)
6224 {
6225         int ret, err;
6226         handle_t *handle;
6227
6228         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6229                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6230         if (IS_ERR(handle)) {
6231                 /* Release dquot anyway to avoid endless cycle in dqput() */
6232                 dquot_release(dquot);
6233                 return PTR_ERR(handle);
6234         }
6235         ret = dquot_release(dquot);
6236         err = ext4_journal_stop(handle);
6237         if (!ret)
6238                 ret = err;
6239         return ret;
6240 }
6241
6242 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6243 {
6244         struct super_block *sb = dquot->dq_sb;
6245
6246         if (ext4_is_quota_journalled(sb)) {
6247                 dquot_mark_dquot_dirty(dquot);
6248                 return ext4_write_dquot(dquot);
6249         } else {
6250                 return dquot_mark_dquot_dirty(dquot);
6251         }
6252 }
6253
6254 static int ext4_write_info(struct super_block *sb, int type)
6255 {
6256         int ret, err;
6257         handle_t *handle;
6258
6259         /* Data block + inode block */
6260         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
6261         if (IS_ERR(handle))
6262                 return PTR_ERR(handle);
6263         ret = dquot_commit_info(sb, type);
6264         err = ext4_journal_stop(handle);
6265         if (!ret)
6266                 ret = err;
6267         return ret;
6268 }
6269
6270 /*
6271  * Turn on quotas during mount time - we need to find
6272  * the quota file and such...
6273  */
6274 static int ext4_quota_on_mount(struct super_block *sb, int type)
6275 {
6276         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
6277                                         EXT4_SB(sb)->s_jquota_fmt, type);
6278 }
6279
6280 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6281 {
6282         struct ext4_inode_info *ei = EXT4_I(inode);
6283
6284         /* The first argument of lockdep_set_subclass has to be
6285          * *exactly* the same as the argument to init_rwsem() --- in
6286          * this case, in init_once() --- or lockdep gets unhappy
6287          * because the name of the lock is set using the
6288          * stringification of the argument to init_rwsem().
6289          */
6290         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6291         lockdep_set_subclass(&ei->i_data_sem, subclass);
6292 }
6293
6294 /*
6295  * Standard function to be called on quota_on
6296  */
6297 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6298                          const struct path *path)
6299 {
6300         int err;
6301
6302         if (!test_opt(sb, QUOTA))
6303                 return -EINVAL;
6304
6305         /* Quotafile not on the same filesystem? */
6306         if (path->dentry->d_sb != sb)
6307                 return -EXDEV;
6308
6309         /* Quota already enabled for this file? */
6310         if (IS_NOQUOTA(d_inode(path->dentry)))
6311                 return -EBUSY;
6312
6313         /* Journaling quota? */
6314         if (EXT4_SB(sb)->s_qf_names[type]) {
6315                 /* Quotafile not in fs root? */
6316                 if (path->dentry->d_parent != sb->s_root)
6317                         ext4_msg(sb, KERN_WARNING,
6318                                 "Quota file not on filesystem root. "
6319                                 "Journaled quota will not work");
6320                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6321         } else {
6322                 /*
6323                  * Clear the flag just in case mount options changed since
6324                  * last time.
6325                  */
6326                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6327         }
6328
6329         /*
6330          * When we journal data on quota file, we have to flush journal to see
6331          * all updates to the file when we bypass pagecache...
6332          */
6333         if (EXT4_SB(sb)->s_journal &&
6334             ext4_should_journal_data(d_inode(path->dentry))) {
6335                 /*
6336                  * We don't need to lock updates but journal_flush() could
6337                  * otherwise be livelocked...
6338                  */
6339                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6340                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
6341                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6342                 if (err)
6343                         return err;
6344         }
6345
6346         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6347         err = dquot_quota_on(sb, type, format_id, path);
6348         if (err) {
6349                 lockdep_set_quota_inode(path->dentry->d_inode,
6350                                              I_DATA_SEM_NORMAL);
6351         } else {
6352                 struct inode *inode = d_inode(path->dentry);
6353                 handle_t *handle;
6354
6355                 /*
6356                  * Set inode flags to prevent userspace from messing with quota
6357                  * files. If this fails, we return success anyway since quotas
6358                  * are already enabled and this is not a hard failure.
6359                  */
6360                 inode_lock(inode);
6361                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6362                 if (IS_ERR(handle))
6363                         goto unlock_inode;
6364                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6365                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6366                                 S_NOATIME | S_IMMUTABLE);
6367                 err = ext4_mark_inode_dirty(handle, inode);
6368                 ext4_journal_stop(handle);
6369         unlock_inode:
6370                 inode_unlock(inode);
6371         }
6372         return err;
6373 }
6374
6375 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6376                              unsigned int flags)
6377 {
6378         int err;
6379         struct inode *qf_inode;
6380         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6381                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6382                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6383                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6384         };
6385
6386         BUG_ON(!ext4_has_feature_quota(sb));
6387
6388         if (!qf_inums[type])
6389                 return -EPERM;
6390
6391         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6392         if (IS_ERR(qf_inode)) {
6393                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6394                 return PTR_ERR(qf_inode);
6395         }
6396
6397         /* Don't account quota for quota files to avoid recursion */
6398         qf_inode->i_flags |= S_NOQUOTA;
6399         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6400         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6401         if (err)
6402                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6403         iput(qf_inode);
6404
6405         return err;
6406 }
6407
6408 /* Enable usage tracking for all quota types. */
6409 static int ext4_enable_quotas(struct super_block *sb)
6410 {
6411         int type, err = 0;
6412         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6413                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6414                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6415                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6416         };
6417         bool quota_mopt[EXT4_MAXQUOTAS] = {
6418                 test_opt(sb, USRQUOTA),
6419                 test_opt(sb, GRPQUOTA),
6420                 test_opt(sb, PRJQUOTA),
6421         };
6422
6423         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6424         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6425                 if (qf_inums[type]) {
6426                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6427                                 DQUOT_USAGE_ENABLED |
6428                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6429                         if (err) {
6430                                 ext4_warning(sb,
6431                                         "Failed to enable quota tracking "
6432                                         "(type=%d, err=%d). Please run "
6433                                         "e2fsck to fix.", type, err);
6434                                 for (type--; type >= 0; type--)
6435                                         dquot_quota_off(sb, type);
6436
6437                                 return err;
6438                         }
6439                 }
6440         }
6441         return 0;
6442 }
6443
6444 static int ext4_quota_off(struct super_block *sb, int type)
6445 {
6446         struct inode *inode = sb_dqopt(sb)->files[type];
6447         handle_t *handle;
6448         int err;
6449
6450         /* Force all delayed allocation blocks to be allocated.
6451          * Caller already holds s_umount sem */
6452         if (test_opt(sb, DELALLOC))
6453                 sync_filesystem(sb);
6454
6455         if (!inode || !igrab(inode))
6456                 goto out;
6457
6458         err = dquot_quota_off(sb, type);
6459         if (err || ext4_has_feature_quota(sb))
6460                 goto out_put;
6461
6462         inode_lock(inode);
6463         /*
6464          * Update modification times of quota files when userspace can
6465          * start looking at them. If we fail, we return success anyway since
6466          * this is not a hard failure and quotas are already disabled.
6467          */
6468         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6469         if (IS_ERR(handle)) {
6470                 err = PTR_ERR(handle);
6471                 goto out_unlock;
6472         }
6473         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6474         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6475         inode->i_mtime = inode->i_ctime = current_time(inode);
6476         err = ext4_mark_inode_dirty(handle, inode);
6477         ext4_journal_stop(handle);
6478 out_unlock:
6479         inode_unlock(inode);
6480 out_put:
6481         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6482         iput(inode);
6483         return err;
6484 out:
6485         return dquot_quota_off(sb, type);
6486 }
6487
6488 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6489  * acquiring the locks... As quota files are never truncated and quota code
6490  * itself serializes the operations (and no one else should touch the files)
6491  * we don't have to be afraid of races */
6492 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6493                                size_t len, loff_t off)
6494 {
6495         struct inode *inode = sb_dqopt(sb)->files[type];
6496         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6497         int offset = off & (sb->s_blocksize - 1);
6498         int tocopy;
6499         size_t toread;
6500         struct buffer_head *bh;
6501         loff_t i_size = i_size_read(inode);
6502
6503         if (off > i_size)
6504                 return 0;
6505         if (off+len > i_size)
6506                 len = i_size-off;
6507         toread = len;
6508         while (toread > 0) {
6509                 tocopy = sb->s_blocksize - offset < toread ?
6510                                 sb->s_blocksize - offset : toread;
6511                 bh = ext4_bread(NULL, inode, blk, 0);
6512                 if (IS_ERR(bh))
6513                         return PTR_ERR(bh);
6514                 if (!bh)        /* A hole? */
6515                         memset(data, 0, tocopy);
6516                 else
6517                         memcpy(data, bh->b_data+offset, tocopy);
6518                 brelse(bh);
6519                 offset = 0;
6520                 toread -= tocopy;
6521                 data += tocopy;
6522                 blk++;
6523         }
6524         return len;
6525 }
6526
6527 /* Write to quotafile (we know the transaction is already started and has
6528  * enough credits) */
6529 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6530                                 const char *data, size_t len, loff_t off)
6531 {
6532         struct inode *inode = sb_dqopt(sb)->files[type];
6533         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6534         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6535         int retries = 0;
6536         struct buffer_head *bh;
6537         handle_t *handle = journal_current_handle();
6538
6539         if (EXT4_SB(sb)->s_journal && !handle) {
6540                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6541                         " cancelled because transaction is not started",
6542                         (unsigned long long)off, (unsigned long long)len);
6543                 return -EIO;
6544         }
6545         /*
6546          * Since we account only one data block in transaction credits,
6547          * then it is impossible to cross a block boundary.
6548          */
6549         if (sb->s_blocksize - offset < len) {
6550                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6551                         " cancelled because not block aligned",
6552                         (unsigned long long)off, (unsigned long long)len);
6553                 return -EIO;
6554         }
6555
6556         do {
6557                 bh = ext4_bread(handle, inode, blk,
6558                                 EXT4_GET_BLOCKS_CREATE |
6559                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6560         } while (PTR_ERR(bh) == -ENOSPC &&
6561                  ext4_should_retry_alloc(inode->i_sb, &retries));
6562         if (IS_ERR(bh))
6563                 return PTR_ERR(bh);
6564         if (!bh)
6565                 goto out;
6566         BUFFER_TRACE(bh, "get write access");
6567         err = ext4_journal_get_write_access(handle, bh);
6568         if (err) {
6569                 brelse(bh);
6570                 return err;
6571         }
6572         lock_buffer(bh);
6573         memcpy(bh->b_data+offset, data, len);
6574         flush_dcache_page(bh->b_page);
6575         unlock_buffer(bh);
6576         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6577         brelse(bh);
6578 out:
6579         if (inode->i_size < off + len) {
6580                 i_size_write(inode, off + len);
6581                 EXT4_I(inode)->i_disksize = inode->i_size;
6582                 err2 = ext4_mark_inode_dirty(handle, inode);
6583                 if (unlikely(err2 && !err))
6584                         err = err2;
6585         }
6586         return err ? err : len;
6587 }
6588 #endif
6589
6590 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6591                        const char *dev_name, void *data)
6592 {
6593         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6594 }
6595
6596 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6597 static inline void register_as_ext2(void)
6598 {
6599         int err = register_filesystem(&ext2_fs_type);
6600         if (err)
6601                 printk(KERN_WARNING
6602                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6603 }
6604
6605 static inline void unregister_as_ext2(void)
6606 {
6607         unregister_filesystem(&ext2_fs_type);
6608 }
6609
6610 static inline int ext2_feature_set_ok(struct super_block *sb)
6611 {
6612         if (ext4_has_unknown_ext2_incompat_features(sb))
6613                 return 0;
6614         if (sb_rdonly(sb))
6615                 return 1;
6616         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6617                 return 0;
6618         return 1;
6619 }
6620 #else
6621 static inline void register_as_ext2(void) { }
6622 static inline void unregister_as_ext2(void) { }
6623 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6624 #endif
6625
6626 static inline void register_as_ext3(void)
6627 {
6628         int err = register_filesystem(&ext3_fs_type);
6629         if (err)
6630                 printk(KERN_WARNING
6631                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6632 }
6633
6634 static inline void unregister_as_ext3(void)
6635 {
6636         unregister_filesystem(&ext3_fs_type);
6637 }
6638
6639 static inline int ext3_feature_set_ok(struct super_block *sb)
6640 {
6641         if (ext4_has_unknown_ext3_incompat_features(sb))
6642                 return 0;
6643         if (!ext4_has_feature_journal(sb))
6644                 return 0;
6645         if (sb_rdonly(sb))
6646                 return 1;
6647         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6648                 return 0;
6649         return 1;
6650 }
6651
6652 static struct file_system_type ext4_fs_type = {
6653         .owner          = THIS_MODULE,
6654         .name           = "ext4",
6655         .mount          = ext4_mount,
6656         .kill_sb        = kill_block_super,
6657         .fs_flags       = FS_REQUIRES_DEV,
6658 };
6659 MODULE_ALIAS_FS("ext4");
6660
6661 /* Shared across all ext4 file systems */
6662 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6663
6664 static int __init ext4_init_fs(void)
6665 {
6666         int i, err;
6667
6668         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6669         ext4_li_info = NULL;
6670         mutex_init(&ext4_li_mtx);
6671
6672         /* Build-time check for flags consistency */
6673         ext4_check_flag_values();
6674
6675         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6676                 init_waitqueue_head(&ext4__ioend_wq[i]);
6677
6678         err = ext4_init_es();
6679         if (err)
6680                 return err;
6681
6682         err = ext4_init_pending();
6683         if (err)
6684                 goto out7;
6685
6686         err = ext4_init_post_read_processing();
6687         if (err)
6688                 goto out6;
6689
6690         err = ext4_init_pageio();
6691         if (err)
6692                 goto out5;
6693
6694         err = ext4_init_system_zone();
6695         if (err)
6696                 goto out4;
6697
6698         err = ext4_init_sysfs();
6699         if (err)
6700                 goto out3;
6701
6702         err = ext4_init_mballoc();
6703         if (err)
6704                 goto out2;
6705         err = init_inodecache();
6706         if (err)
6707                 goto out1;
6708
6709         err = ext4_fc_init_dentry_cache();
6710         if (err)
6711                 goto out05;
6712
6713         register_as_ext3();
6714         register_as_ext2();
6715         err = register_filesystem(&ext4_fs_type);
6716         if (err)
6717                 goto out;
6718
6719         return 0;
6720 out:
6721         unregister_as_ext2();
6722         unregister_as_ext3();
6723 out05:
6724         destroy_inodecache();
6725 out1:
6726         ext4_exit_mballoc();
6727 out2:
6728         ext4_exit_sysfs();
6729 out3:
6730         ext4_exit_system_zone();
6731 out4:
6732         ext4_exit_pageio();
6733 out5:
6734         ext4_exit_post_read_processing();
6735 out6:
6736         ext4_exit_pending();
6737 out7:
6738         ext4_exit_es();
6739
6740         return err;
6741 }
6742
6743 static void __exit ext4_exit_fs(void)
6744 {
6745         ext4_destroy_lazyinit_thread();
6746         unregister_as_ext2();
6747         unregister_as_ext3();
6748         unregister_filesystem(&ext4_fs_type);
6749         destroy_inodecache();
6750         ext4_exit_mballoc();
6751         ext4_exit_sysfs();
6752         ext4_exit_system_zone();
6753         ext4_exit_pageio();
6754         ext4_exit_post_read_processing();
6755         ext4_exit_es();
6756         ext4_exit_pending();
6757 }
6758
6759 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6760 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6761 MODULE_LICENSE("GPL");
6762 MODULE_SOFTDEP("pre: crc32c");
6763 module_init(ext4_init_fs)
6764 module_exit(ext4_exit_fs)