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 ([email protected])
   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 ([email protected]), 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 DEFINE_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         /*
 671          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 672          * could panic during 'reboot -f' as the underlying device got already
 673          * disabled.
 674          */
 675         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
 676                 panic("EXT4-fs (device %s): panic forced after error\n",
 677                         sb->s_id);
 678         }
 679
 680         if (sb_rdonly(sb) || continue_fs)
 681                 return;
 682
 683         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 684         /*
 685          * Make sure updated value of ->s_mount_flags will be visible before
 686          * ->s_flags update
 687          */
 688         smp_wmb();
 689         sb->s_flags |= SB_RDONLY;
 690 }
 691
 692 static void flush_stashed_error_work(struct work_struct *work)
 693 {
 694         struct ext4_sb_info *sbi = container_of(work, struct ext4_sb_info,
 695                                                 s_error_work);
 696         journal_t *journal = sbi->s_journal;
 697         handle_t *handle;
 698
 699         /*
 700          * If the journal is still running, we have to write out superblock
 701          * through the journal to avoid collisions of other journalled sb
 702          * updates.
 703          *
 704          * We use directly jbd2 functions here to avoid recursing back into
 705          * ext4 error handling code during handling of previous errors.
 706          */
 707         if (!sb_rdonly(sbi->s_sb) && journal) {
 708                 handle = jbd2_journal_start(journal, 1);
 709                 if (IS_ERR(handle))
 710                         goto write_directly;
 711                 if (jbd2_journal_get_write_access(handle, sbi->s_sbh)) {
 712                         jbd2_journal_stop(handle);
 713                         goto write_directly;
 714                 }
 715                 ext4_update_super(sbi->s_sb);
 716                 if (jbd2_journal_dirty_metadata(handle, sbi->s_sbh)) {
 717                         jbd2_journal_stop(handle);
 718                         goto write_directly;
 719                 }
 720                 jbd2_journal_stop(handle);
 721                 return;
 722         }
 723 write_directly:
 724         /*
 725          * Write through journal failed. Write sb directly to get error info
 726          * out and hope for the best.
 727          */
 728         ext4_commit_super(sbi->s_sb);
 729 }
 730
 731 #define ext4_error_ratelimit(sb)                                        \
 732                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 733                              "EXT4-fs error")
 734
 735 void __ext4_error(struct super_block *sb, const char *function,
 736                   unsigned int line, bool force_ro, int error, __u64 block,
 737                   const char *fmt, ...)
 738 {
 739         struct va_format vaf;
 740         va_list args;
 741
 742         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 743                 return;
 744
 745         trace_ext4_error(sb, function, line);
 746         if (ext4_error_ratelimit(sb)) {
 747                 va_start(args, fmt);
 748                 vaf.fmt = fmt;
 749                 vaf.va = &args;
 750                 printk(KERN_CRIT
 751                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 752                        sb->s_id, function, line, current->comm, &vaf);
 753                 va_end(args);
 754         }
 755         ext4_handle_error(sb, force_ro, error, 0, block, function, line);
 756 }
 757
 758 void __ext4_error_inode(struct inode *inode, const char *function,
 759                         unsigned int line, ext4_fsblk_t block, int error,
 760                         const char *fmt, ...)
 761 {
 762         va_list args;
 763         struct va_format vaf;
 764
 765         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 766                 return;
 767
 768         trace_ext4_error(inode->i_sb, function, line);
 769         if (ext4_error_ratelimit(inode->i_sb)) {
 770                 va_start(args, fmt);
 771                 vaf.fmt = fmt;
 772                 vaf.va = &args;
 773                 if (block)
 774                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 775                                "inode #%lu: block %llu: comm %s: %pV\n",
 776                                inode->i_sb->s_id, function, line, inode->i_ino,
 777                                block, current->comm, &vaf);
 778                 else
 779                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 780                                "inode #%lu: comm %s: %pV\n",
 781                                inode->i_sb->s_id, function, line, inode->i_ino,
 782                                current->comm, &vaf);
 783                 va_end(args);
 784         }
 785         ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
 786                           function, line);
 787 }
 788
 789 void __ext4_error_file(struct file *file, const char *function,
 790                        unsigned int line, ext4_fsblk_t block,
 791                        const char *fmt, ...)
 792 {
 793         va_list args;
 794         struct va_format vaf;
 795         struct inode *inode = file_inode(file);
 796         char pathname[80], *path;
 797
 798         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 799                 return;
 800
 801         trace_ext4_error(inode->i_sb, function, line);
 802         if (ext4_error_ratelimit(inode->i_sb)) {
 803                 path = file_path(file, pathname, sizeof(pathname));
 804                 if (IS_ERR(path))
 805                         path = "(unknown)";
 806                 va_start(args, fmt);
 807                 vaf.fmt = fmt;
 808                 vaf.va = &args;
 809                 if (block)
 810                         printk(KERN_CRIT
 811                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 812                                "block %llu: comm %s: path %s: %pV\n",
 813                                inode->i_sb->s_id, function, line, inode->i_ino,
 814                                block, current->comm, path, &vaf);
 815                 else
 816                         printk(KERN_CRIT
 817                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 818                                "comm %s: path %s: %pV\n",
 819                                inode->i_sb->s_id, function, line, inode->i_ino,
 820                                current->comm, path, &vaf);
 821                 va_end(args);
 822         }
 823         ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
 824                           function, line);
 825 }
 826
 827 const char *ext4_decode_error(struct super_block *sb, int errno,
 828                               char nbuf[16])
 829 {
 830         char *errstr = NULL;
 831
 832         switch (errno) {
 833         case -EFSCORRUPTED:
 834                 errstr = "Corrupt filesystem";
 835                 break;
 836         case -EFSBADCRC:
 837                 errstr = "Filesystem failed CRC";
 838                 break;
 839         case -EIO:
 840                 errstr = "IO failure";
 841                 break;
 842         case -ENOMEM:
 843                 errstr = "Out of memory";
 844                 break;
 845         case -EROFS:
 846                 if (!sb || (EXT4_SB(sb)->s_journal &&
 847                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 848                         errstr = "Journal has aborted";
 849                 else
 850                         errstr = "Readonly filesystem";
 851                 break;
 852         default:
 853                 /* If the caller passed in an extra buffer for unknown
 854                  * errors, textualise them now.  Else we just return
 855                  * NULL. */
 856                 if (nbuf) {
 857                         /* Check for truncated error codes... */
 858                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 859                                 errstr = nbuf;
 860                 }
 861                 break;
 862         }
 863
 864         return errstr;
 865 }
 866
 867 /* __ext4_std_error decodes expected errors from journaling functions
 868  * automatically and invokes the appropriate error response.  */
 869
 870 void __ext4_std_error(struct super_block *sb, const char *function,
 871                       unsigned int line, int errno)
 872 {
 873         char nbuf[16];
 874         const char *errstr;
 875
 876         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 877                 return;
 878
 879         /* Special case: if the error is EROFS, and we're not already
 880          * inside a transaction, then there's really no point in logging
 881          * an error. */
 882         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 883                 return;
 884
 885         if (ext4_error_ratelimit(sb)) {
 886                 errstr = ext4_decode_error(sb, errno, nbuf);
 887                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 888                        sb->s_id, function, line, errstr);
 889         }
 890
 891         ext4_handle_error(sb, false, -errno, 0, 0, function, line);
 892 }
 893
 894 void __ext4_msg(struct super_block *sb,
 895                 const char *prefix, const char *fmt, ...)
 896 {
 897         struct va_format vaf;
 898         va_list args;
 899
 900         atomic_inc(&EXT4_SB(sb)->s_msg_count);
 901         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 902                 return;
 903
 904         va_start(args, fmt);
 905         vaf.fmt = fmt;
 906         vaf.va = &args;
 907         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 908         va_end(args);
 909 }
 910
 911 static int ext4_warning_ratelimit(struct super_block *sb)
 912 {
 913         atomic_inc(&EXT4_SB(sb)->s_warning_count);
 914         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
 915                             "EXT4-fs warning");
 916 }
 917
 918 void __ext4_warning(struct super_block *sb, const char *function,
 919                     unsigned int line, const char *fmt, ...)
 920 {
 921         struct va_format vaf;
 922         va_list args;
 923
 924         if (!ext4_warning_ratelimit(sb))
 925                 return;
 926
 927         va_start(args, fmt);
 928         vaf.fmt = fmt;
 929         vaf.va = &args;
 930         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 931                sb->s_id, function, line, &vaf);
 932         va_end(args);
 933 }
 934
 935 void __ext4_warning_inode(const struct inode *inode, const char *function,
 936                           unsigned int line, const char *fmt, ...)
 937 {
 938         struct va_format vaf;
 939         va_list args;
 940
 941         if (!ext4_warning_ratelimit(inode->i_sb))
 942                 return;
 943
 944         va_start(args, fmt);
 945         vaf.fmt = fmt;
 946         vaf.va = &args;
 947         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 948                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 949                function, line, inode->i_ino, current->comm, &vaf);
 950         va_end(args);
 951 }
 952
 953 void __ext4_grp_locked_error(const char *function, unsigned int line,
 954                              struct super_block *sb, ext4_group_t grp,
 955                              unsigned long ino, ext4_fsblk_t block,
 956                              const char *fmt, ...)
 957 __releases(bitlock)
 958 __acquires(bitlock)
 959 {
 960         struct va_format vaf;
 961         va_list args;
 962
 963         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 964                 return;
 965
 966         trace_ext4_error(sb, function, line);
 967         if (ext4_error_ratelimit(sb)) {
 968                 va_start(args, fmt);
 969                 vaf.fmt = fmt;
 970                 vaf.va = &args;
 971                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 972                        sb->s_id, function, line, grp);
 973                 if (ino)
 974                         printk(KERN_CONT "inode %lu: ", ino);
 975                 if (block)
 976                         printk(KERN_CONT "block %llu:",
 977                                (unsigned long long) block);
 978                 printk(KERN_CONT "%pV\n", &vaf);
 979                 va_end(args);
 980         }
 981
 982         if (test_opt(sb, ERRORS_CONT)) {
 983                 if (test_opt(sb, WARN_ON_ERROR))
 984                         WARN_ON_ONCE(1);
 985                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 986                 if (!bdev_read_only(sb->s_bdev)) {
 987                         save_error_info(sb, EFSCORRUPTED, ino, block, function,
 988                                         line);
 989                         schedule_work(&EXT4_SB(sb)->s_error_work);
 990                 }
 991                 return;
 992         }
 993         ext4_unlock_group(sb, grp);
 994         ext4_handle_error(sb, false, EFSCORRUPTED, ino, block, function, line);
 995         /*
 996          * We only get here in the ERRORS_RO case; relocking the group
 997          * may be dangerous, but nothing bad will happen since the
 998          * filesystem will have already been marked read/only and the
 999          * journal has been aborted.  We return 1 as a hint to callers
1000          * who might what to use the return value from
1001          * ext4_grp_locked_error() to distinguish between the
1002          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1003          * aggressively from the ext4 function in question, with a
1004          * more appropriate error code.
1005          */
1006         ext4_lock_group(sb, grp);
1007         return;
1008 }
1009
1010 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1011                                      ext4_group_t group,
1012                                      unsigned int flags)
1013 {
1014         struct ext4_sb_info *sbi = EXT4_SB(sb);
1015         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1016         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1017         int ret;
1018
1019         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1020                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1021                                             &grp->bb_state);
1022                 if (!ret)
1023                         percpu_counter_sub(&sbi->s_freeclusters_counter,
1024                                            grp->bb_free);
1025         }
1026
1027         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1028                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1029                                             &grp->bb_state);
1030                 if (!ret && gdp) {
1031                         int count;
1032
1033                         count = ext4_free_inodes_count(sb, gdp);
1034                         percpu_counter_sub(&sbi->s_freeinodes_counter,
1035                                            count);
1036                 }
1037         }
1038 }
1039
1040 void ext4_update_dynamic_rev(struct super_block *sb)
1041 {
1042         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1043
1044         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1045                 return;
1046
1047         ext4_warning(sb,
1048                      "updating to rev %d because of new feature flag, "
1049                      "running e2fsck is recommended",
1050                      EXT4_DYNAMIC_REV);
1051
1052         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1053         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1054         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1055         /* leave es->s_feature_*compat flags alone */
1056         /* es->s_uuid will be set by e2fsck if empty */
1057
1058         /*
1059          * The rest of the superblock fields should be zero, and if not it
1060          * means they are likely already in use, so leave them alone.  We
1061          * can leave it up to e2fsck to clean up any inconsistencies there.
1062          */
1063 }
1064
1065 /*
1066  * Open the external journal device
1067  */
1068 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
1069 {
1070         struct block_device *bdev;
1071
1072         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
1073         if (IS_ERR(bdev))
1074                 goto fail;
1075         return bdev;
1076
1077 fail:
1078         ext4_msg(sb, KERN_ERR,
1079                  "failed to open journal device unknown-block(%u,%u) %ld",
1080                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
1081         return NULL;
1082 }
1083
1084 /*
1085  * Release the journal device
1086  */
1087 static void ext4_blkdev_put(struct block_device *bdev)
1088 {
1089         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1090 }
1091
1092 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
1093 {
1094         struct block_device *bdev;
1095         bdev = sbi->s_journal_bdev;
1096         if (bdev) {
1097                 ext4_blkdev_put(bdev);
1098                 sbi->s_journal_bdev = NULL;
1099         }
1100 }
1101
1102 static inline struct inode *orphan_list_entry(struct list_head *l)
1103 {
1104         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1105 }
1106
1107 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1108 {
1109         struct list_head *l;
1110
1111         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1112                  le32_to_cpu(sbi->s_es->s_last_orphan));
1113
1114         printk(KERN_ERR "sb_info orphan list:\n");
1115         list_for_each(l, &sbi->s_orphan) {
1116                 struct inode *inode = orphan_list_entry(l);
1117                 printk(KERN_ERR "  "
1118                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1119                        inode->i_sb->s_id, inode->i_ino, inode,
1120                        inode->i_mode, inode->i_nlink,
1121                        NEXT_ORPHAN(inode));
1122         }
1123 }
1124
1125 #ifdef CONFIG_QUOTA
1126 static int ext4_quota_off(struct super_block *sb, int type);
1127
1128 static inline void ext4_quota_off_umount(struct super_block *sb)
1129 {
1130         int type;
1131
1132         /* Use our quota_off function to clear inode flags etc. */
1133         for (type = 0; type < EXT4_MAXQUOTAS; type++)
1134                 ext4_quota_off(sb, type);
1135 }
1136
1137 /*
1138  * This is a helper function which is used in the mount/remount
1139  * codepaths (which holds s_umount) to fetch the quota file name.
1140  */
1141 static inline char *get_qf_name(struct super_block *sb,
1142                                 struct ext4_sb_info *sbi,
1143                                 int type)
1144 {
1145         return rcu_dereference_protected(sbi->s_qf_names[type],
1146                                          lockdep_is_held(&sb->s_umount));
1147 }
1148 #else
1149 static inline void ext4_quota_off_umount(struct super_block *sb)
1150 {
1151 }
1152 #endif
1153
1154 static void ext4_put_super(struct super_block *sb)
1155 {
1156         struct ext4_sb_info *sbi = EXT4_SB(sb);
1157         struct ext4_super_block *es = sbi->s_es;
1158         struct buffer_head **group_desc;
1159         struct flex_groups **flex_groups;
1160         int aborted = 0;
1161         int i, err;
1162
1163         ext4_unregister_li_request(sb);
1164         ext4_quota_off_umount(sb);
1165
1166         flush_work(&sbi->s_error_work);
1167         destroy_workqueue(sbi->rsv_conversion_wq);
1168
1169         /*
1170          * Unregister sysfs before destroying jbd2 journal.
1171          * Since we could still access attr_journal_task attribute via sysfs
1172          * path which could have sbi->s_journal->j_task as NULL
1173          */
1174         ext4_unregister_sysfs(sb);
1175
1176         if (sbi->s_journal) {
1177                 aborted = is_journal_aborted(sbi->s_journal);
1178                 err = jbd2_journal_destroy(sbi->s_journal);
1179                 sbi->s_journal = NULL;
1180                 if ((err < 0) && !aborted) {
1181                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1182                 }
1183         }
1184
1185         ext4_es_unregister_shrinker(sbi);
1186         del_timer_sync(&sbi->s_err_report);
1187         ext4_release_system_zone(sb);
1188         ext4_mb_release(sb);
1189         ext4_ext_release(sb);
1190
1191         if (!sb_rdonly(sb) && !aborted) {
1192                 ext4_clear_feature_journal_needs_recovery(sb);
1193                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1194         }
1195         if (!sb_rdonly(sb))
1196                 ext4_commit_super(sb);
1197
1198         rcu_read_lock();
1199         group_desc = rcu_dereference(sbi->s_group_desc);
1200         for (i = 0; i < sbi->s_gdb_count; i++)
1201                 brelse(group_desc[i]);
1202         kvfree(group_desc);
1203         flex_groups = rcu_dereference(sbi->s_flex_groups);
1204         if (flex_groups) {
1205                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1206                         kvfree(flex_groups[i]);
1207                 kvfree(flex_groups);
1208         }
1209         rcu_read_unlock();
1210         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1211         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1212         percpu_counter_destroy(&sbi->s_dirs_counter);
1213         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1214         percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
1215         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1216 #ifdef CONFIG_QUOTA
1217         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1218                 kfree(get_qf_name(sb, sbi, i));
1219 #endif
1220
1221         /* Debugging code just in case the in-memory inode orphan list
1222          * isn't empty.  The on-disk one can be non-empty if we've
1223          * detected an error and taken the fs readonly, but the
1224          * in-memory list had better be clean by this point. */
1225         if (!list_empty(&sbi->s_orphan))
1226                 dump_orphan_list(sb, sbi);
1227         ASSERT(list_empty(&sbi->s_orphan));
1228
1229         sync_blockdev(sb->s_bdev);
1230         invalidate_bdev(sb->s_bdev);
1231         if (sbi->s_journal_bdev && sbi->s_journal_bdev != sb->s_bdev) {
1232                 /*
1233                  * Invalidate the journal device's buffers.  We don't want them
1234                  * floating about in memory - the physical journal device may
1235                  * hotswapped, and it breaks the `ro-after' testing code.
1236                  */
1237                 sync_blockdev(sbi->s_journal_bdev);
1238                 invalidate_bdev(sbi->s_journal_bdev);
1239                 ext4_blkdev_remove(sbi);
1240         }
1241
1242         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1243         sbi->s_ea_inode_cache = NULL;
1244
1245         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1246         sbi->s_ea_block_cache = NULL;
1247
1248         ext4_stop_mmpd(sbi);
1249
1250         brelse(sbi->s_sbh);
1251         sb->s_fs_info = NULL;
1252         /*
1253          * Now that we are completely done shutting down the
1254          * superblock, we need to actually destroy the kobject.
1255          */
1256         kobject_put(&sbi->s_kobj);
1257         wait_for_completion(&sbi->s_kobj_unregister);
1258         if (sbi->s_chksum_driver)
1259                 crypto_free_shash(sbi->s_chksum_driver);
1260         kfree(sbi->s_blockgroup_lock);
1261         fs_put_dax(sbi->s_daxdev);
1262         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1263 #ifdef CONFIG_UNICODE
1264         utf8_unload(sb->s_encoding);
1265 #endif
1266         kfree(sbi);
1267 }
1268
1269 static struct kmem_cache *ext4_inode_cachep;
1270
1271 /*
1272  * Called inside transaction, so use GFP_NOFS
1273  */
1274 static struct inode *ext4_alloc_inode(struct super_block *sb)
1275 {
1276         struct ext4_inode_info *ei;
1277
1278         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1279         if (!ei)
1280                 return NULL;
1281
1282         inode_set_iversion(&ei->vfs_inode, 1);
1283         spin_lock_init(&ei->i_raw_lock);
1284         INIT_LIST_HEAD(&ei->i_prealloc_list);
1285         atomic_set(&ei->i_prealloc_active, 0);
1286         spin_lock_init(&ei->i_prealloc_lock);
1287         ext4_es_init_tree(&ei->i_es_tree);
1288         rwlock_init(&ei->i_es_lock);
1289         INIT_LIST_HEAD(&ei->i_es_list);
1290         ei->i_es_all_nr = 0;
1291         ei->i_es_shk_nr = 0;
1292         ei->i_es_shrink_lblk = 0;
1293         ei->i_reserved_data_blocks = 0;
1294         spin_lock_init(&(ei->i_block_reservation_lock));
1295         ext4_init_pending_tree(&ei->i_pending_tree);
1296 #ifdef CONFIG_QUOTA
1297         ei->i_reserved_quota = 0;
1298         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1299 #endif
1300         ei->jinode = NULL;
1301         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1302         spin_lock_init(&ei->i_completed_io_lock);
1303         ei->i_sync_tid = 0;
1304         ei->i_datasync_tid = 0;
1305         atomic_set(&ei->i_unwritten, 0);
1306         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1307         ext4_fc_init_inode(&ei->vfs_inode);
1308         mutex_init(&ei->i_fc_lock);
1309         return &ei->vfs_inode;
1310 }
1311
1312 static int ext4_drop_inode(struct inode *inode)
1313 {
1314         int drop = generic_drop_inode(inode);
1315
1316         if (!drop)
1317                 drop = fscrypt_drop_inode(inode);
1318
1319         trace_ext4_drop_inode(inode, drop);
1320         return drop;
1321 }
1322
1323 static void ext4_free_in_core_inode(struct inode *inode)
1324 {
1325         fscrypt_free_inode(inode);
1326         if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1327                 pr_warn("%s: inode %ld still in fc list",
1328                         __func__, inode->i_ino);
1329         }
1330         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1331 }
1332
1333 static void ext4_destroy_inode(struct inode *inode)
1334 {
1335         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1336                 ext4_msg(inode->i_sb, KERN_ERR,
1337                          "Inode %lu (%p): orphan list check failed!",
1338                          inode->i_ino, EXT4_I(inode));
1339                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1340                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1341                                 true);
1342                 dump_stack();
1343         }
1344 }
1345
1346 static void init_once(void *foo)
1347 {
1348         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1349
1350         INIT_LIST_HEAD(&ei->i_orphan);
1351         init_rwsem(&ei->xattr_sem);
1352         init_rwsem(&ei->i_data_sem);
1353         init_rwsem(&ei->i_mmap_sem);
1354         inode_init_once(&ei->vfs_inode);
1355         ext4_fc_init_inode(&ei->vfs_inode);
1356 }
1357
1358 static int __init init_inodecache(void)
1359 {
1360         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1361                                 sizeof(struct ext4_inode_info), 0,
1362                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1363                                         SLAB_ACCOUNT),
1364                                 offsetof(struct ext4_inode_info, i_data),
1365                                 sizeof_field(struct ext4_inode_info, i_data),
1366                                 init_once);
1367         if (ext4_inode_cachep == NULL)
1368                 return -ENOMEM;
1369         return 0;
1370 }
1371
1372 static void destroy_inodecache(void)
1373 {
1374         /*
1375          * Make sure all delayed rcu free inodes are flushed before we
1376          * destroy cache.
1377          */
1378         rcu_barrier();
1379         kmem_cache_destroy(ext4_inode_cachep);
1380 }
1381
1382 void ext4_clear_inode(struct inode *inode)
1383 {
1384         ext4_fc_del(inode);
1385         invalidate_inode_buffers(inode);
1386         clear_inode(inode);
1387         ext4_discard_preallocations(inode, 0);
1388         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1389         dquot_drop(inode);
1390         if (EXT4_I(inode)->jinode) {
1391                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1392                                                EXT4_I(inode)->jinode);
1393                 jbd2_free_inode(EXT4_I(inode)->jinode);
1394                 EXT4_I(inode)->jinode = NULL;
1395         }
1396         fscrypt_put_encryption_info(inode);
1397         fsverity_cleanup_inode(inode);
1398 }
1399
1400 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1401                                         u64 ino, u32 generation)
1402 {
1403         struct inode *inode;
1404
1405         /*
1406          * Currently we don't know the generation for parent directory, so
1407          * a generation of 0 means "accept any"
1408          */
1409         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1410         if (IS_ERR(inode))
1411                 return ERR_CAST(inode);
1412         if (generation && inode->i_generation != generation) {
1413                 iput(inode);
1414                 return ERR_PTR(-ESTALE);
1415         }
1416
1417         return inode;
1418 }
1419
1420 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1421                                         int fh_len, int fh_type)
1422 {
1423         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1424                                     ext4_nfs_get_inode);
1425 }
1426
1427 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1428                                         int fh_len, int fh_type)
1429 {
1430         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1431                                     ext4_nfs_get_inode);
1432 }
1433
1434 static int ext4_nfs_commit_metadata(struct inode *inode)
1435 {
1436         struct writeback_control wbc = {
1437                 .sync_mode = WB_SYNC_ALL
1438         };
1439
1440         trace_ext4_nfs_commit_metadata(inode);
1441         return ext4_write_inode(inode, &wbc);
1442 }
1443
1444 /*
1445  * Try to release metadata pages (indirect blocks, directories) which are
1446  * mapped via the block device.  Since these pages could have journal heads
1447  * which would prevent try_to_free_buffers() from freeing them, we must use
1448  * jbd2 layer's try_to_free_buffers() function to release them.
1449  */
1450 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1451                                  gfp_t wait)
1452 {
1453         journal_t *journal = EXT4_SB(sb)->s_journal;
1454
1455         WARN_ON(PageChecked(page));
1456         if (!page_has_buffers(page))
1457                 return 0;
1458         if (journal)
1459                 return jbd2_journal_try_to_free_buffers(journal, page);
1460
1461         return try_to_free_buffers(page);
1462 }
1463
1464 #ifdef CONFIG_FS_ENCRYPTION
1465 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1466 {
1467         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1468                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1469 }
1470
1471 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1472                                                         void *fs_data)
1473 {
1474         handle_t *handle = fs_data;
1475         int res, res2, credits, retries = 0;
1476
1477         /*
1478          * Encrypting the root directory is not allowed because e2fsck expects
1479          * lost+found to exist and be unencrypted, and encrypting the root
1480          * directory would imply encrypting the lost+found directory as well as
1481          * the filename "lost+found" itself.
1482          */
1483         if (inode->i_ino == EXT4_ROOT_INO)
1484                 return -EPERM;
1485
1486         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1487                 return -EINVAL;
1488
1489         if (ext4_test_inode_flag(inode, EXT4_INODE_DAX))
1490                 return -EOPNOTSUPP;
1491
1492         res = ext4_convert_inline_data(inode);
1493         if (res)
1494                 return res;
1495
1496         /*
1497          * If a journal handle was specified, then the encryption context is
1498          * being set on a new inode via inheritance and is part of a larger
1499          * transaction to create the inode.  Otherwise the encryption context is
1500          * being set on an existing inode in its own transaction.  Only in the
1501          * latter case should the "retry on ENOSPC" logic be used.
1502          */
1503
1504         if (handle) {
1505                 res = ext4_xattr_set_handle(handle, inode,
1506                                             EXT4_XATTR_INDEX_ENCRYPTION,
1507                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1508                                             ctx, len, 0);
1509                 if (!res) {
1510                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1511                         ext4_clear_inode_state(inode,
1512                                         EXT4_STATE_MAY_INLINE_DATA);
1513                         /*
1514                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1515                          * S_DAX may be disabled
1516                          */
1517                         ext4_set_inode_flags(inode, false);
1518                 }
1519                 return res;
1520         }
1521
1522         res = dquot_initialize(inode);
1523         if (res)
1524                 return res;
1525 retry:
1526         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1527                                      &credits);
1528         if (res)
1529                 return res;
1530
1531         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1532         if (IS_ERR(handle))
1533                 return PTR_ERR(handle);
1534
1535         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1536                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1537                                     ctx, len, 0);
1538         if (!res) {
1539                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1540                 /*
1541                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1542                  * S_DAX may be disabled
1543                  */
1544                 ext4_set_inode_flags(inode, false);
1545                 res = ext4_mark_inode_dirty(handle, inode);
1546                 if (res)
1547                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1548         }
1549         res2 = ext4_journal_stop(handle);
1550
1551         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1552                 goto retry;
1553         if (!res)
1554                 res = res2;
1555         return res;
1556 }
1557
1558 static const union fscrypt_policy *ext4_get_dummy_policy(struct super_block *sb)
1559 {
1560         return EXT4_SB(sb)->s_dummy_enc_policy.policy;
1561 }
1562
1563 static bool ext4_has_stable_inodes(struct super_block *sb)
1564 {
1565         return ext4_has_feature_stable_inodes(sb);
1566 }
1567
1568 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1569                                        int *ino_bits_ret, int *lblk_bits_ret)
1570 {
1571         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1572         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1573 }
1574
1575 static const struct fscrypt_operations ext4_cryptops = {
1576         .key_prefix             = "ext4:",
1577         .get_context            = ext4_get_context,
1578         .set_context            = ext4_set_context,
1579         .get_dummy_policy       = ext4_get_dummy_policy,
1580         .empty_dir              = ext4_empty_dir,
1581         .max_namelen            = EXT4_NAME_LEN,
1582         .has_stable_inodes      = ext4_has_stable_inodes,
1583         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1584 };
1585 #endif
1586
1587 #ifdef CONFIG_QUOTA
1588 static const char * const quotatypes[] = INITQFNAMES;
1589 #define QTYPE2NAME(t) (quotatypes[t])
1590
1591 static int ext4_write_dquot(struct dquot *dquot);
1592 static int ext4_acquire_dquot(struct dquot *dquot);
1593 static int ext4_release_dquot(struct dquot *dquot);
1594 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1595 static int ext4_write_info(struct super_block *sb, int type);
1596 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1597                          const struct path *path);
1598 static int ext4_quota_on_mount(struct super_block *sb, int type);
1599 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1600                                size_t len, loff_t off);
1601 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1602                                 const char *data, size_t len, loff_t off);
1603 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1604                              unsigned int flags);
1605 static int ext4_enable_quotas(struct super_block *sb);
1606
1607 static struct dquot **ext4_get_dquots(struct inode *inode)
1608 {
1609         return EXT4_I(inode)->i_dquot;
1610 }
1611
1612 static const struct dquot_operations ext4_quota_operations = {
1613         .get_reserved_space     = ext4_get_reserved_space,
1614         .write_dquot            = ext4_write_dquot,
1615         .acquire_dquot          = ext4_acquire_dquot,
1616         .release_dquot          = ext4_release_dquot,
1617         .mark_dirty             = ext4_mark_dquot_dirty,
1618         .write_info             = ext4_write_info,
1619         .alloc_dquot            = dquot_alloc,
1620         .destroy_dquot          = dquot_destroy,
1621         .get_projid             = ext4_get_projid,
1622         .get_inode_usage        = ext4_get_inode_usage,
1623         .get_next_id            = dquot_get_next_id,
1624 };
1625
1626 static const struct quotactl_ops ext4_qctl_operations = {
1627         .quota_on       = ext4_quota_on,
1628         .quota_off      = ext4_quota_off,
1629         .quota_sync     = dquot_quota_sync,
1630         .get_state      = dquot_get_state,
1631         .set_info       = dquot_set_dqinfo,
1632         .get_dqblk      = dquot_get_dqblk,
1633         .set_dqblk      = dquot_set_dqblk,
1634         .get_nextdqblk  = dquot_get_next_dqblk,
1635 };
1636 #endif
1637
1638 static const struct super_operations ext4_sops = {
1639         .alloc_inode    = ext4_alloc_inode,
1640         .free_inode     = ext4_free_in_core_inode,
1641         .destroy_inode  = ext4_destroy_inode,
1642         .write_inode    = ext4_write_inode,
1643         .dirty_inode    = ext4_dirty_inode,
1644         .drop_inode     = ext4_drop_inode,
1645         .evict_inode    = ext4_evict_inode,
1646         .put_super      = ext4_put_super,
1647         .sync_fs        = ext4_sync_fs,
1648         .freeze_fs      = ext4_freeze,
1649         .unfreeze_fs    = ext4_unfreeze,
1650         .statfs         = ext4_statfs,
1651         .remount_fs     = ext4_remount,
1652         .show_options   = ext4_show_options,
1653 #ifdef CONFIG_QUOTA
1654         .quota_read     = ext4_quota_read,
1655         .quota_write    = ext4_quota_write,
1656         .get_dquots     = ext4_get_dquots,
1657 #endif
1658         .bdev_try_to_free_page = bdev_try_to_free_page,
1659 };
1660
1661 static const struct export_operations ext4_export_ops = {
1662         .fh_to_dentry = ext4_fh_to_dentry,
1663         .fh_to_parent = ext4_fh_to_parent,
1664         .get_parent = ext4_get_parent,
1665         .commit_metadata = ext4_nfs_commit_metadata,
1666 };
1667
1668 enum {
1669         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1670         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1671         Opt_nouid32, Opt_debug, Opt_removed,
1672         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1673         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1674         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1675         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1676         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1677         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1678         Opt_inlinecrypt,
1679         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1680         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1681         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1682         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
1683         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1684         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1685         Opt_nowarn_on_error, Opt_mblk_io_submit,
1686         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1687         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1688         Opt_inode_readahead_blks, Opt_journal_ioprio,
1689         Opt_dioread_nolock, Opt_dioread_lock,
1690         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1691         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1692         Opt_no_prefetch_block_bitmaps, Opt_mb_optimize_scan,
1693 #ifdef CONFIG_EXT4_DEBUG
1694         Opt_fc_debug_max_replay, Opt_fc_debug_force
1695 #endif
1696 };
1697
1698 static const match_table_t tokens = {
1699         {Opt_bsd_df, "bsddf"},
1700         {Opt_minix_df, "minixdf"},
1701         {Opt_grpid, "grpid"},
1702         {Opt_grpid, "bsdgroups"},
1703         {Opt_nogrpid, "nogrpid"},
1704         {Opt_nogrpid, "sysvgroups"},
1705         {Opt_resgid, "resgid=%u"},
1706         {Opt_resuid, "resuid=%u"},
1707         {Opt_sb, "sb=%u"},
1708         {Opt_err_cont, "errors=continue"},
1709         {Opt_err_panic, "errors=panic"},
1710         {Opt_err_ro, "errors=remount-ro"},
1711         {Opt_nouid32, "nouid32"},
1712         {Opt_debug, "debug"},
1713         {Opt_removed, "oldalloc"},
1714         {Opt_removed, "orlov"},
1715         {Opt_user_xattr, "user_xattr"},
1716         {Opt_nouser_xattr, "nouser_xattr"},
1717         {Opt_acl, "acl"},
1718         {Opt_noacl, "noacl"},
1719         {Opt_noload, "norecovery"},
1720         {Opt_noload, "noload"},
1721         {Opt_removed, "nobh"},
1722         {Opt_removed, "bh"},
1723         {Opt_commit, "commit=%u"},
1724         {Opt_min_batch_time, "min_batch_time=%u"},
1725         {Opt_max_batch_time, "max_batch_time=%u"},
1726         {Opt_journal_dev, "journal_dev=%u"},
1727         {Opt_journal_path, "journal_path=%s"},
1728         {Opt_journal_checksum, "journal_checksum"},
1729         {Opt_nojournal_checksum, "nojournal_checksum"},
1730         {Opt_journal_async_commit, "journal_async_commit"},
1731         {Opt_abort, "abort"},
1732         {Opt_data_journal, "data=journal"},
1733         {Opt_data_ordered, "data=ordered"},
1734         {Opt_data_writeback, "data=writeback"},
1735         {Opt_data_err_abort, "data_err=abort"},
1736         {Opt_data_err_ignore, "data_err=ignore"},
1737         {Opt_offusrjquota, "usrjquota="},
1738         {Opt_usrjquota, "usrjquota=%s"},
1739         {Opt_offgrpjquota, "grpjquota="},
1740         {Opt_grpjquota, "grpjquota=%s"},
1741         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1742         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1743         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1744         {Opt_grpquota, "grpquota"},
1745         {Opt_noquota, "noquota"},
1746         {Opt_quota, "quota"},
1747         {Opt_usrquota, "usrquota"},
1748         {Opt_prjquota, "prjquota"},
1749         {Opt_barrier, "barrier=%u"},
1750         {Opt_barrier, "barrier"},
1751         {Opt_nobarrier, "nobarrier"},
1752         {Opt_i_version, "i_version"},
1753         {Opt_dax, "dax"},
1754         {Opt_dax_always, "dax=always"},
1755         {Opt_dax_inode, "dax=inode"},
1756         {Opt_dax_never, "dax=never"},
1757         {Opt_stripe, "stripe=%u"},
1758         {Opt_delalloc, "delalloc"},
1759         {Opt_warn_on_error, "warn_on_error"},
1760         {Opt_nowarn_on_error, "nowarn_on_error"},
1761         {Opt_lazytime, "lazytime"},
1762         {Opt_nolazytime, "nolazytime"},
1763         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1764         {Opt_nodelalloc, "nodelalloc"},
1765         {Opt_removed, "mblk_io_submit"},
1766         {Opt_removed, "nomblk_io_submit"},
1767         {Opt_block_validity, "block_validity"},
1768         {Opt_noblock_validity, "noblock_validity"},
1769         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1770         {Opt_journal_ioprio, "journal_ioprio=%u"},
1771         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1772         {Opt_auto_da_alloc, "auto_da_alloc"},
1773         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1774         {Opt_dioread_nolock, "dioread_nolock"},
1775         {Opt_dioread_lock, "nodioread_nolock"},
1776         {Opt_dioread_lock, "dioread_lock"},
1777         {Opt_discard, "discard"},
1778         {Opt_nodiscard, "nodiscard"},
1779         {Opt_init_itable, "init_itable=%u"},
1780         {Opt_init_itable, "init_itable"},
1781         {Opt_noinit_itable, "noinit_itable"},
1782 #ifdef CONFIG_EXT4_DEBUG
1783         {Opt_fc_debug_force, "fc_debug_force"},
1784         {Opt_fc_debug_max_replay, "fc_debug_max_replay=%u"},
1785 #endif
1786         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1787         {Opt_test_dummy_encryption, "test_dummy_encryption=%s"},
1788         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1789         {Opt_inlinecrypt, "inlinecrypt"},
1790         {Opt_nombcache, "nombcache"},
1791         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1792         {Opt_removed, "prefetch_block_bitmaps"},
1793         {Opt_no_prefetch_block_bitmaps, "no_prefetch_block_bitmaps"},
1794         {Opt_mb_optimize_scan, "mb_optimize_scan=%d"},
1795         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1796         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1797         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1798         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1799         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1800         {Opt_err, NULL},
1801 };
1802
1803 static ext4_fsblk_t get_sb_block(void **data)
1804 {
1805         ext4_fsblk_t    sb_block;
1806         char            *options = (char *) *data;
1807
1808         if (!options || strncmp(options, "sb=", 3) != 0)
1809                 return 1;       /* Default location */
1810
1811         options += 3;
1812         /* TODO: use simple_strtoll with >32bit ext4 */
1813         sb_block = simple_strtoul(options, &options, 0);
1814         if (*options && *options != ',') {
1815                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1816                        (char *) *data);
1817                 return 1;
1818         }
1819         if (*options == ',')
1820                 options++;
1821         *data = (void *) options;
1822
1823         return sb_block;
1824 }
1825
1826 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1827 #define DEFAULT_MB_OPTIMIZE_SCAN        (-1)
1828
1829 static const char deprecated_msg[] =
1830         "Mount option \"%s\" will be removed by %s\n"
1831         "Contact [email protected] if you think we should keep it.\n";
1832
1833 #ifdef CONFIG_QUOTA
1834 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1835 {
1836         struct ext4_sb_info *sbi = EXT4_SB(sb);
1837         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1838         int ret = -1;
1839
1840         if (sb_any_quota_loaded(sb) && !old_qname) {
1841                 ext4_msg(sb, KERN_ERR,
1842                         "Cannot change journaled "
1843                         "quota options when quota turned on");
1844                 return -1;
1845         }
1846         if (ext4_has_feature_quota(sb)) {
1847                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1848                          "ignored when QUOTA feature is enabled");
1849                 return 1;
1850         }
1851         qname = match_strdup(args);
1852         if (!qname) {
1853                 ext4_msg(sb, KERN_ERR,
1854                         "Not enough memory for storing quotafile name");
1855                 return -1;
1856         }
1857         if (old_qname) {
1858                 if (strcmp(old_qname, qname) == 0)
1859                         ret = 1;
1860                 else
1861                         ext4_msg(sb, KERN_ERR,
1862                                  "%s quota file already specified",
1863                                  QTYPE2NAME(qtype));
1864                 goto errout;
1865         }
1866         if (strchr(qname, '/')) {
1867                 ext4_msg(sb, KERN_ERR,
1868                         "quotafile must be on filesystem root");
1869                 goto errout;
1870         }
1871         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1872         set_opt(sb, QUOTA);
1873         return 1;
1874 errout:
1875         kfree(qname);
1876         return ret;
1877 }
1878
1879 static int clear_qf_name(struct super_block *sb, int qtype)
1880 {
1881
1882         struct ext4_sb_info *sbi = EXT4_SB(sb);
1883         char *old_qname = get_qf_name(sb, sbi, qtype);
1884
1885         if (sb_any_quota_loaded(sb) && old_qname) {
1886                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1887                         " when quota turned on");
1888                 return -1;
1889         }
1890         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1891         synchronize_rcu();
1892         kfree(old_qname);
1893         return 1;
1894 }
1895 #endif
1896
1897 #define MOPT_SET        0x0001
1898 #define MOPT_CLEAR      0x0002
1899 #define MOPT_NOSUPPORT  0x0004
1900 #define MOPT_EXPLICIT   0x0008
1901 #define MOPT_CLEAR_ERR  0x0010
1902 #define MOPT_GTE0       0x0020
1903 #ifdef CONFIG_QUOTA
1904 #define MOPT_Q          0
1905 #define MOPT_QFMT       0x0040
1906 #else
1907 #define MOPT_Q          MOPT_NOSUPPORT
1908 #define MOPT_QFMT       MOPT_NOSUPPORT
1909 #endif
1910 #define MOPT_DATAJ      0x0080
1911 #define MOPT_NO_EXT2    0x0100
1912 #define MOPT_NO_EXT3    0x0200
1913 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1914 #define MOPT_STRING     0x0400
1915 #define MOPT_SKIP       0x0800
1916 #define MOPT_2          0x1000
1917
1918 static const struct mount_opts {
1919         int     token;
1920         int     mount_opt;
1921         int     flags;
1922 } ext4_mount_opts[] = {
1923         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1924         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1925         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1926         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1927         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1928         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1929         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1930          MOPT_EXT4_ONLY | MOPT_SET},
1931         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1932          MOPT_EXT4_ONLY | MOPT_CLEAR},
1933         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1934         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1935         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1936          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1937         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1938          MOPT_EXT4_ONLY | MOPT_CLEAR},
1939         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1940         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1941         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1942          MOPT_EXT4_ONLY | MOPT_CLEAR},
1943         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1944          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1945         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1946                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1947          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1948         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1949         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1950         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1951         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1952         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1953          MOPT_NO_EXT2},
1954         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1955          MOPT_NO_EXT2},
1956         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1957         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1958         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1959         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1960         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1961         {Opt_commit, 0, MOPT_GTE0},
1962         {Opt_max_batch_time, 0, MOPT_GTE0},
1963         {Opt_min_batch_time, 0, MOPT_GTE0},
1964         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1965         {Opt_init_itable, 0, MOPT_GTE0},
1966         {Opt_dax, EXT4_MOUNT_DAX_ALWAYS, MOPT_SET | MOPT_SKIP},
1967         {Opt_dax_always, EXT4_MOUNT_DAX_ALWAYS,
1968                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1969         {Opt_dax_inode, EXT4_MOUNT2_DAX_INODE,
1970                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1971         {Opt_dax_never, EXT4_MOUNT2_DAX_NEVER,
1972                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1973         {Opt_stripe, 0, MOPT_GTE0},
1974         {Opt_resuid, 0, MOPT_GTE0},
1975         {Opt_resgid, 0, MOPT_GTE0},
1976         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1977         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1978         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1979         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1980         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1981         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1982          MOPT_NO_EXT2 | MOPT_DATAJ},
1983         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1984         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1985 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1986         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1987         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1988 #else
1989         {Opt_acl, 0, MOPT_NOSUPPORT},
1990         {Opt_noacl, 0, MOPT_NOSUPPORT},
1991 #endif
1992         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1993         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1994         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1995         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1996         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1997                                                         MOPT_SET | MOPT_Q},
1998         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1999                                                         MOPT_SET | MOPT_Q},
2000         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
2001                                                         MOPT_SET | MOPT_Q},
2002         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2003                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
2004                                                         MOPT_CLEAR | MOPT_Q},
2005         {Opt_usrjquota, 0, MOPT_Q | MOPT_STRING},
2006         {Opt_grpjquota, 0, MOPT_Q | MOPT_STRING},
2007         {Opt_offusrjquota, 0, MOPT_Q},
2008         {Opt_offgrpjquota, 0, MOPT_Q},
2009         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
2010         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
2011         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
2012         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
2013         {Opt_test_dummy_encryption, 0, MOPT_STRING},
2014         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
2015         {Opt_no_prefetch_block_bitmaps, EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS,
2016          MOPT_SET},
2017         {Opt_mb_optimize_scan, EXT4_MOUNT2_MB_OPTIMIZE_SCAN, MOPT_GTE0},
2018 #ifdef CONFIG_EXT4_DEBUG
2019         {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
2020          MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
2021         {Opt_fc_debug_max_replay, 0, MOPT_GTE0},
2022 #endif
2023         {Opt_err, 0, 0}
2024 };
2025
2026 #ifdef CONFIG_UNICODE
2027 static const struct ext4_sb_encodings {
2028         __u16 magic;
2029         char *name;
2030         char *version;
2031 } ext4_sb_encoding_map[] = {
2032         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
2033 };
2034
2035 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
2036                                  const struct ext4_sb_encodings **encoding,
2037                                  __u16 *flags)
2038 {
2039         __u16 magic = le16_to_cpu(es->s_encoding);
2040         int i;
2041
2042         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
2043                 if (magic == ext4_sb_encoding_map[i].magic)
2044                         break;
2045
2046         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
2047                 return -EINVAL;
2048
2049         *encoding = &ext4_sb_encoding_map[i];
2050         *flags = le16_to_cpu(es->s_encoding_flags);
2051
2052         return 0;
2053 }
2054 #endif
2055
2056 static int ext4_set_test_dummy_encryption(struct super_block *sb,
2057                                           const char *opt,
2058                                           const substring_t *arg,
2059                                           bool is_remount)
2060 {
2061 #ifdef CONFIG_FS_ENCRYPTION
2062         struct ext4_sb_info *sbi = EXT4_SB(sb);
2063         int err;
2064
2065         /*
2066          * This mount option is just for testing, and it's not worthwhile to
2067          * implement the extra complexity (e.g. RCU protection) that would be
2068          * needed to allow it to be set or changed during remount.  We do allow
2069          * it to be specified during remount, but only if there is no change.
2070          */
2071         if (is_remount && !sbi->s_dummy_enc_policy.policy) {
2072                 ext4_msg(sb, KERN_WARNING,
2073                          "Can't set test_dummy_encryption on remount");
2074                 return -1;
2075         }
2076         err = fscrypt_set_test_dummy_encryption(sb, arg->from,
2077                                                 &sbi->s_dummy_enc_policy);
2078         if (err) {
2079                 if (err == -EEXIST)
2080                         ext4_msg(sb, KERN_WARNING,
2081                                  "Can't change test_dummy_encryption on remount");
2082                 else if (err == -EINVAL)
2083                         ext4_msg(sb, KERN_WARNING,
2084                                  "Value of option \"%s\" is unrecognized", opt);
2085                 else
2086                         ext4_msg(sb, KERN_WARNING,
2087                                  "Error processing option \"%s\" [%d]",
2088                                  opt, err);
2089                 return -1;
2090         }
2091         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2092 #else
2093         ext4_msg(sb, KERN_WARNING,
2094                  "Test dummy encryption mount option ignored");
2095 #endif
2096         return 1;
2097 }
2098
2099 struct ext4_parsed_options {
2100         unsigned long journal_devnum;
2101         unsigned int journal_ioprio;
2102         int mb_optimize_scan;
2103 };
2104
2105 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
2106                             substring_t *args, struct ext4_parsed_options *parsed_opts,
2107                             int is_remount)
2108 {
2109         struct ext4_sb_info *sbi = EXT4_SB(sb);
2110         const struct mount_opts *m;
2111         kuid_t uid;
2112         kgid_t gid;
2113         int arg = 0;
2114
2115 #ifdef CONFIG_QUOTA
2116         if (token == Opt_usrjquota)
2117                 return set_qf_name(sb, USRQUOTA, &args[0]);
2118         else if (token == Opt_grpjquota)
2119                 return set_qf_name(sb, GRPQUOTA, &args[0]);
2120         else if (token == Opt_offusrjquota)
2121                 return clear_qf_name(sb, USRQUOTA);
2122         else if (token == Opt_offgrpjquota)
2123                 return clear_qf_name(sb, GRPQUOTA);
2124 #endif
2125         switch (token) {
2126         case Opt_noacl:
2127         case Opt_nouser_xattr:
2128                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
2129                 break;
2130         case Opt_sb:
2131                 return 1;       /* handled by get_sb_block() */
2132         case Opt_removed:
2133                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
2134                 return 1;
2135         case Opt_abort:
2136                 ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
2137                 return 1;
2138         case Opt_i_version:
2139                 sb->s_flags |= SB_I_VERSION;
2140                 return 1;
2141         case Opt_lazytime:
2142                 sb->s_flags |= SB_LAZYTIME;
2143                 return 1;
2144         case Opt_nolazytime:
2145                 sb->s_flags &= ~SB_LAZYTIME;
2146                 return 1;
2147         case Opt_inlinecrypt:
2148 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2149                 sb->s_flags |= SB_INLINECRYPT;
2150 #else
2151                 ext4_msg(sb, KERN_ERR, "inline encryption not supported");
2152 #endif
2153                 return 1;
2154         }
2155
2156         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2157                 if (token == m->token)
2158                         break;
2159
2160         if (m->token == Opt_err) {
2161                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
2162                          "or missing value", opt);
2163                 return -1;
2164         }
2165
2166         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2167                 ext4_msg(sb, KERN_ERR,
2168                          "Mount option \"%s\" incompatible with ext2", opt);
2169                 return -1;
2170         }
2171         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2172                 ext4_msg(sb, KERN_ERR,
2173                          "Mount option \"%s\" incompatible with ext3", opt);
2174                 return -1;
2175         }
2176
2177         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
2178                 return -1;
2179         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
2180                 return -1;
2181         if (m->flags & MOPT_EXPLICIT) {
2182                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2183                         set_opt2(sb, EXPLICIT_DELALLOC);
2184                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2185                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
2186                 } else
2187                         return -1;
2188         }
2189         if (m->flags & MOPT_CLEAR_ERR)
2190                 clear_opt(sb, ERRORS_MASK);
2191         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
2192                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
2193                          "options when quota turned on");
2194                 return -1;
2195         }
2196
2197         if (m->flags & MOPT_NOSUPPORT) {
2198                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
2199         } else if (token == Opt_commit) {
2200                 if (arg == 0)
2201                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
2202                 else if (arg > INT_MAX / HZ) {
2203                         ext4_msg(sb, KERN_ERR,
2204                                  "Invalid commit interval %d, "
2205                                  "must be smaller than %d",
2206                                  arg, INT_MAX / HZ);
2207                         return -1;
2208                 }
2209                 sbi->s_commit_interval = HZ * arg;
2210         } else if (token == Opt_debug_want_extra_isize) {
2211                 if ((arg & 1) ||
2212                     (arg < 4) ||
2213                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
2214                         ext4_msg(sb, KERN_ERR,
2215                                  "Invalid want_extra_isize %d", arg);
2216                         return -1;
2217                 }
2218                 sbi->s_want_extra_isize = arg;
2219         } else if (token == Opt_max_batch_time) {
2220                 sbi->s_max_batch_time = arg;
2221         } else if (token == Opt_min_batch_time) {
2222                 sbi->s_min_batch_time = arg;
2223         } else if (token == Opt_inode_readahead_blks) {
2224                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
2225                         ext4_msg(sb, KERN_ERR,
2226                                  "EXT4-fs: inode_readahead_blks must be "
2227                                  "0 or a power of 2 smaller than 2^31");
2228                         return -1;
2229                 }
2230                 sbi->s_inode_readahead_blks = arg;
2231         } else if (token == Opt_init_itable) {
2232                 set_opt(sb, INIT_INODE_TABLE);
2233                 if (!args->from)
2234                         arg = EXT4_DEF_LI_WAIT_MULT;
2235                 sbi->s_li_wait_mult = arg;
2236         } else if (token == Opt_max_dir_size_kb) {
2237                 sbi->s_max_dir_size_kb = arg;
2238 #ifdef CONFIG_EXT4_DEBUG
2239         } else if (token == Opt_fc_debug_max_replay) {
2240                 sbi->s_fc_debug_max_replay = arg;
2241 #endif
2242         } else if (token == Opt_stripe) {
2243                 sbi->s_stripe = arg;
2244         } else if (token == Opt_resuid) {
2245                 uid = make_kuid(current_user_ns(), arg);
2246                 if (!uid_valid(uid)) {
2247                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
2248                         return -1;
2249                 }
2250                 sbi->s_resuid = uid;
2251         } else if (token == Opt_resgid) {
2252                 gid = make_kgid(current_user_ns(), arg);
2253                 if (!gid_valid(gid)) {
2254                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
2255                         return -1;
2256                 }
2257                 sbi->s_resgid = gid;
2258         } else if (token == Opt_journal_dev) {
2259                 if (is_remount) {
2260                         ext4_msg(sb, KERN_ERR,
2261                                  "Cannot specify journal on remount");
2262                         return -1;
2263                 }
2264                 parsed_opts->journal_devnum = arg;
2265         } else if (token == Opt_journal_path) {
2266                 char *journal_path;
2267                 struct inode *journal_inode;
2268                 struct path path;
2269                 int error;
2270
2271                 if (is_remount) {
2272                         ext4_msg(sb, KERN_ERR,
2273                                  "Cannot specify journal on remount");
2274                         return -1;
2275                 }
2276                 journal_path = match_strdup(&args[0]);
2277                 if (!journal_path) {
2278                         ext4_msg(sb, KERN_ERR, "error: could not dup "
2279                                 "journal device string");
2280                         return -1;
2281                 }
2282
2283                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2284                 if (error) {
2285                         ext4_msg(sb, KERN_ERR, "error: could not find "
2286                                 "journal device path: error %d", error);
2287                         kfree(journal_path);
2288                         return -1;
2289                 }
2290
2291                 journal_inode = d_inode(path.dentry);
2292                 if (!S_ISBLK(journal_inode->i_mode)) {
2293                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
2294                                 "is not a block device", journal_path);
2295                         path_put(&path);
2296                         kfree(journal_path);
2297                         return -1;
2298                 }
2299
2300                 parsed_opts->journal_devnum = new_encode_dev(journal_inode->i_rdev);
2301                 path_put(&path);
2302                 kfree(journal_path);
2303         } else if (token == Opt_journal_ioprio) {
2304                 if (arg > 7) {
2305                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2306                                  " (must be 0-7)");
2307                         return -1;
2308                 }
2309                 parsed_opts->journal_ioprio =
2310                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2311         } else if (token == Opt_test_dummy_encryption) {
2312                 return ext4_set_test_dummy_encryption(sb, opt, &args[0],
2313                                                       is_remount);
2314         } else if (m->flags & MOPT_DATAJ) {
2315                 if (is_remount) {
2316                         if (!sbi->s_journal)
2317                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2318                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2319                                 ext4_msg(sb, KERN_ERR,
2320                                          "Cannot change data mode on remount");
2321                                 return -1;
2322                         }
2323                 } else {
2324                         clear_opt(sb, DATA_FLAGS);
2325                         sbi->s_mount_opt |= m->mount_opt;
2326                 }
2327 #ifdef CONFIG_QUOTA
2328         } else if (m->flags & MOPT_QFMT) {
2329                 if (sb_any_quota_loaded(sb) &&
2330                     sbi->s_jquota_fmt != m->mount_opt) {
2331                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2332                                  "quota options when quota turned on");
2333                         return -1;
2334                 }
2335                 if (ext4_has_feature_quota(sb)) {
2336                         ext4_msg(sb, KERN_INFO,
2337                                  "Quota format mount options ignored "
2338                                  "when QUOTA feature is enabled");
2339                         return 1;
2340                 }
2341                 sbi->s_jquota_fmt = m->mount_opt;
2342 #endif
2343         } else if (token == Opt_dax || token == Opt_dax_always ||
2344                    token == Opt_dax_inode || token == Opt_dax_never) {
2345 #ifdef CONFIG_FS_DAX
2346                 switch (token) {
2347                 case Opt_dax:
2348                 case Opt_dax_always:
2349                         if (is_remount &&
2350                             (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2351                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2352                         fail_dax_change_remount:
2353                                 ext4_msg(sb, KERN_ERR, "can't change "
2354                                          "dax mount option while remounting");
2355                                 return -1;
2356                         }
2357                         if (is_remount &&
2358                             (test_opt(sb, DATA_FLAGS) ==
2359                              EXT4_MOUNT_JOURNAL_DATA)) {
2360                                     ext4_msg(sb, KERN_ERR, "can't mount with "
2361                                              "both data=journal and dax");
2362                                     return -1;
2363                         }
2364                         ext4_msg(sb, KERN_WARNING,
2365                                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2366                         sbi->s_mount_opt |= EXT4_MOUNT_DAX_ALWAYS;
2367                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2368                         break;
2369                 case Opt_dax_never:
2370                         if (is_remount &&
2371                             (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2372                              (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS)))
2373                                 goto fail_dax_change_remount;
2374                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2375                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2376                         break;
2377                 case Opt_dax_inode:
2378                         if (is_remount &&
2379                             ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2380                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2381                              !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE)))
2382                                 goto fail_dax_change_remount;
2383                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2384                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2385                         /* Strictly for printing options */
2386                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_INODE;
2387                         break;
2388                 }
2389 #else
2390                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2391                 sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2392                 sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2393                 return -1;
2394 #endif
2395         } else if (token == Opt_data_err_abort) {
2396                 sbi->s_mount_opt |= m->mount_opt;
2397         } else if (token == Opt_data_err_ignore) {
2398                 sbi->s_mount_opt &= ~m->mount_opt;
2399         } else if (token == Opt_mb_optimize_scan) {
2400                 if (arg != 0 && arg != 1) {
2401                         ext4_msg(sb, KERN_WARNING,
2402                                  "mb_optimize_scan should be set to 0 or 1.");
2403                         return -1;
2404                 }
2405                 parsed_opts->mb_optimize_scan = arg;
2406         } else {
2407                 if (!args->from)
2408                         arg = 1;
2409                 if (m->flags & MOPT_CLEAR)
2410                         arg = !arg;
2411                 else if (unlikely(!(m->flags & MOPT_SET))) {
2412                         ext4_msg(sb, KERN_WARNING,
2413                                  "buggy handling of option %s", opt);
2414                         WARN_ON(1);
2415                         return -1;
2416                 }
2417                 if (m->flags & MOPT_2) {
2418                         if (arg != 0)
2419                                 sbi->s_mount_opt2 |= m->mount_opt;
2420                         else
2421                                 sbi->s_mount_opt2 &= ~m->mount_opt;
2422                 } else {
2423                         if (arg != 0)
2424                                 sbi->s_mount_opt |= m->mount_opt;
2425                         else
2426                                 sbi->s_mount_opt &= ~m->mount_opt;
2427                 }
2428         }
2429         return 1;
2430 }
2431
2432 static int parse_options(char *options, struct super_block *sb,
2433                          struct ext4_parsed_options *ret_opts,
2434                          int is_remount)
2435 {
2436         struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2437         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2438         substring_t args[MAX_OPT_ARGS];
2439         int token;
2440
2441         if (!options)
2442                 return 1;
2443
2444         while ((p = strsep(&options, ",")) != NULL) {
2445                 if (!*p)
2446                         continue;
2447                 /*
2448                  * Initialize args struct so we know whether arg was
2449                  * found; some options take optional arguments.
2450                  */
2451                 args[0].to = args[0].from = NULL;
2452                 token = match_token(p, tokens, args);
2453                 if (handle_mount_opt(sb, p, token, args, ret_opts,
2454                                      is_remount) < 0)
2455                         return 0;
2456         }
2457 #ifdef CONFIG_QUOTA
2458         /*
2459          * We do the test below only for project quotas. 'usrquota' and
2460          * 'grpquota' mount options are allowed even without quota feature
2461          * to support legacy quotas in quota files.
2462          */
2463         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2464                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2465                          "Cannot enable project quota enforcement.");
2466                 return 0;
2467         }
2468         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2469         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2470         if (usr_qf_name || grp_qf_name) {
2471                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2472                         clear_opt(sb, USRQUOTA);
2473
2474                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2475                         clear_opt(sb, GRPQUOTA);
2476
2477                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2478                         ext4_msg(sb, KERN_ERR, "old and new quota "
2479                                         "format mixing");
2480                         return 0;
2481                 }
2482
2483                 if (!sbi->s_jquota_fmt) {
2484                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2485                                         "not specified");
2486                         return 0;
2487                 }
2488         }
2489 #endif
2490         if (test_opt(sb, DIOREAD_NOLOCK)) {
2491                 int blocksize =
2492                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2493                 if (blocksize < PAGE_SIZE)
2494                         ext4_msg(sb, KERN_WARNING, "Warning: mounting with an "
2495                                  "experimental mount option 'dioread_nolock' "
2496                                  "for blocksize < PAGE_SIZE");
2497         }
2498         return 1;
2499 }
2500
2501 static inline void ext4_show_quota_options(struct seq_file *seq,
2502                                            struct super_block *sb)
2503 {
2504 #if defined(CONFIG_QUOTA)
2505         struct ext4_sb_info *sbi = EXT4_SB(sb);
2506         char *usr_qf_name, *grp_qf_name;
2507
2508         if (sbi->s_jquota_fmt) {
2509                 char *fmtname = "";
2510
2511                 switch (sbi->s_jquota_fmt) {
2512                 case QFMT_VFS_OLD:
2513                         fmtname = "vfsold";
2514                         break;
2515                 case QFMT_VFS_V0:
2516                         fmtname = "vfsv0";
2517                         break;
2518                 case QFMT_VFS_V1:
2519                         fmtname = "vfsv1";
2520                         break;
2521                 }
2522                 seq_printf(seq, ",jqfmt=%s", fmtname);
2523         }
2524
2525         rcu_read_lock();
2526         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2527         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2528         if (usr_qf_name)
2529                 seq_show_option(seq, "usrjquota", usr_qf_name);
2530         if (grp_qf_name)
2531                 seq_show_option(seq, "grpjquota", grp_qf_name);
2532         rcu_read_unlock();
2533 #endif
2534 }
2535
2536 static const char *token2str(int token)
2537 {
2538         const struct match_token *t;
2539
2540         for (t = tokens; t->token != Opt_err; t++)
2541                 if (t->token == token && !strchr(t->pattern, '='))
2542                         break;
2543         return t->pattern;
2544 }
2545
2546 /*
2547  * Show an option if
2548  *  - it's set to a non-default value OR
2549  *  - if the per-sb default is different from the global default
2550  */
2551 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2552                               int nodefs)
2553 {
2554         struct ext4_sb_info *sbi = EXT4_SB(sb);
2555         struct ext4_super_block *es = sbi->s_es;
2556         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2557         const struct mount_opts *m;
2558         char sep = nodefs ? '\n' : ',';
2559
2560 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2561 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2562
2563         if (sbi->s_sb_block != 1)
2564                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2565
2566         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2567                 int want_set = m->flags & MOPT_SET;
2568                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2569                     (m->flags & MOPT_CLEAR_ERR) || m->flags & MOPT_SKIP)
2570                         continue;
2571                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2572                         continue; /* skip if same as the default */
2573                 if ((want_set &&
2574                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2575                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2576                         continue; /* select Opt_noFoo vs Opt_Foo */
2577                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2578         }
2579
2580         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2581             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2582                 SEQ_OPTS_PRINT("resuid=%u",
2583                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2584         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2585             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2586                 SEQ_OPTS_PRINT("resgid=%u",
2587                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2588         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2589         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2590                 SEQ_OPTS_PUTS("errors=remount-ro");
2591         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2592                 SEQ_OPTS_PUTS("errors=continue");
2593         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2594                 SEQ_OPTS_PUTS("errors=panic");
2595         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2596                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2597         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2598                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2599         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2600                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2601         if (sb->s_flags & SB_I_VERSION)
2602                 SEQ_OPTS_PUTS("i_version");
2603         if (nodefs || sbi->s_stripe)
2604                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2605         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2606                         (sbi->s_mount_opt ^ def_mount_opt)) {
2607                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2608                         SEQ_OPTS_PUTS("data=journal");
2609                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2610                         SEQ_OPTS_PUTS("data=ordered");
2611                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2612                         SEQ_OPTS_PUTS("data=writeback");
2613         }
2614         if (nodefs ||
2615             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2616                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2617                                sbi->s_inode_readahead_blks);
2618
2619         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2620                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2621                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2622         if (nodefs || sbi->s_max_dir_size_kb)
2623                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2624         if (test_opt(sb, DATA_ERR_ABORT))
2625                 SEQ_OPTS_PUTS("data_err=abort");
2626
2627         fscrypt_show_test_dummy_encryption(seq, sep, sb);
2628
2629         if (sb->s_flags & SB_INLINECRYPT)
2630                 SEQ_OPTS_PUTS("inlinecrypt");
2631
2632         if (test_opt(sb, DAX_ALWAYS)) {
2633                 if (IS_EXT2_SB(sb))
2634                         SEQ_OPTS_PUTS("dax");
2635                 else
2636                         SEQ_OPTS_PUTS("dax=always");
2637         } else if (test_opt2(sb, DAX_NEVER)) {
2638                 SEQ_OPTS_PUTS("dax=never");
2639         } else if (test_opt2(sb, DAX_INODE)) {
2640                 SEQ_OPTS_PUTS("dax=inode");
2641         }
2642         ext4_show_quota_options(seq, sb);
2643         return 0;
2644 }
2645
2646 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2647 {
2648         return _ext4_show_options(seq, root->d_sb, 0);
2649 }
2650
2651 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2652 {
2653         struct super_block *sb = seq->private;
2654         int rc;
2655
2656         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2657         rc = _ext4_show_options(seq, sb, 1);
2658         seq_puts(seq, "\n");
2659         return rc;
2660 }
2661
2662 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2663                             int read_only)
2664 {
2665         struct ext4_sb_info *sbi = EXT4_SB(sb);
2666         int err = 0;
2667
2668         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2669                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2670                          "forcing read-only mode");
2671                 err = -EROFS;
2672                 goto done;
2673         }
2674         if (read_only)
2675                 goto done;
2676         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2677                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2678                          "running e2fsck is recommended");
2679         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2680                 ext4_msg(sb, KERN_WARNING,
2681                          "warning: mounting fs with errors, "
2682                          "running e2fsck is recommended");
2683         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2684                  le16_to_cpu(es->s_mnt_count) >=
2685                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2686                 ext4_msg(sb, KERN_WARNING,
2687                          "warning: maximal mount count reached, "
2688                          "running e2fsck is recommended");
2689         else if (le32_to_cpu(es->s_checkinterval) &&
2690                  (ext4_get_tstamp(es, s_lastcheck) +
2691                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2692                 ext4_msg(sb, KERN_WARNING,
2693                          "warning: checktime reached, "
2694                          "running e2fsck is recommended");
2695         if (!sbi->s_journal)
2696                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2697         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2698                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2699         le16_add_cpu(&es->s_mnt_count, 1);
2700         ext4_update_tstamp(es, s_mtime);
2701         if (sbi->s_journal)
2702                 ext4_set_feature_journal_needs_recovery(sb);
2703
2704         err = ext4_commit_super(sb);
2705 done:
2706         if (test_opt(sb, DEBUG))
2707                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2708                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2709                         sb->s_blocksize,
2710                         sbi->s_groups_count,
2711                         EXT4_BLOCKS_PER_GROUP(sb),
2712                         EXT4_INODES_PER_GROUP(sb),
2713                         sbi->s_mount_opt, sbi->s_mount_opt2);
2714
2715         cleancache_init_fs(sb);
2716         return err;
2717 }
2718
2719 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2720 {
2721         struct ext4_sb_info *sbi = EXT4_SB(sb);
2722         struct flex_groups **old_groups, **new_groups;
2723         int size, i, j;
2724
2725         if (!sbi->s_log_groups_per_flex)
2726                 return 0;
2727
2728         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2729         if (size <= sbi->s_flex_groups_allocated)
2730                 return 0;
2731
2732         new_groups = kvzalloc(roundup_pow_of_two(size *
2733                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2734         if (!new_groups) {
2735                 ext4_msg(sb, KERN_ERR,
2736                          "not enough memory for %d flex group pointers", size);
2737                 return -ENOMEM;
2738         }
2739         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2740                 new_groups[i] = kvzalloc(roundup_pow_of_two(
2741                                          sizeof(struct flex_groups)),
2742                                          GFP_KERNEL);
2743                 if (!new_groups[i]) {
2744                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
2745                                 kvfree(new_groups[j]);
2746                         kvfree(new_groups);
2747                         ext4_msg(sb, KERN_ERR,
2748                                  "not enough memory for %d flex groups", size);
2749                         return -ENOMEM;
2750                 }
2751         }
2752         rcu_read_lock();
2753         old_groups = rcu_dereference(sbi->s_flex_groups);
2754         if (old_groups)
2755                 memcpy(new_groups, old_groups,
2756                        (sbi->s_flex_groups_allocated *
2757                         sizeof(struct flex_groups *)));
2758         rcu_read_unlock();
2759         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2760         sbi->s_flex_groups_allocated = size;
2761         if (old_groups)
2762                 ext4_kvfree_array_rcu(old_groups);
2763         return 0;
2764 }
2765
2766 static int ext4_fill_flex_info(struct super_block *sb)
2767 {
2768         struct ext4_sb_info *sbi = EXT4_SB(sb);
2769         struct ext4_group_desc *gdp = NULL;
2770         struct flex_groups *fg;
2771         ext4_group_t flex_group;
2772         int i, err;
2773
2774         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2775         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2776                 sbi->s_log_groups_per_flex = 0;
2777                 return 1;
2778         }
2779
2780         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2781         if (err)
2782                 goto failed;
2783
2784         for (i = 0; i < sbi->s_groups_count; i++) {
2785                 gdp = ext4_get_group_desc(sb, i, NULL);
2786
2787                 flex_group = ext4_flex_group(sbi, i);
2788                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2789                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2790                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2791                              &fg->free_clusters);
2792                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2793         }
2794
2795         return 1;
2796 failed:
2797         return 0;
2798 }
2799
2800 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2801                                    struct ext4_group_desc *gdp)
2802 {
2803         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2804         __u16 crc = 0;
2805         __le32 le_group = cpu_to_le32(block_group);
2806         struct ext4_sb_info *sbi = EXT4_SB(sb);
2807
2808         if (ext4_has_metadata_csum(sbi->s_sb)) {
2809                 /* Use new metadata_csum algorithm */
2810                 __u32 csum32;
2811                 __u16 dummy_csum = 0;
2812
2813                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2814                                      sizeof(le_group));
2815                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2816                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2817                                      sizeof(dummy_csum));
2818                 offset += sizeof(dummy_csum);
2819                 if (offset < sbi->s_desc_size)
2820                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2821                                              sbi->s_desc_size - offset);
2822
2823                 crc = csum32 & 0xFFFF;
2824                 goto out;
2825         }
2826
2827         /* old crc16 code */
2828         if (!ext4_has_feature_gdt_csum(sb))
2829                 return 0;
2830
2831         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2832         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2833         crc = crc16(crc, (__u8 *)gdp, offset);
2834         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2835         /* for checksum of struct ext4_group_desc do the rest...*/
2836         if (ext4_has_feature_64bit(sb) &&
2837             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2838                 crc = crc16(crc, (__u8 *)gdp + offset,
2839                             le16_to_cpu(sbi->s_es->s_desc_size) -
2840                                 offset);
2841
2842 out:
2843         return cpu_to_le16(crc);
2844 }
2845
2846 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2847                                 struct ext4_group_desc *gdp)
2848 {
2849         if (ext4_has_group_desc_csum(sb) &&
2850             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2851                 return 0;
2852
2853         return 1;
2854 }
2855
2856 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2857                               struct ext4_group_desc *gdp)
2858 {
2859         if (!ext4_has_group_desc_csum(sb))
2860                 return;
2861         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2862 }
2863
2864 /* Called at mount-time, super-block is locked */
2865 static int ext4_check_descriptors(struct super_block *sb,
2866                                   ext4_fsblk_t sb_block,
2867                                   ext4_group_t *first_not_zeroed)
2868 {
2869         struct ext4_sb_info *sbi = EXT4_SB(sb);
2870         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2871         ext4_fsblk_t last_block;
2872         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2873         ext4_fsblk_t block_bitmap;
2874         ext4_fsblk_t inode_bitmap;
2875         ext4_fsblk_t inode_table;
2876         int flexbg_flag = 0;
2877         ext4_group_t i, grp = sbi->s_groups_count;
2878
2879         if (ext4_has_feature_flex_bg(sb))
2880                 flexbg_flag = 1;
2881
2882         ext4_debug("Checking group descriptors");
2883
2884         for (i = 0; i < sbi->s_groups_count; i++) {
2885                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2886
2887                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2888                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2889                 else
2890                         last_block = first_block +
2891                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2892
2893                 if ((grp == sbi->s_groups_count) &&
2894                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2895                         grp = i;
2896
2897                 block_bitmap = ext4_block_bitmap(sb, gdp);
2898                 if (block_bitmap == sb_block) {
2899                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2900                                  "Block bitmap for group %u overlaps "
2901                                  "superblock", i);
2902                         if (!sb_rdonly(sb))
2903                                 return 0;
2904                 }
2905                 if (block_bitmap >= sb_block + 1 &&
2906                     block_bitmap <= last_bg_block) {
2907                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2908                                  "Block bitmap for group %u overlaps "
2909                                  "block group descriptors", i);
2910                         if (!sb_rdonly(sb))
2911                                 return 0;
2912                 }
2913                 if (block_bitmap < first_block || block_bitmap > last_block) {
2914                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2915                                "Block bitmap for group %u not in group "
2916                                "(block %llu)!", i, block_bitmap);
2917                         return 0;
2918                 }
2919                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2920                 if (inode_bitmap == sb_block) {
2921                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2922                                  "Inode bitmap for group %u overlaps "
2923                                  "superblock", i);
2924                         if (!sb_rdonly(sb))
2925                                 return 0;
2926                 }
2927                 if (inode_bitmap >= sb_block + 1 &&
2928                     inode_bitmap <= last_bg_block) {
2929                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2930                                  "Inode bitmap for group %u overlaps "
2931                                  "block group descriptors", i);
2932                         if (!sb_rdonly(sb))
2933                                 return 0;
2934                 }
2935                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2936                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2937                                "Inode bitmap for group %u not in group "
2938                                "(block %llu)!", i, inode_bitmap);
2939                         return 0;
2940                 }
2941                 inode_table = ext4_inode_table(sb, gdp);
2942                 if (inode_table == sb_block) {
2943                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2944                                  "Inode table for group %u overlaps "
2945                                  "superblock", i);
2946                         if (!sb_rdonly(sb))
2947                                 return 0;
2948                 }
2949                 if (inode_table >= sb_block + 1 &&
2950                     inode_table <= last_bg_block) {
2951                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2952                                  "Inode table for group %u overlaps "
2953                                  "block group descriptors", i);
2954                         if (!sb_rdonly(sb))
2955                                 return 0;
2956                 }
2957                 if (inode_table < first_block ||
2958                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2959                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2960                                "Inode table for group %u not in group "
2961                                "(block %llu)!", i, inode_table);
2962                         return 0;
2963                 }
2964                 ext4_lock_group(sb, i);
2965                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2966                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2967                                  "Checksum for group %u failed (%u!=%u)",
2968                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2969                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2970                         if (!sb_rdonly(sb)) {
2971                                 ext4_unlock_group(sb, i);
2972                                 return 0;
2973                         }
2974                 }
2975                 ext4_unlock_group(sb, i);
2976                 if (!flexbg_flag)
2977                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2978         }
2979         if (NULL != first_not_zeroed)
2980                 *first_not_zeroed = grp;
2981         return 1;
2982 }
2983
2984 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2985  * the superblock) which were deleted from all directories, but held open by
2986  * a process at the time of a crash.  We walk the list and try to delete these
2987  * inodes at recovery time (only with a read-write filesystem).
2988  *
2989  * In order to keep the orphan inode chain consistent during traversal (in
2990  * case of crash during recovery), we link each inode into the superblock
2991  * orphan list_head and handle it the same way as an inode deletion during
2992  * normal operation (which journals the operations for us).
2993  *
2994  * We only do an iget() and an iput() on each inode, which is very safe if we
2995  * accidentally point at an in-use or already deleted inode.  The worst that
2996  * can happen in this case is that we get a "bit already cleared" message from
2997  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2998  * e2fsck was run on this filesystem, and it must have already done the orphan
2999  * inode cleanup for us, so we can safely abort without any further action.
3000  */
3001 static void ext4_orphan_cleanup(struct super_block *sb,
3002                                 struct ext4_super_block *es)
3003 {
3004         unsigned int s_flags = sb->s_flags;
3005         int ret, nr_orphans = 0, nr_truncates = 0;
3006 #ifdef CONFIG_QUOTA
3007         int quota_update = 0;
3008         int i;
3009 #endif
3010         if (!es->s_last_orphan) {
3011                 jbd_debug(4, "no orphan inodes to clean up\n");
3012                 return;
3013         }
3014
3015         if (bdev_read_only(sb->s_bdev)) {
3016                 ext4_msg(sb, KERN_ERR, "write access "
3017                         "unavailable, skipping orphan cleanup");
3018                 return;
3019         }
3020
3021         /* Check if feature set would not allow a r/w mount */
3022         if (!ext4_feature_set_ok(sb, 0)) {
3023                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
3024                          "unknown ROCOMPAT features");
3025                 return;
3026         }
3027
3028         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
3029                 /* don't clear list on RO mount w/ errors */
3030                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
3031                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
3032                                   "clearing orphan list.\n");
3033                         es->s_last_orphan = 0;
3034                 }
3035                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
3036                 return;
3037         }
3038
3039         if (s_flags & SB_RDONLY) {
3040                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
3041                 sb->s_flags &= ~SB_RDONLY;
3042         }
3043 #ifdef CONFIG_QUOTA
3044         /*
3045          * Turn on quotas which were not enabled for read-only mounts if
3046          * filesystem has quota feature, so that they are updated correctly.
3047          */
3048         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
3049                 int ret = ext4_enable_quotas(sb);
3050
3051                 if (!ret)
3052                         quota_update = 1;
3053                 else
3054                         ext4_msg(sb, KERN_ERR,
3055                                 "Cannot turn on quotas: error %d", ret);
3056         }
3057
3058         /* Turn on journaled quotas used for old sytle */
3059         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3060                 if (EXT4_SB(sb)->s_qf_names[i]) {
3061                         int ret = ext4_quota_on_mount(sb, i);
3062
3063                         if (!ret)
3064                                 quota_update = 1;
3065                         else
3066                                 ext4_msg(sb, KERN_ERR,
3067                                         "Cannot turn on journaled "
3068                                         "quota: type %d: error %d", i, ret);
3069                 }
3070         }
3071 #endif
3072
3073         while (es->s_last_orphan) {
3074                 struct inode *inode;
3075
3076                 /*
3077                  * We may have encountered an error during cleanup; if
3078                  * so, skip the rest.
3079                  */
3080                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
3081                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
3082                         es->s_last_orphan = 0;
3083                         break;
3084                 }
3085
3086                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
3087                 if (IS_ERR(inode)) {
3088                         es->s_last_orphan = 0;
3089                         break;
3090                 }
3091
3092                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
3093                 dquot_initialize(inode);
3094                 if (inode->i_nlink) {
3095                         if (test_opt(sb, DEBUG))
3096                                 ext4_msg(sb, KERN_DEBUG,
3097                                         "%s: truncating inode %lu to %lld bytes",
3098                                         __func__, inode->i_ino, inode->i_size);
3099                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
3100                                   inode->i_ino, inode->i_size);
3101                         inode_lock(inode);
3102                         truncate_inode_pages(inode->i_mapping, inode->i_size);
3103                         ret = ext4_truncate(inode);
3104                         if (ret)
3105                                 ext4_std_error(inode->i_sb, ret);
3106                         inode_unlock(inode);
3107                         nr_truncates++;
3108                 } else {
3109                         if (test_opt(sb, DEBUG))
3110                                 ext4_msg(sb, KERN_DEBUG,
3111                                         "%s: deleting unreferenced inode %lu",
3112                                         __func__, inode->i_ino);
3113                         jbd_debug(2, "deleting unreferenced inode %lu\n",
3114                                   inode->i_ino);
3115                         nr_orphans++;
3116                 }
3117                 iput(inode);  /* The delete magic happens here! */
3118         }
3119
3120 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
3121
3122         if (nr_orphans)
3123                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
3124                        PLURAL(nr_orphans));
3125         if (nr_truncates)
3126                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
3127                        PLURAL(nr_truncates));
3128 #ifdef CONFIG_QUOTA
3129         /* Turn off quotas if they were enabled for orphan cleanup */
3130         if (quota_update) {
3131                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3132                         if (sb_dqopt(sb)->files[i])
3133                                 dquot_quota_off(sb, i);
3134                 }
3135         }
3136 #endif
3137         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
3138 }
3139
3140 /*
3141  * Maximal extent format file size.
3142  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3143  * extent format containers, within a sector_t, and within i_blocks
3144  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3145  * so that won't be a limiting factor.
3146  *
3147  * However there is other limiting factor. We do store extents in the form
3148  * of starting block and length, hence the resulting length of the extent
3149  * covering maximum file size must fit into on-disk format containers as
3150  * well. Given that length is always by 1 unit bigger than max unit (because
3151  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3152  *
3153  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3154  */
3155 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3156 {
3157         loff_t res;
3158         loff_t upper_limit = MAX_LFS_FILESIZE;
3159
3160         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3161
3162         if (!has_huge_files) {
3163                 upper_limit = (1LL << 32) - 1;
3164
3165                 /* total blocks in file system block size */
3166                 upper_limit >>= (blkbits - 9);
3167                 upper_limit <<= blkbits;
3168         }
3169
3170         /*
3171          * 32-bit extent-start container, ee_block. We lower the maxbytes
3172          * by one fs block, so ee_len can cover the extent of maximum file
3173          * size
3174          */
3175         res = (1LL << 32) - 1;
3176         res <<= blkbits;
3177
3178         /* Sanity check against vm- & vfs- imposed limits */
3179         if (res > upper_limit)
3180                 res = upper_limit;
3181
3182         return res;
3183 }
3184
3185 /*
3186  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3187  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3188  * We need to be 1 filesystem block less than the 2^48 sector limit.
3189  */
3190 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3191 {
3192         loff_t res = EXT4_NDIR_BLOCKS;
3193         int meta_blocks;
3194         loff_t upper_limit;
3195         /* This is calculated to be the largest file size for a dense, block
3196          * mapped file such that the file's total number of 512-byte sectors,
3197          * including data and all indirect blocks, does not exceed (2^48 - 1).
3198          *
3199          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3200          * number of 512-byte sectors of the file.
3201          */
3202
3203         if (!has_huge_files) {
3204                 /*
3205                  * !has_huge_files or implies that the inode i_block field
3206                  * represents total file blocks in 2^32 512-byte sectors ==
3207                  * size of vfs inode i_blocks * 8
3208                  */
3209                 upper_limit = (1LL << 32) - 1;
3210
3211                 /* total blocks in file system block size */
3212                 upper_limit >>= (bits - 9);
3213
3214         } else {
3215                 /*
3216                  * We use 48 bit ext4_inode i_blocks
3217                  * With EXT4_HUGE_FILE_FL set the i_blocks
3218                  * represent total number of blocks in
3219                  * file system block size
3220                  */
3221                 upper_limit = (1LL << 48) - 1;
3222
3223         }
3224
3225         /* indirect blocks */
3226         meta_blocks = 1;
3227         /* double indirect blocks */
3228         meta_blocks += 1 + (1LL << (bits-2));
3229         /* tripple indirect blocks */
3230         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
3231
3232         upper_limit -= meta_blocks;
3233         upper_limit <<= bits;
3234
3235         res += 1LL << (bits-2);
3236         res += 1LL << (2*(bits-2));
3237         res += 1LL << (3*(bits-2));
3238         res <<= bits;
3239         if (res > upper_limit)
3240                 res = upper_limit;
3241
3242         if (res > MAX_LFS_FILESIZE)
3243                 res = MAX_LFS_FILESIZE;
3244
3245         return res;
3246 }
3247
3248 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3249                                    ext4_fsblk_t logical_sb_block, int nr)
3250 {
3251         struct ext4_sb_info *sbi = EXT4_SB(sb);
3252         ext4_group_t bg, first_meta_bg;
3253         int has_super = 0;
3254
3255         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3256
3257         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3258                 return logical_sb_block + nr + 1;
3259         bg = sbi->s_desc_per_block * nr;
3260         if (ext4_bg_has_super(sb, bg))
3261                 has_super = 1;
3262
3263         /*
3264          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3265          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3266          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3267          * compensate.
3268          */
3269         if (sb->s_blocksize == 1024 && nr == 0 &&
3270             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3271                 has_super++;
3272
3273         return (has_super + ext4_group_first_block_no(sb, bg));
3274 }
3275
3276 /**
3277  * ext4_get_stripe_size: Get the stripe size.
3278  * @sbi: In memory super block info
3279  *
3280  * If we have specified it via mount option, then
3281  * use the mount option value. If the value specified at mount time is
3282  * greater than the blocks per group use the super block value.
3283  * If the super block value is greater than blocks per group return 0.
3284  * Allocator needs it be less than blocks per group.
3285  *
3286  */
3287 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3288 {
3289         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3290         unsigned long stripe_width =
3291                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3292         int ret;
3293
3294         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3295                 ret = sbi->s_stripe;
3296         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3297                 ret = stripe_width;
3298         else if (stride && stride <= sbi->s_blocks_per_group)
3299                 ret = stride;
3300         else
3301                 ret = 0;
3302
3303         /*
3304          * If the stripe width is 1, this makes no sense and
3305          * we set it to 0 to turn off stripe handling code.
3306          */
3307         if (ret <= 1)
3308                 ret = 0;
3309
3310         return ret;
3311 }
3312
3313 /*
3314  * Check whether this filesystem can be mounted based on
3315  * the features present and the RDONLY/RDWR mount requested.
3316  * Returns 1 if this filesystem can be mounted as requested,
3317  * 0 if it cannot be.
3318  */
3319 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
3320 {
3321         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3322                 ext4_msg(sb, KERN_ERR,
3323                         "Couldn't mount because of "
3324                         "unsupported optional features (%x)",
3325                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3326                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3327                 return 0;
3328         }
3329
3330 #ifndef CONFIG_UNICODE
3331         if (ext4_has_feature_casefold(sb)) {
3332                 ext4_msg(sb, KERN_ERR,
3333                          "Filesystem with casefold feature cannot be "
3334                          "mounted without CONFIG_UNICODE");
3335                 return 0;
3336         }
3337 #endif
3338
3339         if (readonly)
3340                 return 1;
3341
3342         if (ext4_has_feature_readonly(sb)) {
3343                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3344                 sb->s_flags |= SB_RDONLY;
3345                 return 1;
3346         }
3347
3348         /* Check that feature set is OK for a read-write mount */
3349         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3350                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3351                          "unsupported optional features (%x)",
3352                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3353                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3354                 return 0;
3355         }
3356         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3357                 ext4_msg(sb, KERN_ERR,
3358                          "Can't support bigalloc feature without "
3359                          "extents feature\n");
3360                 return 0;
3361         }
3362
3363 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3364         if (!readonly && (ext4_has_feature_quota(sb) ||
3365                           ext4_has_feature_project(sb))) {
3366                 ext4_msg(sb, KERN_ERR,
3367                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3368                 return 0;
3369         }
3370 #endif  /* CONFIG_QUOTA */
3371         return 1;
3372 }
3373
3374 /*
3375  * This function is called once a day if we have errors logged
3376  * on the file system
3377  */
3378 static void print_daily_error_info(struct timer_list *t)
3379 {
3380         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3381         struct super_block *sb = sbi->s_sb;
3382         struct ext4_super_block *es = sbi->s_es;
3383
3384         if (es->s_error_count)
3385                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3386                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3387                          le32_to_cpu(es->s_error_count));
3388         if (es->s_first_error_time) {
3389                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3390                        sb->s_id,
3391                        ext4_get_tstamp(es, s_first_error_time),
3392                        (int) sizeof(es->s_first_error_func),
3393                        es->s_first_error_func,
3394                        le32_to_cpu(es->s_first_error_line));
3395                 if (es->s_first_error_ino)
3396                         printk(KERN_CONT ": inode %u",
3397                                le32_to_cpu(es->s_first_error_ino));
3398                 if (es->s_first_error_block)
3399                         printk(KERN_CONT ": block %llu", (unsigned long long)
3400                                le64_to_cpu(es->s_first_error_block));
3401                 printk(KERN_CONT "\n");
3402         }
3403         if (es->s_last_error_time) {
3404                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3405                        sb->s_id,
3406                        ext4_get_tstamp(es, s_last_error_time),
3407                        (int) sizeof(es->s_last_error_func),
3408                        es->s_last_error_func,
3409                        le32_to_cpu(es->s_last_error_line));
3410                 if (es->s_last_error_ino)
3411                         printk(KERN_CONT ": inode %u",
3412                                le32_to_cpu(es->s_last_error_ino));
3413                 if (es->s_last_error_block)
3414                         printk(KERN_CONT ": block %llu", (unsigned long long)
3415                                le64_to_cpu(es->s_last_error_block));
3416                 printk(KERN_CONT "\n");
3417         }
3418         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3419 }
3420
3421 /* Find next suitable group and run ext4_init_inode_table */
3422 static int ext4_run_li_request(struct ext4_li_request *elr)
3423 {
3424         struct ext4_group_desc *gdp = NULL;
3425         struct super_block *sb = elr->lr_super;
3426         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3427         ext4_group_t group = elr->lr_next_group;
3428         unsigned long timeout = 0;
3429         unsigned int prefetch_ios = 0;
3430         int ret = 0;
3431
3432         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3433                 elr->lr_next_group = ext4_mb_prefetch(sb, group,
3434                                 EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3435                 if (prefetch_ios)
3436                         ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3437                                               prefetch_ios);
3438                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3439                                             prefetch_ios);
3440                 if (group >= elr->lr_next_group) {
3441                         ret = 1;
3442                         if (elr->lr_first_not_zeroed != ngroups &&
3443                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3444                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3445                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3446                                 ret = 0;
3447                         }
3448                 }
3449                 return ret;
3450         }
3451
3452         for (; group < ngroups; group++) {
3453                 gdp = ext4_get_group_desc(sb, group, NULL);
3454                 if (!gdp) {
3455                         ret = 1;
3456                         break;
3457                 }
3458
3459                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3460                         break;
3461         }
3462
3463         if (group >= ngroups)
3464                 ret = 1;
3465
3466         if (!ret) {
3467                 timeout = jiffies;
3468                 ret = ext4_init_inode_table(sb, group,
3469                                             elr->lr_timeout ? 0 : 1);
3470                 trace_ext4_lazy_itable_init(sb, group);
3471                 if (elr->lr_timeout == 0) {
3472                         timeout = (jiffies - timeout) *
3473                                 EXT4_SB(elr->lr_super)->s_li_wait_mult;
3474                         elr->lr_timeout = timeout;
3475                 }
3476                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3477                 elr->lr_next_group = group + 1;
3478         }
3479         return ret;
3480 }
3481
3482 /*
3483  * Remove lr_request from the list_request and free the
3484  * request structure. Should be called with li_list_mtx held
3485  */
3486 static void ext4_remove_li_request(struct ext4_li_request *elr)
3487 {
3488         if (!elr)
3489                 return;
3490
3491         list_del(&elr->lr_request);
3492         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3493         kfree(elr);
3494 }
3495
3496 static void ext4_unregister_li_request(struct super_block *sb)
3497 {
3498         mutex_lock(&ext4_li_mtx);
3499         if (!ext4_li_info) {
3500                 mutex_unlock(&ext4_li_mtx);
3501                 return;
3502         }
3503
3504         mutex_lock(&ext4_li_info->li_list_mtx);
3505         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3506         mutex_unlock(&ext4_li_info->li_list_mtx);
3507         mutex_unlock(&ext4_li_mtx);
3508 }
3509
3510 static struct task_struct *ext4_lazyinit_task;
3511
3512 /*
3513  * This is the function where ext4lazyinit thread lives. It walks
3514  * through the request list searching for next scheduled filesystem.
3515  * When such a fs is found, run the lazy initialization request
3516  * (ext4_rn_li_request) and keep track of the time spend in this
3517  * function. Based on that time we compute next schedule time of
3518  * the request. When walking through the list is complete, compute
3519  * next waking time and put itself into sleep.
3520  */
3521 static int ext4_lazyinit_thread(void *arg)
3522 {
3523         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3524         struct list_head *pos, *n;
3525         struct ext4_li_request *elr;
3526         unsigned long next_wakeup, cur;
3527
3528         BUG_ON(NULL == eli);
3529
3530 cont_thread:
3531         while (true) {
3532                 next_wakeup = MAX_JIFFY_OFFSET;
3533
3534                 mutex_lock(&eli->li_list_mtx);
3535                 if (list_empty(&eli->li_request_list)) {
3536                         mutex_unlock(&eli->li_list_mtx);
3537                         goto exit_thread;
3538                 }
3539                 list_for_each_safe(pos, n, &eli->li_request_list) {
3540                         int err = 0;
3541                         int progress = 0;
3542                         elr = list_entry(pos, struct ext4_li_request,
3543                                          lr_request);
3544
3545                         if (time_before(jiffies, elr->lr_next_sched)) {
3546                                 if (time_before(elr->lr_next_sched, next_wakeup))
3547                                         next_wakeup = elr->lr_next_sched;
3548                                 continue;
3549                         }
3550                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3551                                 if (sb_start_write_trylock(elr->lr_super)) {
3552                                         progress = 1;
3553                                         /*
3554                                          * We hold sb->s_umount, sb can not
3555                                          * be removed from the list, it is
3556                                          * now safe to drop li_list_mtx
3557                                          */
3558                                         mutex_unlock(&eli->li_list_mtx);
3559                                         err = ext4_run_li_request(elr);
3560                                         sb_end_write(elr->lr_super);
3561                                         mutex_lock(&eli->li_list_mtx);
3562                                         n = pos->next;
3563                                 }
3564                                 up_read((&elr->lr_super->s_umount));
3565                         }
3566                         /* error, remove the lazy_init job */
3567                         if (err) {
3568                                 ext4_remove_li_request(elr);
3569                                 continue;
3570                         }
3571                         if (!progress) {
3572                                 elr->lr_next_sched = jiffies +
3573                                         (prandom_u32()
3574                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3575                         }
3576                         if (time_before(elr->lr_next_sched, next_wakeup))
3577                                 next_wakeup = elr->lr_next_sched;
3578                 }
3579                 mutex_unlock(&eli->li_list_mtx);
3580
3581                 try_to_freeze();
3582
3583                 cur = jiffies;
3584                 if ((time_after_eq(cur, next_wakeup)) ||
3585                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3586                         cond_resched();
3587                         continue;
3588                 }
3589
3590                 schedule_timeout_interruptible(next_wakeup - cur);
3591
3592                 if (kthread_should_stop()) {
3593                         ext4_clear_request_list();
3594                         goto exit_thread;
3595                 }
3596         }
3597
3598 exit_thread:
3599         /*
3600          * It looks like the request list is empty, but we need
3601          * to check it under the li_list_mtx lock, to prevent any
3602          * additions into it, and of course we should lock ext4_li_mtx
3603          * to atomically free the list and ext4_li_info, because at
3604          * this point another ext4 filesystem could be registering
3605          * new one.
3606          */
3607         mutex_lock(&ext4_li_mtx);
3608         mutex_lock(&eli->li_list_mtx);
3609         if (!list_empty(&eli->li_request_list)) {
3610                 mutex_unlock(&eli->li_list_mtx);
3611                 mutex_unlock(&ext4_li_mtx);
3612                 goto cont_thread;
3613         }
3614         mutex_unlock(&eli->li_list_mtx);
3615         kfree(ext4_li_info);
3616         ext4_li_info = NULL;
3617         mutex_unlock(&ext4_li_mtx);
3618
3619         return 0;
3620 }
3621
3622 static void ext4_clear_request_list(void)
3623 {
3624         struct list_head *pos, *n;
3625         struct ext4_li_request *elr;
3626
3627         mutex_lock(&ext4_li_info->li_list_mtx);
3628         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3629                 elr = list_entry(pos, struct ext4_li_request,
3630                                  lr_request);
3631                 ext4_remove_li_request(elr);
3632         }
3633         mutex_unlock(&ext4_li_info->li_list_mtx);
3634 }
3635
3636 static int ext4_run_lazyinit_thread(void)
3637 {
3638         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3639                                          ext4_li_info, "ext4lazyinit");
3640         if (IS_ERR(ext4_lazyinit_task)) {
3641                 int err = PTR_ERR(ext4_lazyinit_task);
3642                 ext4_clear_request_list();
3643                 kfree(ext4_li_info);
3644                 ext4_li_info = NULL;
3645                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3646                                  "initialization thread\n",
3647                                  err);
3648                 return err;
3649         }
3650         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3651         return 0;
3652 }
3653
3654 /*
3655  * Check whether it make sense to run itable init. thread or not.
3656  * If there is at least one uninitialized inode table, return
3657  * corresponding group number, else the loop goes through all
3658  * groups and return total number of groups.
3659  */
3660 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3661 {
3662         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3663         struct ext4_group_desc *gdp = NULL;
3664
3665         if (!ext4_has_group_desc_csum(sb))
3666                 return ngroups;
3667
3668         for (group = 0; group < ngroups; group++) {
3669                 gdp = ext4_get_group_desc(sb, group, NULL);
3670                 if (!gdp)
3671                         continue;
3672
3673                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3674                         break;
3675         }
3676
3677         return group;
3678 }
3679
3680 static int ext4_li_info_new(void)
3681 {
3682         struct ext4_lazy_init *eli = NULL;
3683
3684         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3685         if (!eli)
3686                 return -ENOMEM;
3687
3688         INIT_LIST_HEAD(&eli->li_request_list);
3689         mutex_init(&eli->li_list_mtx);
3690
3691         eli->li_state |= EXT4_LAZYINIT_QUIT;
3692
3693         ext4_li_info = eli;
3694
3695         return 0;
3696 }
3697
3698 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3699                                             ext4_group_t start)
3700 {
3701         struct ext4_li_request *elr;
3702
3703         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3704         if (!elr)
3705                 return NULL;
3706
3707         elr->lr_super = sb;
3708         elr->lr_first_not_zeroed = start;
3709         if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS)) {
3710                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3711                 elr->lr_next_group = start;
3712         } else {
3713                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3714         }
3715
3716         /*
3717          * Randomize first schedule time of the request to
3718          * spread the inode table initialization requests
3719          * better.
3720          */
3721         elr->lr_next_sched = jiffies + (prandom_u32() %
3722                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3723         return elr;
3724 }
3725
3726 int ext4_register_li_request(struct super_block *sb,
3727                              ext4_group_t first_not_zeroed)
3728 {
3729         struct ext4_sb_info *sbi = EXT4_SB(sb);
3730         struct ext4_li_request *elr = NULL;
3731         ext4_group_t ngroups = sbi->s_groups_count;
3732         int ret = 0;
3733
3734         mutex_lock(&ext4_li_mtx);
3735         if (sbi->s_li_request != NULL) {
3736                 /*
3737                  * Reset timeout so it can be computed again, because
3738                  * s_li_wait_mult might have changed.
3739                  */
3740                 sbi->s_li_request->lr_timeout = 0;
3741                 goto out;
3742         }
3743
3744         if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS) &&
3745             (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3746              !test_opt(sb, INIT_INODE_TABLE)))
3747                 goto out;
3748
3749         elr = ext4_li_request_new(sb, first_not_zeroed);
3750         if (!elr) {
3751                 ret = -ENOMEM;
3752                 goto out;
3753         }
3754
3755         if (NULL == ext4_li_info) {
3756                 ret = ext4_li_info_new();
3757                 if (ret)
3758                         goto out;
3759         }
3760
3761         mutex_lock(&ext4_li_info->li_list_mtx);
3762         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3763         mutex_unlock(&ext4_li_info->li_list_mtx);
3764
3765         sbi->s_li_request = elr;
3766         /*
3767          * set elr to NULL here since it has been inserted to
3768          * the request_list and the removal and free of it is
3769          * handled by ext4_clear_request_list from now on.
3770          */
3771         elr = NULL;
3772
3773         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3774                 ret = ext4_run_lazyinit_thread();
3775                 if (ret)
3776                         goto out;
3777         }
3778 out:
3779         mutex_unlock(&ext4_li_mtx);
3780         if (ret)
3781                 kfree(elr);
3782         return ret;
3783 }
3784
3785 /*
3786  * We do not need to lock anything since this is called on
3787  * module unload.
3788  */
3789 static void ext4_destroy_lazyinit_thread(void)
3790 {
3791         /*
3792          * If thread exited earlier
3793          * there's nothing to be done.
3794          */
3795         if (!ext4_li_info || !ext4_lazyinit_task)
3796                 return;
3797
3798         kthread_stop(ext4_lazyinit_task);
3799 }
3800
3801 static int set_journal_csum_feature_set(struct super_block *sb)
3802 {
3803         int ret = 1;
3804         int compat, incompat;
3805         struct ext4_sb_info *sbi = EXT4_SB(sb);
3806
3807         if (ext4_has_metadata_csum(sb)) {
3808                 /* journal checksum v3 */
3809                 compat = 0;
3810                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3811         } else {
3812                 /* journal checksum v1 */
3813                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3814                 incompat = 0;
3815         }
3816
3817         jbd2_journal_clear_features(sbi->s_journal,
3818                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3819                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3820                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3821         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3822                 ret = jbd2_journal_set_features(sbi->s_journal,
3823                                 compat, 0,
3824                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3825                                 incompat);
3826         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3827                 ret = jbd2_journal_set_features(sbi->s_journal,
3828                                 compat, 0,
3829                                 incompat);
3830                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3831                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3832         } else {
3833                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3834                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3835         }
3836
3837         return ret;
3838 }
3839
3840 /*
3841  * Note: calculating the overhead so we can be compatible with
3842  * historical BSD practice is quite difficult in the face of
3843  * clusters/bigalloc.  This is because multiple metadata blocks from
3844  * different block group can end up in the same allocation cluster.
3845  * Calculating the exact overhead in the face of clustered allocation
3846  * requires either O(all block bitmaps) in memory or O(number of block
3847  * groups**2) in time.  We will still calculate the superblock for
3848  * older file systems --- and if we come across with a bigalloc file
3849  * system with zero in s_overhead_clusters the estimate will be close to
3850  * correct especially for very large cluster sizes --- but for newer
3851  * file systems, it's better to calculate this figure once at mkfs
3852  * time, and store it in the superblock.  If the superblock value is
3853  * present (even for non-bigalloc file systems), we will use it.
3854  */
3855 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3856                           char *buf)
3857 {
3858         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3859         struct ext4_group_desc  *gdp;
3860         ext4_fsblk_t            first_block, last_block, b;
3861         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3862         int                     s, j, count = 0;
3863
3864         if (!ext4_has_feature_bigalloc(sb))
3865                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3866                         sbi->s_itb_per_group + 2);
3867
3868         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3869                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3870         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3871         for (i = 0; i < ngroups; i++) {
3872                 gdp = ext4_get_group_desc(sb, i, NULL);
3873                 b = ext4_block_bitmap(sb, gdp);
3874                 if (b >= first_block && b <= last_block) {
3875                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3876                         count++;
3877                 }
3878                 b = ext4_inode_bitmap(sb, gdp);
3879                 if (b >= first_block && b <= last_block) {
3880                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3881                         count++;
3882                 }
3883                 b = ext4_inode_table(sb, gdp);
3884                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3885                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3886                                 int c = EXT4_B2C(sbi, b - first_block);
3887                                 ext4_set_bit(c, buf);
3888                                 count++;
3889                         }
3890                 if (i != grp)
3891                         continue;
3892                 s = 0;
3893                 if (ext4_bg_has_super(sb, grp)) {
3894                         ext4_set_bit(s++, buf);
3895                         count++;
3896                 }
3897                 j = ext4_bg_num_gdb(sb, grp);
3898                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3899                         ext4_error(sb, "Invalid number of block group "
3900                                    "descriptor blocks: %d", j);
3901                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3902                 }
3903                 count += j;
3904                 for (; j > 0; j--)
3905                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3906         }
3907         if (!count)
3908                 return 0;
3909         return EXT4_CLUSTERS_PER_GROUP(sb) -
3910                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3911 }
3912
3913 /*
3914  * Compute the overhead and stash it in sbi->s_overhead
3915  */
3916 int ext4_calculate_overhead(struct super_block *sb)
3917 {
3918         struct ext4_sb_info *sbi = EXT4_SB(sb);
3919         struct ext4_super_block *es = sbi->s_es;
3920         struct inode *j_inode;
3921         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3922         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3923         ext4_fsblk_t overhead = 0;
3924         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3925
3926         if (!buf)
3927                 return -ENOMEM;
3928
3929         /*
3930          * Compute the overhead (FS structures).  This is constant
3931          * for a given filesystem unless the number of block groups
3932          * changes so we cache the previous value until it does.
3933          */
3934
3935         /*
3936          * All of the blocks before first_data_block are overhead
3937          */
3938         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3939
3940         /*
3941          * Add the overhead found in each block group
3942          */
3943         for (i = 0; i < ngroups; i++) {
3944                 int blks;
3945
3946                 blks = count_overhead(sb, i, buf);
3947                 overhead += blks;
3948                 if (blks)
3949                         memset(buf, 0, PAGE_SIZE);
3950                 cond_resched();
3951         }
3952
3953         /*
3954          * Add the internal journal blocks whether the journal has been
3955          * loaded or not
3956          */
3957         if (sbi->s_journal && !sbi->s_journal_bdev)
3958                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
3959         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3960                 /* j_inum for internal journal is non-zero */
3961                 j_inode = ext4_get_journal_inode(sb, j_inum);
3962                 if (j_inode) {
3963                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3964                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3965                         iput(j_inode);
3966                 } else {
3967                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3968                 }
3969         }
3970         sbi->s_overhead = overhead;
3971         smp_wmb();
3972         free_page((unsigned long) buf);
3973         return 0;
3974 }
3975
3976 static void ext4_set_resv_clusters(struct super_block *sb)
3977 {
3978         ext4_fsblk_t resv_clusters;
3979         struct ext4_sb_info *sbi = EXT4_SB(sb);
3980
3981         /*
3982          * There's no need to reserve anything when we aren't using extents.
3983          * The space estimates are exact, there are no unwritten extents,
3984          * hole punching doesn't need new metadata... This is needed especially
3985          * to keep ext2/3 backward compatibility.
3986          */
3987         if (!ext4_has_feature_extents(sb))
3988                 return;
3989         /*
3990          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3991          * This should cover the situations where we can not afford to run
3992          * out of space like for example punch hole, or converting
3993          * unwritten extents in delalloc path. In most cases such
3994          * allocation would require 1, or 2 blocks, higher numbers are
3995          * very rare.
3996          */
3997         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3998                          sbi->s_cluster_bits);
3999
4000         do_div(resv_clusters, 50);
4001         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4002
4003         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4004 }
4005
4006 static const char *ext4_quota_mode(struct super_block *sb)
4007 {
4008 #ifdef CONFIG_QUOTA
4009         if (!ext4_quota_capable(sb))
4010                 return "none";
4011
4012         if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
4013                 return "journalled";
4014         else
4015                 return "writeback";
4016 #else
4017         return "disabled";
4018 #endif
4019 }
4020
4021 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
4022 {
4023         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
4024         char *orig_data = kstrdup(data, GFP_KERNEL);
4025         struct buffer_head *bh, **group_desc;
4026         struct ext4_super_block *es = NULL;
4027         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4028         struct flex_groups **flex_groups;
4029         ext4_fsblk_t block;
4030         ext4_fsblk_t sb_block = get_sb_block(&data);
4031         ext4_fsblk_t logical_sb_block;
4032         unsigned long offset = 0;
4033         unsigned long def_mount_opts;
4034         struct inode *root;
4035         const char *descr;
4036         int ret = -ENOMEM;
4037         int blocksize, clustersize;
4038         unsigned int db_count;
4039         unsigned int i;
4040         int needs_recovery, has_huge_files;
4041         __u64 blocks_count;
4042         int err = 0;
4043         ext4_group_t first_not_zeroed;
4044         struct ext4_parsed_options parsed_opts;
4045
4046         /* Set defaults for the variables that will be set during parsing */
4047         parsed_opts.journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4048         parsed_opts.journal_devnum = 0;
4049         parsed_opts.mb_optimize_scan = DEFAULT_MB_OPTIMIZE_SCAN;
4050
4051         if ((data && !orig_data) || !sbi)
4052                 goto out_free_base;
4053
4054         sbi->s_daxdev = dax_dev;
4055         sbi->s_blockgroup_lock =
4056                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4057         if (!sbi->s_blockgroup_lock)
4058                 goto out_free_base;
4059
4060         sb->s_fs_info = sbi;
4061         sbi->s_sb = sb;
4062         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
4063         sbi->s_sb_block = sb_block;
4064         sbi->s_sectors_written_start =
4065                 part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
4066
4067         /* Cleanup superblock name */
4068         strreplace(sb->s_id, '/', '!');
4069
4070         /* -EINVAL is default */
4071         ret = -EINVAL;
4072         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
4073         if (!blocksize) {
4074                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
4075                 goto out_fail;
4076         }
4077
4078         /*
4079          * The ext4 superblock will not be buffer aligned for other than 1kB
4080          * block sizes.  We need to calculate the offset from buffer start.
4081          */
4082         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
4083                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4084                 offset = do_div(logical_sb_block, blocksize);
4085         } else {
4086                 logical_sb_block = sb_block;
4087         }
4088
4089         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4090         if (IS_ERR(bh)) {
4091                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
4092                 ret = PTR_ERR(bh);
4093                 goto out_fail;
4094         }
4095         /*
4096          * Note: s_es must be initialized as soon as possible because
4097          *       some ext4 macro-instructions depend on its value
4098          */
4099         es = (struct ext4_super_block *) (bh->b_data + offset);
4100         sbi->s_es = es;
4101         sb->s_magic = le16_to_cpu(es->s_magic);
4102         if (sb->s_magic != EXT4_SUPER_MAGIC)
4103                 goto cantfind_ext4;
4104         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
4105
4106         /* Warn if metadata_csum and gdt_csum are both set. */
4107         if (ext4_has_feature_metadata_csum(sb) &&
4108             ext4_has_feature_gdt_csum(sb))
4109                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4110                              "redundant flags; please run fsck.");
4111
4112         /* Check for a known checksum algorithm */
4113         if (!ext4_verify_csum_type(sb, es)) {
4114                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4115                          "unknown checksum algorithm.");
4116                 silent = 1;
4117                 goto cantfind_ext4;
4118         }
4119
4120         /* Load the checksum driver */
4121         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4122         if (IS_ERR(sbi->s_chksum_driver)) {
4123                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4124                 ret = PTR_ERR(sbi->s_chksum_driver);
4125                 sbi->s_chksum_driver = NULL;
4126                 goto failed_mount;
4127         }
4128
4129         /* Check superblock checksum */
4130         if (!ext4_superblock_csum_verify(sb, es)) {
4131                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4132                          "invalid superblock checksum.  Run e2fsck?");
4133                 silent = 1;
4134                 ret = -EFSBADCRC;
4135                 goto cantfind_ext4;
4136         }
4137
4138         /* Precompute checksum seed for all metadata */
4139         if (ext4_has_feature_csum_seed(sb))
4140                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4141         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4142                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4143                                                sizeof(es->s_uuid));
4144
4145         /* Set defaults before we parse the mount options */
4146         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4147         set_opt(sb, INIT_INODE_TABLE);
4148         if (def_mount_opts & EXT4_DEFM_DEBUG)
4149                 set_opt(sb, DEBUG);
4150         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4151                 set_opt(sb, GRPID);
4152         if (def_mount_opts & EXT4_DEFM_UID16)
4153                 set_opt(sb, NO_UID32);
4154         /* xattr user namespace & acls are now defaulted on */
4155         set_opt(sb, XATTR_USER);
4156 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4157         set_opt(sb, POSIX_ACL);
4158 #endif
4159         if (ext4_has_feature_fast_commit(sb))
4160                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4161         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4162         if (ext4_has_metadata_csum(sb))
4163                 set_opt(sb, JOURNAL_CHECKSUM);
4164
4165         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4166                 set_opt(sb, JOURNAL_DATA);
4167         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4168                 set_opt(sb, ORDERED_DATA);
4169         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4170                 set_opt(sb, WRITEBACK_DATA);
4171
4172         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
4173                 set_opt(sb, ERRORS_PANIC);
4174         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
4175                 set_opt(sb, ERRORS_CONT);
4176         else
4177                 set_opt(sb, ERRORS_RO);
4178         /* block_validity enabled by default; disable with noblock_validity */
4179         set_opt(sb, BLOCK_VALIDITY);
4180         if (def_mount_opts & EXT4_DEFM_DISCARD)
4181                 set_opt(sb, DISCARD);
4182
4183         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
4184         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
4185         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
4186         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
4187         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
4188
4189         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4190                 set_opt(sb, BARRIER);
4191
4192         /*
4193          * enable delayed allocation by default
4194          * Use -o nodelalloc to turn it off
4195          */
4196         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4197             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4198                 set_opt(sb, DELALLOC);
4199
4200         /*
4201          * set default s_li_wait_mult for lazyinit, for the case there is
4202          * no mount option specified.
4203          */
4204         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
4205
4206         if (le32_to_cpu(es->s_log_block_size) >
4207             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4208                 ext4_msg(sb, KERN_ERR,
4209                          "Invalid log block size: %u",
4210                          le32_to_cpu(es->s_log_block_size));
4211                 goto failed_mount;
4212         }
4213         if (le32_to_cpu(es->s_log_cluster_size) >
4214             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4215                 ext4_msg(sb, KERN_ERR,
4216                          "Invalid log cluster size: %u",
4217                          le32_to_cpu(es->s_log_cluster_size));
4218                 goto failed_mount;
4219         }
4220
4221         blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
4222
4223         if (blocksize == PAGE_SIZE)
4224                 set_opt(sb, DIOREAD_NOLOCK);
4225
4226         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4227                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4228                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4229         } else {
4230                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4231                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4232                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4233                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4234                                  sbi->s_first_ino);
4235                         goto failed_mount;
4236                 }
4237                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4238                     (!is_power_of_2(sbi->s_inode_size)) ||
4239                     (sbi->s_inode_size > blocksize)) {
4240                         ext4_msg(sb, KERN_ERR,
4241                                "unsupported inode size: %d",
4242                                sbi->s_inode_size);
4243                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
4244                         goto failed_mount;
4245                 }
4246                 /*
4247                  * i_atime_extra is the last extra field available for
4248                  * [acm]times in struct ext4_inode. Checking for that
4249                  * field should suffice to ensure we have extra space
4250                  * for all three.
4251                  */
4252                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4253                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4254                         sb->s_time_gran = 1;
4255                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4256                 } else {
4257                         sb->s_time_gran = NSEC_PER_SEC;
4258                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4259                 }
4260                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4261         }
4262         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4263                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4264                         EXT4_GOOD_OLD_INODE_SIZE;
4265                 if (ext4_has_feature_extra_isize(sb)) {
4266                         unsigned v, max = (sbi->s_inode_size -
4267                                            EXT4_GOOD_OLD_INODE_SIZE);
4268
4269                         v = le16_to_cpu(es->s_want_extra_isize);
4270                         if (v > max) {
4271                                 ext4_msg(sb, KERN_ERR,
4272                                          "bad s_want_extra_isize: %d", v);
4273                                 goto failed_mount;
4274                         }
4275                         if (sbi->s_want_extra_isize < v)
4276                                 sbi->s_want_extra_isize = v;
4277
4278                         v = le16_to_cpu(es->s_min_extra_isize);
4279                         if (v > max) {
4280                                 ext4_msg(sb, KERN_ERR,
4281                                          "bad s_min_extra_isize: %d", v);
4282                                 goto failed_mount;
4283                         }
4284                         if (sbi->s_want_extra_isize < v)
4285                                 sbi->s_want_extra_isize = v;
4286                 }
4287         }
4288
4289         if (sbi->s_es->s_mount_opts[0]) {
4290                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
4291                                               sizeof(sbi->s_es->s_mount_opts),
4292                                               GFP_KERNEL);
4293                 if (!s_mount_opts)
4294                         goto failed_mount;
4295                 if (!parse_options(s_mount_opts, sb, &parsed_opts, 0)) {
4296                         ext4_msg(sb, KERN_WARNING,
4297                                  "failed to parse options in superblock: %s",
4298                                  s_mount_opts);
4299                 }
4300                 kfree(s_mount_opts);
4301         }
4302         sbi->s_def_mount_opt = sbi->s_mount_opt;
4303         if (!parse_options((char *) data, sb, &parsed_opts, 0))
4304                 goto failed_mount;
4305
4306 #ifdef CONFIG_UNICODE
4307         if (ext4_has_feature_casefold(sb) && !sb->s_encoding) {
4308                 const struct ext4_sb_encodings *encoding_info;
4309                 struct unicode_map *encoding;
4310                 __u16 encoding_flags;
4311
4312                 if (ext4_sb_read_encoding(es, &encoding_info,
4313                                           &encoding_flags)) {
4314                         ext4_msg(sb, KERN_ERR,
4315                                  "Encoding requested by superblock is unknown");
4316                         goto failed_mount;
4317                 }
4318
4319                 encoding = utf8_load(encoding_info->version);
4320                 if (IS_ERR(encoding)) {
4321                         ext4_msg(sb, KERN_ERR,
4322                                  "can't mount with superblock charset: %s-%s "
4323                                  "not supported by the kernel. flags: 0x%x.",
4324                                  encoding_info->name, encoding_info->version,
4325                                  encoding_flags);
4326                         goto failed_mount;
4327                 }
4328                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4329                          "%s-%s with flags 0x%hx", encoding_info->name,
4330                          encoding_info->version?:"\b", encoding_flags);
4331
4332                 sb->s_encoding = encoding;
4333                 sb->s_encoding_flags = encoding_flags;
4334         }
4335 #endif
4336
4337         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4338                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, O_DIRECT and fast_commit support!\n");
4339                 /* can't mount with both data=journal and dioread_nolock. */
4340                 clear_opt(sb, DIOREAD_NOLOCK);
4341                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4342                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4343                         ext4_msg(sb, KERN_ERR, "can't mount with "
4344                                  "both data=journal and delalloc");
4345                         goto failed_mount;
4346                 }
4347                 if (test_opt(sb, DAX_ALWAYS)) {
4348                         ext4_msg(sb, KERN_ERR, "can't mount with "
4349                                  "both data=journal and dax");
4350                         goto failed_mount;
4351                 }
4352                 if (ext4_has_feature_encrypt(sb)) {
4353                         ext4_msg(sb, KERN_WARNING,
4354                                  "encrypted files will use data=ordered "
4355                                  "instead of data journaling mode");
4356                 }
4357                 if (test_opt(sb, DELALLOC))
4358                         clear_opt(sb, DELALLOC);
4359         } else {
4360                 sb->s_iflags |= SB_I_CGROUPWB;
4361         }
4362
4363         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4364                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4365
4366         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4367             (ext4_has_compat_features(sb) ||
4368              ext4_has_ro_compat_features(sb) ||
4369              ext4_has_incompat_features(sb)))
4370                 ext4_msg(sb, KERN_WARNING,
4371                        "feature flags set on rev 0 fs, "
4372                        "running e2fsck is recommended");
4373
4374         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4375                 set_opt2(sb, HURD_COMPAT);
4376                 if (ext4_has_feature_64bit(sb)) {
4377                         ext4_msg(sb, KERN_ERR,
4378                                  "The Hurd can't support 64-bit file systems");
4379                         goto failed_mount;
4380                 }
4381
4382                 /*
4383                  * ea_inode feature uses l_i_version field which is not
4384                  * available in HURD_COMPAT mode.
4385                  */
4386                 if (ext4_has_feature_ea_inode(sb)) {
4387                         ext4_msg(sb, KERN_ERR,
4388                                  "ea_inode feature is not supported for Hurd");
4389                         goto failed_mount;
4390                 }
4391         }
4392
4393         if (IS_EXT2_SB(sb)) {
4394                 if (ext2_feature_set_ok(sb))
4395                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4396                                  "using the ext4 subsystem");
4397                 else {
4398                         /*
4399                          * If we're probing be silent, if this looks like
4400                          * it's actually an ext[34] filesystem.
4401                          */
4402                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4403                                 goto failed_mount;
4404                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4405                                  "to feature incompatibilities");
4406                         goto failed_mount;
4407                 }
4408         }
4409
4410         if (IS_EXT3_SB(sb)) {
4411                 if (ext3_feature_set_ok(sb))
4412                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4413                                  "using the ext4 subsystem");
4414                 else {
4415                         /*
4416                          * If we're probing be silent, if this looks like
4417                          * it's actually an ext4 filesystem.
4418                          */
4419                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4420                                 goto failed_mount;
4421                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4422                                  "to feature incompatibilities");
4423                         goto failed_mount;
4424                 }
4425         }
4426
4427         /*
4428          * Check feature flags regardless of the revision level, since we
4429          * previously didn't change the revision level when setting the flags,
4430          * so there is a chance incompat flags are set on a rev 0 filesystem.
4431          */
4432         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4433                 goto failed_mount;
4434
4435         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4436                 ext4_msg(sb, KERN_ERR,
4437                          "Number of reserved GDT blocks insanely large: %d",
4438                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4439                 goto failed_mount;
4440         }
4441
4442         if (bdev_dax_supported(sb->s_bdev, blocksize))
4443                 set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4444
4445         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4446                 if (ext4_has_feature_inline_data(sb)) {
4447                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4448                                         " that may contain inline data");
4449                         goto failed_mount;
4450                 }
4451                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4452                         ext4_msg(sb, KERN_ERR,
4453                                 "DAX unsupported by block device.");
4454                         goto failed_mount;
4455                 }
4456         }
4457
4458         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4459                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4460                          es->s_encryption_level);
4461                 goto failed_mount;
4462         }
4463
4464         if (sb->s_blocksize != blocksize) {
4465                 /*
4466                  * bh must be released before kill_bdev(), otherwise
4467                  * it won't be freed and its page also. kill_bdev()
4468                  * is called by sb_set_blocksize().
4469                  */
4470                 brelse(bh);
4471                 /* Validate the filesystem blocksize */
4472                 if (!sb_set_blocksize(sb, blocksize)) {
4473                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4474                                         blocksize);
4475                         bh = NULL;
4476                         goto failed_mount;
4477                 }
4478
4479                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4480                 offset = do_div(logical_sb_block, blocksize);
4481                 bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4482                 if (IS_ERR(bh)) {
4483                         ext4_msg(sb, KERN_ERR,
4484                                "Can't read superblock on 2nd try");
4485                         ret = PTR_ERR(bh);
4486                         bh = NULL;
4487                         goto failed_mount;
4488                 }
4489                 es = (struct ext4_super_block *)(bh->b_data + offset);
4490                 sbi->s_es = es;
4491                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4492                         ext4_msg(sb, KERN_ERR,
4493                                "Magic mismatch, very weird!");
4494                         goto failed_mount;
4495                 }
4496         }
4497
4498         has_huge_files = ext4_has_feature_huge_file(sb);
4499         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4500                                                       has_huge_files);
4501         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4502
4503         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4504         if (ext4_has_feature_64bit(sb)) {
4505                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4506                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4507                     !is_power_of_2(sbi->s_desc_size)) {
4508                         ext4_msg(sb, KERN_ERR,
4509                                "unsupported descriptor size %lu",
4510                                sbi->s_desc_size);
4511                         goto failed_mount;
4512                 }
4513         } else
4514                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4515
4516         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4517         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4518
4519         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4520         if (sbi->s_inodes_per_block == 0)
4521                 goto cantfind_ext4;
4522         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4523             sbi->s_inodes_per_group > blocksize * 8) {
4524                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4525                          sbi->s_inodes_per_group);
4526                 goto failed_mount;
4527         }
4528         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4529                                         sbi->s_inodes_per_block;
4530         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4531         sbi->s_sbh = bh;
4532         sbi->s_mount_state = le16_to_cpu(es->s_state);
4533         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4534         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4535
4536         for (i = 0; i < 4; i++)
4537                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4538         sbi->s_def_hash_version = es->s_def_hash_version;
4539         if (ext4_has_feature_dir_index(sb)) {
4540                 i = le32_to_cpu(es->s_flags);
4541                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4542                         sbi->s_hash_unsigned = 3;
4543                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4544 #ifdef __CHAR_UNSIGNED__
4545                         if (!sb_rdonly(sb))
4546                                 es->s_flags |=
4547                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4548                         sbi->s_hash_unsigned = 3;
4549 #else
4550                         if (!sb_rdonly(sb))
4551                                 es->s_flags |=
4552                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4553 #endif
4554                 }
4555         }
4556
4557         /* Handle clustersize */
4558         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4559         if (ext4_has_feature_bigalloc(sb)) {
4560                 if (clustersize < blocksize) {
4561                         ext4_msg(sb, KERN_ERR,
4562                                  "cluster size (%d) smaller than "
4563                                  "block size (%d)", clustersize, blocksize);
4564                         goto failed_mount;
4565                 }
4566                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4567                         le32_to_cpu(es->s_log_block_size);
4568                 sbi->s_clusters_per_group =
4569                         le32_to_cpu(es->s_clusters_per_group);
4570                 if (sbi->s_clusters_per_group > blocksize * 8) {
4571                         ext4_msg(sb, KERN_ERR,
4572                                  "#clusters per group too big: %lu",
4573                                  sbi->s_clusters_per_group);
4574                         goto failed_mount;
4575                 }
4576                 if (sbi->s_blocks_per_group !=
4577                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4578                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4579                                  "clusters per group (%lu) inconsistent",
4580                                  sbi->s_blocks_per_group,
4581                                  sbi->s_clusters_per_group);
4582                         goto failed_mount;
4583                 }
4584         } else {
4585                 if (clustersize != blocksize) {
4586                         ext4_msg(sb, KERN_ERR,
4587                                  "fragment/cluster size (%d) != "
4588                                  "block size (%d)", clustersize, blocksize);
4589                         goto failed_mount;
4590                 }
4591                 if (sbi->s_blocks_per_group > blocksize * 8) {
4592                         ext4_msg(sb, KERN_ERR,
4593                                  "#blocks per group too big: %lu",
4594                                  sbi->s_blocks_per_group);
4595                         goto failed_mount;
4596                 }
4597                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4598                 sbi->s_cluster_bits = 0;
4599         }
4600         sbi->s_cluster_ratio = clustersize / blocksize;
4601
4602         /* Do we have standard group size of clustersize * 8 blocks ? */
4603         if (sbi->s_blocks_per_group == clustersize << 3)
4604                 set_opt2(sb, STD_GROUP_SIZE);
4605
4606         /*
4607          * Test whether we have more sectors than will fit in sector_t,
4608          * and whether the max offset is addressable by the page cache.
4609          */
4610         err = generic_check_addressable(sb->s_blocksize_bits,
4611                                         ext4_blocks_count(es));
4612         if (err) {
4613                 ext4_msg(sb, KERN_ERR, "filesystem"
4614                          " too large to mount safely on this system");
4615                 goto failed_mount;
4616         }
4617
4618         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4619                 goto cantfind_ext4;
4620
4621         /* check blocks count against device size */
4622         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4623         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4624                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4625                        "exceeds size of device (%llu blocks)",
4626                        ext4_blocks_count(es), blocks_count);
4627                 goto failed_mount;
4628         }
4629
4630         /*
4631          * It makes no sense for the first data block to be beyond the end
4632          * of the filesystem.
4633          */
4634         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4635                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4636                          "block %u is beyond end of filesystem (%llu)",
4637                          le32_to_cpu(es->s_first_data_block),
4638                          ext4_blocks_count(es));
4639                 goto failed_mount;
4640         }
4641         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4642             (sbi->s_cluster_ratio == 1)) {
4643                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4644                          "block is 0 with a 1k block and cluster size");
4645                 goto failed_mount;
4646         }
4647
4648         blocks_count = (ext4_blocks_count(es) -
4649                         le32_to_cpu(es->s_first_data_block) +
4650                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4651         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4652         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4653                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4654                        "(block count %llu, first data block %u, "
4655                        "blocks per group %lu)", blocks_count,
4656                        ext4_blocks_count(es),
4657                        le32_to_cpu(es->s_first_data_block),
4658                        EXT4_BLOCKS_PER_GROUP(sb));
4659                 goto failed_mount;
4660         }
4661         sbi->s_groups_count = blocks_count;
4662         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4663                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4664         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4665             le32_to_cpu(es->s_inodes_count)) {
4666                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4667                          le32_to_cpu(es->s_inodes_count),
4668                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4669                 ret = -EINVAL;
4670                 goto failed_mount;
4671         }
4672         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4673                    EXT4_DESC_PER_BLOCK(sb);
4674         if (ext4_has_feature_meta_bg(sb)) {
4675                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4676                         ext4_msg(sb, KERN_WARNING,
4677                                  "first meta block group too large: %u "
4678                                  "(group descriptor block count %u)",
4679                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4680                         goto failed_mount;
4681                 }
4682         }
4683         rcu_assign_pointer(sbi->s_group_desc,
4684                            kvmalloc_array(db_count,
4685                                           sizeof(struct buffer_head *),
4686                                           GFP_KERNEL));
4687         if (sbi->s_group_desc == NULL) {
4688                 ext4_msg(sb, KERN_ERR, "not enough memory");
4689                 ret = -ENOMEM;
4690                 goto failed_mount;
4691         }
4692
4693         bgl_lock_init(sbi->s_blockgroup_lock);
4694
4695         /* Pre-read the descriptors into the buffer cache */
4696         for (i = 0; i < db_count; i++) {
4697                 block = descriptor_loc(sb, logical_sb_block, i);
4698                 ext4_sb_breadahead_unmovable(sb, block);
4699         }
4700
4701         for (i = 0; i < db_count; i++) {
4702                 struct buffer_head *bh;
4703
4704                 block = descriptor_loc(sb, logical_sb_block, i);
4705                 bh = ext4_sb_bread_unmovable(sb, block);
4706                 if (IS_ERR(bh)) {
4707                         ext4_msg(sb, KERN_ERR,
4708                                "can't read group descriptor %d", i);
4709                         db_count = i;
4710                         ret = PTR_ERR(bh);
4711                         goto failed_mount2;
4712                 }
4713                 rcu_read_lock();
4714                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4715                 rcu_read_unlock();
4716         }
4717         sbi->s_gdb_count = db_count;
4718         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4719                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4720                 ret = -EFSCORRUPTED;
4721                 goto failed_mount2;
4722         }
4723
4724         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4725         spin_lock_init(&sbi->s_error_lock);
4726         INIT_WORK(&sbi->s_error_work, flush_stashed_error_work);
4727
4728         /* Register extent status tree shrinker */
4729         if (ext4_es_register_shrinker(sbi))
4730                 goto failed_mount3;
4731
4732         sbi->s_stripe = ext4_get_stripe_size(sbi);
4733         sbi->s_extent_max_zeroout_kb = 32;
4734
4735         /*
4736          * set up enough so that it can read an inode
4737          */
4738         sb->s_op = &ext4_sops;
4739         sb->s_export_op = &ext4_export_ops;
4740         sb->s_xattr = ext4_xattr_handlers;
4741 #ifdef CONFIG_FS_ENCRYPTION
4742         sb->s_cop = &ext4_cryptops;
4743 #endif
4744 #ifdef CONFIG_FS_VERITY
4745         sb->s_vop = &ext4_verityops;
4746 #endif
4747 #ifdef CONFIG_QUOTA
4748         sb->dq_op = &ext4_quota_operations;
4749         if (ext4_has_feature_quota(sb))
4750                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4751         else
4752                 sb->s_qcop = &ext4_qctl_operations;
4753         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4754 #endif
4755         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4756
4757         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4758         mutex_init(&sbi->s_orphan_lock);
4759
4760         /* Initialize fast commit stuff */
4761         atomic_set(&sbi->s_fc_subtid, 0);
4762         atomic_set(&sbi->s_fc_ineligible_updates, 0);
4763         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4764         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4765         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4766         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4767         sbi->s_fc_bytes = 0;
4768         ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
4769         ext4_clear_mount_flag(sb, EXT4_MF_FC_COMMITTING);
4770         spin_lock_init(&sbi->s_fc_lock);
4771         memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4772         sbi->s_fc_replay_state.fc_regions = NULL;
4773         sbi->s_fc_replay_state.fc_regions_size = 0;
4774         sbi->s_fc_replay_state.fc_regions_used = 0;
4775         sbi->s_fc_replay_state.fc_regions_valid = 0;
4776         sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4777         sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4778         sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4779
4780         sb->s_root = NULL;
4781
4782         needs_recovery = (es->s_last_orphan != 0 ||
4783                           ext4_has_feature_journal_needs_recovery(sb));
4784
4785         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4786                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4787                         goto failed_mount3a;
4788
4789         /*
4790          * The first inode we look at is the journal inode.  Don't try
4791          * root first: it may be modified in the journal!
4792          */
4793         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4794                 err = ext4_load_journal(sb, es, parsed_opts.journal_devnum);
4795                 if (err)
4796                         goto failed_mount3a;
4797         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4798                    ext4_has_feature_journal_needs_recovery(sb)) {
4799                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4800                        "suppressed and not mounted read-only");
4801                 goto failed_mount_wq;
4802         } else {
4803                 /* Nojournal mode, all journal mount options are illegal */
4804                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4805                         ext4_msg(sb, KERN_ERR, "can't mount with "
4806                                  "journal_checksum, fs mounted w/o journal");
4807                         goto failed_mount_wq;
4808                 }
4809                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4810                         ext4_msg(sb, KERN_ERR, "can't mount with "
4811                                  "journal_async_commit, fs mounted w/o journal");
4812                         goto failed_mount_wq;
4813                 }
4814                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4815                         ext4_msg(sb, KERN_ERR, "can't mount with "
4816                                  "commit=%lu, fs mounted w/o journal",
4817                                  sbi->s_commit_interval / HZ);
4818                         goto failed_mount_wq;
4819                 }
4820                 if (EXT4_MOUNT_DATA_FLAGS &
4821                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4822                         ext4_msg(sb, KERN_ERR, "can't mount with "
4823                                  "data=, fs mounted w/o journal");
4824                         goto failed_mount_wq;
4825                 }
4826                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4827                 clear_opt(sb, JOURNAL_CHECKSUM);
4828                 clear_opt(sb, DATA_FLAGS);
4829                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4830                 sbi->s_journal = NULL;
4831                 needs_recovery = 0;
4832                 goto no_journal;
4833         }
4834
4835         if (ext4_has_feature_64bit(sb) &&
4836             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4837                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4838                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4839                 goto failed_mount_wq;
4840         }
4841
4842         if (!set_journal_csum_feature_set(sb)) {
4843                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4844                          "feature set");
4845                 goto failed_mount_wq;
4846         }
4847
4848         if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4849                 !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4850                                           JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
4851                 ext4_msg(sb, KERN_ERR,
4852                         "Failed to set fast commit journal feature");
4853                 goto failed_mount_wq;
4854         }
4855
4856         /* We have now updated the journal if required, so we can
4857          * validate the data journaling mode. */
4858         switch (test_opt(sb, DATA_FLAGS)) {
4859         case 0:
4860                 /* No mode set, assume a default based on the journal
4861                  * capabilities: ORDERED_DATA if the journal can
4862                  * cope, else JOURNAL_DATA
4863                  */
4864                 if (jbd2_journal_check_available_features
4865                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4866                         set_opt(sb, ORDERED_DATA);
4867                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4868                 } else {
4869                         set_opt(sb, JOURNAL_DATA);
4870                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4871                 }
4872                 break;
4873
4874         case EXT4_MOUNT_ORDERED_DATA:
4875         case EXT4_MOUNT_WRITEBACK_DATA:
4876                 if (!jbd2_journal_check_available_features
4877                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4878                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4879                                "requested data journaling mode");
4880                         goto failed_mount_wq;
4881                 }
4882                 break;
4883         default:
4884                 break;
4885         }
4886
4887         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4888             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4889                 ext4_msg(sb, KERN_ERR, "can't mount with "
4890                         "journal_async_commit in data=ordered mode");
4891                 goto failed_mount_wq;
4892         }
4893
4894         set_task_ioprio(sbi->s_journal->j_task, parsed_opts.journal_ioprio);
4895
4896         sbi->s_journal->j_submit_inode_data_buffers =
4897                 ext4_journal_submit_inode_data_buffers;
4898         sbi->s_journal->j_finish_inode_data_buffers =
4899                 ext4_journal_finish_inode_data_buffers;
4900
4901 no_journal:
4902         if (!test_opt(sb, NO_MBCACHE)) {
4903                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4904                 if (!sbi->s_ea_block_cache) {
4905                         ext4_msg(sb, KERN_ERR,
4906                                  "Failed to create ea_block_cache");
4907                         goto failed_mount_wq;
4908                 }
4909
4910                 if (ext4_has_feature_ea_inode(sb)) {
4911                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4912                         if (!sbi->s_ea_inode_cache) {
4913                                 ext4_msg(sb, KERN_ERR,
4914                                          "Failed to create ea_inode_cache");
4915                                 goto failed_mount_wq;
4916                         }
4917                 }
4918         }
4919
4920         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4921                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4922                 goto failed_mount_wq;
4923         }
4924
4925         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4926             !ext4_has_feature_encrypt(sb)) {
4927                 ext4_set_feature_encrypt(sb);
4928                 ext4_commit_super(sb);
4929         }
4930
4931         /*
4932          * Get the # of file system overhead blocks from the
4933          * superblock if present.
4934          */
4935         if (es->s_overhead_clusters)
4936                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4937         else {
4938                 err = ext4_calculate_overhead(sb);
4939                 if (err)
4940                         goto failed_mount_wq;
4941         }
4942
4943         /*
4944          * The maximum number of concurrent works can be high and
4945          * concurrency isn't really necessary.  Limit it to 1.
4946          */
4947         EXT4_SB(sb)->rsv_conversion_wq =
4948                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4949         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4950                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4951                 ret = -ENOMEM;
4952                 goto failed_mount4;
4953         }
4954
4955         /*
4956          * The jbd2_journal_load will have done any necessary log recovery,
4957          * so we can safely mount the rest of the filesystem now.
4958          */
4959
4960         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4961         if (IS_ERR(root)) {
4962                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4963                 ret = PTR_ERR(root);
4964                 root = NULL;
4965                 goto failed_mount4;
4966         }
4967         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4968                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4969                 iput(root);
4970                 goto failed_mount4;
4971         }
4972
4973         sb->s_root = d_make_root(root);
4974         if (!sb->s_root) {
4975                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4976                 ret = -ENOMEM;
4977                 goto failed_mount4;
4978         }
4979
4980         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4981         if (ret == -EROFS) {
4982                 sb->s_flags |= SB_RDONLY;
4983                 ret = 0;
4984         } else if (ret)
4985                 goto failed_mount4a;
4986
4987         ext4_set_resv_clusters(sb);
4988
4989         if (test_opt(sb, BLOCK_VALIDITY)) {
4990                 err = ext4_setup_system_zone(sb);
4991                 if (err) {
4992                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
4993                                  "zone (%d)", err);
4994                         goto failed_mount4a;
4995                 }
4996         }
4997         ext4_fc_replay_cleanup(sb);
4998
4999         ext4_ext_init(sb);
5000
5001         /*
5002          * Enable optimize_scan if number of groups is > threshold. This can be
5003          * turned off by passing "mb_optimize_scan=0". This can also be
5004          * turned on forcefully by passing "mb_optimize_scan=1".
5005          */
5006         if (parsed_opts.mb_optimize_scan == 1)
5007                 set_opt2(sb, MB_OPTIMIZE_SCAN);
5008         else if (parsed_opts.mb_optimize_scan == 0)
5009                 clear_opt2(sb, MB_OPTIMIZE_SCAN);
5010         else if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
5011                 set_opt2(sb, MB_OPTIMIZE_SCAN);
5012
5013         err = ext4_mb_init(sb);
5014         if (err) {
5015                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5016                          err);
5017                 goto failed_mount5;
5018         }
5019
5020         /*
5021          * We can only set up the journal commit callback once
5022          * mballoc is initialized
5023          */
5024         if (sbi->s_journal)
5025                 sbi->s_journal->j_commit_callback =
5026                         ext4_journal_commit_callback;
5027
5028         block = ext4_count_free_clusters(sb);
5029         ext4_free_blocks_count_set(sbi->s_es,
5030                                    EXT4_C2B(sbi, block));
5031         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
5032                                   GFP_KERNEL);
5033         if (!err) {
5034                 unsigned long freei = ext4_count_free_inodes(sb);
5035                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
5036                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
5037                                           GFP_KERNEL);
5038         }
5039         if (!err)
5040                 err = percpu_counter_init(&sbi->s_dirs_counter,
5041                                           ext4_count_dirs(sb), GFP_KERNEL);
5042         if (!err)
5043                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
5044                                           GFP_KERNEL);
5045         if (!err)
5046                 err = percpu_counter_init(&sbi->s_sra_exceeded_retry_limit, 0,
5047                                           GFP_KERNEL);
5048         if (!err)
5049                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
5050
5051         if (err) {
5052                 ext4_msg(sb, KERN_ERR, "insufficient memory");
5053                 goto failed_mount6;
5054         }
5055
5056         if (ext4_has_feature_flex_bg(sb))
5057                 if (!ext4_fill_flex_info(sb)) {
5058                         ext4_msg(sb, KERN_ERR,
5059                                "unable to initialize "
5060                                "flex_bg meta info!");
5061                         goto failed_mount6;
5062                 }
5063
5064         err = ext4_register_li_request(sb, first_not_zeroed);
5065         if (err)
5066                 goto failed_mount6;
5067
5068         err = ext4_register_sysfs(sb);
5069         if (err)
5070                 goto failed_mount7;
5071
5072 #ifdef CONFIG_QUOTA
5073         /* Enable quota usage during mount. */
5074         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5075                 err = ext4_enable_quotas(sb);
5076                 if (err)
5077                         goto failed_mount8;
5078         }
5079 #endif  /* CONFIG_QUOTA */
5080
5081         /*
5082          * Save the original bdev mapping's wb_err value which could be
5083          * used to detect the metadata async write error.
5084          */
5085         spin_lock_init(&sbi->s_bdev_wb_lock);
5086         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5087                                  &sbi->s_bdev_wb_err);
5088         sb->s_bdev->bd_super = sb;
5089         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5090         ext4_orphan_cleanup(sb, es);
5091         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5092         if (needs_recovery) {
5093                 ext4_msg(sb, KERN_INFO, "recovery complete");
5094                 err = ext4_mark_recovery_complete(sb, es);
5095                 if (err)
5096                         goto failed_mount8;
5097         }
5098         if (EXT4_SB(sb)->s_journal) {
5099                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5100                         descr = " journalled data mode";
5101                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5102                         descr = " ordered data mode";
5103                 else
5104                         descr = " writeback data mode";
5105         } else
5106                 descr = "out journal";
5107
5108         if (test_opt(sb, DISCARD)) {
5109                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
5110                 if (!blk_queue_discard(q))
5111                         ext4_msg(sb, KERN_WARNING,
5112                                  "mounting with \"discard\" option, but "
5113                                  "the device does not support discard");
5114         }
5115
5116         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5117                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
5118                          "Opts: %.*s%s%s. Quota mode: %s.", descr,
5119                          (int) sizeof(sbi->s_es->s_mount_opts),
5120                          sbi->s_es->s_mount_opts,
5121                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data,
5122                          ext4_quota_mode(sb));
5123
5124         if (es->s_error_count)
5125                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5126
5127         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5128         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5129         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5130         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5131         atomic_set(&sbi->s_warning_count, 0);
5132         atomic_set(&sbi->s_msg_count, 0);
5133
5134         kfree(orig_data);
5135         return 0;
5136
5137 cantfind_ext4:
5138         if (!silent)
5139                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5140         goto failed_mount;
5141
5142 failed_mount8:
5143         ext4_unregister_sysfs(sb);
5144         kobject_put(&sbi->s_kobj);
5145 failed_mount7:
5146         ext4_unregister_li_request(sb);
5147 failed_mount6:
5148         ext4_mb_release(sb);
5149         rcu_read_lock();
5150         flex_groups = rcu_dereference(sbi->s_flex_groups);
5151         if (flex_groups) {
5152                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
5153                         kvfree(flex_groups[i]);
5154                 kvfree(flex_groups);
5155         }
5156         rcu_read_unlock();
5157         percpu_counter_destroy(&sbi->s_freeclusters_counter);
5158         percpu_counter_destroy(&sbi->s_freeinodes_counter);
5159         percpu_counter_destroy(&sbi->s_dirs_counter);
5160         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
5161         percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
5162         percpu_free_rwsem(&sbi->s_writepages_rwsem);
5163 failed_mount5:
5164         ext4_ext_release(sb);
5165         ext4_release_system_zone(sb);
5166 failed_mount4a:
5167         dput(sb->s_root);
5168         sb->s_root = NULL;
5169 failed_mount4:
5170         ext4_msg(sb, KERN_ERR, "mount failed");
5171         if (EXT4_SB(sb)->rsv_conversion_wq)
5172                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5173 failed_mount_wq:
5174         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5175         sbi->s_ea_inode_cache = NULL;
5176
5177         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5178         sbi->s_ea_block_cache = NULL;
5179
5180         if (sbi->s_journal) {
5181                 jbd2_journal_destroy(sbi->s_journal);
5182                 sbi->s_journal = NULL;
5183         }
5184 failed_mount3a:
5185         ext4_es_unregister_shrinker(sbi);
5186 failed_mount3:
5187         flush_work(&sbi->s_error_work);
5188         del_timer_sync(&sbi->s_err_report);
5189         ext4_stop_mmpd(sbi);
5190 failed_mount2:
5191         rcu_read_lock();
5192         group_desc = rcu_dereference(sbi->s_group_desc);
5193         for (i = 0; i < db_count; i++)
5194                 brelse(group_desc[i]);
5195         kvfree(group_desc);
5196         rcu_read_unlock();
5197 failed_mount:
5198         if (sbi->s_chksum_driver)
5199                 crypto_free_shash(sbi->s_chksum_driver);
5200
5201 #ifdef CONFIG_UNICODE
5202         utf8_unload(sb->s_encoding);
5203 #endif
5204
5205 #ifdef CONFIG_QUOTA
5206         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5207                 kfree(get_qf_name(sb, sbi, i));
5208 #endif
5209         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5210         /* ext4_blkdev_remove() calls kill_bdev(), release bh before it. */
5211         brelse(bh);
5212         ext4_blkdev_remove(sbi);
5213 out_fail:
5214         sb->s_fs_info = NULL;
5215         kfree(sbi->s_blockgroup_lock);
5216 out_free_base:
5217         kfree(sbi);
5218         kfree(orig_data);
5219         fs_put_dax(dax_dev);
5220         return err ? err : ret;
5221 }
5222
5223 /*
5224  * Setup any per-fs journal parameters now.  We'll do this both on
5225  * initial mount, once the journal has been initialised but before we've
5226  * done any recovery; and again on any subsequent remount.
5227  */
5228 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5229 {
5230         struct ext4_sb_info *sbi = EXT4_SB(sb);
5231
5232         journal->j_commit_interval = sbi->s_commit_interval;
5233         journal->j_min_batch_time = sbi->s_min_batch_time;
5234         journal->j_max_batch_time = sbi->s_max_batch_time;
5235         ext4_fc_init(sb, journal);
5236
5237         write_lock(&journal->j_state_lock);
5238         if (test_opt(sb, BARRIER))
5239                 journal->j_flags |= JBD2_BARRIER;
5240         else
5241                 journal->j_flags &= ~JBD2_BARRIER;
5242         if (test_opt(sb, DATA_ERR_ABORT))
5243                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5244         else
5245                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5246         write_unlock(&journal->j_state_lock);
5247 }
5248
5249 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5250                                              unsigned int journal_inum)
5251 {
5252         struct inode *journal_inode;
5253
5254         /*
5255          * Test for the existence of a valid inode on disk.  Bad things
5256          * happen if we iget() an unused inode, as the subsequent iput()
5257          * will try to delete it.
5258          */
5259         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5260         if (IS_ERR(journal_inode)) {
5261                 ext4_msg(sb, KERN_ERR, "no journal found");
5262                 return NULL;
5263         }
5264         if (!journal_inode->i_nlink) {
5265                 make_bad_inode(journal_inode);
5266                 iput(journal_inode);
5267                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5268                 return NULL;
5269         }
5270
5271         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
5272                   journal_inode, journal_inode->i_size);
5273         if (!S_ISREG(journal_inode->i_mode)) {
5274                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5275                 iput(journal_inode);
5276                 return NULL;
5277         }
5278         return journal_inode;
5279 }
5280
5281 static journal_t *ext4_get_journal(struct super_block *sb,
5282                                    unsigned int journal_inum)
5283 {
5284         struct inode *journal_inode;
5285         journal_t *journal;
5286
5287         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5288                 return NULL;
5289
5290         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5291         if (!journal_inode)
5292                 return NULL;
5293
5294         journal = jbd2_journal_init_inode(journal_inode);
5295         if (!journal) {
5296                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5297                 iput(journal_inode);
5298                 return NULL;
5299         }
5300         journal->j_private = sb;
5301         ext4_init_journal_params(sb, journal);
5302         return journal;
5303 }
5304
5305 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5306                                        dev_t j_dev)
5307 {
5308         struct buffer_head *bh;
5309         journal_t *journal;
5310         ext4_fsblk_t start;
5311         ext4_fsblk_t len;
5312         int hblock, blocksize;
5313         ext4_fsblk_t sb_block;
5314         unsigned long offset;
5315         struct ext4_super_block *es;
5316         struct block_device *bdev;
5317
5318         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5319                 return NULL;
5320
5321         bdev = ext4_blkdev_get(j_dev, sb);
5322         if (bdev == NULL)
5323                 return NULL;
5324
5325         blocksize = sb->s_blocksize;
5326         hblock = bdev_logical_block_size(bdev);
5327         if (blocksize < hblock) {
5328                 ext4_msg(sb, KERN_ERR,
5329                         "blocksize too small for journal device");
5330                 goto out_bdev;
5331         }
5332
5333         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5334         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5335         set_blocksize(bdev, blocksize);
5336         if (!(bh = __bread(bdev, sb_block, blocksize))) {
5337                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5338                        "external journal");
5339                 goto out_bdev;
5340         }
5341
5342         es = (struct ext4_super_block *) (bh->b_data + offset);
5343         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5344             !(le32_to_cpu(es->s_feature_incompat) &
5345               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5346                 ext4_msg(sb, KERN_ERR, "external journal has "
5347                                         "bad superblock");
5348                 brelse(bh);
5349                 goto out_bdev;
5350         }
5351
5352         if ((le32_to_cpu(es->s_feature_ro_compat) &
5353              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5354             es->s_checksum != ext4_superblock_csum(sb, es)) {
5355                 ext4_msg(sb, KERN_ERR, "external journal has "
5356                                        "corrupt superblock");
5357                 brelse(bh);
5358                 goto out_bdev;
5359         }
5360
5361         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5362                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5363                 brelse(bh);
5364                 goto out_bdev;
5365         }
5366
5367         len = ext4_blocks_count(es);
5368         start = sb_block + 1;
5369         brelse(bh);     /* we're done with the superblock */
5370
5371         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5372                                         start, len, blocksize);
5373         if (!journal) {
5374                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5375                 goto out_bdev;
5376         }
5377         journal->j_private = sb;
5378         if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
5379                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5380                 goto out_journal;
5381         }
5382         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5383                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5384                                         "user (unsupported) - %d",
5385                         be32_to_cpu(journal->j_superblock->s_nr_users));
5386                 goto out_journal;
5387         }
5388         EXT4_SB(sb)->s_journal_bdev = bdev;
5389         ext4_init_journal_params(sb, journal);
5390         return journal;
5391
5392 out_journal:
5393         jbd2_journal_destroy(journal);
5394 out_bdev:
5395         ext4_blkdev_put(bdev);
5396         return NULL;
5397 }
5398
5399 static int ext4_load_journal(struct super_block *sb,
5400                              struct ext4_super_block *es,
5401                              unsigned long journal_devnum)
5402 {
5403         journal_t *journal;
5404         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5405         dev_t journal_dev;
5406         int err = 0;
5407         int really_read_only;
5408         int journal_dev_ro;
5409
5410         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5411                 return -EFSCORRUPTED;
5412
5413         if (journal_devnum &&
5414             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5415                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5416                         "numbers have changed");
5417                 journal_dev = new_decode_dev(journal_devnum);
5418         } else
5419                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5420
5421         if (journal_inum && journal_dev) {
5422                 ext4_msg(sb, KERN_ERR,
5423                          "filesystem has both journal inode and journal device!");
5424                 return -EINVAL;
5425         }
5426
5427         if (journal_inum) {
5428                 journal = ext4_get_journal(sb, journal_inum);
5429                 if (!journal)
5430                         return -EINVAL;
5431         } else {
5432                 journal = ext4_get_dev_journal(sb, journal_dev);
5433                 if (!journal)
5434                         return -EINVAL;
5435         }
5436
5437         journal_dev_ro = bdev_read_only(journal->j_dev);
5438         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5439
5440         if (journal_dev_ro && !sb_rdonly(sb)) {
5441                 ext4_msg(sb, KERN_ERR,
5442                          "journal device read-only, try mounting with '-o ro'");
5443                 err = -EROFS;
5444                 goto err_out;
5445         }
5446
5447         /*
5448          * Are we loading a blank journal or performing recovery after a
5449          * crash?  For recovery, we need to check in advance whether we
5450          * can get read-write access to the device.
5451          */
5452         if (ext4_has_feature_journal_needs_recovery(sb)) {
5453                 if (sb_rdonly(sb)) {
5454                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5455                                         "required on readonly filesystem");
5456                         if (really_read_only) {
5457                                 ext4_msg(sb, KERN_ERR, "write access "
5458                                         "unavailable, cannot proceed "
5459                                         "(try mounting with noload)");
5460                                 err = -EROFS;
5461                                 goto err_out;
5462                         }
5463                         ext4_msg(sb, KERN_INFO, "write access will "
5464                                "be enabled during recovery");
5465                 }
5466         }
5467
5468         if (!(journal->j_flags & JBD2_BARRIER))
5469                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5470
5471         if (!ext4_has_feature_journal_needs_recovery(sb))
5472                 err = jbd2_journal_wipe(journal, !really_read_only);
5473         if (!err) {
5474                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5475                 if (save)
5476                         memcpy(save, ((char *) es) +
5477                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5478                 err = jbd2_journal_load(journal);
5479                 if (save)
5480                         memcpy(((char *) es) + EXT4_S_ERR_START,
5481                                save, EXT4_S_ERR_LEN);
5482                 kfree(save);
5483         }
5484
5485         if (err) {
5486                 ext4_msg(sb, KERN_ERR, "error loading journal");
5487                 goto err_out;
5488         }
5489
5490         EXT4_SB(sb)->s_journal = journal;
5491         err = ext4_clear_journal_err(sb, es);
5492         if (err) {
5493                 EXT4_SB(sb)->s_journal = NULL;
5494                 jbd2_journal_destroy(journal);
5495                 return err;
5496         }
5497
5498         if (!really_read_only && journal_devnum &&
5499             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5500                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5501
5502                 /* Make sure we flush the recovery flag to disk. */
5503                 ext4_commit_super(sb);
5504         }
5505
5506         return 0;
5507
5508 err_out:
5509         jbd2_journal_destroy(journal);
5510         return err;
5511 }
5512
5513 /* Copy state of EXT4_SB(sb) into buffer for on-disk superblock */
5514 static void ext4_update_super(struct super_block *sb)
5515 {
5516         struct ext4_sb_info *sbi = EXT4_SB(sb);
5517         struct ext4_super_block *es = sbi->s_es;
5518         struct buffer_head *sbh = sbi->s_sbh;
5519
5520         lock_buffer(sbh);
5521         /*
5522          * If the file system is mounted read-only, don't update the
5523          * superblock write time.  This avoids updating the superblock
5524          * write time when we are mounting the root file system
5525          * read/only but we need to replay the journal; at that point,
5526          * for people who are east of GMT and who make their clock
5527          * tick in localtime for Windows bug-for-bug compatibility,
5528          * the clock is set in the future, and this will cause e2fsck
5529          * to complain and force a full file system check.
5530          */
5531         if (!(sb->s_flags & SB_RDONLY))
5532                 ext4_update_tstamp(es, s_wtime);
5533         es->s_kbytes_written =
5534                 cpu_to_le64(sbi->s_kbytes_written +
5535                     ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
5536                       sbi->s_sectors_written_start) >> 1));
5537         if (percpu_counter_initialized(&sbi->s_freeclusters_counter))
5538                 ext4_free_blocks_count_set(es,
5539                         EXT4_C2B(sbi, percpu_counter_sum_positive(
5540                                 &sbi->s_freeclusters_counter)));
5541         if (percpu_counter_initialized(&sbi->s_freeinodes_counter))
5542                 es->s_free_inodes_count =
5543                         cpu_to_le32(percpu_counter_sum_positive(
5544                                 &sbi->s_freeinodes_counter));
5545         /* Copy error information to the on-disk superblock */
5546         spin_lock(&sbi->s_error_lock);
5547         if (sbi->s_add_error_count > 0) {
5548                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5549                 if (!es->s_first_error_time && !es->s_first_error_time_hi) {
5550                         __ext4_update_tstamp(&es->s_first_error_time,
5551                                              &es->s_first_error_time_hi,
5552                                              sbi->s_first_error_time);
5553                         strncpy(es->s_first_error_func, sbi->s_first_error_func,
5554                                 sizeof(es->s_first_error_func));
5555                         es->s_first_error_line =
5556                                 cpu_to_le32(sbi->s_first_error_line);
5557                         es->s_first_error_ino =
5558                                 cpu_to_le32(sbi->s_first_error_ino);
5559                         es->s_first_error_block =
5560                                 cpu_to_le64(sbi->s_first_error_block);
5561                         es->s_first_error_errcode =
5562                                 ext4_errno_to_code(sbi->s_first_error_code);
5563                 }
5564                 __ext4_update_tstamp(&es->s_last_error_time,
5565                                      &es->s_last_error_time_hi,
5566                                      sbi->s_last_error_time);
5567                 strncpy(es->s_last_error_func, sbi->s_last_error_func,
5568                         sizeof(es->s_last_error_func));
5569                 es->s_last_error_line = cpu_to_le32(sbi->s_last_error_line);
5570                 es->s_last_error_ino = cpu_to_le32(sbi->s_last_error_ino);
5571                 es->s_last_error_block = cpu_to_le64(sbi->s_last_error_block);
5572                 es->s_last_error_errcode =
5573                                 ext4_errno_to_code(sbi->s_last_error_code);
5574                 /*
5575                  * Start the daily error reporting function if it hasn't been
5576                  * started already
5577                  */
5578                 if (!es->s_error_count)
5579                         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
5580                 le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
5581                 sbi->s_add_error_count = 0;
5582         }
5583         spin_unlock(&sbi->s_error_lock);
5584
5585         ext4_superblock_csum_set(sb);
5586         unlock_buffer(sbh);
5587 }
5588
5589 static int ext4_commit_super(struct super_block *sb)
5590 {
5591         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5592         int error = 0;
5593
5594         if (!sbh)
5595                 return -EINVAL;
5596         if (block_device_ejected(sb))
5597                 return -ENODEV;
5598
5599         ext4_update_super(sb);
5600
5601         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5602                 /*
5603                  * Oh, dear.  A previous attempt to write the
5604                  * superblock failed.  This could happen because the
5605                  * USB device was yanked out.  Or it could happen to
5606                  * be a transient write error and maybe the block will
5607                  * be remapped.  Nothing we can do but to retry the
5608                  * write and hope for the best.
5609                  */
5610                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5611                        "superblock detected");
5612                 clear_buffer_write_io_error(sbh);
5613                 set_buffer_uptodate(sbh);
5614         }
5615         BUFFER_TRACE(sbh, "marking dirty");
5616         mark_buffer_dirty(sbh);
5617         error = __sync_dirty_buffer(sbh,
5618                 REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5619         if (buffer_write_io_error(sbh)) {
5620                 ext4_msg(sb, KERN_ERR, "I/O error while writing "
5621                        "superblock");
5622                 clear_buffer_write_io_error(sbh);
5623                 set_buffer_uptodate(sbh);
5624         }
5625         return error;
5626 }
5627
5628 /*
5629  * Have we just finished recovery?  If so, and if we are mounting (or
5630  * remounting) the filesystem readonly, then we will end up with a
5631  * consistent fs on disk.  Record that fact.
5632  */
5633 static int ext4_mark_recovery_complete(struct super_block *sb,
5634                                        struct ext4_super_block *es)
5635 {
5636         int err;
5637         journal_t *journal = EXT4_SB(sb)->s_journal;
5638
5639         if (!ext4_has_feature_journal(sb)) {
5640                 if (journal != NULL) {
5641                         ext4_error(sb, "Journal got removed while the fs was "
5642                                    "mounted!");
5643                         return -EFSCORRUPTED;
5644                 }
5645                 return 0;
5646         }
5647         jbd2_journal_lock_updates(journal);
5648         err = jbd2_journal_flush(journal);
5649         if (err < 0)
5650                 goto out;
5651
5652         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5653                 ext4_clear_feature_journal_needs_recovery(sb);
5654                 ext4_commit_super(sb);
5655         }
5656 out:
5657         jbd2_journal_unlock_updates(journal);
5658         return err;
5659 }
5660
5661 /*
5662  * If we are mounting (or read-write remounting) a filesystem whose journal
5663  * has recorded an error from a previous lifetime, move that error to the
5664  * main filesystem now.
5665  */
5666 static int ext4_clear_journal_err(struct super_block *sb,
5667                                    struct ext4_super_block *es)
5668 {
5669         journal_t *journal;
5670         int j_errno;
5671         const char *errstr;
5672
5673         if (!ext4_has_feature_journal(sb)) {
5674                 ext4_error(sb, "Journal got removed while the fs was mounted!");
5675                 return -EFSCORRUPTED;
5676         }
5677
5678         journal = EXT4_SB(sb)->s_journal;
5679
5680         /*
5681          * Now check for any error status which may have been recorded in the
5682          * journal by a prior ext4_error() or ext4_abort()
5683          */
5684
5685         j_errno = jbd2_journal_errno(journal);
5686         if (j_errno) {
5687                 char nbuf[16];
5688
5689                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5690                 ext4_warning(sb, "Filesystem error recorded "
5691                              "from previous mount: %s", errstr);
5692                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5693
5694                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5695                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5696                 ext4_commit_super(sb);
5697
5698                 jbd2_journal_clear_err(journal);
5699                 jbd2_journal_update_sb_errno(journal);
5700         }
5701         return 0;
5702 }
5703
5704 /*
5705  * Force the running and committing transactions to commit,
5706  * and wait on the commit.
5707  */
5708 int ext4_force_commit(struct super_block *sb)
5709 {
5710         journal_t *journal;
5711
5712         if (sb_rdonly(sb))
5713                 return 0;
5714
5715         journal = EXT4_SB(sb)->s_journal;
5716         return ext4_journal_force_commit(journal);
5717 }
5718
5719 static int ext4_sync_fs(struct super_block *sb, int wait)
5720 {
5721         int ret = 0;
5722         tid_t target;
5723         bool needs_barrier = false;
5724         struct ext4_sb_info *sbi = EXT4_SB(sb);
5725
5726         if (unlikely(ext4_forced_shutdown(sbi)))
5727                 return 0;
5728
5729         trace_ext4_sync_fs(sb, wait);
5730         flush_workqueue(sbi->rsv_conversion_wq);
5731         /*
5732          * Writeback quota in non-journalled quota case - journalled quota has
5733          * no dirty dquots
5734          */
5735         dquot_writeback_dquots(sb, -1);
5736         /*
5737          * Data writeback is possible w/o journal transaction, so barrier must
5738          * being sent at the end of the function. But we can skip it if
5739          * transaction_commit will do it for us.
5740          */
5741         if (sbi->s_journal) {
5742                 target = jbd2_get_latest_transaction(sbi->s_journal);
5743                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5744                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5745                         needs_barrier = true;
5746
5747                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5748                         if (wait)
5749                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5750                                                            target);
5751                 }
5752         } else if (wait && test_opt(sb, BARRIER))
5753                 needs_barrier = true;
5754         if (needs_barrier) {
5755                 int err;
5756                 err = blkdev_issue_flush(sb->s_bdev);
5757                 if (!ret)
5758                         ret = err;
5759         }
5760
5761         return ret;
5762 }
5763
5764 /*
5765  * LVM calls this function before a (read-only) snapshot is created.  This
5766  * gives us a chance to flush the journal completely and mark the fs clean.
5767  *
5768  * Note that only this function cannot bring a filesystem to be in a clean
5769  * state independently. It relies on upper layer to stop all data & metadata
5770  * modifications.
5771  */
5772 static int ext4_freeze(struct super_block *sb)
5773 {
5774         int error = 0;
5775         journal_t *journal;
5776
5777         if (sb_rdonly(sb))
5778                 return 0;
5779
5780         journal = EXT4_SB(sb)->s_journal;
5781
5782         if (journal) {
5783                 /* Now we set up the journal barrier. */
5784                 jbd2_journal_lock_updates(journal);
5785
5786                 /*
5787                  * Don't clear the needs_recovery flag if we failed to
5788                  * flush the journal.
5789                  */
5790                 error = jbd2_journal_flush(journal);
5791                 if (error < 0)
5792                         goto out;
5793
5794                 /* Journal blocked and flushed, clear needs_recovery flag. */
5795                 ext4_clear_feature_journal_needs_recovery(sb);
5796         }
5797
5798         error = ext4_commit_super(sb);
5799 out:
5800         if (journal)
5801                 /* we rely on upper layer to stop further updates */
5802                 jbd2_journal_unlock_updates(journal);
5803         return error;
5804 }
5805
5806 /*
5807  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5808  * flag here, even though the filesystem is not technically dirty yet.
5809  */
5810 static int ext4_unfreeze(struct super_block *sb)
5811 {
5812         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5813                 return 0;
5814
5815         if (EXT4_SB(sb)->s_journal) {
5816                 /* Reset the needs_recovery flag before the fs is unlocked. */
5817                 ext4_set_feature_journal_needs_recovery(sb);
5818         }
5819
5820         ext4_commit_super(sb);
5821         return 0;
5822 }
5823
5824 /*
5825  * Structure to save mount options for ext4_remount's benefit
5826  */
5827 struct ext4_mount_options {
5828         unsigned long s_mount_opt;
5829         unsigned long s_mount_opt2;
5830         kuid_t s_resuid;
5831         kgid_t s_resgid;
5832         unsigned long s_commit_interval;
5833         u32 s_min_batch_time, s_max_batch_time;
5834 #ifdef CONFIG_QUOTA
5835         int s_jquota_fmt;
5836         char *s_qf_names[EXT4_MAXQUOTAS];
5837 #endif
5838 };
5839
5840 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5841 {
5842         struct ext4_super_block *es;
5843         struct ext4_sb_info *sbi = EXT4_SB(sb);
5844         unsigned long old_sb_flags, vfs_flags;
5845         struct ext4_mount_options old_opts;
5846         int enable_quota = 0;
5847         ext4_group_t g;
5848         int err = 0;
5849 #ifdef CONFIG_QUOTA
5850         int i, j;
5851         char *to_free[EXT4_MAXQUOTAS];
5852 #endif
5853         char *orig_data = kstrdup(data, GFP_KERNEL);
5854         struct ext4_parsed_options parsed_opts;
5855
5856         parsed_opts.journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5857         parsed_opts.journal_devnum = 0;
5858
5859         if (data && !orig_data)
5860                 return -ENOMEM;
5861
5862         /* Store the original options */
5863         old_sb_flags = sb->s_flags;
5864         old_opts.s_mount_opt = sbi->s_mount_opt;
5865         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5866         old_opts.s_resuid = sbi->s_resuid;
5867         old_opts.s_resgid = sbi->s_resgid;
5868         old_opts.s_commit_interval = sbi->s_commit_interval;
5869         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5870         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5871 #ifdef CONFIG_QUOTA
5872         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5873         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5874                 if (sbi->s_qf_names[i]) {
5875                         char *qf_name = get_qf_name(sb, sbi, i);
5876
5877                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5878                         if (!old_opts.s_qf_names[i]) {
5879                                 for (j = 0; j < i; j++)
5880                                         kfree(old_opts.s_qf_names[j]);
5881                                 kfree(orig_data);
5882                                 return -ENOMEM;
5883                         }
5884                 } else
5885                         old_opts.s_qf_names[i] = NULL;
5886 #endif
5887         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5888                 parsed_opts.journal_ioprio =
5889                         sbi->s_journal->j_task->io_context->ioprio;
5890
5891         /*
5892          * Some options can be enabled by ext4 and/or by VFS mount flag
5893          * either way we need to make sure it matches in both *flags and
5894          * s_flags. Copy those selected flags from *flags to s_flags
5895          */
5896         vfs_flags = SB_LAZYTIME | SB_I_VERSION;
5897         sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags);
5898
5899         if (!parse_options(data, sb, &parsed_opts, 1)) {
5900                 err = -EINVAL;
5901                 goto restore_opts;
5902         }
5903
5904         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5905             test_opt(sb, JOURNAL_CHECKSUM)) {
5906                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5907                          "during remount not supported; ignoring");
5908                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5909         }
5910
5911         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5912                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5913                         ext4_msg(sb, KERN_ERR, "can't mount with "
5914                                  "both data=journal and delalloc");
5915                         err = -EINVAL;
5916                         goto restore_opts;
5917                 }
5918                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5919                         ext4_msg(sb, KERN_ERR, "can't mount with "
5920                                  "both data=journal and dioread_nolock");
5921                         err = -EINVAL;
5922                         goto restore_opts;
5923                 }
5924         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5925                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5926                         ext4_msg(sb, KERN_ERR, "can't mount with "
5927                                 "journal_async_commit in data=ordered mode");
5928                         err = -EINVAL;
5929                         goto restore_opts;
5930                 }
5931         }
5932
5933         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5934                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5935                 err = -EINVAL;
5936                 goto restore_opts;
5937         }
5938
5939         if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED))
5940                 ext4_abort(sb, EXT4_ERR_ESHUTDOWN, "Abort forced by user");
5941
5942         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5943                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5944
5945         es = sbi->s_es;
5946
5947         if (sbi->s_journal) {
5948                 ext4_init_journal_params(sb, sbi->s_journal);
5949                 set_task_ioprio(sbi->s_journal->j_task, parsed_opts.journal_ioprio);
5950         }
5951
5952         /* Flush outstanding errors before changing fs state */
5953         flush_work(&sbi->s_error_work);
5954
5955         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5956                 if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED)) {
5957                         err = -EROFS;
5958                         goto restore_opts;
5959                 }
5960
5961                 if (*flags & SB_RDONLY) {
5962                         err = sync_filesystem(sb);
5963                         if (err < 0)
5964                                 goto restore_opts;
5965                         err = dquot_suspend(sb, -1);
5966                         if (err < 0)
5967                                 goto restore_opts;
5968
5969                         /*
5970                          * First of all, the unconditional stuff we have to do
5971                          * to disable replay of the journal when we next remount
5972                          */
5973                         sb->s_flags |= SB_RDONLY;
5974
5975                         /*
5976                          * OK, test if we are remounting a valid rw partition
5977                          * readonly, and if so set the rdonly flag and then
5978                          * mark the partition as valid again.
5979                          */
5980                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5981                             (sbi->s_mount_state & EXT4_VALID_FS))
5982                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5983
5984                         if (sbi->s_journal) {
5985                                 /*
5986                                  * We let remount-ro finish even if marking fs
5987                                  * as clean failed...
5988                                  */
5989                                 ext4_mark_recovery_complete(sb, es);
5990                         }
5991                         ext4_stop_mmpd(sbi);
5992                 } else {
5993                         /* Make sure we can mount this feature set readwrite */
5994                         if (ext4_has_feature_readonly(sb) ||
5995                             !ext4_feature_set_ok(sb, 0)) {
5996                                 err = -EROFS;
5997                                 goto restore_opts;
5998                         }
5999                         /*
6000                          * Make sure the group descriptor checksums
6001                          * are sane.  If they aren't, refuse to remount r/w.
6002                          */
6003                         for (g = 0; g < sbi->s_groups_count; g++) {
6004                                 struct ext4_group_desc *gdp =
6005                                         ext4_get_group_desc(sb, g, NULL);
6006
6007                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
6008                                         ext4_msg(sb, KERN_ERR,
6009                "ext4_remount: Checksum for group %u failed (%u!=%u)",
6010                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
6011                                                le16_to_cpu(gdp->bg_checksum));
6012                                         err = -EFSBADCRC;
6013                                         goto restore_opts;
6014                                 }
6015                         }
6016
6017                         /*
6018                          * If we have an unprocessed orphan list hanging
6019                          * around from a previously readonly bdev mount,
6020                          * require a full umount/remount for now.
6021                          */
6022                         if (es->s_last_orphan) {
6023                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
6024                                        "remount RDWR because of unprocessed "
6025                                        "orphan inode list.  Please "
6026                                        "umount/remount instead");
6027                                 err = -EINVAL;
6028                                 goto restore_opts;
6029                         }
6030
6031                         /*
6032                          * Mounting a RDONLY partition read-write, so reread
6033                          * and store the current valid flag.  (It may have
6034                          * been changed by e2fsck since we originally mounted
6035                          * the partition.)
6036                          */
6037                         if (sbi->s_journal) {
6038                                 err = ext4_clear_journal_err(sb, es);
6039                                 if (err)
6040                                         goto restore_opts;
6041                         }
6042                         sbi->s_mount_state = le16_to_cpu(es->s_state);
6043
6044                         err = ext4_setup_super(sb, es, 0);
6045                         if (err)
6046                                 goto restore_opts;
6047
6048                         sb->s_flags &= ~SB_RDONLY;
6049                         if (ext4_has_feature_mmp(sb))
6050                                 if (ext4_multi_mount_protect(sb,
6051                                                 le64_to_cpu(es->s_mmp_block))) {
6052                                         err = -EROFS;
6053                                         goto restore_opts;
6054                                 }
6055                         enable_quota = 1;
6056                 }
6057         }
6058
6059         /*
6060          * Reinitialize lazy itable initialization thread based on
6061          * current settings
6062          */
6063         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
6064                 ext4_unregister_li_request(sb);
6065         else {
6066                 ext4_group_t first_not_zeroed;
6067                 first_not_zeroed = ext4_has_uninit_itable(sb);
6068                 ext4_register_li_request(sb, first_not_zeroed);
6069         }
6070
6071         /*
6072          * Handle creation of system zone data early because it can fail.
6073          * Releasing of existing data is done when we are sure remount will
6074          * succeed.
6075          */
6076         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6077                 err = ext4_setup_system_zone(sb);
6078                 if (err)
6079                         goto restore_opts;
6080         }
6081
6082         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6083                 err = ext4_commit_super(sb);
6084                 if (err)
6085                         goto restore_opts;
6086         }
6087
6088 #ifdef CONFIG_QUOTA
6089         /* Release old quota file names */
6090         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6091                 kfree(old_opts.s_qf_names[i]);
6092         if (enable_quota) {
6093                 if (sb_any_quota_suspended(sb))
6094                         dquot_resume(sb, -1);
6095                 else if (ext4_has_feature_quota(sb)) {
6096                         err = ext4_enable_quotas(sb);
6097                         if (err)
6098                                 goto restore_opts;
6099                 }
6100         }
6101 #endif
6102         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6103                 ext4_release_system_zone(sb);
6104
6105         /*
6106          * Some options can be enabled by ext4 and/or by VFS mount flag
6107          * either way we need to make sure it matches in both *flags and
6108          * s_flags. Copy those selected flags from s_flags to *flags
6109          */
6110         *flags = (*flags & ~vfs_flags) | (sb->s_flags & vfs_flags);
6111
6112         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s. Quota mode: %s.",
6113                  orig_data, ext4_quota_mode(sb));
6114         kfree(orig_data);
6115         return 0;
6116
6117 restore_opts:
6118         sb->s_flags = old_sb_flags;
6119         sbi->s_mount_opt = old_opts.s_mount_opt;
6120         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6121         sbi->s_resuid = old_opts.s_resuid;
6122         sbi->s_resgid = old_opts.s_resgid;
6123         sbi->s_commit_interval = old_opts.s_commit_interval;
6124         sbi->s_min_batch_time = old_opts.s_min_batch_time;
6125         sbi->s_max_batch_time = old_opts.s_max_batch_time;
6126         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6127                 ext4_release_system_zone(sb);
6128 #ifdef CONFIG_QUOTA
6129         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6130         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6131                 to_free[i] = get_qf_name(sb, sbi, i);
6132                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6133         }
6134         synchronize_rcu();
6135         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6136                 kfree(to_free[i]);
6137 #endif
6138         kfree(orig_data);
6139         return err;
6140 }
6141
6142 #ifdef CONFIG_QUOTA
6143 static int ext4_statfs_project(struct super_block *sb,
6144                                kprojid_t projid, struct kstatfs *buf)
6145 {
6146         struct kqid qid;
6147         struct dquot *dquot;
6148         u64 limit;
6149         u64 curblock;
6150
6151         qid = make_kqid_projid(projid);
6152         dquot = dqget(sb, qid);
6153         if (IS_ERR(dquot))
6154                 return PTR_ERR(dquot);
6155         spin_lock(&dquot->dq_dqb_lock);
6156
6157         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6158                              dquot->dq_dqb.dqb_bhardlimit);
6159         limit >>= sb->s_blocksize_bits;
6160
6161         if (limit && buf->f_blocks > limit) {
6162                 curblock = (dquot->dq_dqb.dqb_curspace +
6163                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6164                 buf->f_blocks = limit;
6165                 buf->f_bfree = buf->f_bavail =
6166                         (buf->f_blocks > curblock) ?
6167                          (buf->f_blocks - curblock) : 0;
6168         }
6169
6170         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6171                              dquot->dq_dqb.dqb_ihardlimit);
6172         if (limit && buf->f_files > limit) {
6173                 buf->f_files = limit;
6174                 buf->f_ffree =
6175                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6176                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6177         }
6178
6179         spin_unlock(&dquot->dq_dqb_lock);
6180         dqput(dquot);
6181         return 0;
6182 }
6183 #endif
6184
6185 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6186 {
6187         struct super_block *sb = dentry->d_sb;
6188         struct ext4_sb_info *sbi = EXT4_SB(sb);
6189         struct ext4_super_block *es = sbi->s_es;
6190         ext4_fsblk_t overhead = 0, resv_blocks;
6191         s64 bfree;
6192         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6193
6194         if (!test_opt(sb, MINIX_DF))
6195                 overhead = sbi->s_overhead;
6196
6197         buf->f_type = EXT4_SUPER_MAGIC;
6198         buf->f_bsize = sb->s_blocksize;
6199         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6200         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6201                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6202         /* prevent underflow in case that few free space is available */
6203         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6204         buf->f_bavail = buf->f_bfree -
6205                         (ext4_r_blocks_count(es) + resv_blocks);
6206         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6207                 buf->f_bavail = 0;
6208         buf->f_files = le32_to_cpu(es->s_inodes_count);
6209         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6210         buf->f_namelen = EXT4_NAME_LEN;
6211         buf->f_fsid = uuid_to_fsid(es->s_uuid);
6212
6213 #ifdef CONFIG_QUOTA
6214         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6215             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6216                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6217 #endif
6218         return 0;
6219 }
6220
6221
6222 #ifdef CONFIG_QUOTA
6223
6224 /*
6225  * Helper functions so that transaction is started before we acquire dqio_sem
6226  * to keep correct lock ordering of transaction > dqio_sem
6227  */
6228 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6229 {
6230         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6231 }
6232
6233 static int ext4_write_dquot(struct dquot *dquot)
6234 {
6235         int ret, err;
6236         handle_t *handle;
6237         struct inode *inode;
6238
6239         inode = dquot_to_inode(dquot);
6240         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6241                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6242         if (IS_ERR(handle))
6243                 return PTR_ERR(handle);
6244         ret = dquot_commit(dquot);
6245         err = ext4_journal_stop(handle);
6246         if (!ret)
6247                 ret = err;
6248         return ret;
6249 }
6250
6251 static int ext4_acquire_dquot(struct dquot *dquot)
6252 {
6253         int ret, err;
6254         handle_t *handle;
6255
6256         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6257                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6258         if (IS_ERR(handle))
6259                 return PTR_ERR(handle);
6260         ret = dquot_acquire(dquot);
6261         err = ext4_journal_stop(handle);
6262         if (!ret)
6263                 ret = err;
6264         return ret;
6265 }
6266
6267 static int ext4_release_dquot(struct dquot *dquot)
6268 {
6269         int ret, err;
6270         handle_t *handle;
6271
6272         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6273                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6274         if (IS_ERR(handle)) {
6275                 /* Release dquot anyway to avoid endless cycle in dqput() */
6276                 dquot_release(dquot);
6277                 return PTR_ERR(handle);
6278         }
6279         ret = dquot_release(dquot);
6280         err = ext4_journal_stop(handle);
6281         if (!ret)
6282                 ret = err;
6283         return ret;
6284 }
6285
6286 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6287 {
6288         struct super_block *sb = dquot->dq_sb;
6289
6290         if (ext4_is_quota_journalled(sb)) {
6291                 dquot_mark_dquot_dirty(dquot);
6292                 return ext4_write_dquot(dquot);
6293         } else {
6294                 return dquot_mark_dquot_dirty(dquot);
6295         }
6296 }
6297
6298 static int ext4_write_info(struct super_block *sb, int type)
6299 {
6300         int ret, err;
6301         handle_t *handle;
6302
6303         /* Data block + inode block */
6304         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
6305         if (IS_ERR(handle))
6306                 return PTR_ERR(handle);
6307         ret = dquot_commit_info(sb, type);
6308         err = ext4_journal_stop(handle);
6309         if (!ret)
6310                 ret = err;
6311         return ret;
6312 }
6313
6314 /*
6315  * Turn on quotas during mount time - we need to find
6316  * the quota file and such...
6317  */
6318 static int ext4_quota_on_mount(struct super_block *sb, int type)
6319 {
6320         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
6321                                         EXT4_SB(sb)->s_jquota_fmt, type);
6322 }
6323
6324 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6325 {
6326         struct ext4_inode_info *ei = EXT4_I(inode);
6327
6328         /* The first argument of lockdep_set_subclass has to be
6329          * *exactly* the same as the argument to init_rwsem() --- in
6330          * this case, in init_once() --- or lockdep gets unhappy
6331          * because the name of the lock is set using the
6332          * stringification of the argument to init_rwsem().
6333          */
6334         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6335         lockdep_set_subclass(&ei->i_data_sem, subclass);
6336 }
6337
6338 /*
6339  * Standard function to be called on quota_on
6340  */
6341 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6342                          const struct path *path)
6343 {
6344         int err;
6345
6346         if (!test_opt(sb, QUOTA))
6347                 return -EINVAL;
6348
6349         /* Quotafile not on the same filesystem? */
6350         if (path->dentry->d_sb != sb)
6351                 return -EXDEV;
6352
6353         /* Quota already enabled for this file? */
6354         if (IS_NOQUOTA(d_inode(path->dentry)))
6355                 return -EBUSY;
6356
6357         /* Journaling quota? */
6358         if (EXT4_SB(sb)->s_qf_names[type]) {
6359                 /* Quotafile not in fs root? */
6360                 if (path->dentry->d_parent != sb->s_root)
6361                         ext4_msg(sb, KERN_WARNING,
6362                                 "Quota file not on filesystem root. "
6363                                 "Journaled quota will not work");
6364                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6365         } else {
6366                 /*
6367                  * Clear the flag just in case mount options changed since
6368                  * last time.
6369                  */
6370                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6371         }
6372
6373         /*
6374          * When we journal data on quota file, we have to flush journal to see
6375          * all updates to the file when we bypass pagecache...
6376          */
6377         if (EXT4_SB(sb)->s_journal &&
6378             ext4_should_journal_data(d_inode(path->dentry))) {
6379                 /*
6380                  * We don't need to lock updates but journal_flush() could
6381                  * otherwise be livelocked...
6382                  */
6383                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6384                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
6385                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6386                 if (err)
6387                         return err;
6388         }
6389
6390         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6391         err = dquot_quota_on(sb, type, format_id, path);
6392         if (err) {
6393                 lockdep_set_quota_inode(path->dentry->d_inode,
6394                                              I_DATA_SEM_NORMAL);
6395         } else {
6396                 struct inode *inode = d_inode(path->dentry);
6397                 handle_t *handle;
6398
6399                 /*
6400                  * Set inode flags to prevent userspace from messing with quota
6401                  * files. If this fails, we return success anyway since quotas
6402                  * are already enabled and this is not a hard failure.
6403                  */
6404                 inode_lock(inode);
6405                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6406                 if (IS_ERR(handle))
6407                         goto unlock_inode;
6408                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6409                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6410                                 S_NOATIME | S_IMMUTABLE);
6411                 err = ext4_mark_inode_dirty(handle, inode);
6412                 ext4_journal_stop(handle);
6413         unlock_inode:
6414                 inode_unlock(inode);
6415         }
6416         return err;
6417 }
6418
6419 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6420                              unsigned int flags)
6421 {
6422         int err;
6423         struct inode *qf_inode;
6424         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6425                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6426                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6427                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6428         };
6429
6430         BUG_ON(!ext4_has_feature_quota(sb));
6431
6432         if (!qf_inums[type])
6433                 return -EPERM;
6434
6435         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6436         if (IS_ERR(qf_inode)) {
6437                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6438                 return PTR_ERR(qf_inode);
6439         }
6440
6441         /* Don't account quota for quota files to avoid recursion */
6442         qf_inode->i_flags |= S_NOQUOTA;
6443         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6444         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6445         if (err)
6446                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6447         iput(qf_inode);
6448
6449         return err;
6450 }
6451
6452 /* Enable usage tracking for all quota types. */
6453 static int ext4_enable_quotas(struct super_block *sb)
6454 {
6455         int type, err = 0;
6456         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6457                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6458                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6459                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6460         };
6461         bool quota_mopt[EXT4_MAXQUOTAS] = {
6462                 test_opt(sb, USRQUOTA),
6463                 test_opt(sb, GRPQUOTA),
6464                 test_opt(sb, PRJQUOTA),
6465         };
6466
6467         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6468         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6469                 if (qf_inums[type]) {
6470                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6471                                 DQUOT_USAGE_ENABLED |
6472                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6473                         if (err) {
6474                                 ext4_warning(sb,
6475                                         "Failed to enable quota tracking "
6476                                         "(type=%d, err=%d). Please run "
6477                                         "e2fsck to fix.", type, err);
6478                                 for (type--; type >= 0; type--)
6479                                         dquot_quota_off(sb, type);
6480
6481                                 return err;
6482                         }
6483                 }
6484         }
6485         return 0;
6486 }
6487
6488 static int ext4_quota_off(struct super_block *sb, int type)
6489 {
6490         struct inode *inode = sb_dqopt(sb)->files[type];
6491         handle_t *handle;
6492         int err;
6493
6494         /* Force all delayed allocation blocks to be allocated.
6495          * Caller already holds s_umount sem */
6496         if (test_opt(sb, DELALLOC))
6497                 sync_filesystem(sb);
6498
6499         if (!inode || !igrab(inode))
6500                 goto out;
6501
6502         err = dquot_quota_off(sb, type);
6503         if (err || ext4_has_feature_quota(sb))
6504                 goto out_put;
6505
6506         inode_lock(inode);
6507         /*
6508          * Update modification times of quota files when userspace can
6509          * start looking at them. If we fail, we return success anyway since
6510          * this is not a hard failure and quotas are already disabled.
6511          */
6512         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6513         if (IS_ERR(handle)) {
6514                 err = PTR_ERR(handle);
6515                 goto out_unlock;
6516         }
6517         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6518         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6519         inode->i_mtime = inode->i_ctime = current_time(inode);
6520         err = ext4_mark_inode_dirty(handle, inode);
6521         ext4_journal_stop(handle);
6522 out_unlock:
6523         inode_unlock(inode);
6524 out_put:
6525         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6526         iput(inode);
6527         return err;
6528 out:
6529         return dquot_quota_off(sb, type);
6530 }
6531
6532 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6533  * acquiring the locks... As quota files are never truncated and quota code
6534  * itself serializes the operations (and no one else should touch the files)
6535  * we don't have to be afraid of races */
6536 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6537                                size_t len, loff_t off)
6538 {
6539         struct inode *inode = sb_dqopt(sb)->files[type];
6540         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6541         int offset = off & (sb->s_blocksize - 1);
6542         int tocopy;
6543         size_t toread;
6544         struct buffer_head *bh;
6545         loff_t i_size = i_size_read(inode);
6546
6547         if (off > i_size)
6548                 return 0;
6549         if (off+len > i_size)
6550                 len = i_size-off;
6551         toread = len;
6552         while (toread > 0) {
6553                 tocopy = sb->s_blocksize - offset < toread ?
6554                                 sb->s_blocksize - offset : toread;
6555                 bh = ext4_bread(NULL, inode, blk, 0);
6556                 if (IS_ERR(bh))
6557                         return PTR_ERR(bh);
6558                 if (!bh)        /* A hole? */
6559                         memset(data, 0, tocopy);
6560                 else
6561                         memcpy(data, bh->b_data+offset, tocopy);
6562                 brelse(bh);
6563                 offset = 0;
6564                 toread -= tocopy;
6565                 data += tocopy;
6566                 blk++;
6567         }
6568         return len;
6569 }
6570
6571 /* Write to quotafile (we know the transaction is already started and has
6572  * enough credits) */
6573 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6574                                 const char *data, size_t len, loff_t off)
6575 {
6576         struct inode *inode = sb_dqopt(sb)->files[type];
6577         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6578         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6579         int retries = 0;
6580         struct buffer_head *bh;
6581         handle_t *handle = journal_current_handle();
6582
6583         if (EXT4_SB(sb)->s_journal && !handle) {
6584                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6585                         " cancelled because transaction is not started",
6586                         (unsigned long long)off, (unsigned long long)len);
6587                 return -EIO;
6588         }
6589         /*
6590          * Since we account only one data block in transaction credits,
6591          * then it is impossible to cross a block boundary.
6592          */
6593         if (sb->s_blocksize - offset < len) {
6594                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6595                         " cancelled because not block aligned",
6596                         (unsigned long long)off, (unsigned long long)len);
6597                 return -EIO;
6598         }
6599
6600         do {
6601                 bh = ext4_bread(handle, inode, blk,
6602                                 EXT4_GET_BLOCKS_CREATE |
6603                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6604         } while (PTR_ERR(bh) == -ENOSPC &&
6605                  ext4_should_retry_alloc(inode->i_sb, &retries));
6606         if (IS_ERR(bh))
6607                 return PTR_ERR(bh);
6608         if (!bh)
6609                 goto out;
6610         BUFFER_TRACE(bh, "get write access");
6611         err = ext4_journal_get_write_access(handle, bh);
6612         if (err) {
6613                 brelse(bh);
6614                 return err;
6615         }
6616         lock_buffer(bh);
6617         memcpy(bh->b_data+offset, data, len);
6618         flush_dcache_page(bh->b_page);
6619         unlock_buffer(bh);
6620         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6621         brelse(bh);
6622 out:
6623         if (inode->i_size < off + len) {
6624                 i_size_write(inode, off + len);
6625                 EXT4_I(inode)->i_disksize = inode->i_size;
6626                 err2 = ext4_mark_inode_dirty(handle, inode);
6627                 if (unlikely(err2 && !err))
6628                         err = err2;
6629         }
6630         return err ? err : len;
6631 }
6632 #endif
6633
6634 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6635                        const char *dev_name, void *data)
6636 {
6637         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6638 }
6639
6640 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6641 static inline void register_as_ext2(void)
6642 {
6643         int err = register_filesystem(&ext2_fs_type);
6644         if (err)
6645                 printk(KERN_WARNING
6646                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6647 }
6648
6649 static inline void unregister_as_ext2(void)
6650 {
6651         unregister_filesystem(&ext2_fs_type);
6652 }
6653
6654 static inline int ext2_feature_set_ok(struct super_block *sb)
6655 {
6656         if (ext4_has_unknown_ext2_incompat_features(sb))
6657                 return 0;
6658         if (sb_rdonly(sb))
6659                 return 1;
6660         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6661                 return 0;
6662         return 1;
6663 }
6664 #else
6665 static inline void register_as_ext2(void) { }
6666 static inline void unregister_as_ext2(void) { }
6667 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6668 #endif
6669
6670 static inline void register_as_ext3(void)
6671 {
6672         int err = register_filesystem(&ext3_fs_type);
6673         if (err)
6674                 printk(KERN_WARNING
6675                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6676 }
6677
6678 static inline void unregister_as_ext3(void)
6679 {
6680         unregister_filesystem(&ext3_fs_type);
6681 }
6682
6683 static inline int ext3_feature_set_ok(struct super_block *sb)
6684 {
6685         if (ext4_has_unknown_ext3_incompat_features(sb))
6686                 return 0;
6687         if (!ext4_has_feature_journal(sb))
6688                 return 0;
6689         if (sb_rdonly(sb))
6690                 return 1;
6691         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6692                 return 0;
6693         return 1;
6694 }
6695
6696 static struct file_system_type ext4_fs_type = {
6697         .owner          = THIS_MODULE,
6698         .name           = "ext4",
6699         .mount          = ext4_mount,
6700         .kill_sb        = kill_block_super,
6701         .fs_flags       = FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
6702 };
6703 MODULE_ALIAS_FS("ext4");
6704
6705 /* Shared across all ext4 file systems */
6706 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6707
6708 static int __init ext4_init_fs(void)
6709 {
6710         int i, err;
6711
6712         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6713         ext4_li_info = NULL;
6714
6715         /* Build-time check for flags consistency */
6716         ext4_check_flag_values();
6717
6718         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6719                 init_waitqueue_head(&ext4__ioend_wq[i]);
6720
6721         err = ext4_init_es();
6722         if (err)
6723                 return err;
6724
6725         err = ext4_init_pending();
6726         if (err)
6727                 goto out7;
6728
6729         err = ext4_init_post_read_processing();
6730         if (err)
6731                 goto out6;
6732
6733         err = ext4_init_pageio();
6734         if (err)
6735                 goto out5;
6736
6737         err = ext4_init_system_zone();
6738         if (err)
6739                 goto out4;
6740
6741         err = ext4_init_sysfs();
6742         if (err)
6743                 goto out3;
6744
6745         err = ext4_init_mballoc();
6746         if (err)
6747                 goto out2;
6748         err = init_inodecache();
6749         if (err)
6750                 goto out1;
6751
6752         err = ext4_fc_init_dentry_cache();
6753         if (err)
6754                 goto out05;
6755
6756         register_as_ext3();
6757         register_as_ext2();
6758         err = register_filesystem(&ext4_fs_type);
6759         if (err)
6760                 goto out;
6761
6762         return 0;
6763 out:
6764         unregister_as_ext2();
6765         unregister_as_ext3();
6766 out05:
6767         destroy_inodecache();
6768 out1:
6769         ext4_exit_mballoc();
6770 out2:
6771         ext4_exit_sysfs();
6772 out3:
6773         ext4_exit_system_zone();
6774 out4:
6775         ext4_exit_pageio();
6776 out5:
6777         ext4_exit_post_read_processing();
6778 out6:
6779         ext4_exit_pending();
6780 out7:
6781         ext4_exit_es();
6782
6783         return err;
6784 }
6785
6786 static void __exit ext4_exit_fs(void)
6787 {
6788         ext4_destroy_lazyinit_thread();
6789         unregister_as_ext2();
6790         unregister_as_ext3();
6791         unregister_filesystem(&ext4_fs_type);
6792         destroy_inodecache();
6793         ext4_exit_mballoc();
6794         ext4_exit_sysfs();
6795         ext4_exit_system_zone();
6796         ext4_exit_pageio();
6797         ext4_exit_post_read_processing();
6798         ext4_exit_es();
6799         ext4_exit_pending();
6800 }
6801
6802 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6803 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6804 MODULE_LICENSE("GPL");
6805 MODULE_SOFTDEP("pre: crc32c");
6806 module_init(ext4_init_fs)
6807 module_exit(ext4_exit_fs)