ext4/super.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/ext4/super.c
   4  *
   5  * Copyright (C) 1992, 1993, 1994, 1995
   6  * Remy Card (card@masi.ibp.fr)
   7  * Laboratoire MASI - Institut Blaise Pascal
   8  * Universite Pierre et Marie Curie (Paris VI)
   9  *
  10  *  from
  11  *
  12  *  linux/fs/minix/inode.c
  13  *
  14  *  Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  *  Big-endian to little-endian byte-swapping/bitmaps by
  17  *        David S. Miller (davem@caip.rutgers.edu), 1995
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/string.h>
  22 #include <linux/fs.h>
  23 #include <linux/time.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/backing-dev.h>
  29 #include <linux/parser.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/dax.h>
  42 #include <linux/cleancache.h>
  43 #include <linux/uaccess.h>
  44 #include <linux/iversion.h>
  45 #include <linux/unicode.h>
  46 #include <linux/part_stat.h>
  47 #include <linux/kthread.h>
  48 #include <linux/freezer.h>
  49
  50 #include "ext4.h"
  51 #include "ext4_extents.h"       /* Needed for trace points definition */
  52 #include "ext4_jbd2.h"
  53 #include "xattr.h"
  54 #include "acl.h"
  55 #include "mballoc.h"
  56 #include "fsmap.h"
  57
  58 #define CREATE_TRACE_POINTS
  59 #include <trace/events/ext4.h>
  60
  61 static struct ext4_lazy_init *ext4_li_info;
  62 static 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                 struct buffer_head *sbh = sbi->s_sbh;
 709                 handle = jbd2_journal_start(journal, 1);
 710                 if (IS_ERR(handle))
 711                         goto write_directly;
 712                 if (jbd2_journal_get_write_access(handle, sbh)) {
 713                         jbd2_journal_stop(handle);
 714                         goto write_directly;
 715                 }
 716                 ext4_update_super(sbi->s_sb);
 717                 if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
 718                         ext4_msg(sbi->s_sb, KERN_ERR, "previous I/O error to "
 719                                  "superblock detected");
 720                         clear_buffer_write_io_error(sbh);
 721                         set_buffer_uptodate(sbh);
 722                 }
 723
 724                 if (jbd2_journal_dirty_metadata(handle, sbh)) {
 725                         jbd2_journal_stop(handle);
 726                         goto write_directly;
 727                 }
 728                 jbd2_journal_stop(handle);
 729                 return;
 730         }
 731 write_directly:
 732         /*
 733          * Write through journal failed. Write sb directly to get error info
 734          * out and hope for the best.
 735          */
 736         ext4_commit_super(sbi->s_sb);
 737 }
 738
 739 #define ext4_error_ratelimit(sb)                                        \
 740                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 741                              "EXT4-fs error")
 742
 743 void __ext4_error(struct super_block *sb, const char *function,
 744                   unsigned int line, bool force_ro, int error, __u64 block,
 745                   const char *fmt, ...)
 746 {
 747         struct va_format vaf;
 748         va_list args;
 749
 750         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 751                 return;
 752
 753         trace_ext4_error(sb, function, line);
 754         if (ext4_error_ratelimit(sb)) {
 755                 va_start(args, fmt);
 756                 vaf.fmt = fmt;
 757                 vaf.va = &args;
 758                 printk(KERN_CRIT
 759                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 760                        sb->s_id, function, line, current->comm, &vaf);
 761                 va_end(args);
 762         }
 763         ext4_handle_error(sb, force_ro, error, 0, block, function, line);
 764 }
 765
 766 void __ext4_error_inode(struct inode *inode, const char *function,
 767                         unsigned int line, ext4_fsblk_t block, int error,
 768                         const char *fmt, ...)
 769 {
 770         va_list args;
 771         struct va_format vaf;
 772
 773         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 774                 return;
 775
 776         trace_ext4_error(inode->i_sb, function, line);
 777         if (ext4_error_ratelimit(inode->i_sb)) {
 778                 va_start(args, fmt);
 779                 vaf.fmt = fmt;
 780                 vaf.va = &args;
 781                 if (block)
 782                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 783                                "inode #%lu: block %llu: comm %s: %pV\n",
 784                                inode->i_sb->s_id, function, line, inode->i_ino,
 785                                block, current->comm, &vaf);
 786                 else
 787                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 788                                "inode #%lu: comm %s: %pV\n",
 789                                inode->i_sb->s_id, function, line, inode->i_ino,
 790                                current->comm, &vaf);
 791                 va_end(args);
 792         }
 793         ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
 794                           function, line);
 795 }
 796
 797 void __ext4_error_file(struct file *file, const char *function,
 798                        unsigned int line, ext4_fsblk_t block,
 799                        const char *fmt, ...)
 800 {
 801         va_list args;
 802         struct va_format vaf;
 803         struct inode *inode = file_inode(file);
 804         char pathname[80], *path;
 805
 806         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 807                 return;
 808
 809         trace_ext4_error(inode->i_sb, function, line);
 810         if (ext4_error_ratelimit(inode->i_sb)) {
 811                 path = file_path(file, pathname, sizeof(pathname));
 812                 if (IS_ERR(path))
 813                         path = "(unknown)";
 814                 va_start(args, fmt);
 815                 vaf.fmt = fmt;
 816                 vaf.va = &args;
 817                 if (block)
 818                         printk(KERN_CRIT
 819                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 820                                "block %llu: comm %s: path %s: %pV\n",
 821                                inode->i_sb->s_id, function, line, inode->i_ino,
 822                                block, current->comm, path, &vaf);
 823                 else
 824                         printk(KERN_CRIT
 825                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 826                                "comm %s: path %s: %pV\n",
 827                                inode->i_sb->s_id, function, line, inode->i_ino,
 828                                current->comm, path, &vaf);
 829                 va_end(args);
 830         }
 831         ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
 832                           function, line);
 833 }
 834
 835 const char *ext4_decode_error(struct super_block *sb, int errno,
 836                               char nbuf[16])
 837 {
 838         char *errstr = NULL;
 839
 840         switch (errno) {
 841         case -EFSCORRUPTED:
 842                 errstr = "Corrupt filesystem";
 843                 break;
 844         case -EFSBADCRC:
 845                 errstr = "Filesystem failed CRC";
 846                 break;
 847         case -EIO:
 848                 errstr = "IO failure";
 849                 break;
 850         case -ENOMEM:
 851                 errstr = "Out of memory";
 852                 break;
 853         case -EROFS:
 854                 if (!sb || (EXT4_SB(sb)->s_journal &&
 855                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 856                         errstr = "Journal has aborted";
 857                 else
 858                         errstr = "Readonly filesystem";
 859                 break;
 860         default:
 861                 /* If the caller passed in an extra buffer for unknown
 862                  * errors, textualise them now.  Else we just return
 863                  * NULL. */
 864                 if (nbuf) {
 865                         /* Check for truncated error codes... */
 866                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 867                                 errstr = nbuf;
 868                 }
 869                 break;
 870         }
 871
 872         return errstr;
 873 }
 874
 875 /* __ext4_std_error decodes expected errors from journaling functions
 876  * automatically and invokes the appropriate error response.  */
 877
 878 void __ext4_std_error(struct super_block *sb, const char *function,
 879                       unsigned int line, int errno)
 880 {
 881         char nbuf[16];
 882         const char *errstr;
 883
 884         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 885                 return;
 886
 887         /* Special case: if the error is EROFS, and we're not already
 888          * inside a transaction, then there's really no point in logging
 889          * an error. */
 890         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 891                 return;
 892
 893         if (ext4_error_ratelimit(sb)) {
 894                 errstr = ext4_decode_error(sb, errno, nbuf);
 895                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 896                        sb->s_id, function, line, errstr);
 897         }
 898
 899         ext4_handle_error(sb, false, -errno, 0, 0, function, line);
 900 }
 901
 902 void __ext4_msg(struct super_block *sb,
 903                 const char *prefix, const char *fmt, ...)
 904 {
 905         struct va_format vaf;
 906         va_list args;
 907
 908         atomic_inc(&EXT4_SB(sb)->s_msg_count);
 909         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 910                 return;
 911
 912         va_start(args, fmt);
 913         vaf.fmt = fmt;
 914         vaf.va = &args;
 915         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 916         va_end(args);
 917 }
 918
 919 static int ext4_warning_ratelimit(struct super_block *sb)
 920 {
 921         atomic_inc(&EXT4_SB(sb)->s_warning_count);
 922         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
 923                             "EXT4-fs warning");
 924 }
 925
 926 void __ext4_warning(struct super_block *sb, const char *function,
 927                     unsigned int line, const char *fmt, ...)
 928 {
 929         struct va_format vaf;
 930         va_list args;
 931
 932         if (!ext4_warning_ratelimit(sb))
 933                 return;
 934
 935         va_start(args, fmt);
 936         vaf.fmt = fmt;
 937         vaf.va = &args;
 938         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 939                sb->s_id, function, line, &vaf);
 940         va_end(args);
 941 }
 942
 943 void __ext4_warning_inode(const struct inode *inode, const char *function,
 944                           unsigned int line, const char *fmt, ...)
 945 {
 946         struct va_format vaf;
 947         va_list args;
 948
 949         if (!ext4_warning_ratelimit(inode->i_sb))
 950                 return;
 951
 952         va_start(args, fmt);
 953         vaf.fmt = fmt;
 954         vaf.va = &args;
 955         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 956                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 957                function, line, inode->i_ino, current->comm, &vaf);
 958         va_end(args);
 959 }
 960
 961 void __ext4_grp_locked_error(const char *function, unsigned int line,
 962                              struct super_block *sb, ext4_group_t grp,
 963                              unsigned long ino, ext4_fsblk_t block,
 964                              const char *fmt, ...)
 965 __releases(bitlock)
 966 __acquires(bitlock)
 967 {
 968         struct va_format vaf;
 969         va_list args;
 970
 971         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 972                 return;
 973
 974         trace_ext4_error(sb, function, line);
 975         if (ext4_error_ratelimit(sb)) {
 976                 va_start(args, fmt);
 977                 vaf.fmt = fmt;
 978                 vaf.va = &args;
 979                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 980                        sb->s_id, function, line, grp);
 981                 if (ino)
 982                         printk(KERN_CONT "inode %lu: ", ino);
 983                 if (block)
 984                         printk(KERN_CONT "block %llu:",
 985                                (unsigned long long) block);
 986                 printk(KERN_CONT "%pV\n", &vaf);
 987                 va_end(args);
 988         }
 989
 990         if (test_opt(sb, ERRORS_CONT)) {
 991                 if (test_opt(sb, WARN_ON_ERROR))
 992                         WARN_ON_ONCE(1);
 993                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 994                 if (!bdev_read_only(sb->s_bdev)) {
 995                         save_error_info(sb, EFSCORRUPTED, ino, block, function,
 996                                         line);
 997                         schedule_work(&EXT4_SB(sb)->s_error_work);
 998                 }
 999                 return;
1000         }
1001         ext4_unlock_group(sb, grp);
1002         ext4_handle_error(sb, false, EFSCORRUPTED, ino, block, function, line);
1003         /*
1004          * We only get here in the ERRORS_RO case; relocking the group
1005          * may be dangerous, but nothing bad will happen since the
1006          * filesystem will have already been marked read/only and the
1007          * journal has been aborted.  We return 1 as a hint to callers
1008          * who might what to use the return value from
1009          * ext4_grp_locked_error() to distinguish between the
1010          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1011          * aggressively from the ext4 function in question, with a
1012          * more appropriate error code.
1013          */
1014         ext4_lock_group(sb, grp);
1015         return;
1016 }
1017
1018 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1019                                      ext4_group_t group,
1020                                      unsigned int flags)
1021 {
1022         struct ext4_sb_info *sbi = EXT4_SB(sb);
1023         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1024         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1025         int ret;
1026
1027         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1028                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1029                                             &grp->bb_state);
1030                 if (!ret)
1031                         percpu_counter_sub(&sbi->s_freeclusters_counter,
1032                                            grp->bb_free);
1033         }
1034
1035         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1036                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1037                                             &grp->bb_state);
1038                 if (!ret && gdp) {
1039                         int count;
1040
1041                         count = ext4_free_inodes_count(sb, gdp);
1042                         percpu_counter_sub(&sbi->s_freeinodes_counter,
1043                                            count);
1044                 }
1045         }
1046 }
1047
1048 void ext4_update_dynamic_rev(struct super_block *sb)
1049 {
1050         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1051
1052         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1053                 return;
1054
1055         ext4_warning(sb,
1056                      "updating to rev %d because of new feature flag, "
1057                      "running e2fsck is recommended",
1058                      EXT4_DYNAMIC_REV);
1059
1060         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1061         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1062         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1063         /* leave es->s_feature_*compat flags alone */
1064         /* es->s_uuid will be set by e2fsck if empty */
1065
1066         /*
1067          * The rest of the superblock fields should be zero, and if not it
1068          * means they are likely already in use, so leave them alone.  We
1069          * can leave it up to e2fsck to clean up any inconsistencies there.
1070          */
1071 }
1072
1073 /*
1074  * Open the external journal device
1075  */
1076 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
1077 {
1078         struct block_device *bdev;
1079
1080         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
1081         if (IS_ERR(bdev))
1082                 goto fail;
1083         return bdev;
1084
1085 fail:
1086         ext4_msg(sb, KERN_ERR,
1087                  "failed to open journal device unknown-block(%u,%u) %ld",
1088                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
1089         return NULL;
1090 }
1091
1092 /*
1093  * Release the journal device
1094  */
1095 static void ext4_blkdev_put(struct block_device *bdev)
1096 {
1097         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1098 }
1099
1100 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
1101 {
1102         struct block_device *bdev;
1103         bdev = sbi->s_journal_bdev;
1104         if (bdev) {
1105                 ext4_blkdev_put(bdev);
1106                 sbi->s_journal_bdev = NULL;
1107         }
1108 }
1109
1110 static inline struct inode *orphan_list_entry(struct list_head *l)
1111 {
1112         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1113 }
1114
1115 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1116 {
1117         struct list_head *l;
1118
1119         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1120                  le32_to_cpu(sbi->s_es->s_last_orphan));
1121
1122         printk(KERN_ERR "sb_info orphan list:\n");
1123         list_for_each(l, &sbi->s_orphan) {
1124                 struct inode *inode = orphan_list_entry(l);
1125                 printk(KERN_ERR "  "
1126                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1127                        inode->i_sb->s_id, inode->i_ino, inode,
1128                        inode->i_mode, inode->i_nlink,
1129                        NEXT_ORPHAN(inode));
1130         }
1131 }
1132
1133 #ifdef CONFIG_QUOTA
1134 static int ext4_quota_off(struct super_block *sb, int type);
1135
1136 static inline void ext4_quota_off_umount(struct super_block *sb)
1137 {
1138         int type;
1139
1140         /* Use our quota_off function to clear inode flags etc. */
1141         for (type = 0; type < EXT4_MAXQUOTAS; type++)
1142                 ext4_quota_off(sb, type);
1143 }
1144
1145 /*
1146  * This is a helper function which is used in the mount/remount
1147  * codepaths (which holds s_umount) to fetch the quota file name.
1148  */
1149 static inline char *get_qf_name(struct super_block *sb,
1150                                 struct ext4_sb_info *sbi,
1151                                 int type)
1152 {
1153         return rcu_dereference_protected(sbi->s_qf_names[type],
1154                                          lockdep_is_held(&sb->s_umount));
1155 }
1156 #else
1157 static inline void ext4_quota_off_umount(struct super_block *sb)
1158 {
1159 }
1160 #endif
1161
1162 static void ext4_put_super(struct super_block *sb)
1163 {
1164         struct ext4_sb_info *sbi = EXT4_SB(sb);
1165         struct ext4_super_block *es = sbi->s_es;
1166         struct buffer_head **group_desc;
1167         struct flex_groups **flex_groups;
1168         int aborted = 0;
1169         int i, err;
1170
1171         ext4_unregister_li_request(sb);
1172         ext4_quota_off_umount(sb);
1173
1174         flush_work(&sbi->s_error_work);
1175         destroy_workqueue(sbi->rsv_conversion_wq);
1176
1177         /*
1178          * Unregister sysfs before destroying jbd2 journal.
1179          * Since we could still access attr_journal_task attribute via sysfs
1180          * path which could have sbi->s_journal->j_task as NULL
1181          */
1182         ext4_unregister_sysfs(sb);
1183
1184         if (sbi->s_journal) {
1185                 aborted = is_journal_aborted(sbi->s_journal);
1186                 err = jbd2_journal_destroy(sbi->s_journal);
1187                 sbi->s_journal = NULL;
1188                 if ((err < 0) && !aborted) {
1189                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1190                 }
1191         }
1192
1193         ext4_es_unregister_shrinker(sbi);
1194         del_timer_sync(&sbi->s_err_report);
1195         ext4_release_system_zone(sb);
1196         ext4_mb_release(sb);
1197         ext4_ext_release(sb);
1198
1199         if (!sb_rdonly(sb) && !aborted) {
1200                 ext4_clear_feature_journal_needs_recovery(sb);
1201                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1202         }
1203         if (!sb_rdonly(sb))
1204                 ext4_commit_super(sb);
1205
1206         rcu_read_lock();
1207         group_desc = rcu_dereference(sbi->s_group_desc);
1208         for (i = 0; i < sbi->s_gdb_count; i++)
1209                 brelse(group_desc[i]);
1210         kvfree(group_desc);
1211         flex_groups = rcu_dereference(sbi->s_flex_groups);
1212         if (flex_groups) {
1213                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1214                         kvfree(flex_groups[i]);
1215                 kvfree(flex_groups);
1216         }
1217         rcu_read_unlock();
1218         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1219         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1220         percpu_counter_destroy(&sbi->s_dirs_counter);
1221         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1222         percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
1223         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1224 #ifdef CONFIG_QUOTA
1225         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1226                 kfree(get_qf_name(sb, sbi, i));
1227 #endif
1228
1229         /* Debugging code just in case the in-memory inode orphan list
1230          * isn't empty.  The on-disk one can be non-empty if we've
1231          * detected an error and taken the fs readonly, but the
1232          * in-memory list had better be clean by this point. */
1233         if (!list_empty(&sbi->s_orphan))
1234                 dump_orphan_list(sb, sbi);
1235         ASSERT(list_empty(&sbi->s_orphan));
1236
1237         sync_blockdev(sb->s_bdev);
1238         invalidate_bdev(sb->s_bdev);
1239         if (sbi->s_journal_bdev && sbi->s_journal_bdev != sb->s_bdev) {
1240                 /*
1241                  * Invalidate the journal device's buffers.  We don't want them
1242                  * floating about in memory - the physical journal device may
1243                  * hotswapped, and it breaks the `ro-after' testing code.
1244                  */
1245                 sync_blockdev(sbi->s_journal_bdev);
1246                 invalidate_bdev(sbi->s_journal_bdev);
1247                 ext4_blkdev_remove(sbi);
1248         }
1249
1250         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1251         sbi->s_ea_inode_cache = NULL;
1252
1253         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1254         sbi->s_ea_block_cache = NULL;
1255
1256         ext4_stop_mmpd(sbi);
1257
1258         brelse(sbi->s_sbh);
1259         sb->s_fs_info = NULL;
1260         /*
1261          * Now that we are completely done shutting down the
1262          * superblock, we need to actually destroy the kobject.
1263          */
1264         kobject_put(&sbi->s_kobj);
1265         wait_for_completion(&sbi->s_kobj_unregister);
1266         if (sbi->s_chksum_driver)
1267                 crypto_free_shash(sbi->s_chksum_driver);
1268         kfree(sbi->s_blockgroup_lock);
1269         fs_put_dax(sbi->s_daxdev);
1270         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1271 #ifdef CONFIG_UNICODE
1272         utf8_unload(sb->s_encoding);
1273 #endif
1274         kfree(sbi);
1275 }
1276
1277 static struct kmem_cache *ext4_inode_cachep;
1278
1279 /*
1280  * Called inside transaction, so use GFP_NOFS
1281  */
1282 static struct inode *ext4_alloc_inode(struct super_block *sb)
1283 {
1284         struct ext4_inode_info *ei;
1285
1286         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1287         if (!ei)
1288                 return NULL;
1289
1290         inode_set_iversion(&ei->vfs_inode, 1);
1291         spin_lock_init(&ei->i_raw_lock);
1292         INIT_LIST_HEAD(&ei->i_prealloc_list);
1293         atomic_set(&ei->i_prealloc_active, 0);
1294         spin_lock_init(&ei->i_prealloc_lock);
1295         ext4_es_init_tree(&ei->i_es_tree);
1296         rwlock_init(&ei->i_es_lock);
1297         INIT_LIST_HEAD(&ei->i_es_list);
1298         ei->i_es_all_nr = 0;
1299         ei->i_es_shk_nr = 0;
1300         ei->i_es_shrink_lblk = 0;
1301         ei->i_reserved_data_blocks = 0;
1302         spin_lock_init(&(ei->i_block_reservation_lock));
1303         ext4_init_pending_tree(&ei->i_pending_tree);
1304 #ifdef CONFIG_QUOTA
1305         ei->i_reserved_quota = 0;
1306         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1307 #endif
1308         ei->jinode = NULL;
1309         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1310         spin_lock_init(&ei->i_completed_io_lock);
1311         ei->i_sync_tid = 0;
1312         ei->i_datasync_tid = 0;
1313         atomic_set(&ei->i_unwritten, 0);
1314         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1315         ext4_fc_init_inode(&ei->vfs_inode);
1316         mutex_init(&ei->i_fc_lock);
1317         return &ei->vfs_inode;
1318 }
1319
1320 static int ext4_drop_inode(struct inode *inode)
1321 {
1322         int drop = generic_drop_inode(inode);
1323
1324         if (!drop)
1325                 drop = fscrypt_drop_inode(inode);
1326
1327         trace_ext4_drop_inode(inode, drop);
1328         return drop;
1329 }
1330
1331 static void ext4_free_in_core_inode(struct inode *inode)
1332 {
1333         fscrypt_free_inode(inode);
1334         if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1335                 pr_warn("%s: inode %ld still in fc list",
1336                         __func__, inode->i_ino);
1337         }
1338         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1339 }
1340
1341 static void ext4_destroy_inode(struct inode *inode)
1342 {
1343         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1344                 ext4_msg(inode->i_sb, KERN_ERR,
1345                          "Inode %lu (%p): orphan list check failed!",
1346                          inode->i_ino, EXT4_I(inode));
1347                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1348                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1349                                 true);
1350                 dump_stack();
1351         }
1352 }
1353
1354 static void init_once(void *foo)
1355 {
1356         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1357
1358         INIT_LIST_HEAD(&ei->i_orphan);
1359         init_rwsem(&ei->xattr_sem);
1360         init_rwsem(&ei->i_data_sem);
1361         init_rwsem(&ei->i_mmap_sem);
1362         inode_init_once(&ei->vfs_inode);
1363         ext4_fc_init_inode(&ei->vfs_inode);
1364 }
1365
1366 static int __init init_inodecache(void)
1367 {
1368         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1369                                 sizeof(struct ext4_inode_info), 0,
1370                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1371                                         SLAB_ACCOUNT),
1372                                 offsetof(struct ext4_inode_info, i_data),
1373                                 sizeof_field(struct ext4_inode_info, i_data),
1374                                 init_once);
1375         if (ext4_inode_cachep == NULL)
1376                 return -ENOMEM;
1377         return 0;
1378 }
1379
1380 static void destroy_inodecache(void)
1381 {
1382         /*
1383          * Make sure all delayed rcu free inodes are flushed before we
1384          * destroy cache.
1385          */
1386         rcu_barrier();
1387         kmem_cache_destroy(ext4_inode_cachep);
1388 }
1389
1390 void ext4_clear_inode(struct inode *inode)
1391 {
1392         ext4_fc_del(inode);
1393         invalidate_inode_buffers(inode);
1394         clear_inode(inode);
1395         ext4_discard_preallocations(inode, 0);
1396         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1397         dquot_drop(inode);
1398         if (EXT4_I(inode)->jinode) {
1399                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1400                                                EXT4_I(inode)->jinode);
1401                 jbd2_free_inode(EXT4_I(inode)->jinode);
1402                 EXT4_I(inode)->jinode = NULL;
1403         }
1404         fscrypt_put_encryption_info(inode);
1405         fsverity_cleanup_inode(inode);
1406 }
1407
1408 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1409                                         u64 ino, u32 generation)
1410 {
1411         struct inode *inode;
1412
1413         /*
1414          * Currently we don't know the generation for parent directory, so
1415          * a generation of 0 means "accept any"
1416          */
1417         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1418         if (IS_ERR(inode))
1419                 return ERR_CAST(inode);
1420         if (generation && inode->i_generation != generation) {
1421                 iput(inode);
1422                 return ERR_PTR(-ESTALE);
1423         }
1424
1425         return inode;
1426 }
1427
1428 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1429                                         int fh_len, int fh_type)
1430 {
1431         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1432                                     ext4_nfs_get_inode);
1433 }
1434
1435 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1436                                         int fh_len, int fh_type)
1437 {
1438         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1439                                     ext4_nfs_get_inode);
1440 }
1441
1442 static int ext4_nfs_commit_metadata(struct inode *inode)
1443 {
1444         struct writeback_control wbc = {
1445                 .sync_mode = WB_SYNC_ALL
1446         };
1447
1448         trace_ext4_nfs_commit_metadata(inode);
1449         return ext4_write_inode(inode, &wbc);
1450 }
1451
1452 /*
1453  * Try to release metadata pages (indirect blocks, directories) which are
1454  * mapped via the block device.  Since these pages could have journal heads
1455  * which would prevent try_to_free_buffers() from freeing them, we must use
1456  * jbd2 layer's try_to_free_buffers() function to release them.
1457  */
1458 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1459                                  gfp_t wait)
1460 {
1461         journal_t *journal = EXT4_SB(sb)->s_journal;
1462
1463         WARN_ON(PageChecked(page));
1464         if (!page_has_buffers(page))
1465                 return 0;
1466         if (journal)
1467                 return jbd2_journal_try_to_free_buffers(journal, page);
1468
1469         return try_to_free_buffers(page);
1470 }
1471
1472 #ifdef CONFIG_FS_ENCRYPTION
1473 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1474 {
1475         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1476                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1477 }
1478
1479 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1480                                                         void *fs_data)
1481 {
1482         handle_t *handle = fs_data;
1483         int res, res2, credits, retries = 0;
1484
1485         /*
1486          * Encrypting the root directory is not allowed because e2fsck expects
1487          * lost+found to exist and be unencrypted, and encrypting the root
1488          * directory would imply encrypting the lost+found directory as well as
1489          * the filename "lost+found" itself.
1490          */
1491         if (inode->i_ino == EXT4_ROOT_INO)
1492                 return -EPERM;
1493
1494         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1495                 return -EINVAL;
1496
1497         if (ext4_test_inode_flag(inode, EXT4_INODE_DAX))
1498                 return -EOPNOTSUPP;
1499
1500         res = ext4_convert_inline_data(inode);
1501         if (res)
1502                 return res;
1503
1504         /*
1505          * If a journal handle was specified, then the encryption context is
1506          * being set on a new inode via inheritance and is part of a larger
1507          * transaction to create the inode.  Otherwise the encryption context is
1508          * being set on an existing inode in its own transaction.  Only in the
1509          * latter case should the "retry on ENOSPC" logic be used.
1510          */
1511
1512         if (handle) {
1513                 res = ext4_xattr_set_handle(handle, inode,
1514                                             EXT4_XATTR_INDEX_ENCRYPTION,
1515                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1516                                             ctx, len, 0);
1517                 if (!res) {
1518                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1519                         ext4_clear_inode_state(inode,
1520                                         EXT4_STATE_MAY_INLINE_DATA);
1521                         /*
1522                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1523                          * S_DAX may be disabled
1524                          */
1525                         ext4_set_inode_flags(inode, false);
1526                 }
1527                 return res;
1528         }
1529
1530         res = dquot_initialize(inode);
1531         if (res)
1532                 return res;
1533 retry:
1534         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1535                                      &credits);
1536         if (res)
1537                 return res;
1538
1539         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1540         if (IS_ERR(handle))
1541                 return PTR_ERR(handle);
1542
1543         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1544                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1545                                     ctx, len, 0);
1546         if (!res) {
1547                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1548                 /*
1549                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1550                  * S_DAX may be disabled
1551                  */
1552                 ext4_set_inode_flags(inode, false);
1553                 res = ext4_mark_inode_dirty(handle, inode);
1554                 if (res)
1555                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1556         }
1557         res2 = ext4_journal_stop(handle);
1558
1559         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1560                 goto retry;
1561         if (!res)
1562                 res = res2;
1563         return res;
1564 }
1565
1566 static const union fscrypt_policy *ext4_get_dummy_policy(struct super_block *sb)
1567 {
1568         return EXT4_SB(sb)->s_dummy_enc_policy.policy;
1569 }
1570
1571 static bool ext4_has_stable_inodes(struct super_block *sb)
1572 {
1573         return ext4_has_feature_stable_inodes(sb);
1574 }
1575
1576 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1577                                        int *ino_bits_ret, int *lblk_bits_ret)
1578 {
1579         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1580         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1581 }
1582
1583 static const struct fscrypt_operations ext4_cryptops = {
1584         .key_prefix             = "ext4:",
1585         .get_context            = ext4_get_context,
1586         .set_context            = ext4_set_context,
1587         .get_dummy_policy       = ext4_get_dummy_policy,
1588         .empty_dir              = ext4_empty_dir,
1589         .max_namelen            = EXT4_NAME_LEN,
1590         .has_stable_inodes      = ext4_has_stable_inodes,
1591         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1592 };
1593 #endif
1594
1595 #ifdef CONFIG_QUOTA
1596 static const char * const quotatypes[] = INITQFNAMES;
1597 #define QTYPE2NAME(t) (quotatypes[t])
1598
1599 static int ext4_write_dquot(struct dquot *dquot);
1600 static int ext4_acquire_dquot(struct dquot *dquot);
1601 static int ext4_release_dquot(struct dquot *dquot);
1602 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1603 static int ext4_write_info(struct super_block *sb, int type);
1604 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1605                          const struct path *path);
1606 static int ext4_quota_on_mount(struct super_block *sb, int type);
1607 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1608                                size_t len, loff_t off);
1609 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1610                                 const char *data, size_t len, loff_t off);
1611 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1612                              unsigned int flags);
1613 static int ext4_enable_quotas(struct super_block *sb);
1614
1615 static struct dquot **ext4_get_dquots(struct inode *inode)
1616 {
1617         return EXT4_I(inode)->i_dquot;
1618 }
1619
1620 static const struct dquot_operations ext4_quota_operations = {
1621         .get_reserved_space     = ext4_get_reserved_space,
1622         .write_dquot            = ext4_write_dquot,
1623         .acquire_dquot          = ext4_acquire_dquot,
1624         .release_dquot          = ext4_release_dquot,
1625         .mark_dirty             = ext4_mark_dquot_dirty,
1626         .write_info             = ext4_write_info,
1627         .alloc_dquot            = dquot_alloc,
1628         .destroy_dquot          = dquot_destroy,
1629         .get_projid             = ext4_get_projid,
1630         .get_inode_usage        = ext4_get_inode_usage,
1631         .get_next_id            = dquot_get_next_id,
1632 };
1633
1634 static const struct quotactl_ops ext4_qctl_operations = {
1635         .quota_on       = ext4_quota_on,
1636         .quota_off      = ext4_quota_off,
1637         .quota_sync     = dquot_quota_sync,
1638         .get_state      = dquot_get_state,
1639         .set_info       = dquot_set_dqinfo,
1640         .get_dqblk      = dquot_get_dqblk,
1641         .set_dqblk      = dquot_set_dqblk,
1642         .get_nextdqblk  = dquot_get_next_dqblk,
1643 };
1644 #endif
1645
1646 static const struct super_operations ext4_sops = {
1647         .alloc_inode    = ext4_alloc_inode,
1648         .free_inode     = ext4_free_in_core_inode,
1649         .destroy_inode  = ext4_destroy_inode,
1650         .write_inode    = ext4_write_inode,
1651         .dirty_inode    = ext4_dirty_inode,
1652         .drop_inode     = ext4_drop_inode,
1653         .evict_inode    = ext4_evict_inode,
1654         .put_super      = ext4_put_super,
1655         .sync_fs        = ext4_sync_fs,
1656         .freeze_fs      = ext4_freeze,
1657         .unfreeze_fs    = ext4_unfreeze,
1658         .statfs         = ext4_statfs,
1659         .remount_fs     = ext4_remount,
1660         .show_options   = ext4_show_options,
1661 #ifdef CONFIG_QUOTA
1662         .quota_read     = ext4_quota_read,
1663         .quota_write    = ext4_quota_write,
1664         .get_dquots     = ext4_get_dquots,
1665 #endif
1666         .bdev_try_to_free_page = bdev_try_to_free_page,
1667 };
1668
1669 static const struct export_operations ext4_export_ops = {
1670         .fh_to_dentry = ext4_fh_to_dentry,
1671         .fh_to_parent = ext4_fh_to_parent,
1672         .get_parent = ext4_get_parent,
1673         .commit_metadata = ext4_nfs_commit_metadata,
1674 };
1675
1676 enum {
1677         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1678         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1679         Opt_nouid32, Opt_debug, Opt_removed,
1680         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1681         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1682         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1683         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1684         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1685         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1686         Opt_inlinecrypt,
1687         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1688         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1689         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1690         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
1691         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1692         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1693         Opt_nowarn_on_error, Opt_mblk_io_submit,
1694         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1695         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1696         Opt_inode_readahead_blks, Opt_journal_ioprio,
1697         Opt_dioread_nolock, Opt_dioread_lock,
1698         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1699         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1700         Opt_no_prefetch_block_bitmaps, Opt_mb_optimize_scan,
1701 #ifdef CONFIG_EXT4_DEBUG
1702         Opt_fc_debug_max_replay, Opt_fc_debug_force
1703 #endif
1704 };
1705
1706 static const match_table_t tokens = {
1707         {Opt_bsd_df, "bsddf"},
1708         {Opt_minix_df, "minixdf"},
1709         {Opt_grpid, "grpid"},
1710         {Opt_grpid, "bsdgroups"},
1711         {Opt_nogrpid, "nogrpid"},
1712         {Opt_nogrpid, "sysvgroups"},
1713         {Opt_resgid, "resgid=%u"},
1714         {Opt_resuid, "resuid=%u"},
1715         {Opt_sb, "sb=%u"},
1716         {Opt_err_cont, "errors=continue"},
1717         {Opt_err_panic, "errors=panic"},
1718         {Opt_err_ro, "errors=remount-ro"},
1719         {Opt_nouid32, "nouid32"},
1720         {Opt_debug, "debug"},
1721         {Opt_removed, "oldalloc"},
1722         {Opt_removed, "orlov"},
1723         {Opt_user_xattr, "user_xattr"},
1724         {Opt_nouser_xattr, "nouser_xattr"},
1725         {Opt_acl, "acl"},
1726         {Opt_noacl, "noacl"},
1727         {Opt_noload, "norecovery"},
1728         {Opt_noload, "noload"},
1729         {Opt_removed, "nobh"},
1730         {Opt_removed, "bh"},
1731         {Opt_commit, "commit=%u"},
1732         {Opt_min_batch_time, "min_batch_time=%u"},
1733         {Opt_max_batch_time, "max_batch_time=%u"},
1734         {Opt_journal_dev, "journal_dev=%u"},
1735         {Opt_journal_path, "journal_path=%s"},
1736         {Opt_journal_checksum, "journal_checksum"},
1737         {Opt_nojournal_checksum, "nojournal_checksum"},
1738         {Opt_journal_async_commit, "journal_async_commit"},
1739         {Opt_abort, "abort"},
1740         {Opt_data_journal, "data=journal"},
1741         {Opt_data_ordered, "data=ordered"},
1742         {Opt_data_writeback, "data=writeback"},
1743         {Opt_data_err_abort, "data_err=abort"},
1744         {Opt_data_err_ignore, "data_err=ignore"},
1745         {Opt_offusrjquota, "usrjquota="},
1746         {Opt_usrjquota, "usrjquota=%s"},
1747         {Opt_offgrpjquota, "grpjquota="},
1748         {Opt_grpjquota, "grpjquota=%s"},
1749         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1750         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1751         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1752         {Opt_grpquota, "grpquota"},
1753         {Opt_noquota, "noquota"},
1754         {Opt_quota, "quota"},
1755         {Opt_usrquota, "usrquota"},
1756         {Opt_prjquota, "prjquota"},
1757         {Opt_barrier, "barrier=%u"},
1758         {Opt_barrier, "barrier"},
1759         {Opt_nobarrier, "nobarrier"},
1760         {Opt_i_version, "i_version"},
1761         {Opt_dax, "dax"},
1762         {Opt_dax_always, "dax=always"},
1763         {Opt_dax_inode, "dax=inode"},
1764         {Opt_dax_never, "dax=never"},
1765         {Opt_stripe, "stripe=%u"},
1766         {Opt_delalloc, "delalloc"},
1767         {Opt_warn_on_error, "warn_on_error"},
1768         {Opt_nowarn_on_error, "nowarn_on_error"},
1769         {Opt_lazytime, "lazytime"},
1770         {Opt_nolazytime, "nolazytime"},
1771         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1772         {Opt_nodelalloc, "nodelalloc"},
1773         {Opt_removed, "mblk_io_submit"},
1774         {Opt_removed, "nomblk_io_submit"},
1775         {Opt_block_validity, "block_validity"},
1776         {Opt_noblock_validity, "noblock_validity"},
1777         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1778         {Opt_journal_ioprio, "journal_ioprio=%u"},
1779         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1780         {Opt_auto_da_alloc, "auto_da_alloc"},
1781         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1782         {Opt_dioread_nolock, "dioread_nolock"},
1783         {Opt_dioread_lock, "nodioread_nolock"},
1784         {Opt_dioread_lock, "dioread_lock"},
1785         {Opt_discard, "discard"},
1786         {Opt_nodiscard, "nodiscard"},
1787         {Opt_init_itable, "init_itable=%u"},
1788         {Opt_init_itable, "init_itable"},
1789         {Opt_noinit_itable, "noinit_itable"},
1790 #ifdef CONFIG_EXT4_DEBUG
1791         {Opt_fc_debug_force, "fc_debug_force"},
1792         {Opt_fc_debug_max_replay, "fc_debug_max_replay=%u"},
1793 #endif
1794         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1795         {Opt_test_dummy_encryption, "test_dummy_encryption=%s"},
1796         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1797         {Opt_inlinecrypt, "inlinecrypt"},
1798         {Opt_nombcache, "nombcache"},
1799         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1800         {Opt_removed, "prefetch_block_bitmaps"},
1801         {Opt_no_prefetch_block_bitmaps, "no_prefetch_block_bitmaps"},
1802         {Opt_mb_optimize_scan, "mb_optimize_scan=%d"},
1803         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1804         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1805         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1806         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1807         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1808         {Opt_err, NULL},
1809 };
1810
1811 static ext4_fsblk_t get_sb_block(void **data)
1812 {
1813         ext4_fsblk_t    sb_block;
1814         char            *options = (char *) *data;
1815
1816         if (!options || strncmp(options, "sb=", 3) != 0)
1817                 return 1;       /* Default location */
1818
1819         options += 3;
1820         /* TODO: use simple_strtoll with >32bit ext4 */
1821         sb_block = simple_strtoul(options, &options, 0);
1822         if (*options && *options != ',') {
1823                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1824                        (char *) *data);
1825                 return 1;
1826         }
1827         if (*options == ',')
1828                 options++;
1829         *data = (void *) options;
1830
1831         return sb_block;
1832 }
1833
1834 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1835 #define DEFAULT_MB_OPTIMIZE_SCAN        (-1)
1836
1837 static const char deprecated_msg[] =
1838         "Mount option \"%s\" will be removed by %s\n"
1839         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1840
1841 #ifdef CONFIG_QUOTA
1842 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1843 {
1844         struct ext4_sb_info *sbi = EXT4_SB(sb);
1845         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1846         int ret = -1;
1847
1848         if (sb_any_quota_loaded(sb) && !old_qname) {
1849                 ext4_msg(sb, KERN_ERR,
1850                         "Cannot change journaled "
1851                         "quota options when quota turned on");
1852                 return -1;
1853         }
1854         if (ext4_has_feature_quota(sb)) {
1855                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1856                          "ignored when QUOTA feature is enabled");
1857                 return 1;
1858         }
1859         qname = match_strdup(args);
1860         if (!qname) {
1861                 ext4_msg(sb, KERN_ERR,
1862                         "Not enough memory for storing quotafile name");
1863                 return -1;
1864         }
1865         if (old_qname) {
1866                 if (strcmp(old_qname, qname) == 0)
1867                         ret = 1;
1868                 else
1869                         ext4_msg(sb, KERN_ERR,
1870                                  "%s quota file already specified",
1871                                  QTYPE2NAME(qtype));
1872                 goto errout;
1873         }
1874         if (strchr(qname, '/')) {
1875                 ext4_msg(sb, KERN_ERR,
1876                         "quotafile must be on filesystem root");
1877                 goto errout;
1878         }
1879         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1880         set_opt(sb, QUOTA);
1881         return 1;
1882 errout:
1883         kfree(qname);
1884         return ret;
1885 }
1886
1887 static int clear_qf_name(struct super_block *sb, int qtype)
1888 {
1889
1890         struct ext4_sb_info *sbi = EXT4_SB(sb);
1891         char *old_qname = get_qf_name(sb, sbi, qtype);
1892
1893         if (sb_any_quota_loaded(sb) && old_qname) {
1894                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1895                         " when quota turned on");
1896                 return -1;
1897         }
1898         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1899         synchronize_rcu();
1900         kfree(old_qname);
1901         return 1;
1902 }
1903 #endif
1904
1905 #define MOPT_SET        0x0001
1906 #define MOPT_CLEAR      0x0002
1907 #define MOPT_NOSUPPORT  0x0004
1908 #define MOPT_EXPLICIT   0x0008
1909 #define MOPT_CLEAR_ERR  0x0010
1910 #define MOPT_GTE0       0x0020
1911 #ifdef CONFIG_QUOTA
1912 #define MOPT_Q          0
1913 #define MOPT_QFMT       0x0040
1914 #else
1915 #define MOPT_Q          MOPT_NOSUPPORT
1916 #define MOPT_QFMT       MOPT_NOSUPPORT
1917 #endif
1918 #define MOPT_DATAJ      0x0080
1919 #define MOPT_NO_EXT2    0x0100
1920 #define MOPT_NO_EXT3    0x0200
1921 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1922 #define MOPT_STRING     0x0400
1923 #define MOPT_SKIP       0x0800
1924 #define MOPT_2          0x1000
1925
1926 static const struct mount_opts {
1927         int     token;
1928         int     mount_opt;
1929         int     flags;
1930 } ext4_mount_opts[] = {
1931         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1932         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1933         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1934         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1935         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1936         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1937         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1938          MOPT_EXT4_ONLY | MOPT_SET},
1939         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1940          MOPT_EXT4_ONLY | MOPT_CLEAR},
1941         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1942         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1943         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1944          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1945         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1946          MOPT_EXT4_ONLY | MOPT_CLEAR},
1947         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1948         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1949         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1950          MOPT_EXT4_ONLY | MOPT_CLEAR},
1951         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1952          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1953         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1954                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1955          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1956         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1957         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1958         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1959         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1960         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1961          MOPT_NO_EXT2},
1962         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1963          MOPT_NO_EXT2},
1964         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1965         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1966         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1967         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1968         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1969         {Opt_commit, 0, MOPT_GTE0},
1970         {Opt_max_batch_time, 0, MOPT_GTE0},
1971         {Opt_min_batch_time, 0, MOPT_GTE0},
1972         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1973         {Opt_init_itable, 0, MOPT_GTE0},
1974         {Opt_dax, EXT4_MOUNT_DAX_ALWAYS, MOPT_SET | MOPT_SKIP},
1975         {Opt_dax_always, EXT4_MOUNT_DAX_ALWAYS,
1976                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1977         {Opt_dax_inode, EXT4_MOUNT2_DAX_INODE,
1978                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1979         {Opt_dax_never, EXT4_MOUNT2_DAX_NEVER,
1980                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1981         {Opt_stripe, 0, MOPT_GTE0},
1982         {Opt_resuid, 0, MOPT_GTE0},
1983         {Opt_resgid, 0, MOPT_GTE0},
1984         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1985         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1986         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1987         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1988         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1989         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1990          MOPT_NO_EXT2 | MOPT_DATAJ},
1991         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1992         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1993 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1994         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1995         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1996 #else
1997         {Opt_acl, 0, MOPT_NOSUPPORT},
1998         {Opt_noacl, 0, MOPT_NOSUPPORT},
1999 #endif
2000         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
2001         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
2002         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
2003         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
2004         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
2005                                                         MOPT_SET | MOPT_Q},
2006         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
2007                                                         MOPT_SET | MOPT_Q},
2008         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
2009                                                         MOPT_SET | MOPT_Q},
2010         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2011                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
2012                                                         MOPT_CLEAR | MOPT_Q},
2013         {Opt_usrjquota, 0, MOPT_Q | MOPT_STRING},
2014         {Opt_grpjquota, 0, MOPT_Q | MOPT_STRING},
2015         {Opt_offusrjquota, 0, MOPT_Q},
2016         {Opt_offgrpjquota, 0, MOPT_Q},
2017         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
2018         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
2019         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
2020         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
2021         {Opt_test_dummy_encryption, 0, MOPT_STRING},
2022         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
2023         {Opt_no_prefetch_block_bitmaps, EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS,
2024          MOPT_SET},
2025         {Opt_mb_optimize_scan, EXT4_MOUNT2_MB_OPTIMIZE_SCAN, MOPT_GTE0},
2026 #ifdef CONFIG_EXT4_DEBUG
2027         {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
2028          MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
2029         {Opt_fc_debug_max_replay, 0, MOPT_GTE0},
2030 #endif
2031         {Opt_err, 0, 0}
2032 };
2033
2034 #ifdef CONFIG_UNICODE
2035 static const struct ext4_sb_encodings {
2036         __u16 magic;
2037         char *name;
2038         char *version;
2039 } ext4_sb_encoding_map[] = {
2040         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
2041 };
2042
2043 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
2044                                  const struct ext4_sb_encodings **encoding,
2045                                  __u16 *flags)
2046 {
2047         __u16 magic = le16_to_cpu(es->s_encoding);
2048         int i;
2049
2050         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
2051                 if (magic == ext4_sb_encoding_map[i].magic)
2052                         break;
2053
2054         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
2055                 return -EINVAL;
2056
2057         *encoding = &ext4_sb_encoding_map[i];
2058         *flags = le16_to_cpu(es->s_encoding_flags);
2059
2060         return 0;
2061 }
2062 #endif
2063
2064 static int ext4_set_test_dummy_encryption(struct super_block *sb,
2065                                           const char *opt,
2066                                           const substring_t *arg,
2067                                           bool is_remount)
2068 {
2069 #ifdef CONFIG_FS_ENCRYPTION
2070         struct ext4_sb_info *sbi = EXT4_SB(sb);
2071         int err;
2072
2073         /*
2074          * This mount option is just for testing, and it's not worthwhile to
2075          * implement the extra complexity (e.g. RCU protection) that would be
2076          * needed to allow it to be set or changed during remount.  We do allow
2077          * it to be specified during remount, but only if there is no change.
2078          */
2079         if (is_remount && !sbi->s_dummy_enc_policy.policy) {
2080                 ext4_msg(sb, KERN_WARNING,
2081                          "Can't set test_dummy_encryption on remount");
2082                 return -1;
2083         }
2084         err = fscrypt_set_test_dummy_encryption(sb, arg->from,
2085                                                 &sbi->s_dummy_enc_policy);
2086         if (err) {
2087                 if (err == -EEXIST)
2088                         ext4_msg(sb, KERN_WARNING,
2089                                  "Can't change test_dummy_encryption on remount");
2090                 else if (err == -EINVAL)
2091                         ext4_msg(sb, KERN_WARNING,
2092                                  "Value of option \"%s\" is unrecognized", opt);
2093                 else
2094                         ext4_msg(sb, KERN_WARNING,
2095                                  "Error processing option \"%s\" [%d]",
2096                                  opt, err);
2097                 return -1;
2098         }
2099         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2100 #else
2101         ext4_msg(sb, KERN_WARNING,
2102                  "Test dummy encryption mount option ignored");
2103 #endif
2104         return 1;
2105 }
2106
2107 struct ext4_parsed_options {
2108         unsigned long journal_devnum;
2109         unsigned int journal_ioprio;
2110         int mb_optimize_scan;
2111 };
2112
2113 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
2114                             substring_t *args, struct ext4_parsed_options *parsed_opts,
2115                             int is_remount)
2116 {
2117         struct ext4_sb_info *sbi = EXT4_SB(sb);
2118         const struct mount_opts *m;
2119         kuid_t uid;
2120         kgid_t gid;
2121         int arg = 0;
2122
2123 #ifdef CONFIG_QUOTA
2124         if (token == Opt_usrjquota)
2125                 return set_qf_name(sb, USRQUOTA, &args[0]);
2126         else if (token == Opt_grpjquota)
2127                 return set_qf_name(sb, GRPQUOTA, &args[0]);
2128         else if (token == Opt_offusrjquota)
2129                 return clear_qf_name(sb, USRQUOTA);
2130         else if (token == Opt_offgrpjquota)
2131                 return clear_qf_name(sb, GRPQUOTA);
2132 #endif
2133         switch (token) {
2134         case Opt_noacl:
2135         case Opt_nouser_xattr:
2136                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
2137                 break;
2138         case Opt_sb:
2139                 return 1;       /* handled by get_sb_block() */
2140         case Opt_removed:
2141                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
2142                 return 1;
2143         case Opt_abort:
2144                 ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
2145                 return 1;
2146         case Opt_i_version:
2147                 sb->s_flags |= SB_I_VERSION;
2148                 return 1;
2149         case Opt_lazytime:
2150                 sb->s_flags |= SB_LAZYTIME;
2151                 return 1;
2152         case Opt_nolazytime:
2153                 sb->s_flags &= ~SB_LAZYTIME;
2154                 return 1;
2155         case Opt_inlinecrypt:
2156 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2157                 sb->s_flags |= SB_INLINECRYPT;
2158 #else
2159                 ext4_msg(sb, KERN_ERR, "inline encryption not supported");
2160 #endif
2161                 return 1;
2162         }
2163
2164         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2165                 if (token == m->token)
2166                         break;
2167
2168         if (m->token == Opt_err) {
2169                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
2170                          "or missing value", opt);
2171                 return -1;
2172         }
2173
2174         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2175                 ext4_msg(sb, KERN_ERR,
2176                          "Mount option \"%s\" incompatible with ext2", opt);
2177                 return -1;
2178         }
2179         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2180                 ext4_msg(sb, KERN_ERR,
2181                          "Mount option \"%s\" incompatible with ext3", opt);
2182                 return -1;
2183         }
2184
2185         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
2186                 return -1;
2187         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
2188                 return -1;
2189         if (m->flags & MOPT_EXPLICIT) {
2190                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2191                         set_opt2(sb, EXPLICIT_DELALLOC);
2192                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2193                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
2194                 } else
2195                         return -1;
2196         }
2197         if (m->flags & MOPT_CLEAR_ERR)
2198                 clear_opt(sb, ERRORS_MASK);
2199         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
2200                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
2201                          "options when quota turned on");
2202                 return -1;
2203         }
2204
2205         if (m->flags & MOPT_NOSUPPORT) {
2206                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
2207         } else if (token == Opt_commit) {
2208                 if (arg == 0)
2209                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
2210                 else if (arg > INT_MAX / HZ) {
2211                         ext4_msg(sb, KERN_ERR,
2212                                  "Invalid commit interval %d, "
2213                                  "must be smaller than %d",
2214                                  arg, INT_MAX / HZ);
2215                         return -1;
2216                 }
2217                 sbi->s_commit_interval = HZ * arg;
2218         } else if (token == Opt_debug_want_extra_isize) {
2219                 if ((arg & 1) ||
2220                     (arg < 4) ||
2221                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
2222                         ext4_msg(sb, KERN_ERR,
2223                                  "Invalid want_extra_isize %d", arg);
2224                         return -1;
2225                 }
2226                 sbi->s_want_extra_isize = arg;
2227         } else if (token == Opt_max_batch_time) {
2228                 sbi->s_max_batch_time = arg;
2229         } else if (token == Opt_min_batch_time) {
2230                 sbi->s_min_batch_time = arg;
2231         } else if (token == Opt_inode_readahead_blks) {
2232                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
2233                         ext4_msg(sb, KERN_ERR,
2234                                  "EXT4-fs: inode_readahead_blks must be "
2235                                  "0 or a power of 2 smaller than 2^31");
2236                         return -1;
2237                 }
2238                 sbi->s_inode_readahead_blks = arg;
2239         } else if (token == Opt_init_itable) {
2240                 set_opt(sb, INIT_INODE_TABLE);
2241                 if (!args->from)
2242                         arg = EXT4_DEF_LI_WAIT_MULT;
2243                 sbi->s_li_wait_mult = arg;
2244         } else if (token == Opt_max_dir_size_kb) {
2245                 sbi->s_max_dir_size_kb = arg;
2246 #ifdef CONFIG_EXT4_DEBUG
2247         } else if (token == Opt_fc_debug_max_replay) {
2248                 sbi->s_fc_debug_max_replay = arg;
2249 #endif
2250         } else if (token == Opt_stripe) {
2251                 sbi->s_stripe = arg;
2252         } else if (token == Opt_resuid) {
2253                 uid = make_kuid(current_user_ns(), arg);
2254                 if (!uid_valid(uid)) {
2255                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
2256                         return -1;
2257                 }
2258                 sbi->s_resuid = uid;
2259         } else if (token == Opt_resgid) {
2260                 gid = make_kgid(current_user_ns(), arg);
2261                 if (!gid_valid(gid)) {
2262                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
2263                         return -1;
2264                 }
2265                 sbi->s_resgid = gid;
2266         } else if (token == Opt_journal_dev) {
2267                 if (is_remount) {
2268                         ext4_msg(sb, KERN_ERR,
2269                                  "Cannot specify journal on remount");
2270                         return -1;
2271                 }
2272                 parsed_opts->journal_devnum = arg;
2273         } else if (token == Opt_journal_path) {
2274                 char *journal_path;
2275                 struct inode *journal_inode;
2276                 struct path path;
2277                 int error;
2278
2279                 if (is_remount) {
2280                         ext4_msg(sb, KERN_ERR,
2281                                  "Cannot specify journal on remount");
2282                         return -1;
2283                 }
2284                 journal_path = match_strdup(&args[0]);
2285                 if (!journal_path) {
2286                         ext4_msg(sb, KERN_ERR, "error: could not dup "
2287                                 "journal device string");
2288                         return -1;
2289                 }
2290
2291                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2292                 if (error) {
2293                         ext4_msg(sb, KERN_ERR, "error: could not find "
2294                                 "journal device path: error %d", error);
2295                         kfree(journal_path);
2296                         return -1;
2297                 }
2298
2299                 journal_inode = d_inode(path.dentry);
2300                 if (!S_ISBLK(journal_inode->i_mode)) {
2301                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
2302                                 "is not a block device", journal_path);
2303                         path_put(&path);
2304                         kfree(journal_path);
2305                         return -1;
2306                 }
2307
2308                 parsed_opts->journal_devnum = new_encode_dev(journal_inode->i_rdev);
2309                 path_put(&path);
2310                 kfree(journal_path);
2311         } else if (token == Opt_journal_ioprio) {
2312                 if (arg > 7) {
2313                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2314                                  " (must be 0-7)");
2315                         return -1;
2316                 }
2317                 parsed_opts->journal_ioprio =
2318                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2319         } else if (token == Opt_test_dummy_encryption) {
2320                 return ext4_set_test_dummy_encryption(sb, opt, &args[0],
2321                                                       is_remount);
2322         } else if (m->flags & MOPT_DATAJ) {
2323                 if (is_remount) {
2324                         if (!sbi->s_journal)
2325                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2326                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2327                                 ext4_msg(sb, KERN_ERR,
2328                                          "Cannot change data mode on remount");
2329                                 return -1;
2330                         }
2331                 } else {
2332                         clear_opt(sb, DATA_FLAGS);
2333                         sbi->s_mount_opt |= m->mount_opt;
2334                 }
2335 #ifdef CONFIG_QUOTA
2336         } else if (m->flags & MOPT_QFMT) {
2337                 if (sb_any_quota_loaded(sb) &&
2338                     sbi->s_jquota_fmt != m->mount_opt) {
2339                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2340                                  "quota options when quota turned on");
2341                         return -1;
2342                 }
2343                 if (ext4_has_feature_quota(sb)) {
2344                         ext4_msg(sb, KERN_INFO,
2345                                  "Quota format mount options ignored "
2346                                  "when QUOTA feature is enabled");
2347                         return 1;
2348                 }
2349                 sbi->s_jquota_fmt = m->mount_opt;
2350 #endif
2351         } else if (token == Opt_dax || token == Opt_dax_always ||
2352                    token == Opt_dax_inode || token == Opt_dax_never) {
2353 #ifdef CONFIG_FS_DAX
2354                 switch (token) {
2355                 case Opt_dax:
2356                 case Opt_dax_always:
2357                         if (is_remount &&
2358                             (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2359                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2360                         fail_dax_change_remount:
2361                                 ext4_msg(sb, KERN_ERR, "can't change "
2362                                          "dax mount option while remounting");
2363                                 return -1;
2364                         }
2365                         if (is_remount &&
2366                             (test_opt(sb, DATA_FLAGS) ==
2367                              EXT4_MOUNT_JOURNAL_DATA)) {
2368                                     ext4_msg(sb, KERN_ERR, "can't mount with "
2369                                              "both data=journal and dax");
2370                                     return -1;
2371                         }
2372                         ext4_msg(sb, KERN_WARNING,
2373                                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2374                         sbi->s_mount_opt |= EXT4_MOUNT_DAX_ALWAYS;
2375                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2376                         break;
2377                 case Opt_dax_never:
2378                         if (is_remount &&
2379                             (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2380                              (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS)))
2381                                 goto fail_dax_change_remount;
2382                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2383                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2384                         break;
2385                 case Opt_dax_inode:
2386                         if (is_remount &&
2387                             ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2388                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2389                              !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE)))
2390                                 goto fail_dax_change_remount;
2391                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2392                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2393                         /* Strictly for printing options */
2394                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_INODE;
2395                         break;
2396                 }
2397 #else
2398                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2399                 sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2400                 sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2401                 return -1;
2402 #endif
2403         } else if (token == Opt_data_err_abort) {
2404                 sbi->s_mount_opt |= m->mount_opt;
2405         } else if (token == Opt_data_err_ignore) {
2406                 sbi->s_mount_opt &= ~m->mount_opt;
2407         } else if (token == Opt_mb_optimize_scan) {
2408                 if (arg != 0 && arg != 1) {
2409                         ext4_msg(sb, KERN_WARNING,
2410                                  "mb_optimize_scan should be set to 0 or 1.");
2411                         return -1;
2412                 }
2413                 parsed_opts->mb_optimize_scan = arg;
2414         } else {
2415                 if (!args->from)
2416                         arg = 1;
2417                 if (m->flags & MOPT_CLEAR)
2418                         arg = !arg;
2419                 else if (unlikely(!(m->flags & MOPT_SET))) {
2420                         ext4_msg(sb, KERN_WARNING,
2421                                  "buggy handling of option %s", opt);
2422                         WARN_ON(1);
2423                         return -1;
2424                 }
2425                 if (m->flags & MOPT_2) {
2426                         if (arg != 0)
2427                                 sbi->s_mount_opt2 |= m->mount_opt;
2428                         else
2429                                 sbi->s_mount_opt2 &= ~m->mount_opt;
2430                 } else {
2431                         if (arg != 0)
2432                                 sbi->s_mount_opt |= m->mount_opt;
2433                         else
2434                                 sbi->s_mount_opt &= ~m->mount_opt;
2435                 }
2436         }
2437         return 1;
2438 }
2439
2440 static int parse_options(char *options, struct super_block *sb,
2441                          struct ext4_parsed_options *ret_opts,
2442                          int is_remount)
2443 {
2444         struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2445         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2446         substring_t args[MAX_OPT_ARGS];
2447         int token;
2448
2449         if (!options)
2450                 return 1;
2451
2452         while ((p = strsep(&options, ",")) != NULL) {
2453                 if (!*p)
2454                         continue;
2455                 /*
2456                  * Initialize args struct so we know whether arg was
2457                  * found; some options take optional arguments.
2458                  */
2459                 args[0].to = args[0].from = NULL;
2460                 token = match_token(p, tokens, args);
2461                 if (handle_mount_opt(sb, p, token, args, ret_opts,
2462                                      is_remount) < 0)
2463                         return 0;
2464         }
2465 #ifdef CONFIG_QUOTA
2466         /*
2467          * We do the test below only for project quotas. 'usrquota' and
2468          * 'grpquota' mount options are allowed even without quota feature
2469          * to support legacy quotas in quota files.
2470          */
2471         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2472                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2473                          "Cannot enable project quota enforcement.");
2474                 return 0;
2475         }
2476         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2477         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2478         if (usr_qf_name || grp_qf_name) {
2479                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2480                         clear_opt(sb, USRQUOTA);
2481
2482                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2483                         clear_opt(sb, GRPQUOTA);
2484
2485                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2486                         ext4_msg(sb, KERN_ERR, "old and new quota "
2487                                         "format mixing");
2488                         return 0;
2489                 }
2490
2491                 if (!sbi->s_jquota_fmt) {
2492                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2493                                         "not specified");
2494                         return 0;
2495                 }
2496         }
2497 #endif
2498         if (test_opt(sb, DIOREAD_NOLOCK)) {
2499                 int blocksize =
2500                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2501                 if (blocksize < PAGE_SIZE)
2502                         ext4_msg(sb, KERN_WARNING, "Warning: mounting with an "
2503                                  "experimental mount option 'dioread_nolock' "
2504                                  "for blocksize < PAGE_SIZE");
2505         }
2506         return 1;
2507 }
2508
2509 static inline void ext4_show_quota_options(struct seq_file *seq,
2510                                            struct super_block *sb)
2511 {
2512 #if defined(CONFIG_QUOTA)
2513         struct ext4_sb_info *sbi = EXT4_SB(sb);
2514         char *usr_qf_name, *grp_qf_name;
2515
2516         if (sbi->s_jquota_fmt) {
2517                 char *fmtname = "";
2518
2519                 switch (sbi->s_jquota_fmt) {
2520                 case QFMT_VFS_OLD:
2521                         fmtname = "vfsold";
2522                         break;
2523                 case QFMT_VFS_V0:
2524                         fmtname = "vfsv0";
2525                         break;
2526                 case QFMT_VFS_V1:
2527                         fmtname = "vfsv1";
2528                         break;
2529                 }
2530                 seq_printf(seq, ",jqfmt=%s", fmtname);
2531         }
2532
2533         rcu_read_lock();
2534         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2535         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2536         if (usr_qf_name)
2537                 seq_show_option(seq, "usrjquota", usr_qf_name);
2538         if (grp_qf_name)
2539                 seq_show_option(seq, "grpjquota", grp_qf_name);
2540         rcu_read_unlock();
2541 #endif
2542 }
2543
2544 static const char *token2str(int token)
2545 {
2546         const struct match_token *t;
2547
2548         for (t = tokens; t->token != Opt_err; t++)
2549                 if (t->token == token && !strchr(t->pattern, '='))
2550                         break;
2551         return t->pattern;
2552 }
2553
2554 /*
2555  * Show an option if
2556  *  - it's set to a non-default value OR
2557  *  - if the per-sb default is different from the global default
2558  */
2559 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2560                               int nodefs)
2561 {
2562         struct ext4_sb_info *sbi = EXT4_SB(sb);
2563         struct ext4_super_block *es = sbi->s_es;
2564         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2565         const struct mount_opts *m;
2566         char sep = nodefs ? '\n' : ',';
2567
2568 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2569 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2570
2571         if (sbi->s_sb_block != 1)
2572                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2573
2574         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2575                 int want_set = m->flags & MOPT_SET;
2576                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2577                     (m->flags & MOPT_CLEAR_ERR) || m->flags & MOPT_SKIP)
2578                         continue;
2579                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2580                         continue; /* skip if same as the default */
2581                 if ((want_set &&
2582                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2583                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2584                         continue; /* select Opt_noFoo vs Opt_Foo */
2585                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2586         }
2587
2588         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2589             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2590                 SEQ_OPTS_PRINT("resuid=%u",
2591                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2592         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2593             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2594                 SEQ_OPTS_PRINT("resgid=%u",
2595                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2596         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2597         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2598                 SEQ_OPTS_PUTS("errors=remount-ro");
2599         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2600                 SEQ_OPTS_PUTS("errors=continue");
2601         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2602                 SEQ_OPTS_PUTS("errors=panic");
2603         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2604                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2605         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2606                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2607         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2608                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2609         if (sb->s_flags & SB_I_VERSION)
2610                 SEQ_OPTS_PUTS("i_version");
2611         if (nodefs || sbi->s_stripe)
2612                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2613         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2614                         (sbi->s_mount_opt ^ def_mount_opt)) {
2615                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2616                         SEQ_OPTS_PUTS("data=journal");
2617                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2618                         SEQ_OPTS_PUTS("data=ordered");
2619                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2620                         SEQ_OPTS_PUTS("data=writeback");
2621         }
2622         if (nodefs ||
2623             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2624                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2625                                sbi->s_inode_readahead_blks);
2626
2627         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2628                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2629                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2630         if (nodefs || sbi->s_max_dir_size_kb)
2631                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2632         if (test_opt(sb, DATA_ERR_ABORT))
2633                 SEQ_OPTS_PUTS("data_err=abort");
2634
2635         fscrypt_show_test_dummy_encryption(seq, sep, sb);
2636
2637         if (sb->s_flags & SB_INLINECRYPT)
2638                 SEQ_OPTS_PUTS("inlinecrypt");
2639
2640         if (test_opt(sb, DAX_ALWAYS)) {
2641                 if (IS_EXT2_SB(sb))
2642                         SEQ_OPTS_PUTS("dax");
2643                 else
2644                         SEQ_OPTS_PUTS("dax=always");
2645         } else if (test_opt2(sb, DAX_NEVER)) {
2646                 SEQ_OPTS_PUTS("dax=never");
2647         } else if (test_opt2(sb, DAX_INODE)) {
2648                 SEQ_OPTS_PUTS("dax=inode");
2649         }
2650         ext4_show_quota_options(seq, sb);
2651         return 0;
2652 }
2653
2654 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2655 {
2656         return _ext4_show_options(seq, root->d_sb, 0);
2657 }
2658
2659 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2660 {
2661         struct super_block *sb = seq->private;
2662         int rc;
2663
2664         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2665         rc = _ext4_show_options(seq, sb, 1);
2666         seq_puts(seq, "\n");
2667         return rc;
2668 }
2669
2670 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2671                             int read_only)
2672 {
2673         struct ext4_sb_info *sbi = EXT4_SB(sb);
2674         int err = 0;
2675
2676         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2677                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2678                          "forcing read-only mode");
2679                 err = -EROFS;
2680                 goto done;
2681         }
2682         if (read_only)
2683                 goto done;
2684         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2685                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2686                          "running e2fsck is recommended");
2687         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2688                 ext4_msg(sb, KERN_WARNING,
2689                          "warning: mounting fs with errors, "
2690                          "running e2fsck is recommended");
2691         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2692                  le16_to_cpu(es->s_mnt_count) >=
2693                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2694                 ext4_msg(sb, KERN_WARNING,
2695                          "warning: maximal mount count reached, "
2696                          "running e2fsck is recommended");
2697         else if (le32_to_cpu(es->s_checkinterval) &&
2698                  (ext4_get_tstamp(es, s_lastcheck) +
2699                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2700                 ext4_msg(sb, KERN_WARNING,
2701                          "warning: checktime reached, "
2702                          "running e2fsck is recommended");
2703         if (!sbi->s_journal)
2704                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2705         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2706                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2707         le16_add_cpu(&es->s_mnt_count, 1);
2708         ext4_update_tstamp(es, s_mtime);
2709         if (sbi->s_journal)
2710                 ext4_set_feature_journal_needs_recovery(sb);
2711
2712         err = ext4_commit_super(sb);
2713 done:
2714         if (test_opt(sb, DEBUG))
2715                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2716                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2717                         sb->s_blocksize,
2718                         sbi->s_groups_count,
2719                         EXT4_BLOCKS_PER_GROUP(sb),
2720                         EXT4_INODES_PER_GROUP(sb),
2721                         sbi->s_mount_opt, sbi->s_mount_opt2);
2722
2723         cleancache_init_fs(sb);
2724         return err;
2725 }
2726
2727 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2728 {
2729         struct ext4_sb_info *sbi = EXT4_SB(sb);
2730         struct flex_groups **old_groups, **new_groups;
2731         int size, i, j;
2732
2733         if (!sbi->s_log_groups_per_flex)
2734                 return 0;
2735
2736         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2737         if (size <= sbi->s_flex_groups_allocated)
2738                 return 0;
2739
2740         new_groups = kvzalloc(roundup_pow_of_two(size *
2741                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2742         if (!new_groups) {
2743                 ext4_msg(sb, KERN_ERR,
2744                          "not enough memory for %d flex group pointers", size);
2745                 return -ENOMEM;
2746         }
2747         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2748                 new_groups[i] = kvzalloc(roundup_pow_of_two(
2749                                          sizeof(struct flex_groups)),
2750                                          GFP_KERNEL);
2751                 if (!new_groups[i]) {
2752                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
2753                                 kvfree(new_groups[j]);
2754                         kvfree(new_groups);
2755                         ext4_msg(sb, KERN_ERR,
2756                                  "not enough memory for %d flex groups", size);
2757                         return -ENOMEM;
2758                 }
2759         }
2760         rcu_read_lock();
2761         old_groups = rcu_dereference(sbi->s_flex_groups);
2762         if (old_groups)
2763                 memcpy(new_groups, old_groups,
2764                        (sbi->s_flex_groups_allocated *
2765                         sizeof(struct flex_groups *)));
2766         rcu_read_unlock();
2767         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2768         sbi->s_flex_groups_allocated = size;
2769         if (old_groups)
2770                 ext4_kvfree_array_rcu(old_groups);
2771         return 0;
2772 }
2773
2774 static int ext4_fill_flex_info(struct super_block *sb)
2775 {
2776         struct ext4_sb_info *sbi = EXT4_SB(sb);
2777         struct ext4_group_desc *gdp = NULL;
2778         struct flex_groups *fg;
2779         ext4_group_t flex_group;
2780         int i, err;
2781
2782         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2783         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2784                 sbi->s_log_groups_per_flex = 0;
2785                 return 1;
2786         }
2787
2788         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2789         if (err)
2790                 goto failed;
2791
2792         for (i = 0; i < sbi->s_groups_count; i++) {
2793                 gdp = ext4_get_group_desc(sb, i, NULL);
2794
2795                 flex_group = ext4_flex_group(sbi, i);
2796                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2797                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2798                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2799                              &fg->free_clusters);
2800                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2801         }
2802
2803         return 1;
2804 failed:
2805         return 0;
2806 }
2807
2808 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2809                                    struct ext4_group_desc *gdp)
2810 {
2811         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2812         __u16 crc = 0;
2813         __le32 le_group = cpu_to_le32(block_group);
2814         struct ext4_sb_info *sbi = EXT4_SB(sb);
2815
2816         if (ext4_has_metadata_csum(sbi->s_sb)) {
2817                 /* Use new metadata_csum algorithm */
2818                 __u32 csum32;
2819                 __u16 dummy_csum = 0;
2820
2821                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2822                                      sizeof(le_group));
2823                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2824                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2825                                      sizeof(dummy_csum));
2826                 offset += sizeof(dummy_csum);
2827                 if (offset < sbi->s_desc_size)
2828                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2829                                              sbi->s_desc_size - offset);
2830
2831                 crc = csum32 & 0xFFFF;
2832                 goto out;
2833         }
2834
2835         /* old crc16 code */
2836         if (!ext4_has_feature_gdt_csum(sb))
2837                 return 0;
2838
2839         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2840         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2841         crc = crc16(crc, (__u8 *)gdp, offset);
2842         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2843         /* for checksum of struct ext4_group_desc do the rest...*/
2844         if (ext4_has_feature_64bit(sb) &&
2845             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2846                 crc = crc16(crc, (__u8 *)gdp + offset,
2847                             le16_to_cpu(sbi->s_es->s_desc_size) -
2848                                 offset);
2849
2850 out:
2851         return cpu_to_le16(crc);
2852 }
2853
2854 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2855                                 struct ext4_group_desc *gdp)
2856 {
2857         if (ext4_has_group_desc_csum(sb) &&
2858             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2859                 return 0;
2860
2861         return 1;
2862 }
2863
2864 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2865                               struct ext4_group_desc *gdp)
2866 {
2867         if (!ext4_has_group_desc_csum(sb))
2868                 return;
2869         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2870 }
2871
2872 /* Called at mount-time, super-block is locked */
2873 static int ext4_check_descriptors(struct super_block *sb,
2874                                   ext4_fsblk_t sb_block,
2875                                   ext4_group_t *first_not_zeroed)
2876 {
2877         struct ext4_sb_info *sbi = EXT4_SB(sb);
2878         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2879         ext4_fsblk_t last_block;
2880         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2881         ext4_fsblk_t block_bitmap;
2882         ext4_fsblk_t inode_bitmap;
2883         ext4_fsblk_t inode_table;
2884         int flexbg_flag = 0;
2885         ext4_group_t i, grp = sbi->s_groups_count;
2886
2887         if (ext4_has_feature_flex_bg(sb))
2888                 flexbg_flag = 1;
2889
2890         ext4_debug("Checking group descriptors");
2891
2892         for (i = 0; i < sbi->s_groups_count; i++) {
2893                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2894
2895                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2896                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2897                 else
2898                         last_block = first_block +
2899                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2900
2901                 if ((grp == sbi->s_groups_count) &&
2902                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2903                         grp = i;
2904
2905                 block_bitmap = ext4_block_bitmap(sb, gdp);
2906                 if (block_bitmap == sb_block) {
2907                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2908                                  "Block bitmap for group %u overlaps "
2909                                  "superblock", i);
2910                         if (!sb_rdonly(sb))
2911                                 return 0;
2912                 }
2913                 if (block_bitmap >= sb_block + 1 &&
2914                     block_bitmap <= last_bg_block) {
2915                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2916                                  "Block bitmap for group %u overlaps "
2917                                  "block group descriptors", i);
2918                         if (!sb_rdonly(sb))
2919                                 return 0;
2920                 }
2921                 if (block_bitmap < first_block || block_bitmap > last_block) {
2922                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2923                                "Block bitmap for group %u not in group "
2924                                "(block %llu)!", i, block_bitmap);
2925                         return 0;
2926                 }
2927                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2928                 if (inode_bitmap == sb_block) {
2929                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2930                                  "Inode bitmap for group %u overlaps "
2931                                  "superblock", i);
2932                         if (!sb_rdonly(sb))
2933                                 return 0;
2934                 }
2935                 if (inode_bitmap >= sb_block + 1 &&
2936                     inode_bitmap <= last_bg_block) {
2937                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2938                                  "Inode bitmap for group %u overlaps "
2939                                  "block group descriptors", i);
2940                         if (!sb_rdonly(sb))
2941                                 return 0;
2942                 }
2943                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2944                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2945                                "Inode bitmap for group %u not in group "
2946                                "(block %llu)!", i, inode_bitmap);
2947                         return 0;
2948                 }
2949                 inode_table = ext4_inode_table(sb, gdp);
2950                 if (inode_table == sb_block) {
2951                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2952                                  "Inode table for group %u overlaps "
2953                                  "superblock", i);
2954                         if (!sb_rdonly(sb))
2955                                 return 0;
2956                 }
2957                 if (inode_table >= sb_block + 1 &&
2958                     inode_table <= last_bg_block) {
2959                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2960                                  "Inode table for group %u overlaps "
2961                                  "block group descriptors", i);
2962                         if (!sb_rdonly(sb))
2963                                 return 0;
2964                 }
2965                 if (inode_table < first_block ||
2966                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2967                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2968                                "Inode table for group %u not in group "
2969                                "(block %llu)!", i, inode_table);
2970                         return 0;
2971                 }
2972                 ext4_lock_group(sb, i);
2973                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2974                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2975                                  "Checksum for group %u failed (%u!=%u)",
2976                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2977                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2978                         if (!sb_rdonly(sb)) {
2979                                 ext4_unlock_group(sb, i);
2980                                 return 0;
2981                         }
2982                 }
2983                 ext4_unlock_group(sb, i);
2984                 if (!flexbg_flag)
2985                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2986         }
2987         if (NULL != first_not_zeroed)
2988                 *first_not_zeroed = grp;
2989         return 1;
2990 }
2991
2992 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2993  * the superblock) which were deleted from all directories, but held open by
2994  * a process at the time of a crash.  We walk the list and try to delete these
2995  * inodes at recovery time (only with a read-write filesystem).
2996  *
2997  * In order to keep the orphan inode chain consistent during traversal (in
2998  * case of crash during recovery), we link each inode into the superblock
2999  * orphan list_head and handle it the same way as an inode deletion during
3000  * normal operation (which journals the operations for us).
3001  *
3002  * We only do an iget() and an iput() on each inode, which is very safe if we
3003  * accidentally point at an in-use or already deleted inode.  The worst that
3004  * can happen in this case is that we get a "bit already cleared" message from
3005  * ext4_free_inode().  The only reason we would point at a wrong inode is if
3006  * e2fsck was run on this filesystem, and it must have already done the orphan
3007  * inode cleanup for us, so we can safely abort without any further action.
3008  */
3009 static void ext4_orphan_cleanup(struct super_block *sb,
3010                                 struct ext4_super_block *es)
3011 {
3012         unsigned int s_flags = sb->s_flags;
3013         int ret, nr_orphans = 0, nr_truncates = 0;
3014 #ifdef CONFIG_QUOTA
3015         int quota_update = 0;
3016         int i;
3017 #endif
3018         if (!es->s_last_orphan) {
3019                 jbd_debug(4, "no orphan inodes to clean up\n");
3020                 return;
3021         }
3022
3023         if (bdev_read_only(sb->s_bdev)) {
3024                 ext4_msg(sb, KERN_ERR, "write access "
3025                         "unavailable, skipping orphan cleanup");
3026                 return;
3027         }
3028
3029         /* Check if feature set would not allow a r/w mount */
3030         if (!ext4_feature_set_ok(sb, 0)) {
3031                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
3032                          "unknown ROCOMPAT features");
3033                 return;
3034         }
3035
3036         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
3037                 /* don't clear list on RO mount w/ errors */
3038                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
3039                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
3040                                   "clearing orphan list.\n");
3041                         es->s_last_orphan = 0;
3042                 }
3043                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
3044                 return;
3045         }
3046
3047         if (s_flags & SB_RDONLY) {
3048                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
3049                 sb->s_flags &= ~SB_RDONLY;
3050         }
3051 #ifdef CONFIG_QUOTA
3052         /*
3053          * Turn on quotas which were not enabled for read-only mounts if
3054          * filesystem has quota feature, so that they are updated correctly.
3055          */
3056         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
3057                 int ret = ext4_enable_quotas(sb);
3058
3059                 if (!ret)
3060                         quota_update = 1;
3061                 else
3062                         ext4_msg(sb, KERN_ERR,
3063                                 "Cannot turn on quotas: error %d", ret);
3064         }
3065
3066         /* Turn on journaled quotas used for old sytle */
3067         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3068                 if (EXT4_SB(sb)->s_qf_names[i]) {
3069                         int ret = ext4_quota_on_mount(sb, i);
3070
3071                         if (!ret)
3072                                 quota_update = 1;
3073                         else
3074                                 ext4_msg(sb, KERN_ERR,
3075                                         "Cannot turn on journaled "
3076                                         "quota: type %d: error %d", i, ret);
3077                 }
3078         }
3079 #endif
3080
3081         while (es->s_last_orphan) {
3082                 struct inode *inode;
3083
3084                 /*
3085                  * We may have encountered an error during cleanup; if
3086                  * so, skip the rest.
3087                  */
3088                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
3089                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
3090                         es->s_last_orphan = 0;
3091                         break;
3092                 }
3093
3094                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
3095                 if (IS_ERR(inode)) {
3096                         es->s_last_orphan = 0;
3097                         break;
3098                 }
3099
3100                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
3101                 dquot_initialize(inode);
3102                 if (inode->i_nlink) {
3103                         if (test_opt(sb, DEBUG))
3104                                 ext4_msg(sb, KERN_DEBUG,
3105                                         "%s: truncating inode %lu to %lld bytes",
3106                                         __func__, inode->i_ino, inode->i_size);
3107                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
3108                                   inode->i_ino, inode->i_size);
3109                         inode_lock(inode);
3110                         truncate_inode_pages(inode->i_mapping, inode->i_size);
3111                         ret = ext4_truncate(inode);
3112                         if (ret) {
3113                                 /*
3114                                  * We need to clean up the in-core orphan list
3115                                  * manually if ext4_truncate() failed to get a
3116                                  * transaction handle.
3117                                  */
3118                                 ext4_orphan_del(NULL, inode);
3119                                 ext4_std_error(inode->i_sb, ret);
3120                         }
3121                         inode_unlock(inode);
3122                         nr_truncates++;
3123                 } else {
3124                         if (test_opt(sb, DEBUG))
3125                                 ext4_msg(sb, KERN_DEBUG,
3126                                         "%s: deleting unreferenced inode %lu",
3127                                         __func__, inode->i_ino);
3128                         jbd_debug(2, "deleting unreferenced inode %lu\n",
3129                                   inode->i_ino);
3130                         nr_orphans++;
3131                 }
3132                 iput(inode);  /* The delete magic happens here! */
3133         }
3134
3135 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
3136
3137         if (nr_orphans)
3138                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
3139                        PLURAL(nr_orphans));
3140         if (nr_truncates)
3141                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
3142                        PLURAL(nr_truncates));
3143 #ifdef CONFIG_QUOTA
3144         /* Turn off quotas if they were enabled for orphan cleanup */
3145         if (quota_update) {
3146                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3147                         if (sb_dqopt(sb)->files[i])
3148                                 dquot_quota_off(sb, i);
3149                 }
3150         }
3151 #endif
3152         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
3153 }
3154
3155 /*
3156  * Maximal extent format file size.
3157  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3158  * extent format containers, within a sector_t, and within i_blocks
3159  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3160  * so that won't be a limiting factor.
3161  *
3162  * However there is other limiting factor. We do store extents in the form
3163  * of starting block and length, hence the resulting length of the extent
3164  * covering maximum file size must fit into on-disk format containers as
3165  * well. Given that length is always by 1 unit bigger than max unit (because
3166  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3167  *
3168  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3169  */
3170 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3171 {
3172         loff_t res;
3173         loff_t upper_limit = MAX_LFS_FILESIZE;
3174
3175         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3176
3177         if (!has_huge_files) {
3178                 upper_limit = (1LL << 32) - 1;
3179
3180                 /* total blocks in file system block size */
3181                 upper_limit >>= (blkbits - 9);
3182                 upper_limit <<= blkbits;
3183         }
3184
3185         /*
3186          * 32-bit extent-start container, ee_block. We lower the maxbytes
3187          * by one fs block, so ee_len can cover the extent of maximum file
3188          * size
3189          */
3190         res = (1LL << 32) - 1;
3191         res <<= blkbits;
3192
3193         /* Sanity check against vm- & vfs- imposed limits */
3194         if (res > upper_limit)
3195                 res = upper_limit;
3196
3197         return res;
3198 }
3199
3200 /*
3201  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3202  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3203  * We need to be 1 filesystem block less than the 2^48 sector limit.
3204  */
3205 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3206 {
3207         loff_t res = EXT4_NDIR_BLOCKS;
3208         int meta_blocks;
3209         loff_t upper_limit;
3210         /* This is calculated to be the largest file size for a dense, block
3211          * mapped file such that the file's total number of 512-byte sectors,
3212          * including data and all indirect blocks, does not exceed (2^48 - 1).
3213          *
3214          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3215          * number of 512-byte sectors of the file.
3216          */
3217
3218         if (!has_huge_files) {
3219                 /*
3220                  * !has_huge_files or implies that the inode i_block field
3221                  * represents total file blocks in 2^32 512-byte sectors ==
3222                  * size of vfs inode i_blocks * 8
3223                  */
3224                 upper_limit = (1LL << 32) - 1;
3225
3226                 /* total blocks in file system block size */
3227                 upper_limit >>= (bits - 9);
3228
3229         } else {
3230                 /*
3231                  * We use 48 bit ext4_inode i_blocks
3232                  * With EXT4_HUGE_FILE_FL set the i_blocks
3233                  * represent total number of blocks in
3234                  * file system block size
3235                  */
3236                 upper_limit = (1LL << 48) - 1;
3237
3238         }
3239
3240         /* indirect blocks */
3241         meta_blocks = 1;
3242         /* double indirect blocks */
3243         meta_blocks += 1 + (1LL << (bits-2));
3244         /* tripple indirect blocks */
3245         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
3246
3247         upper_limit -= meta_blocks;
3248         upper_limit <<= bits;
3249
3250         res += 1LL << (bits-2);
3251         res += 1LL << (2*(bits-2));
3252         res += 1LL << (3*(bits-2));
3253         res <<= bits;
3254         if (res > upper_limit)
3255                 res = upper_limit;
3256
3257         if (res > MAX_LFS_FILESIZE)
3258                 res = MAX_LFS_FILESIZE;
3259
3260         return res;
3261 }
3262
3263 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3264                                    ext4_fsblk_t logical_sb_block, int nr)
3265 {
3266         struct ext4_sb_info *sbi = EXT4_SB(sb);
3267         ext4_group_t bg, first_meta_bg;
3268         int has_super = 0;
3269
3270         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3271
3272         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3273                 return logical_sb_block + nr + 1;
3274         bg = sbi->s_desc_per_block * nr;
3275         if (ext4_bg_has_super(sb, bg))
3276                 has_super = 1;
3277
3278         /*
3279          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3280          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3281          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3282          * compensate.
3283          */
3284         if (sb->s_blocksize == 1024 && nr == 0 &&
3285             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3286                 has_super++;
3287
3288         return (has_super + ext4_group_first_block_no(sb, bg));
3289 }
3290
3291 /**
3292  * ext4_get_stripe_size: Get the stripe size.
3293  * @sbi: In memory super block info
3294  *
3295  * If we have specified it via mount option, then
3296  * use the mount option value. If the value specified at mount time is
3297  * greater than the blocks per group use the super block value.
3298  * If the super block value is greater than blocks per group return 0.
3299  * Allocator needs it be less than blocks per group.
3300  *
3301  */
3302 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3303 {
3304         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3305         unsigned long stripe_width =
3306                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3307         int ret;
3308
3309         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3310                 ret = sbi->s_stripe;
3311         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3312                 ret = stripe_width;
3313         else if (stride && stride <= sbi->s_blocks_per_group)
3314                 ret = stride;
3315         else
3316                 ret = 0;
3317
3318         /*
3319          * If the stripe width is 1, this makes no sense and
3320          * we set it to 0 to turn off stripe handling code.
3321          */
3322         if (ret <= 1)
3323                 ret = 0;
3324
3325         return ret;
3326 }
3327
3328 /*
3329  * Check whether this filesystem can be mounted based on
3330  * the features present and the RDONLY/RDWR mount requested.
3331  * Returns 1 if this filesystem can be mounted as requested,
3332  * 0 if it cannot be.
3333  */
3334 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
3335 {
3336         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3337                 ext4_msg(sb, KERN_ERR,
3338                         "Couldn't mount because of "
3339                         "unsupported optional features (%x)",
3340                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3341                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3342                 return 0;
3343         }
3344
3345 #ifndef CONFIG_UNICODE
3346         if (ext4_has_feature_casefold(sb)) {
3347                 ext4_msg(sb, KERN_ERR,
3348                          "Filesystem with casefold feature cannot be "
3349                          "mounted without CONFIG_UNICODE");
3350                 return 0;
3351         }
3352 #endif
3353
3354         if (readonly)
3355                 return 1;
3356
3357         if (ext4_has_feature_readonly(sb)) {
3358                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3359                 sb->s_flags |= SB_RDONLY;
3360                 return 1;
3361         }
3362
3363         /* Check that feature set is OK for a read-write mount */
3364         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3365                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3366                          "unsupported optional features (%x)",
3367                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3368                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3369                 return 0;
3370         }
3371         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3372                 ext4_msg(sb, KERN_ERR,
3373                          "Can't support bigalloc feature without "
3374                          "extents feature\n");
3375                 return 0;
3376         }
3377
3378 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3379         if (!readonly && (ext4_has_feature_quota(sb) ||
3380                           ext4_has_feature_project(sb))) {
3381                 ext4_msg(sb, KERN_ERR,
3382                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3383                 return 0;
3384         }
3385 #endif  /* CONFIG_QUOTA */
3386         return 1;
3387 }
3388
3389 /*
3390  * This function is called once a day if we have errors logged
3391  * on the file system
3392  */
3393 static void print_daily_error_info(struct timer_list *t)
3394 {
3395         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3396         struct super_block *sb = sbi->s_sb;
3397         struct ext4_super_block *es = sbi->s_es;
3398
3399         if (es->s_error_count)
3400                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3401                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3402                          le32_to_cpu(es->s_error_count));
3403         if (es->s_first_error_time) {
3404                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3405                        sb->s_id,
3406                        ext4_get_tstamp(es, s_first_error_time),
3407                        (int) sizeof(es->s_first_error_func),
3408                        es->s_first_error_func,
3409                        le32_to_cpu(es->s_first_error_line));
3410                 if (es->s_first_error_ino)
3411                         printk(KERN_CONT ": inode %u",
3412                                le32_to_cpu(es->s_first_error_ino));
3413                 if (es->s_first_error_block)
3414                         printk(KERN_CONT ": block %llu", (unsigned long long)
3415                                le64_to_cpu(es->s_first_error_block));
3416                 printk(KERN_CONT "\n");
3417         }
3418         if (es->s_last_error_time) {
3419                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3420                        sb->s_id,
3421                        ext4_get_tstamp(es, s_last_error_time),
3422                        (int) sizeof(es->s_last_error_func),
3423                        es->s_last_error_func,
3424                        le32_to_cpu(es->s_last_error_line));
3425                 if (es->s_last_error_ino)
3426                         printk(KERN_CONT ": inode %u",
3427                                le32_to_cpu(es->s_last_error_ino));
3428                 if (es->s_last_error_block)
3429                         printk(KERN_CONT ": block %llu", (unsigned long long)
3430                                le64_to_cpu(es->s_last_error_block));
3431                 printk(KERN_CONT "\n");
3432         }
3433         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3434 }
3435
3436 /* Find next suitable group and run ext4_init_inode_table */
3437 static int ext4_run_li_request(struct ext4_li_request *elr)
3438 {
3439         struct ext4_group_desc *gdp = NULL;
3440         struct super_block *sb = elr->lr_super;
3441         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3442         ext4_group_t group = elr->lr_next_group;
3443         unsigned long timeout = 0;
3444         unsigned int prefetch_ios = 0;
3445         int ret = 0;
3446
3447         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3448                 elr->lr_next_group = ext4_mb_prefetch(sb, group,
3449                                 EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3450                 if (prefetch_ios)
3451                         ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3452                                               prefetch_ios);
3453                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3454                                             prefetch_ios);
3455                 if (group >= elr->lr_next_group) {
3456                         ret = 1;
3457                         if (elr->lr_first_not_zeroed != ngroups &&
3458                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3459                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3460                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3461                                 ret = 0;
3462                         }
3463                 }
3464                 return ret;
3465         }
3466
3467         for (; group < ngroups; group++) {
3468                 gdp = ext4_get_group_desc(sb, group, NULL);
3469                 if (!gdp) {
3470                         ret = 1;
3471                         break;
3472                 }
3473
3474                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3475                         break;
3476         }
3477
3478         if (group >= ngroups)
3479                 ret = 1;
3480
3481         if (!ret) {
3482                 timeout = jiffies;
3483                 ret = ext4_init_inode_table(sb, group,
3484                                             elr->lr_timeout ? 0 : 1);
3485                 trace_ext4_lazy_itable_init(sb, group);
3486                 if (elr->lr_timeout == 0) {
3487                         timeout = (jiffies - timeout) *
3488                                 EXT4_SB(elr->lr_super)->s_li_wait_mult;
3489                         elr->lr_timeout = timeout;
3490                 }
3491                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3492                 elr->lr_next_group = group + 1;
3493         }
3494         return ret;
3495 }
3496
3497 /*
3498  * Remove lr_request from the list_request and free the
3499  * request structure. Should be called with li_list_mtx held
3500  */
3501 static void ext4_remove_li_request(struct ext4_li_request *elr)
3502 {
3503         if (!elr)
3504                 return;
3505
3506         list_del(&elr->lr_request);
3507         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3508         kfree(elr);
3509 }
3510
3511 static void ext4_unregister_li_request(struct super_block *sb)
3512 {
3513         mutex_lock(&ext4_li_mtx);
3514         if (!ext4_li_info) {
3515                 mutex_unlock(&ext4_li_mtx);
3516                 return;
3517         }
3518
3519         mutex_lock(&ext4_li_info->li_list_mtx);
3520         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3521         mutex_unlock(&ext4_li_info->li_list_mtx);
3522         mutex_unlock(&ext4_li_mtx);
3523 }
3524
3525 static struct task_struct *ext4_lazyinit_task;
3526
3527 /*
3528  * This is the function where ext4lazyinit thread lives. It walks
3529  * through the request list searching for next scheduled filesystem.
3530  * When such a fs is found, run the lazy initialization request
3531  * (ext4_rn_li_request) and keep track of the time spend in this
3532  * function. Based on that time we compute next schedule time of
3533  * the request. When walking through the list is complete, compute
3534  * next waking time and put itself into sleep.
3535  */
3536 static int ext4_lazyinit_thread(void *arg)
3537 {
3538         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3539         struct list_head *pos, *n;
3540         struct ext4_li_request *elr;
3541         unsigned long next_wakeup, cur;
3542
3543         BUG_ON(NULL == eli);
3544
3545 cont_thread:
3546         while (true) {
3547                 next_wakeup = MAX_JIFFY_OFFSET;
3548
3549                 mutex_lock(&eli->li_list_mtx);
3550                 if (list_empty(&eli->li_request_list)) {
3551                         mutex_unlock(&eli->li_list_mtx);
3552                         goto exit_thread;
3553                 }
3554                 list_for_each_safe(pos, n, &eli->li_request_list) {
3555                         int err = 0;
3556                         int progress = 0;
3557                         elr = list_entry(pos, struct ext4_li_request,
3558                                          lr_request);
3559
3560                         if (time_before(jiffies, elr->lr_next_sched)) {
3561                                 if (time_before(elr->lr_next_sched, next_wakeup))
3562                                         next_wakeup = elr->lr_next_sched;
3563                                 continue;
3564                         }
3565                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3566                                 if (sb_start_write_trylock(elr->lr_super)) {
3567                                         progress = 1;
3568                                         /*
3569                                          * We hold sb->s_umount, sb can not
3570                                          * be removed from the list, it is
3571                                          * now safe to drop li_list_mtx
3572                                          */
3573                                         mutex_unlock(&eli->li_list_mtx);
3574                                         err = ext4_run_li_request(elr);
3575                                         sb_end_write(elr->lr_super);
3576                                         mutex_lock(&eli->li_list_mtx);
3577                                         n = pos->next;
3578                                 }
3579                                 up_read((&elr->lr_super->s_umount));
3580                         }
3581                         /* error, remove the lazy_init job */
3582                         if (err) {
3583                                 ext4_remove_li_request(elr);
3584                                 continue;
3585                         }
3586                         if (!progress) {
3587                                 elr->lr_next_sched = jiffies +
3588                                         (prandom_u32()
3589                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3590                         }
3591                         if (time_before(elr->lr_next_sched, next_wakeup))
3592                                 next_wakeup = elr->lr_next_sched;
3593                 }
3594                 mutex_unlock(&eli->li_list_mtx);
3595
3596                 try_to_freeze();
3597
3598                 cur = jiffies;
3599                 if ((time_after_eq(cur, next_wakeup)) ||
3600                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3601                         cond_resched();
3602                         continue;
3603                 }
3604
3605                 schedule_timeout_interruptible(next_wakeup - cur);
3606
3607                 if (kthread_should_stop()) {
3608                         ext4_clear_request_list();
3609                         goto exit_thread;
3610                 }
3611         }
3612
3613 exit_thread:
3614         /*
3615          * It looks like the request list is empty, but we need
3616          * to check it under the li_list_mtx lock, to prevent any
3617          * additions into it, and of course we should lock ext4_li_mtx
3618          * to atomically free the list and ext4_li_info, because at
3619          * this point another ext4 filesystem could be registering
3620          * new one.
3621          */
3622         mutex_lock(&ext4_li_mtx);
3623         mutex_lock(&eli->li_list_mtx);
3624         if (!list_empty(&eli->li_request_list)) {
3625                 mutex_unlock(&eli->li_list_mtx);
3626                 mutex_unlock(&ext4_li_mtx);
3627                 goto cont_thread;
3628         }
3629         mutex_unlock(&eli->li_list_mtx);
3630         kfree(ext4_li_info);
3631         ext4_li_info = NULL;
3632         mutex_unlock(&ext4_li_mtx);
3633
3634         return 0;
3635 }
3636
3637 static void ext4_clear_request_list(void)
3638 {
3639         struct list_head *pos, *n;
3640         struct ext4_li_request *elr;
3641
3642         mutex_lock(&ext4_li_info->li_list_mtx);
3643         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3644                 elr = list_entry(pos, struct ext4_li_request,
3645                                  lr_request);
3646                 ext4_remove_li_request(elr);
3647         }
3648         mutex_unlock(&ext4_li_info->li_list_mtx);
3649 }
3650
3651 static int ext4_run_lazyinit_thread(void)
3652 {
3653         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3654                                          ext4_li_info, "ext4lazyinit");
3655         if (IS_ERR(ext4_lazyinit_task)) {
3656                 int err = PTR_ERR(ext4_lazyinit_task);
3657                 ext4_clear_request_list();
3658                 kfree(ext4_li_info);
3659                 ext4_li_info = NULL;
3660                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3661                                  "initialization thread\n",
3662                                  err);
3663                 return err;
3664         }
3665         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3666         return 0;
3667 }
3668
3669 /*
3670  * Check whether it make sense to run itable init. thread or not.
3671  * If there is at least one uninitialized inode table, return
3672  * corresponding group number, else the loop goes through all
3673  * groups and return total number of groups.
3674  */
3675 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3676 {
3677         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3678         struct ext4_group_desc *gdp = NULL;
3679
3680         if (!ext4_has_group_desc_csum(sb))
3681                 return ngroups;
3682
3683         for (group = 0; group < ngroups; group++) {
3684                 gdp = ext4_get_group_desc(sb, group, NULL);
3685                 if (!gdp)
3686                         continue;
3687
3688                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3689                         break;
3690         }
3691
3692         return group;
3693 }
3694
3695 static int ext4_li_info_new(void)
3696 {
3697         struct ext4_lazy_init *eli = NULL;
3698
3699         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3700         if (!eli)
3701                 return -ENOMEM;
3702
3703         INIT_LIST_HEAD(&eli->li_request_list);
3704         mutex_init(&eli->li_list_mtx);
3705
3706         eli->li_state |= EXT4_LAZYINIT_QUIT;
3707
3708         ext4_li_info = eli;
3709
3710         return 0;
3711 }
3712
3713 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3714                                             ext4_group_t start)
3715 {
3716         struct ext4_li_request *elr;
3717
3718         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3719         if (!elr)
3720                 return NULL;
3721
3722         elr->lr_super = sb;
3723         elr->lr_first_not_zeroed = start;
3724         if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS)) {
3725                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3726                 elr->lr_next_group = start;
3727         } else {
3728                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3729         }
3730
3731         /*
3732          * Randomize first schedule time of the request to
3733          * spread the inode table initialization requests
3734          * better.
3735          */
3736         elr->lr_next_sched = jiffies + (prandom_u32() %
3737                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3738         return elr;
3739 }
3740
3741 int ext4_register_li_request(struct super_block *sb,
3742                              ext4_group_t first_not_zeroed)
3743 {
3744         struct ext4_sb_info *sbi = EXT4_SB(sb);
3745         struct ext4_li_request *elr = NULL;
3746         ext4_group_t ngroups = sbi->s_groups_count;
3747         int ret = 0;
3748
3749         mutex_lock(&ext4_li_mtx);
3750         if (sbi->s_li_request != NULL) {
3751                 /*
3752                  * Reset timeout so it can be computed again, because
3753                  * s_li_wait_mult might have changed.
3754                  */
3755                 sbi->s_li_request->lr_timeout = 0;
3756                 goto out;
3757         }
3758
3759         if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS) &&
3760             (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3761              !test_opt(sb, INIT_INODE_TABLE)))
3762                 goto out;
3763
3764         elr = ext4_li_request_new(sb, first_not_zeroed);
3765         if (!elr) {
3766                 ret = -ENOMEM;
3767                 goto out;
3768         }
3769
3770         if (NULL == ext4_li_info) {
3771                 ret = ext4_li_info_new();
3772                 if (ret)
3773                         goto out;
3774         }
3775
3776         mutex_lock(&ext4_li_info->li_list_mtx);
3777         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3778         mutex_unlock(&ext4_li_info->li_list_mtx);
3779
3780         sbi->s_li_request = elr;
3781         /*
3782          * set elr to NULL here since it has been inserted to
3783          * the request_list and the removal and free of it is
3784          * handled by ext4_clear_request_list from now on.
3785          */
3786         elr = NULL;
3787
3788         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3789                 ret = ext4_run_lazyinit_thread();
3790                 if (ret)
3791                         goto out;
3792         }
3793 out:
3794         mutex_unlock(&ext4_li_mtx);
3795         if (ret)
3796                 kfree(elr);
3797         return ret;
3798 }
3799
3800 /*
3801  * We do not need to lock anything since this is called on
3802  * module unload.
3803  */
3804 static void ext4_destroy_lazyinit_thread(void)
3805 {
3806         /*
3807          * If thread exited earlier
3808          * there's nothing to be done.
3809          */
3810         if (!ext4_li_info || !ext4_lazyinit_task)
3811                 return;
3812
3813         kthread_stop(ext4_lazyinit_task);
3814 }
3815
3816 static int set_journal_csum_feature_set(struct super_block *sb)
3817 {
3818         int ret = 1;
3819         int compat, incompat;
3820         struct ext4_sb_info *sbi = EXT4_SB(sb);
3821
3822         if (ext4_has_metadata_csum(sb)) {
3823                 /* journal checksum v3 */
3824                 compat = 0;
3825                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3826         } else {
3827                 /* journal checksum v1 */
3828                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3829                 incompat = 0;
3830         }
3831
3832         jbd2_journal_clear_features(sbi->s_journal,
3833                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3834                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3835                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3836         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3837                 ret = jbd2_journal_set_features(sbi->s_journal,
3838                                 compat, 0,
3839                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3840                                 incompat);
3841         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3842                 ret = jbd2_journal_set_features(sbi->s_journal,
3843                                 compat, 0,
3844                                 incompat);
3845                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3846                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3847         } else {
3848                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3849                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3850         }
3851
3852         return ret;
3853 }
3854
3855 /*
3856  * Note: calculating the overhead so we can be compatible with
3857  * historical BSD practice is quite difficult in the face of
3858  * clusters/bigalloc.  This is because multiple metadata blocks from
3859  * different block group can end up in the same allocation cluster.
3860  * Calculating the exact overhead in the face of clustered allocation
3861  * requires either O(all block bitmaps) in memory or O(number of block
3862  * groups**2) in time.  We will still calculate the superblock for
3863  * older file systems --- and if we come across with a bigalloc file
3864  * system with zero in s_overhead_clusters the estimate will be close to
3865  * correct especially for very large cluster sizes --- but for newer
3866  * file systems, it's better to calculate this figure once at mkfs
3867  * time, and store it in the superblock.  If the superblock value is
3868  * present (even for non-bigalloc file systems), we will use it.
3869  */
3870 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3871                           char *buf)
3872 {
3873         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3874         struct ext4_group_desc  *gdp;
3875         ext4_fsblk_t            first_block, last_block, b;
3876         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3877         int                     s, j, count = 0;
3878
3879         if (!ext4_has_feature_bigalloc(sb))
3880                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3881                         sbi->s_itb_per_group + 2);
3882
3883         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3884                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3885         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3886         for (i = 0; i < ngroups; i++) {
3887                 gdp = ext4_get_group_desc(sb, i, NULL);
3888                 b = ext4_block_bitmap(sb, gdp);
3889                 if (b >= first_block && b <= last_block) {
3890                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3891                         count++;
3892                 }
3893                 b = ext4_inode_bitmap(sb, gdp);
3894                 if (b >= first_block && b <= last_block) {
3895                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3896                         count++;
3897                 }
3898                 b = ext4_inode_table(sb, gdp);
3899                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3900                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3901                                 int c = EXT4_B2C(sbi, b - first_block);
3902                                 ext4_set_bit(c, buf);
3903                                 count++;
3904                         }
3905                 if (i != grp)
3906                         continue;
3907                 s = 0;
3908                 if (ext4_bg_has_super(sb, grp)) {
3909                         ext4_set_bit(s++, buf);
3910                         count++;
3911                 }
3912                 j = ext4_bg_num_gdb(sb, grp);
3913                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3914                         ext4_error(sb, "Invalid number of block group "
3915                                    "descriptor blocks: %d", j);
3916                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3917                 }
3918                 count += j;
3919                 for (; j > 0; j--)
3920                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3921         }
3922         if (!count)
3923                 return 0;
3924         return EXT4_CLUSTERS_PER_GROUP(sb) -
3925                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3926 }
3927
3928 /*
3929  * Compute the overhead and stash it in sbi->s_overhead
3930  */
3931 int ext4_calculate_overhead(struct super_block *sb)
3932 {
3933         struct ext4_sb_info *sbi = EXT4_SB(sb);
3934         struct ext4_super_block *es = sbi->s_es;
3935         struct inode *j_inode;
3936         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3937         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3938         ext4_fsblk_t overhead = 0;
3939         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3940
3941         if (!buf)
3942                 return -ENOMEM;
3943
3944         /*
3945          * Compute the overhead (FS structures).  This is constant
3946          * for a given filesystem unless the number of block groups
3947          * changes so we cache the previous value until it does.
3948          */
3949
3950         /*
3951          * All of the blocks before first_data_block are overhead
3952          */
3953         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3954
3955         /*
3956          * Add the overhead found in each block group
3957          */
3958         for (i = 0; i < ngroups; i++) {
3959                 int blks;
3960
3961                 blks = count_overhead(sb, i, buf);
3962                 overhead += blks;
3963                 if (blks)
3964                         memset(buf, 0, PAGE_SIZE);
3965                 cond_resched();
3966         }
3967
3968         /*
3969          * Add the internal journal blocks whether the journal has been
3970          * loaded or not
3971          */
3972         if (sbi->s_journal && !sbi->s_journal_bdev)
3973                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
3974         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3975                 /* j_inum for internal journal is non-zero */
3976                 j_inode = ext4_get_journal_inode(sb, j_inum);
3977                 if (j_inode) {
3978                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3979                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3980                         iput(j_inode);
3981                 } else {
3982                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3983                 }
3984         }
3985         sbi->s_overhead = overhead;
3986         smp_wmb();
3987         free_page((unsigned long) buf);
3988         return 0;
3989 }
3990
3991 static void ext4_set_resv_clusters(struct super_block *sb)
3992 {
3993         ext4_fsblk_t resv_clusters;
3994         struct ext4_sb_info *sbi = EXT4_SB(sb);
3995
3996         /*
3997          * There's no need to reserve anything when we aren't using extents.
3998          * The space estimates are exact, there are no unwritten extents,
3999          * hole punching doesn't need new metadata... This is needed especially
4000          * to keep ext2/3 backward compatibility.
4001          */
4002         if (!ext4_has_feature_extents(sb))
4003                 return;
4004         /*
4005          * By default we reserve 2% or 4096 clusters, whichever is smaller.
4006          * This should cover the situations where we can not afford to run
4007          * out of space like for example punch hole, or converting
4008          * unwritten extents in delalloc path. In most cases such
4009          * allocation would require 1, or 2 blocks, higher numbers are
4010          * very rare.
4011          */
4012         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4013                          sbi->s_cluster_bits);
4014
4015         do_div(resv_clusters, 50);
4016         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4017
4018         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4019 }
4020
4021 static const char *ext4_quota_mode(struct super_block *sb)
4022 {
4023 #ifdef CONFIG_QUOTA
4024         if (!ext4_quota_capable(sb))
4025                 return "none";
4026
4027         if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
4028                 return "journalled";
4029         else
4030                 return "writeback";
4031 #else
4032         return "disabled";
4033 #endif
4034 }
4035
4036 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
4037 {
4038         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
4039         char *orig_data = kstrdup(data, GFP_KERNEL);
4040         struct buffer_head *bh, **group_desc;
4041         struct ext4_super_block *es = NULL;
4042         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4043         struct flex_groups **flex_groups;
4044         ext4_fsblk_t block;
4045         ext4_fsblk_t sb_block = get_sb_block(&data);
4046         ext4_fsblk_t logical_sb_block;
4047         unsigned long offset = 0;
4048         unsigned long def_mount_opts;
4049         struct inode *root;
4050         const char *descr;
4051         int ret = -ENOMEM;
4052         int blocksize, clustersize;
4053         unsigned int db_count;
4054         unsigned int i;
4055         int needs_recovery, has_huge_files;
4056         __u64 blocks_count;
4057         int err = 0;
4058         ext4_group_t first_not_zeroed;
4059         struct ext4_parsed_options parsed_opts;
4060
4061         /* Set defaults for the variables that will be set during parsing */
4062         parsed_opts.journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4063         parsed_opts.journal_devnum = 0;
4064         parsed_opts.mb_optimize_scan = DEFAULT_MB_OPTIMIZE_SCAN;
4065
4066         if ((data && !orig_data) || !sbi)
4067                 goto out_free_base;
4068
4069         sbi->s_daxdev = dax_dev;
4070         sbi->s_blockgroup_lock =
4071                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4072         if (!sbi->s_blockgroup_lock)
4073                 goto out_free_base;
4074
4075         sb->s_fs_info = sbi;
4076         sbi->s_sb = sb;
4077         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
4078         sbi->s_sb_block = sb_block;
4079         sbi->s_sectors_written_start =
4080                 part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
4081
4082         /* Cleanup superblock name */
4083         strreplace(sb->s_id, '/', '!');
4084
4085         /* -EINVAL is default */
4086         ret = -EINVAL;
4087         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
4088         if (!blocksize) {
4089                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
4090                 goto out_fail;
4091         }
4092
4093         /*
4094          * The ext4 superblock will not be buffer aligned for other than 1kB
4095          * block sizes.  We need to calculate the offset from buffer start.
4096          */
4097         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
4098                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4099                 offset = do_div(logical_sb_block, blocksize);
4100         } else {
4101                 logical_sb_block = sb_block;
4102         }
4103
4104         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4105         if (IS_ERR(bh)) {
4106                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
4107                 ret = PTR_ERR(bh);
4108                 goto out_fail;
4109         }
4110         /*
4111          * Note: s_es must be initialized as soon as possible because
4112          *       some ext4 macro-instructions depend on its value
4113          */
4114         es = (struct ext4_super_block *) (bh->b_data + offset);
4115         sbi->s_es = es;
4116         sb->s_magic = le16_to_cpu(es->s_magic);
4117         if (sb->s_magic != EXT4_SUPER_MAGIC)
4118                 goto cantfind_ext4;
4119         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
4120
4121         /* Warn if metadata_csum and gdt_csum are both set. */
4122         if (ext4_has_feature_metadata_csum(sb) &&
4123             ext4_has_feature_gdt_csum(sb))
4124                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4125                              "redundant flags; please run fsck.");
4126
4127         /* Check for a known checksum algorithm */
4128         if (!ext4_verify_csum_type(sb, es)) {
4129                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4130                          "unknown checksum algorithm.");
4131                 silent = 1;
4132                 goto cantfind_ext4;
4133         }
4134
4135         /* Load the checksum driver */
4136         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4137         if (IS_ERR(sbi->s_chksum_driver)) {
4138                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4139                 ret = PTR_ERR(sbi->s_chksum_driver);
4140                 sbi->s_chksum_driver = NULL;
4141                 goto failed_mount;
4142         }
4143
4144         /* Check superblock checksum */
4145         if (!ext4_superblock_csum_verify(sb, es)) {
4146                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4147                          "invalid superblock checksum.  Run e2fsck?");
4148                 silent = 1;
4149                 ret = -EFSBADCRC;
4150                 goto cantfind_ext4;
4151         }
4152
4153         /* Precompute checksum seed for all metadata */
4154         if (ext4_has_feature_csum_seed(sb))
4155                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4156         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4157                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4158                                                sizeof(es->s_uuid));
4159
4160         /* Set defaults before we parse the mount options */
4161         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4162         set_opt(sb, INIT_INODE_TABLE);
4163         if (def_mount_opts & EXT4_DEFM_DEBUG)
4164                 set_opt(sb, DEBUG);
4165         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4166                 set_opt(sb, GRPID);
4167         if (def_mount_opts & EXT4_DEFM_UID16)
4168                 set_opt(sb, NO_UID32);
4169         /* xattr user namespace & acls are now defaulted on */
4170         set_opt(sb, XATTR_USER);
4171 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4172         set_opt(sb, POSIX_ACL);
4173 #endif
4174         if (ext4_has_feature_fast_commit(sb))
4175                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4176         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4177         if (ext4_has_metadata_csum(sb))
4178                 set_opt(sb, JOURNAL_CHECKSUM);
4179
4180         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4181                 set_opt(sb, JOURNAL_DATA);
4182         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4183                 set_opt(sb, ORDERED_DATA);
4184         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4185                 set_opt(sb, WRITEBACK_DATA);
4186
4187         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
4188                 set_opt(sb, ERRORS_PANIC);
4189         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
4190                 set_opt(sb, ERRORS_CONT);
4191         else
4192                 set_opt(sb, ERRORS_RO);
4193         /* block_validity enabled by default; disable with noblock_validity */
4194         set_opt(sb, BLOCK_VALIDITY);
4195         if (def_mount_opts & EXT4_DEFM_DISCARD)
4196                 set_opt(sb, DISCARD);
4197
4198         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
4199         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
4200         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
4201         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
4202         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
4203
4204         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4205                 set_opt(sb, BARRIER);
4206
4207         /*
4208          * enable delayed allocation by default
4209          * Use -o nodelalloc to turn it off
4210          */
4211         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4212             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4213                 set_opt(sb, DELALLOC);
4214
4215         /*
4216          * set default s_li_wait_mult for lazyinit, for the case there is
4217          * no mount option specified.
4218          */
4219         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
4220
4221         if (le32_to_cpu(es->s_log_block_size) >
4222             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4223                 ext4_msg(sb, KERN_ERR,
4224                          "Invalid log block size: %u",
4225                          le32_to_cpu(es->s_log_block_size));
4226                 goto failed_mount;
4227         }
4228         if (le32_to_cpu(es->s_log_cluster_size) >
4229             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4230                 ext4_msg(sb, KERN_ERR,
4231                          "Invalid log cluster size: %u",
4232                          le32_to_cpu(es->s_log_cluster_size));
4233                 goto failed_mount;
4234         }
4235
4236         blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
4237
4238         if (blocksize == PAGE_SIZE)
4239                 set_opt(sb, DIOREAD_NOLOCK);
4240
4241         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4242                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4243                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4244         } else {
4245                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4246                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4247                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4248                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4249                                  sbi->s_first_ino);
4250                         goto failed_mount;
4251                 }
4252                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4253                     (!is_power_of_2(sbi->s_inode_size)) ||
4254                     (sbi->s_inode_size > blocksize)) {
4255                         ext4_msg(sb, KERN_ERR,
4256                                "unsupported inode size: %d",
4257                                sbi->s_inode_size);
4258                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
4259                         goto failed_mount;
4260                 }
4261                 /*
4262                  * i_atime_extra is the last extra field available for
4263                  * [acm]times in struct ext4_inode. Checking for that
4264                  * field should suffice to ensure we have extra space
4265                  * for all three.
4266                  */
4267                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4268                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4269                         sb->s_time_gran = 1;
4270                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4271                 } else {
4272                         sb->s_time_gran = NSEC_PER_SEC;
4273                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4274                 }
4275                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4276         }
4277         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4278                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4279                         EXT4_GOOD_OLD_INODE_SIZE;
4280                 if (ext4_has_feature_extra_isize(sb)) {
4281                         unsigned v, max = (sbi->s_inode_size -
4282                                            EXT4_GOOD_OLD_INODE_SIZE);
4283
4284                         v = le16_to_cpu(es->s_want_extra_isize);
4285                         if (v > max) {
4286                                 ext4_msg(sb, KERN_ERR,
4287                                          "bad s_want_extra_isize: %d", v);
4288                                 goto failed_mount;
4289                         }
4290                         if (sbi->s_want_extra_isize < v)
4291                                 sbi->s_want_extra_isize = v;
4292
4293                         v = le16_to_cpu(es->s_min_extra_isize);
4294                         if (v > max) {
4295                                 ext4_msg(sb, KERN_ERR,
4296                                          "bad s_min_extra_isize: %d", v);
4297                                 goto failed_mount;
4298                         }
4299                         if (sbi->s_want_extra_isize < v)
4300                                 sbi->s_want_extra_isize = v;
4301                 }
4302         }
4303
4304         if (sbi->s_es->s_mount_opts[0]) {
4305                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
4306                                               sizeof(sbi->s_es->s_mount_opts),
4307                                               GFP_KERNEL);
4308                 if (!s_mount_opts)
4309                         goto failed_mount;
4310                 if (!parse_options(s_mount_opts, sb, &parsed_opts, 0)) {
4311                         ext4_msg(sb, KERN_WARNING,
4312                                  "failed to parse options in superblock: %s",
4313                                  s_mount_opts);
4314                 }
4315                 kfree(s_mount_opts);
4316         }
4317         sbi->s_def_mount_opt = sbi->s_mount_opt;
4318         if (!parse_options((char *) data, sb, &parsed_opts, 0))
4319                 goto failed_mount;
4320
4321 #ifdef CONFIG_UNICODE
4322         if (ext4_has_feature_casefold(sb) && !sb->s_encoding) {
4323                 const struct ext4_sb_encodings *encoding_info;
4324                 struct unicode_map *encoding;
4325                 __u16 encoding_flags;
4326
4327                 if (ext4_sb_read_encoding(es, &encoding_info,
4328                                           &encoding_flags)) {
4329                         ext4_msg(sb, KERN_ERR,
4330                                  "Encoding requested by superblock is unknown");
4331                         goto failed_mount;
4332                 }
4333
4334                 encoding = utf8_load(encoding_info->version);
4335                 if (IS_ERR(encoding)) {
4336                         ext4_msg(sb, KERN_ERR,
4337                                  "can't mount with superblock charset: %s-%s "
4338                                  "not supported by the kernel. flags: 0x%x.",
4339                                  encoding_info->name, encoding_info->version,
4340                                  encoding_flags);
4341                         goto failed_mount;
4342                 }
4343                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4344                          "%s-%s with flags 0x%hx", encoding_info->name,
4345                          encoding_info->version?:"\b", encoding_flags);
4346
4347                 sb->s_encoding = encoding;
4348                 sb->s_encoding_flags = encoding_flags;
4349         }
4350 #endif
4351
4352         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4353                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, O_DIRECT and fast_commit support!\n");
4354                 /* can't mount with both data=journal and dioread_nolock. */
4355                 clear_opt(sb, DIOREAD_NOLOCK);
4356                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4357                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4358                         ext4_msg(sb, KERN_ERR, "can't mount with "
4359                                  "both data=journal and delalloc");
4360                         goto failed_mount;
4361                 }
4362                 if (test_opt(sb, DAX_ALWAYS)) {
4363                         ext4_msg(sb, KERN_ERR, "can't mount with "
4364                                  "both data=journal and dax");
4365                         goto failed_mount;
4366                 }
4367                 if (ext4_has_feature_encrypt(sb)) {
4368                         ext4_msg(sb, KERN_WARNING,
4369                                  "encrypted files will use data=ordered "
4370                                  "instead of data journaling mode");
4371                 }
4372                 if (test_opt(sb, DELALLOC))
4373                         clear_opt(sb, DELALLOC);
4374         } else {
4375                 sb->s_iflags |= SB_I_CGROUPWB;
4376         }
4377
4378         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4379                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4380
4381         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4382             (ext4_has_compat_features(sb) ||
4383              ext4_has_ro_compat_features(sb) ||
4384              ext4_has_incompat_features(sb)))
4385                 ext4_msg(sb, KERN_WARNING,
4386                        "feature flags set on rev 0 fs, "
4387                        "running e2fsck is recommended");
4388
4389         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4390                 set_opt2(sb, HURD_COMPAT);
4391                 if (ext4_has_feature_64bit(sb)) {
4392                         ext4_msg(sb, KERN_ERR,
4393                                  "The Hurd can't support 64-bit file systems");
4394                         goto failed_mount;
4395                 }
4396
4397                 /*
4398                  * ea_inode feature uses l_i_version field which is not
4399                  * available in HURD_COMPAT mode.
4400                  */
4401                 if (ext4_has_feature_ea_inode(sb)) {
4402                         ext4_msg(sb, KERN_ERR,
4403                                  "ea_inode feature is not supported for Hurd");
4404                         goto failed_mount;
4405                 }
4406         }
4407
4408         if (IS_EXT2_SB(sb)) {
4409                 if (ext2_feature_set_ok(sb))
4410                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4411                                  "using the ext4 subsystem");
4412                 else {
4413                         /*
4414                          * If we're probing be silent, if this looks like
4415                          * it's actually an ext[34] filesystem.
4416                          */
4417                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4418                                 goto failed_mount;
4419                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4420                                  "to feature incompatibilities");
4421                         goto failed_mount;
4422                 }
4423         }
4424
4425         if (IS_EXT3_SB(sb)) {
4426                 if (ext3_feature_set_ok(sb))
4427                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4428                                  "using the ext4 subsystem");
4429                 else {
4430                         /*
4431                          * If we're probing be silent, if this looks like
4432                          * it's actually an ext4 filesystem.
4433                          */
4434                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4435                                 goto failed_mount;
4436                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4437                                  "to feature incompatibilities");
4438                         goto failed_mount;
4439                 }
4440         }
4441
4442         /*
4443          * Check feature flags regardless of the revision level, since we
4444          * previously didn't change the revision level when setting the flags,
4445          * so there is a chance incompat flags are set on a rev 0 filesystem.
4446          */
4447         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4448                 goto failed_mount;
4449
4450         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4451                 ext4_msg(sb, KERN_ERR,
4452                          "Number of reserved GDT blocks insanely large: %d",
4453                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4454                 goto failed_mount;
4455         }
4456
4457         if (bdev_dax_supported(sb->s_bdev, blocksize))
4458                 set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4459
4460         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4461                 if (ext4_has_feature_inline_data(sb)) {
4462                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4463                                         " that may contain inline data");
4464                         goto failed_mount;
4465                 }
4466                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4467                         ext4_msg(sb, KERN_ERR,
4468                                 "DAX unsupported by block device.");
4469                         goto failed_mount;
4470                 }
4471         }
4472
4473         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4474                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4475                          es->s_encryption_level);
4476                 goto failed_mount;
4477         }
4478
4479         if (sb->s_blocksize != blocksize) {
4480                 /*
4481                  * bh must be released before kill_bdev(), otherwise
4482                  * it won't be freed and its page also. kill_bdev()
4483                  * is called by sb_set_blocksize().
4484                  */
4485                 brelse(bh);
4486                 /* Validate the filesystem blocksize */
4487                 if (!sb_set_blocksize(sb, blocksize)) {
4488                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4489                                         blocksize);
4490                         bh = NULL;
4491                         goto failed_mount;
4492                 }
4493
4494                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4495                 offset = do_div(logical_sb_block, blocksize);
4496                 bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4497                 if (IS_ERR(bh)) {
4498                         ext4_msg(sb, KERN_ERR,
4499                                "Can't read superblock on 2nd try");
4500                         ret = PTR_ERR(bh);
4501                         bh = NULL;
4502                         goto failed_mount;
4503                 }
4504                 es = (struct ext4_super_block *)(bh->b_data + offset);
4505                 sbi->s_es = es;
4506                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4507                         ext4_msg(sb, KERN_ERR,
4508                                "Magic mismatch, very weird!");
4509                         goto failed_mount;
4510                 }
4511         }
4512
4513         has_huge_files = ext4_has_feature_huge_file(sb);
4514         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4515                                                       has_huge_files);
4516         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4517
4518         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4519         if (ext4_has_feature_64bit(sb)) {
4520                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4521                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4522                     !is_power_of_2(sbi->s_desc_size)) {
4523                         ext4_msg(sb, KERN_ERR,
4524                                "unsupported descriptor size %lu",
4525                                sbi->s_desc_size);
4526                         goto failed_mount;
4527                 }
4528         } else
4529                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4530
4531         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4532         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4533
4534         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4535         if (sbi->s_inodes_per_block == 0)
4536                 goto cantfind_ext4;
4537         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4538             sbi->s_inodes_per_group > blocksize * 8) {
4539                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4540                          sbi->s_inodes_per_group);
4541                 goto failed_mount;
4542         }
4543         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4544                                         sbi->s_inodes_per_block;
4545         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4546         sbi->s_sbh = bh;
4547         sbi->s_mount_state = le16_to_cpu(es->s_state);
4548         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4549         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4550
4551         for (i = 0; i < 4; i++)
4552                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4553         sbi->s_def_hash_version = es->s_def_hash_version;
4554         if (ext4_has_feature_dir_index(sb)) {
4555                 i = le32_to_cpu(es->s_flags);
4556                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4557                         sbi->s_hash_unsigned = 3;
4558                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4559 #ifdef __CHAR_UNSIGNED__
4560                         if (!sb_rdonly(sb))
4561                                 es->s_flags |=
4562                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4563                         sbi->s_hash_unsigned = 3;
4564 #else
4565                         if (!sb_rdonly(sb))
4566                                 es->s_flags |=
4567                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4568 #endif
4569                 }
4570         }
4571
4572         /* Handle clustersize */
4573         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4574         if (ext4_has_feature_bigalloc(sb)) {
4575                 if (clustersize < blocksize) {
4576                         ext4_msg(sb, KERN_ERR,
4577                                  "cluster size (%d) smaller than "
4578                                  "block size (%d)", clustersize, blocksize);
4579                         goto failed_mount;
4580                 }
4581                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4582                         le32_to_cpu(es->s_log_block_size);
4583                 sbi->s_clusters_per_group =
4584                         le32_to_cpu(es->s_clusters_per_group);
4585                 if (sbi->s_clusters_per_group > blocksize * 8) {
4586                         ext4_msg(sb, KERN_ERR,
4587                                  "#clusters per group too big: %lu",
4588                                  sbi->s_clusters_per_group);
4589                         goto failed_mount;
4590                 }
4591                 if (sbi->s_blocks_per_group !=
4592                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4593                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4594                                  "clusters per group (%lu) inconsistent",
4595                                  sbi->s_blocks_per_group,
4596                                  sbi->s_clusters_per_group);
4597                         goto failed_mount;
4598                 }
4599         } else {
4600                 if (clustersize != blocksize) {
4601                         ext4_msg(sb, KERN_ERR,
4602                                  "fragment/cluster size (%d) != "
4603                                  "block size (%d)", clustersize, blocksize);
4604                         goto failed_mount;
4605                 }
4606                 if (sbi->s_blocks_per_group > blocksize * 8) {
4607                         ext4_msg(sb, KERN_ERR,
4608                                  "#blocks per group too big: %lu",
4609                                  sbi->s_blocks_per_group);
4610                         goto failed_mount;
4611                 }
4612                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4613                 sbi->s_cluster_bits = 0;
4614         }
4615         sbi->s_cluster_ratio = clustersize / blocksize;
4616
4617         /* Do we have standard group size of clustersize * 8 blocks ? */
4618         if (sbi->s_blocks_per_group == clustersize << 3)
4619                 set_opt2(sb, STD_GROUP_SIZE);
4620
4621         /*
4622          * Test whether we have more sectors than will fit in sector_t,
4623          * and whether the max offset is addressable by the page cache.
4624          */
4625         err = generic_check_addressable(sb->s_blocksize_bits,
4626                                         ext4_blocks_count(es));
4627         if (err) {
4628                 ext4_msg(sb, KERN_ERR, "filesystem"
4629                          " too large to mount safely on this system");
4630                 goto failed_mount;
4631         }
4632
4633         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4634                 goto cantfind_ext4;
4635
4636         /* check blocks count against device size */
4637         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4638         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4639                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4640                        "exceeds size of device (%llu blocks)",
4641                        ext4_blocks_count(es), blocks_count);
4642                 goto failed_mount;
4643         }
4644
4645         /*
4646          * It makes no sense for the first data block to be beyond the end
4647          * of the filesystem.
4648          */
4649         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4650                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4651                          "block %u is beyond end of filesystem (%llu)",
4652                          le32_to_cpu(es->s_first_data_block),
4653                          ext4_blocks_count(es));
4654                 goto failed_mount;
4655         }
4656         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4657             (sbi->s_cluster_ratio == 1)) {
4658                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4659                          "block is 0 with a 1k block and cluster size");
4660                 goto failed_mount;
4661         }
4662
4663         blocks_count = (ext4_blocks_count(es) -
4664                         le32_to_cpu(es->s_first_data_block) +
4665                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4666         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4667         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4668                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4669                        "(block count %llu, first data block %u, "
4670                        "blocks per group %lu)", blocks_count,
4671                        ext4_blocks_count(es),
4672                        le32_to_cpu(es->s_first_data_block),
4673                        EXT4_BLOCKS_PER_GROUP(sb));
4674                 goto failed_mount;
4675         }
4676         sbi->s_groups_count = blocks_count;
4677         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4678                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4679         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4680             le32_to_cpu(es->s_inodes_count)) {
4681                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4682                          le32_to_cpu(es->s_inodes_count),
4683                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4684                 ret = -EINVAL;
4685                 goto failed_mount;
4686         }
4687         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4688                    EXT4_DESC_PER_BLOCK(sb);
4689         if (ext4_has_feature_meta_bg(sb)) {
4690                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4691                         ext4_msg(sb, KERN_WARNING,
4692                                  "first meta block group too large: %u "
4693                                  "(group descriptor block count %u)",
4694                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4695                         goto failed_mount;
4696                 }
4697         }
4698         rcu_assign_pointer(sbi->s_group_desc,
4699                            kvmalloc_array(db_count,
4700                                           sizeof(struct buffer_head *),
4701                                           GFP_KERNEL));
4702         if (sbi->s_group_desc == NULL) {
4703                 ext4_msg(sb, KERN_ERR, "not enough memory");
4704                 ret = -ENOMEM;
4705                 goto failed_mount;
4706         }
4707
4708         bgl_lock_init(sbi->s_blockgroup_lock);
4709
4710         /* Pre-read the descriptors into the buffer cache */
4711         for (i = 0; i < db_count; i++) {
4712                 block = descriptor_loc(sb, logical_sb_block, i);
4713                 ext4_sb_breadahead_unmovable(sb, block);
4714         }
4715
4716         for (i = 0; i < db_count; i++) {
4717                 struct buffer_head *bh;
4718
4719                 block = descriptor_loc(sb, logical_sb_block, i);
4720                 bh = ext4_sb_bread_unmovable(sb, block);
4721                 if (IS_ERR(bh)) {
4722                         ext4_msg(sb, KERN_ERR,
4723                                "can't read group descriptor %d", i);
4724                         db_count = i;
4725                         ret = PTR_ERR(bh);
4726                         goto failed_mount2;
4727                 }
4728                 rcu_read_lock();
4729                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4730                 rcu_read_unlock();
4731         }
4732         sbi->s_gdb_count = db_count;
4733         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4734                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4735                 ret = -EFSCORRUPTED;
4736                 goto failed_mount2;
4737         }
4738
4739         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4740         spin_lock_init(&sbi->s_error_lock);
4741         INIT_WORK(&sbi->s_error_work, flush_stashed_error_work);
4742
4743         /* Register extent status tree shrinker */
4744         if (ext4_es_register_shrinker(sbi))
4745                 goto failed_mount3;
4746
4747         sbi->s_stripe = ext4_get_stripe_size(sbi);
4748         sbi->s_extent_max_zeroout_kb = 32;
4749
4750         /*
4751          * set up enough so that it can read an inode
4752          */
4753         sb->s_op = &ext4_sops;
4754         sb->s_export_op = &ext4_export_ops;
4755         sb->s_xattr = ext4_xattr_handlers;
4756 #ifdef CONFIG_FS_ENCRYPTION
4757         sb->s_cop = &ext4_cryptops;
4758 #endif
4759 #ifdef CONFIG_FS_VERITY
4760         sb->s_vop = &ext4_verityops;
4761 #endif
4762 #ifdef CONFIG_QUOTA
4763         sb->dq_op = &ext4_quota_operations;
4764         if (ext4_has_feature_quota(sb))
4765                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4766         else
4767                 sb->s_qcop = &ext4_qctl_operations;
4768         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4769 #endif
4770         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4771
4772         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4773         mutex_init(&sbi->s_orphan_lock);
4774
4775         /* Initialize fast commit stuff */
4776         atomic_set(&sbi->s_fc_subtid, 0);
4777         atomic_set(&sbi->s_fc_ineligible_updates, 0);
4778         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4779         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4780         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4781         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4782         sbi->s_fc_bytes = 0;
4783         ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
4784         ext4_clear_mount_flag(sb, EXT4_MF_FC_COMMITTING);
4785         spin_lock_init(&sbi->s_fc_lock);
4786         memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4787         sbi->s_fc_replay_state.fc_regions = NULL;
4788         sbi->s_fc_replay_state.fc_regions_size = 0;
4789         sbi->s_fc_replay_state.fc_regions_used = 0;
4790         sbi->s_fc_replay_state.fc_regions_valid = 0;
4791         sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4792         sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4793         sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4794
4795         sb->s_root = NULL;
4796
4797         needs_recovery = (es->s_last_orphan != 0 ||
4798                           ext4_has_feature_journal_needs_recovery(sb));
4799
4800         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4801                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4802                         goto failed_mount3a;
4803
4804         /*
4805          * The first inode we look at is the journal inode.  Don't try
4806          * root first: it may be modified in the journal!
4807          */
4808         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4809                 err = ext4_load_journal(sb, es, parsed_opts.journal_devnum);
4810                 if (err)
4811                         goto failed_mount3a;
4812         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4813                    ext4_has_feature_journal_needs_recovery(sb)) {
4814                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4815                        "suppressed and not mounted read-only");
4816                 goto failed_mount_wq;
4817         } else {
4818                 /* Nojournal mode, all journal mount options are illegal */
4819                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4820                         ext4_msg(sb, KERN_ERR, "can't mount with "
4821                                  "journal_checksum, fs mounted w/o journal");
4822                         goto failed_mount_wq;
4823                 }
4824                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4825                         ext4_msg(sb, KERN_ERR, "can't mount with "
4826                                  "journal_async_commit, fs mounted w/o journal");
4827                         goto failed_mount_wq;
4828                 }
4829                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4830                         ext4_msg(sb, KERN_ERR, "can't mount with "
4831                                  "commit=%lu, fs mounted w/o journal",
4832                                  sbi->s_commit_interval / HZ);
4833                         goto failed_mount_wq;
4834                 }
4835                 if (EXT4_MOUNT_DATA_FLAGS &
4836                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4837                         ext4_msg(sb, KERN_ERR, "can't mount with "
4838                                  "data=, fs mounted w/o journal");
4839                         goto failed_mount_wq;
4840                 }
4841                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4842                 clear_opt(sb, JOURNAL_CHECKSUM);
4843                 clear_opt(sb, DATA_FLAGS);
4844                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4845                 sbi->s_journal = NULL;
4846                 needs_recovery = 0;
4847                 goto no_journal;
4848         }
4849
4850         if (ext4_has_feature_64bit(sb) &&
4851             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4852                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4853                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4854                 goto failed_mount_wq;
4855         }
4856
4857         if (!set_journal_csum_feature_set(sb)) {
4858                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4859                          "feature set");
4860                 goto failed_mount_wq;
4861         }
4862
4863         if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4864                 !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4865                                           JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
4866                 ext4_msg(sb, KERN_ERR,
4867                         "Failed to set fast commit journal feature");
4868                 goto failed_mount_wq;
4869         }
4870
4871         /* We have now updated the journal if required, so we can
4872          * validate the data journaling mode. */
4873         switch (test_opt(sb, DATA_FLAGS)) {
4874         case 0:
4875                 /* No mode set, assume a default based on the journal
4876                  * capabilities: ORDERED_DATA if the journal can
4877                  * cope, else JOURNAL_DATA
4878                  */
4879                 if (jbd2_journal_check_available_features
4880                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4881                         set_opt(sb, ORDERED_DATA);
4882                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4883                 } else {
4884                         set_opt(sb, JOURNAL_DATA);
4885                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4886                 }
4887                 break;
4888
4889         case EXT4_MOUNT_ORDERED_DATA:
4890         case EXT4_MOUNT_WRITEBACK_DATA:
4891                 if (!jbd2_journal_check_available_features
4892                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4893                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4894                                "requested data journaling mode");
4895                         goto failed_mount_wq;
4896                 }
4897                 break;
4898         default:
4899                 break;
4900         }
4901
4902         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4903             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4904                 ext4_msg(sb, KERN_ERR, "can't mount with "
4905                         "journal_async_commit in data=ordered mode");
4906                 goto failed_mount_wq;
4907         }
4908
4909         set_task_ioprio(sbi->s_journal->j_task, parsed_opts.journal_ioprio);
4910
4911         sbi->s_journal->j_submit_inode_data_buffers =
4912                 ext4_journal_submit_inode_data_buffers;
4913         sbi->s_journal->j_finish_inode_data_buffers =
4914                 ext4_journal_finish_inode_data_buffers;
4915
4916 no_journal:
4917         if (!test_opt(sb, NO_MBCACHE)) {
4918                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4919                 if (!sbi->s_ea_block_cache) {
4920                         ext4_msg(sb, KERN_ERR,
4921                                  "Failed to create ea_block_cache");
4922                         goto failed_mount_wq;
4923                 }
4924
4925                 if (ext4_has_feature_ea_inode(sb)) {
4926                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4927                         if (!sbi->s_ea_inode_cache) {
4928                                 ext4_msg(sb, KERN_ERR,
4929                                          "Failed to create ea_inode_cache");
4930                                 goto failed_mount_wq;
4931                         }
4932                 }
4933         }
4934
4935         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4936                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4937                 goto failed_mount_wq;
4938         }
4939
4940         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4941             !ext4_has_feature_encrypt(sb)) {
4942                 ext4_set_feature_encrypt(sb);
4943                 ext4_commit_super(sb);
4944         }
4945
4946         /*
4947          * Get the # of file system overhead blocks from the
4948          * superblock if present.
4949          */
4950         if (es->s_overhead_clusters)
4951                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4952         else {
4953                 err = ext4_calculate_overhead(sb);
4954                 if (err)
4955                         goto failed_mount_wq;
4956         }
4957
4958         /*
4959          * The maximum number of concurrent works can be high and
4960          * concurrency isn't really necessary.  Limit it to 1.
4961          */
4962         EXT4_SB(sb)->rsv_conversion_wq =
4963                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4964         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4965                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4966                 ret = -ENOMEM;
4967                 goto failed_mount4;
4968         }
4969
4970         /*
4971          * The jbd2_journal_load will have done any necessary log recovery,
4972          * so we can safely mount the rest of the filesystem now.
4973          */
4974
4975         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4976         if (IS_ERR(root)) {
4977                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4978                 ret = PTR_ERR(root);
4979                 root = NULL;
4980                 goto failed_mount4;
4981         }
4982         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4983                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4984                 iput(root);
4985                 goto failed_mount4;
4986         }
4987
4988         sb->s_root = d_make_root(root);
4989         if (!sb->s_root) {
4990                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4991                 ret = -ENOMEM;
4992                 goto failed_mount4;
4993         }
4994
4995         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4996         if (ret == -EROFS) {
4997                 sb->s_flags |= SB_RDONLY;
4998                 ret = 0;
4999         } else if (ret)
5000                 goto failed_mount4a;
5001
5002         ext4_set_resv_clusters(sb);
5003
5004         if (test_opt(sb, BLOCK_VALIDITY)) {
5005                 err = ext4_setup_system_zone(sb);
5006                 if (err) {
5007                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
5008                                  "zone (%d)", err);
5009                         goto failed_mount4a;
5010                 }
5011         }
5012         ext4_fc_replay_cleanup(sb);
5013
5014         ext4_ext_init(sb);
5015
5016         /*
5017          * Enable optimize_scan if number of groups is > threshold. This can be
5018          * turned off by passing "mb_optimize_scan=0". This can also be
5019          * turned on forcefully by passing "mb_optimize_scan=1".
5020          */
5021         if (parsed_opts.mb_optimize_scan == 1)
5022                 set_opt2(sb, MB_OPTIMIZE_SCAN);
5023         else if (parsed_opts.mb_optimize_scan == 0)
5024                 clear_opt2(sb, MB_OPTIMIZE_SCAN);
5025         else if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
5026                 set_opt2(sb, MB_OPTIMIZE_SCAN);
5027
5028         err = ext4_mb_init(sb);
5029         if (err) {
5030                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5031                          err);
5032                 goto failed_mount5;
5033         }
5034
5035         /*
5036          * We can only set up the journal commit callback once
5037          * mballoc is initialized
5038          */
5039         if (sbi->s_journal)
5040                 sbi->s_journal->j_commit_callback =
5041                         ext4_journal_commit_callback;
5042
5043         block = ext4_count_free_clusters(sb);
5044         ext4_free_blocks_count_set(sbi->s_es,
5045                                    EXT4_C2B(sbi, block));
5046         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
5047                                   GFP_KERNEL);
5048         if (!err) {
5049                 unsigned long freei = ext4_count_free_inodes(sb);
5050                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
5051                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
5052                                           GFP_KERNEL);
5053         }
5054         if (!err)
5055                 err = percpu_counter_init(&sbi->s_dirs_counter,
5056                                           ext4_count_dirs(sb), GFP_KERNEL);
5057         if (!err)
5058                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
5059                                           GFP_KERNEL);
5060         if (!err)
5061                 err = percpu_counter_init(&sbi->s_sra_exceeded_retry_limit, 0,
5062                                           GFP_KERNEL);
5063         if (!err)
5064                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
5065
5066         if (err) {
5067                 ext4_msg(sb, KERN_ERR, "insufficient memory");
5068                 goto failed_mount6;
5069         }
5070
5071         if (ext4_has_feature_flex_bg(sb))
5072                 if (!ext4_fill_flex_info(sb)) {
5073                         ext4_msg(sb, KERN_ERR,
5074                                "unable to initialize "
5075                                "flex_bg meta info!");
5076                         ret = -ENOMEM;
5077                         goto failed_mount6;
5078                 }
5079
5080         err = ext4_register_li_request(sb, first_not_zeroed);
5081         if (err)
5082                 goto failed_mount6;
5083
5084         err = ext4_register_sysfs(sb);
5085         if (err)
5086                 goto failed_mount7;
5087
5088 #ifdef CONFIG_QUOTA
5089         /* Enable quota usage during mount. */
5090         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5091                 err = ext4_enable_quotas(sb);
5092                 if (err)
5093                         goto failed_mount8;
5094         }
5095 #endif  /* CONFIG_QUOTA */
5096
5097         /*
5098          * Save the original bdev mapping's wb_err value which could be
5099          * used to detect the metadata async write error.
5100          */
5101         spin_lock_init(&sbi->s_bdev_wb_lock);
5102         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5103                                  &sbi->s_bdev_wb_err);
5104         sb->s_bdev->bd_super = sb;
5105         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5106         ext4_orphan_cleanup(sb, es);
5107         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5108         if (needs_recovery) {
5109                 ext4_msg(sb, KERN_INFO, "recovery complete");
5110                 err = ext4_mark_recovery_complete(sb, es);
5111                 if (err)
5112                         goto failed_mount8;
5113         }
5114         if (EXT4_SB(sb)->s_journal) {
5115                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5116                         descr = " journalled data mode";
5117                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5118                         descr = " ordered data mode";
5119                 else
5120                         descr = " writeback data mode";
5121         } else
5122                 descr = "out journal";
5123
5124         if (test_opt(sb, DISCARD)) {
5125                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
5126                 if (!blk_queue_discard(q))
5127                         ext4_msg(sb, KERN_WARNING,
5128                                  "mounting with \"discard\" option, but "
5129                                  "the device does not support discard");
5130         }
5131
5132         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5133                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
5134                          "Opts: %.*s%s%s. Quota mode: %s.", descr,
5135                          (int) sizeof(sbi->s_es->s_mount_opts),
5136                          sbi->s_es->s_mount_opts,
5137                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data,
5138                          ext4_quota_mode(sb));
5139
5140         if (es->s_error_count)
5141                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5142
5143         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5144         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5145         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5146         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5147         atomic_set(&sbi->s_warning_count, 0);
5148         atomic_set(&sbi->s_msg_count, 0);
5149
5150         kfree(orig_data);
5151         return 0;
5152
5153 cantfind_ext4:
5154         if (!silent)
5155                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5156         goto failed_mount;
5157
5158 failed_mount8:
5159         ext4_unregister_sysfs(sb);
5160         kobject_put(&sbi->s_kobj);
5161 failed_mount7:
5162         ext4_unregister_li_request(sb);
5163 failed_mount6:
5164         ext4_mb_release(sb);
5165         rcu_read_lock();
5166         flex_groups = rcu_dereference(sbi->s_flex_groups);
5167         if (flex_groups) {
5168                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
5169                         kvfree(flex_groups[i]);
5170                 kvfree(flex_groups);
5171         }
5172         rcu_read_unlock();
5173         percpu_counter_destroy(&sbi->s_freeclusters_counter);
5174         percpu_counter_destroy(&sbi->s_freeinodes_counter);
5175         percpu_counter_destroy(&sbi->s_dirs_counter);
5176         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
5177         percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
5178         percpu_free_rwsem(&sbi->s_writepages_rwsem);
5179 failed_mount5:
5180         ext4_ext_release(sb);
5181         ext4_release_system_zone(sb);
5182 failed_mount4a:
5183         dput(sb->s_root);
5184         sb->s_root = NULL;
5185 failed_mount4:
5186         ext4_msg(sb, KERN_ERR, "mount failed");
5187         if (EXT4_SB(sb)->rsv_conversion_wq)
5188                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5189 failed_mount_wq:
5190         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5191         sbi->s_ea_inode_cache = NULL;
5192
5193         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5194         sbi->s_ea_block_cache = NULL;
5195
5196         if (sbi->s_journal) {
5197                 jbd2_journal_destroy(sbi->s_journal);
5198                 sbi->s_journal = NULL;
5199         }
5200 failed_mount3a:
5201         ext4_es_unregister_shrinker(sbi);
5202 failed_mount3:
5203         flush_work(&sbi->s_error_work);
5204         del_timer_sync(&sbi->s_err_report);
5205         ext4_stop_mmpd(sbi);
5206 failed_mount2:
5207         rcu_read_lock();
5208         group_desc = rcu_dereference(sbi->s_group_desc);
5209         for (i = 0; i < db_count; i++)
5210                 brelse(group_desc[i]);
5211         kvfree(group_desc);
5212         rcu_read_unlock();
5213 failed_mount:
5214         if (sbi->s_chksum_driver)
5215                 crypto_free_shash(sbi->s_chksum_driver);
5216
5217 #ifdef CONFIG_UNICODE
5218         utf8_unload(sb->s_encoding);
5219 #endif
5220
5221 #ifdef CONFIG_QUOTA
5222         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5223                 kfree(get_qf_name(sb, sbi, i));
5224 #endif
5225         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5226         /* ext4_blkdev_remove() calls kill_bdev(), release bh before it. */
5227         brelse(bh);
5228         ext4_blkdev_remove(sbi);
5229 out_fail:
5230         sb->s_fs_info = NULL;
5231         kfree(sbi->s_blockgroup_lock);
5232 out_free_base:
5233         kfree(sbi);
5234         kfree(orig_data);
5235         fs_put_dax(dax_dev);
5236         return err ? err : ret;
5237 }
5238
5239 /*
5240  * Setup any per-fs journal parameters now.  We'll do this both on
5241  * initial mount, once the journal has been initialised but before we've
5242  * done any recovery; and again on any subsequent remount.
5243  */
5244 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5245 {
5246         struct ext4_sb_info *sbi = EXT4_SB(sb);
5247
5248         journal->j_commit_interval = sbi->s_commit_interval;
5249         journal->j_min_batch_time = sbi->s_min_batch_time;
5250         journal->j_max_batch_time = sbi->s_max_batch_time;
5251         ext4_fc_init(sb, journal);
5252
5253         write_lock(&journal->j_state_lock);
5254         if (test_opt(sb, BARRIER))
5255                 journal->j_flags |= JBD2_BARRIER;
5256         else
5257                 journal->j_flags &= ~JBD2_BARRIER;
5258         if (test_opt(sb, DATA_ERR_ABORT))
5259                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5260         else
5261                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5262         write_unlock(&journal->j_state_lock);
5263 }
5264
5265 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5266                                              unsigned int journal_inum)
5267 {
5268         struct inode *journal_inode;
5269
5270         /*
5271          * Test for the existence of a valid inode on disk.  Bad things
5272          * happen if we iget() an unused inode, as the subsequent iput()
5273          * will try to delete it.
5274          */
5275         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5276         if (IS_ERR(journal_inode)) {
5277                 ext4_msg(sb, KERN_ERR, "no journal found");
5278                 return NULL;
5279         }
5280         if (!journal_inode->i_nlink) {
5281                 make_bad_inode(journal_inode);
5282                 iput(journal_inode);
5283                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5284                 return NULL;
5285         }
5286
5287         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
5288                   journal_inode, journal_inode->i_size);
5289         if (!S_ISREG(journal_inode->i_mode)) {
5290                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5291                 iput(journal_inode);
5292                 return NULL;
5293         }
5294         return journal_inode;
5295 }
5296
5297 static journal_t *ext4_get_journal(struct super_block *sb,
5298                                    unsigned int journal_inum)
5299 {
5300         struct inode *journal_inode;
5301         journal_t *journal;
5302
5303         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5304                 return NULL;
5305
5306         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5307         if (!journal_inode)
5308                 return NULL;
5309
5310         journal = jbd2_journal_init_inode(journal_inode);
5311         if (!journal) {
5312                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5313                 iput(journal_inode);
5314                 return NULL;
5315         }
5316         journal->j_private = sb;
5317         ext4_init_journal_params(sb, journal);
5318         return journal;
5319 }
5320
5321 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5322                                        dev_t j_dev)
5323 {
5324         struct buffer_head *bh;
5325         journal_t *journal;
5326         ext4_fsblk_t start;
5327         ext4_fsblk_t len;
5328         int hblock, blocksize;
5329         ext4_fsblk_t sb_block;
5330         unsigned long offset;
5331         struct ext4_super_block *es;
5332         struct block_device *bdev;
5333
5334         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5335                 return NULL;
5336
5337         bdev = ext4_blkdev_get(j_dev, sb);
5338         if (bdev == NULL)
5339                 return NULL;
5340
5341         blocksize = sb->s_blocksize;
5342         hblock = bdev_logical_block_size(bdev);
5343         if (blocksize < hblock) {
5344                 ext4_msg(sb, KERN_ERR,
5345                         "blocksize too small for journal device");
5346                 goto out_bdev;
5347         }
5348
5349         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5350         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5351         set_blocksize(bdev, blocksize);
5352         if (!(bh = __bread(bdev, sb_block, blocksize))) {
5353                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5354                        "external journal");
5355                 goto out_bdev;
5356         }
5357
5358         es = (struct ext4_super_block *) (bh->b_data + offset);
5359         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5360             !(le32_to_cpu(es->s_feature_incompat) &
5361               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5362                 ext4_msg(sb, KERN_ERR, "external journal has "
5363                                         "bad superblock");
5364                 brelse(bh);
5365                 goto out_bdev;
5366         }
5367
5368         if ((le32_to_cpu(es->s_feature_ro_compat) &
5369              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5370             es->s_checksum != ext4_superblock_csum(sb, es)) {
5371                 ext4_msg(sb, KERN_ERR, "external journal has "
5372                                        "corrupt superblock");
5373                 brelse(bh);
5374                 goto out_bdev;
5375         }
5376
5377         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5378                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5379                 brelse(bh);
5380                 goto out_bdev;
5381         }
5382
5383         len = ext4_blocks_count(es);
5384         start = sb_block + 1;
5385         brelse(bh);     /* we're done with the superblock */
5386
5387         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5388                                         start, len, blocksize);
5389         if (!journal) {
5390                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5391                 goto out_bdev;
5392         }
5393         journal->j_private = sb;
5394         if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
5395                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5396                 goto out_journal;
5397         }
5398         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5399                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5400                                         "user (unsupported) - %d",
5401                         be32_to_cpu(journal->j_superblock->s_nr_users));
5402                 goto out_journal;
5403         }
5404         EXT4_SB(sb)->s_journal_bdev = bdev;
5405         ext4_init_journal_params(sb, journal);
5406         return journal;
5407
5408 out_journal:
5409         jbd2_journal_destroy(journal);
5410 out_bdev:
5411         ext4_blkdev_put(bdev);
5412         return NULL;
5413 }
5414
5415 static int ext4_load_journal(struct super_block *sb,
5416                              struct ext4_super_block *es,
5417                              unsigned long journal_devnum)
5418 {
5419         journal_t *journal;
5420         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5421         dev_t journal_dev;
5422         int err = 0;
5423         int really_read_only;
5424         int journal_dev_ro;
5425
5426         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5427                 return -EFSCORRUPTED;
5428
5429         if (journal_devnum &&
5430             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5431                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5432                         "numbers have changed");
5433                 journal_dev = new_decode_dev(journal_devnum);
5434         } else
5435                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5436
5437         if (journal_inum && journal_dev) {
5438                 ext4_msg(sb, KERN_ERR,
5439                          "filesystem has both journal inode and journal device!");
5440                 return -EINVAL;
5441         }
5442
5443         if (journal_inum) {
5444                 journal = ext4_get_journal(sb, journal_inum);
5445                 if (!journal)
5446                         return -EINVAL;
5447         } else {
5448                 journal = ext4_get_dev_journal(sb, journal_dev);
5449                 if (!journal)
5450                         return -EINVAL;
5451         }
5452
5453         journal_dev_ro = bdev_read_only(journal->j_dev);
5454         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5455
5456         if (journal_dev_ro && !sb_rdonly(sb)) {
5457                 ext4_msg(sb, KERN_ERR,
5458                          "journal device read-only, try mounting with '-o ro'");
5459                 err = -EROFS;
5460                 goto err_out;
5461         }
5462
5463         /*
5464          * Are we loading a blank journal or performing recovery after a
5465          * crash?  For recovery, we need to check in advance whether we
5466          * can get read-write access to the device.
5467          */
5468         if (ext4_has_feature_journal_needs_recovery(sb)) {
5469                 if (sb_rdonly(sb)) {
5470                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5471                                         "required on readonly filesystem");
5472                         if (really_read_only) {
5473                                 ext4_msg(sb, KERN_ERR, "write access "
5474                                         "unavailable, cannot proceed "
5475                                         "(try mounting with noload)");
5476                                 err = -EROFS;
5477                                 goto err_out;
5478                         }
5479                         ext4_msg(sb, KERN_INFO, "write access will "
5480                                "be enabled during recovery");
5481                 }
5482         }
5483
5484         if (!(journal->j_flags & JBD2_BARRIER))
5485                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5486
5487         if (!ext4_has_feature_journal_needs_recovery(sb))
5488                 err = jbd2_journal_wipe(journal, !really_read_only);
5489         if (!err) {
5490                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5491                 if (save)
5492                         memcpy(save, ((char *) es) +
5493                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5494                 err = jbd2_journal_load(journal);
5495                 if (save)
5496                         memcpy(((char *) es) + EXT4_S_ERR_START,
5497                                save, EXT4_S_ERR_LEN);
5498                 kfree(save);
5499         }
5500
5501         if (err) {
5502                 ext4_msg(sb, KERN_ERR, "error loading journal");
5503                 goto err_out;
5504         }
5505
5506         EXT4_SB(sb)->s_journal = journal;
5507         err = ext4_clear_journal_err(sb, es);
5508         if (err) {
5509                 EXT4_SB(sb)->s_journal = NULL;
5510                 jbd2_journal_destroy(journal);
5511                 return err;
5512         }
5513
5514         if (!really_read_only && journal_devnum &&
5515             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5516                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5517
5518                 /* Make sure we flush the recovery flag to disk. */
5519                 ext4_commit_super(sb);
5520         }
5521
5522         return 0;
5523
5524 err_out:
5525         jbd2_journal_destroy(journal);
5526         return err;
5527 }
5528
5529 /* Copy state of EXT4_SB(sb) into buffer for on-disk superblock */
5530 static void ext4_update_super(struct super_block *sb)
5531 {
5532         struct ext4_sb_info *sbi = EXT4_SB(sb);
5533         struct ext4_super_block *es = sbi->s_es;
5534         struct buffer_head *sbh = sbi->s_sbh;
5535
5536         lock_buffer(sbh);
5537         /*
5538          * If the file system is mounted read-only, don't update the
5539          * superblock write time.  This avoids updating the superblock
5540          * write time when we are mounting the root file system
5541          * read/only but we need to replay the journal; at that point,
5542          * for people who are east of GMT and who make their clock
5543          * tick in localtime for Windows bug-for-bug compatibility,
5544          * the clock is set in the future, and this will cause e2fsck
5545          * to complain and force a full file system check.
5546          */
5547         if (!(sb->s_flags & SB_RDONLY))
5548                 ext4_update_tstamp(es, s_wtime);
5549         es->s_kbytes_written =
5550                 cpu_to_le64(sbi->s_kbytes_written +
5551                     ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
5552                       sbi->s_sectors_written_start) >> 1));
5553         if (percpu_counter_initialized(&sbi->s_freeclusters_counter))
5554                 ext4_free_blocks_count_set(es,
5555                         EXT4_C2B(sbi, percpu_counter_sum_positive(
5556                                 &sbi->s_freeclusters_counter)));
5557         if (percpu_counter_initialized(&sbi->s_freeinodes_counter))
5558                 es->s_free_inodes_count =
5559                         cpu_to_le32(percpu_counter_sum_positive(
5560                                 &sbi->s_freeinodes_counter));
5561         /* Copy error information to the on-disk superblock */
5562         spin_lock(&sbi->s_error_lock);
5563         if (sbi->s_add_error_count > 0) {
5564                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5565                 if (!es->s_first_error_time && !es->s_first_error_time_hi) {
5566                         __ext4_update_tstamp(&es->s_first_error_time,
5567                                              &es->s_first_error_time_hi,
5568                                              sbi->s_first_error_time);
5569                         strncpy(es->s_first_error_func, sbi->s_first_error_func,
5570                                 sizeof(es->s_first_error_func));
5571                         es->s_first_error_line =
5572                                 cpu_to_le32(sbi->s_first_error_line);
5573                         es->s_first_error_ino =
5574                                 cpu_to_le32(sbi->s_first_error_ino);
5575                         es->s_first_error_block =
5576                                 cpu_to_le64(sbi->s_first_error_block);
5577                         es->s_first_error_errcode =
5578                                 ext4_errno_to_code(sbi->s_first_error_code);
5579                 }
5580                 __ext4_update_tstamp(&es->s_last_error_time,
5581                                      &es->s_last_error_time_hi,
5582                                      sbi->s_last_error_time);
5583                 strncpy(es->s_last_error_func, sbi->s_last_error_func,
5584                         sizeof(es->s_last_error_func));
5585                 es->s_last_error_line = cpu_to_le32(sbi->s_last_error_line);
5586                 es->s_last_error_ino = cpu_to_le32(sbi->s_last_error_ino);
5587                 es->s_last_error_block = cpu_to_le64(sbi->s_last_error_block);
5588                 es->s_last_error_errcode =
5589                                 ext4_errno_to_code(sbi->s_last_error_code);
5590                 /*
5591                  * Start the daily error reporting function if it hasn't been
5592                  * started already
5593                  */
5594                 if (!es->s_error_count)
5595                         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
5596                 le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
5597                 sbi->s_add_error_count = 0;
5598         }
5599         spin_unlock(&sbi->s_error_lock);
5600
5601         ext4_superblock_csum_set(sb);
5602         unlock_buffer(sbh);
5603 }
5604
5605 static int ext4_commit_super(struct super_block *sb)
5606 {
5607         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5608         int error = 0;
5609
5610         if (!sbh)
5611                 return -EINVAL;
5612         if (block_device_ejected(sb))
5613                 return -ENODEV;
5614
5615         ext4_update_super(sb);
5616
5617         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5618                 /*
5619                  * Oh, dear.  A previous attempt to write the
5620                  * superblock failed.  This could happen because the
5621                  * USB device was yanked out.  Or it could happen to
5622                  * be a transient write error and maybe the block will
5623                  * be remapped.  Nothing we can do but to retry the
5624                  * write and hope for the best.
5625                  */
5626                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5627                        "superblock detected");
5628                 clear_buffer_write_io_error(sbh);
5629                 set_buffer_uptodate(sbh);
5630         }
5631         BUFFER_TRACE(sbh, "marking dirty");
5632         mark_buffer_dirty(sbh);
5633         error = __sync_dirty_buffer(sbh,
5634                 REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5635         if (buffer_write_io_error(sbh)) {
5636                 ext4_msg(sb, KERN_ERR, "I/O error while writing "
5637                        "superblock");
5638                 clear_buffer_write_io_error(sbh);
5639                 set_buffer_uptodate(sbh);
5640         }
5641         return error;
5642 }
5643
5644 /*
5645  * Have we just finished recovery?  If so, and if we are mounting (or
5646  * remounting) the filesystem readonly, then we will end up with a
5647  * consistent fs on disk.  Record that fact.
5648  */
5649 static int ext4_mark_recovery_complete(struct super_block *sb,
5650                                        struct ext4_super_block *es)
5651 {
5652         int err;
5653         journal_t *journal = EXT4_SB(sb)->s_journal;
5654
5655         if (!ext4_has_feature_journal(sb)) {
5656                 if (journal != NULL) {
5657                         ext4_error(sb, "Journal got removed while the fs was "
5658                                    "mounted!");
5659                         return -EFSCORRUPTED;
5660                 }
5661                 return 0;
5662         }
5663         jbd2_journal_lock_updates(journal);
5664         err = jbd2_journal_flush(journal);
5665         if (err < 0)
5666                 goto out;
5667
5668         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5669                 ext4_clear_feature_journal_needs_recovery(sb);
5670                 ext4_commit_super(sb);
5671         }
5672 out:
5673         jbd2_journal_unlock_updates(journal);
5674         return err;
5675 }
5676
5677 /*
5678  * If we are mounting (or read-write remounting) a filesystem whose journal
5679  * has recorded an error from a previous lifetime, move that error to the
5680  * main filesystem now.
5681  */
5682 static int ext4_clear_journal_err(struct super_block *sb,
5683                                    struct ext4_super_block *es)
5684 {
5685         journal_t *journal;
5686         int j_errno;
5687         const char *errstr;
5688
5689         if (!ext4_has_feature_journal(sb)) {
5690                 ext4_error(sb, "Journal got removed while the fs was mounted!");
5691                 return -EFSCORRUPTED;
5692         }
5693
5694         journal = EXT4_SB(sb)->s_journal;
5695
5696         /*
5697          * Now check for any error status which may have been recorded in the
5698          * journal by a prior ext4_error() or ext4_abort()
5699          */
5700
5701         j_errno = jbd2_journal_errno(journal);
5702         if (j_errno) {
5703                 char nbuf[16];
5704
5705                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5706                 ext4_warning(sb, "Filesystem error recorded "
5707                              "from previous mount: %s", errstr);
5708                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5709
5710                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5711                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5712                 ext4_commit_super(sb);
5713
5714                 jbd2_journal_clear_err(journal);
5715                 jbd2_journal_update_sb_errno(journal);
5716         }
5717         return 0;
5718 }
5719
5720 /*
5721  * Force the running and committing transactions to commit,
5722  * and wait on the commit.
5723  */
5724 int ext4_force_commit(struct super_block *sb)
5725 {
5726         journal_t *journal;
5727
5728         if (sb_rdonly(sb))
5729                 return 0;
5730
5731         journal = EXT4_SB(sb)->s_journal;
5732         return ext4_journal_force_commit(journal);
5733 }
5734
5735 static int ext4_sync_fs(struct super_block *sb, int wait)
5736 {
5737         int ret = 0;
5738         tid_t target;
5739         bool needs_barrier = false;
5740         struct ext4_sb_info *sbi = EXT4_SB(sb);
5741
5742         if (unlikely(ext4_forced_shutdown(sbi)))
5743                 return 0;
5744
5745         trace_ext4_sync_fs(sb, wait);
5746         flush_workqueue(sbi->rsv_conversion_wq);
5747         /*
5748          * Writeback quota in non-journalled quota case - journalled quota has
5749          * no dirty dquots
5750          */
5751         dquot_writeback_dquots(sb, -1);
5752         /*
5753          * Data writeback is possible w/o journal transaction, so barrier must
5754          * being sent at the end of the function. But we can skip it if
5755          * transaction_commit will do it for us.
5756          */
5757         if (sbi->s_journal) {
5758                 target = jbd2_get_latest_transaction(sbi->s_journal);
5759                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5760                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5761                         needs_barrier = true;
5762
5763                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5764                         if (wait)
5765                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5766                                                            target);
5767                 }
5768         } else if (wait && test_opt(sb, BARRIER))
5769                 needs_barrier = true;
5770         if (needs_barrier) {
5771                 int err;
5772                 err = blkdev_issue_flush(sb->s_bdev);
5773                 if (!ret)
5774                         ret = err;
5775         }
5776
5777         return ret;
5778 }
5779
5780 /*
5781  * LVM calls this function before a (read-only) snapshot is created.  This
5782  * gives us a chance to flush the journal completely and mark the fs clean.
5783  *
5784  * Note that only this function cannot bring a filesystem to be in a clean
5785  * state independently. It relies on upper layer to stop all data & metadata
5786  * modifications.
5787  */
5788 static int ext4_freeze(struct super_block *sb)
5789 {
5790         int error = 0;
5791         journal_t *journal;
5792
5793         if (sb_rdonly(sb))
5794                 return 0;
5795
5796         journal = EXT4_SB(sb)->s_journal;
5797
5798         if (journal) {
5799                 /* Now we set up the journal barrier. */
5800                 jbd2_journal_lock_updates(journal);
5801
5802                 /*
5803                  * Don't clear the needs_recovery flag if we failed to
5804                  * flush the journal.
5805                  */
5806                 error = jbd2_journal_flush(journal);
5807                 if (error < 0)
5808                         goto out;
5809
5810                 /* Journal blocked and flushed, clear needs_recovery flag. */
5811                 ext4_clear_feature_journal_needs_recovery(sb);
5812         }
5813
5814         error = ext4_commit_super(sb);
5815 out:
5816         if (journal)
5817                 /* we rely on upper layer to stop further updates */
5818                 jbd2_journal_unlock_updates(journal);
5819         return error;
5820 }
5821
5822 /*
5823  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5824  * flag here, even though the filesystem is not technically dirty yet.
5825  */
5826 static int ext4_unfreeze(struct super_block *sb)
5827 {
5828         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5829                 return 0;
5830
5831         if (EXT4_SB(sb)->s_journal) {
5832                 /* Reset the needs_recovery flag before the fs is unlocked. */
5833                 ext4_set_feature_journal_needs_recovery(sb);
5834         }
5835
5836         ext4_commit_super(sb);
5837         return 0;
5838 }
5839
5840 /*
5841  * Structure to save mount options for ext4_remount's benefit
5842  */
5843 struct ext4_mount_options {
5844         unsigned long s_mount_opt;
5845         unsigned long s_mount_opt2;
5846         kuid_t s_resuid;
5847         kgid_t s_resgid;
5848         unsigned long s_commit_interval;
5849         u32 s_min_batch_time, s_max_batch_time;
5850 #ifdef CONFIG_QUOTA
5851         int s_jquota_fmt;
5852         char *s_qf_names[EXT4_MAXQUOTAS];
5853 #endif
5854 };
5855
5856 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5857 {
5858         struct ext4_super_block *es;
5859         struct ext4_sb_info *sbi = EXT4_SB(sb);
5860         unsigned long old_sb_flags, vfs_flags;
5861         struct ext4_mount_options old_opts;
5862         int enable_quota = 0;
5863         ext4_group_t g;
5864         int err = 0;
5865 #ifdef CONFIG_QUOTA
5866         int i, j;
5867         char *to_free[EXT4_MAXQUOTAS];
5868 #endif
5869         char *orig_data = kstrdup(data, GFP_KERNEL);
5870         struct ext4_parsed_options parsed_opts;
5871
5872         parsed_opts.journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5873         parsed_opts.journal_devnum = 0;
5874
5875         if (data && !orig_data)
5876                 return -ENOMEM;
5877
5878         /* Store the original options */
5879         old_sb_flags = sb->s_flags;
5880         old_opts.s_mount_opt = sbi->s_mount_opt;
5881         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5882         old_opts.s_resuid = sbi->s_resuid;
5883         old_opts.s_resgid = sbi->s_resgid;
5884         old_opts.s_commit_interval = sbi->s_commit_interval;
5885         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5886         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5887 #ifdef CONFIG_QUOTA
5888         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5889         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5890                 if (sbi->s_qf_names[i]) {
5891                         char *qf_name = get_qf_name(sb, sbi, i);
5892
5893                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5894                         if (!old_opts.s_qf_names[i]) {
5895                                 for (j = 0; j < i; j++)
5896                                         kfree(old_opts.s_qf_names[j]);
5897                                 kfree(orig_data);
5898                                 return -ENOMEM;
5899                         }
5900                 } else
5901                         old_opts.s_qf_names[i] = NULL;
5902 #endif
5903         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5904                 parsed_opts.journal_ioprio =
5905                         sbi->s_journal->j_task->io_context->ioprio;
5906
5907         /*
5908          * Some options can be enabled by ext4 and/or by VFS mount flag
5909          * either way we need to make sure it matches in both *flags and
5910          * s_flags. Copy those selected flags from *flags to s_flags
5911          */
5912         vfs_flags = SB_LAZYTIME | SB_I_VERSION;
5913         sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags);
5914
5915         if (!parse_options(data, sb, &parsed_opts, 1)) {
5916                 err = -EINVAL;
5917                 goto restore_opts;
5918         }
5919
5920         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5921             test_opt(sb, JOURNAL_CHECKSUM)) {
5922                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5923                          "during remount not supported; ignoring");
5924                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5925         }
5926
5927         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5928                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5929                         ext4_msg(sb, KERN_ERR, "can't mount with "
5930                                  "both data=journal and delalloc");
5931                         err = -EINVAL;
5932                         goto restore_opts;
5933                 }
5934                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5935                         ext4_msg(sb, KERN_ERR, "can't mount with "
5936                                  "both data=journal and dioread_nolock");
5937                         err = -EINVAL;
5938                         goto restore_opts;
5939                 }
5940         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5941                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5942                         ext4_msg(sb, KERN_ERR, "can't mount with "
5943                                 "journal_async_commit in data=ordered mode");
5944                         err = -EINVAL;
5945                         goto restore_opts;
5946                 }
5947         }
5948
5949         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5950                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5951                 err = -EINVAL;
5952                 goto restore_opts;
5953         }
5954
5955         if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED))
5956                 ext4_abort(sb, EXT4_ERR_ESHUTDOWN, "Abort forced by user");
5957
5958         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5959                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5960
5961         es = sbi->s_es;
5962
5963         if (sbi->s_journal) {
5964                 ext4_init_journal_params(sb, sbi->s_journal);
5965                 set_task_ioprio(sbi->s_journal->j_task, parsed_opts.journal_ioprio);
5966         }
5967
5968         /* Flush outstanding errors before changing fs state */
5969         flush_work(&sbi->s_error_work);
5970
5971         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5972                 if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED)) {
5973                         err = -EROFS;
5974                         goto restore_opts;
5975                 }
5976
5977                 if (*flags & SB_RDONLY) {
5978                         err = sync_filesystem(sb);
5979                         if (err < 0)
5980                                 goto restore_opts;
5981                         err = dquot_suspend(sb, -1);
5982                         if (err < 0)
5983                                 goto restore_opts;
5984
5985                         /*
5986                          * First of all, the unconditional stuff we have to do
5987                          * to disable replay of the journal when we next remount
5988                          */
5989                         sb->s_flags |= SB_RDONLY;
5990
5991                         /*
5992                          * OK, test if we are remounting a valid rw partition
5993                          * readonly, and if so set the rdonly flag and then
5994                          * mark the partition as valid again.
5995                          */
5996                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5997                             (sbi->s_mount_state & EXT4_VALID_FS))
5998                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5999
6000                         if (sbi->s_journal) {
6001                                 /*
6002                                  * We let remount-ro finish even if marking fs
6003                                  * as clean failed...
6004                                  */
6005                                 ext4_mark_recovery_complete(sb, es);
6006                         }
6007                 } else {
6008                         /* Make sure we can mount this feature set readwrite */
6009                         if (ext4_has_feature_readonly(sb) ||
6010                             !ext4_feature_set_ok(sb, 0)) {
6011                                 err = -EROFS;
6012                                 goto restore_opts;
6013                         }
6014                         /*
6015                          * Make sure the group descriptor checksums
6016                          * are sane.  If they aren't, refuse to remount r/w.
6017                          */
6018                         for (g = 0; g < sbi->s_groups_count; g++) {
6019                                 struct ext4_group_desc *gdp =
6020                                         ext4_get_group_desc(sb, g, NULL);
6021
6022                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
6023                                         ext4_msg(sb, KERN_ERR,
6024                "ext4_remount: Checksum for group %u failed (%u!=%u)",
6025                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
6026                                                le16_to_cpu(gdp->bg_checksum));
6027                                         err = -EFSBADCRC;
6028                                         goto restore_opts;
6029                                 }
6030                         }
6031
6032                         /*
6033                          * If we have an unprocessed orphan list hanging
6034                          * around from a previously readonly bdev mount,
6035                          * require a full umount/remount for now.
6036                          */
6037                         if (es->s_last_orphan) {
6038                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
6039                                        "remount RDWR because of unprocessed "
6040                                        "orphan inode list.  Please "
6041                                        "umount/remount instead");
6042                                 err = -EINVAL;
6043                                 goto restore_opts;
6044                         }
6045
6046                         /*
6047                          * Mounting a RDONLY partition read-write, so reread
6048                          * and store the current valid flag.  (It may have
6049                          * been changed by e2fsck since we originally mounted
6050                          * the partition.)
6051                          */
6052                         if (sbi->s_journal) {
6053                                 err = ext4_clear_journal_err(sb, es);
6054                                 if (err)
6055                                         goto restore_opts;
6056                         }
6057                         sbi->s_mount_state = le16_to_cpu(es->s_state);
6058
6059                         err = ext4_setup_super(sb, es, 0);
6060                         if (err)
6061                                 goto restore_opts;
6062
6063                         sb->s_flags &= ~SB_RDONLY;
6064                         if (ext4_has_feature_mmp(sb))
6065                                 if (ext4_multi_mount_protect(sb,
6066                                                 le64_to_cpu(es->s_mmp_block))) {
6067                                         err = -EROFS;
6068                                         goto restore_opts;
6069                                 }
6070                         enable_quota = 1;
6071                 }
6072         }
6073
6074         /*
6075          * Reinitialize lazy itable initialization thread based on
6076          * current settings
6077          */
6078         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
6079                 ext4_unregister_li_request(sb);
6080         else {
6081                 ext4_group_t first_not_zeroed;
6082                 first_not_zeroed = ext4_has_uninit_itable(sb);
6083                 ext4_register_li_request(sb, first_not_zeroed);
6084         }
6085
6086         /*
6087          * Handle creation of system zone data early because it can fail.
6088          * Releasing of existing data is done when we are sure remount will
6089          * succeed.
6090          */
6091         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6092                 err = ext4_setup_system_zone(sb);
6093                 if (err)
6094                         goto restore_opts;
6095         }
6096
6097         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6098                 err = ext4_commit_super(sb);
6099                 if (err)
6100                         goto restore_opts;
6101         }
6102
6103 #ifdef CONFIG_QUOTA
6104         /* Release old quota file names */
6105         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6106                 kfree(old_opts.s_qf_names[i]);
6107         if (enable_quota) {
6108                 if (sb_any_quota_suspended(sb))
6109                         dquot_resume(sb, -1);
6110                 else if (ext4_has_feature_quota(sb)) {
6111                         err = ext4_enable_quotas(sb);
6112                         if (err)
6113                                 goto restore_opts;
6114                 }
6115         }
6116 #endif
6117         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6118                 ext4_release_system_zone(sb);
6119
6120         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6121                 ext4_stop_mmpd(sbi);
6122
6123         /*
6124          * Some options can be enabled by ext4 and/or by VFS mount flag
6125          * either way we need to make sure it matches in both *flags and
6126          * s_flags. Copy those selected flags from s_flags to *flags
6127          */
6128         *flags = (*flags & ~vfs_flags) | (sb->s_flags & vfs_flags);
6129
6130         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s. Quota mode: %s.",
6131                  orig_data, ext4_quota_mode(sb));
6132         kfree(orig_data);
6133         return 0;
6134
6135 restore_opts:
6136         sb->s_flags = old_sb_flags;
6137         sbi->s_mount_opt = old_opts.s_mount_opt;
6138         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6139         sbi->s_resuid = old_opts.s_resuid;
6140         sbi->s_resgid = old_opts.s_resgid;
6141         sbi->s_commit_interval = old_opts.s_commit_interval;
6142         sbi->s_min_batch_time = old_opts.s_min_batch_time;
6143         sbi->s_max_batch_time = old_opts.s_max_batch_time;
6144         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6145                 ext4_release_system_zone(sb);
6146 #ifdef CONFIG_QUOTA
6147         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6148         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6149                 to_free[i] = get_qf_name(sb, sbi, i);
6150                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6151         }
6152         synchronize_rcu();
6153         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6154                 kfree(to_free[i]);
6155 #endif
6156         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6157                 ext4_stop_mmpd(sbi);
6158         kfree(orig_data);
6159         return err;
6160 }
6161
6162 #ifdef CONFIG_QUOTA
6163 static int ext4_statfs_project(struct super_block *sb,
6164                                kprojid_t projid, struct kstatfs *buf)
6165 {
6166         struct kqid qid;
6167         struct dquot *dquot;
6168         u64 limit;
6169         u64 curblock;
6170
6171         qid = make_kqid_projid(projid);
6172         dquot = dqget(sb, qid);
6173         if (IS_ERR(dquot))
6174                 return PTR_ERR(dquot);
6175         spin_lock(&dquot->dq_dqb_lock);
6176
6177         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6178                              dquot->dq_dqb.dqb_bhardlimit);
6179         limit >>= sb->s_blocksize_bits;
6180
6181         if (limit && buf->f_blocks > limit) {
6182                 curblock = (dquot->dq_dqb.dqb_curspace +
6183                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6184                 buf->f_blocks = limit;
6185                 buf->f_bfree = buf->f_bavail =
6186                         (buf->f_blocks > curblock) ?
6187                          (buf->f_blocks - curblock) : 0;
6188         }
6189
6190         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6191                              dquot->dq_dqb.dqb_ihardlimit);
6192         if (limit && buf->f_files > limit) {
6193                 buf->f_files = limit;
6194                 buf->f_ffree =
6195                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6196                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6197         }
6198
6199         spin_unlock(&dquot->dq_dqb_lock);
6200         dqput(dquot);
6201         return 0;
6202 }
6203 #endif
6204
6205 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6206 {
6207         struct super_block *sb = dentry->d_sb;
6208         struct ext4_sb_info *sbi = EXT4_SB(sb);
6209         struct ext4_super_block *es = sbi->s_es;
6210         ext4_fsblk_t overhead = 0, resv_blocks;
6211         s64 bfree;
6212         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6213
6214         if (!test_opt(sb, MINIX_DF))
6215                 overhead = sbi->s_overhead;
6216
6217         buf->f_type = EXT4_SUPER_MAGIC;
6218         buf->f_bsize = sb->s_blocksize;
6219         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6220         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6221                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6222         /* prevent underflow in case that few free space is available */
6223         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6224         buf->f_bavail = buf->f_bfree -
6225                         (ext4_r_blocks_count(es) + resv_blocks);
6226         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6227                 buf->f_bavail = 0;
6228         buf->f_files = le32_to_cpu(es->s_inodes_count);
6229         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6230         buf->f_namelen = EXT4_NAME_LEN;
6231         buf->f_fsid = uuid_to_fsid(es->s_uuid);
6232
6233 #ifdef CONFIG_QUOTA
6234         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6235             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6236                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6237 #endif
6238         return 0;
6239 }
6240
6241
6242 #ifdef CONFIG_QUOTA
6243
6244 /*
6245  * Helper functions so that transaction is started before we acquire dqio_sem
6246  * to keep correct lock ordering of transaction > dqio_sem
6247  */
6248 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6249 {
6250         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6251 }
6252
6253 static int ext4_write_dquot(struct dquot *dquot)
6254 {
6255         int ret, err;
6256         handle_t *handle;
6257         struct inode *inode;
6258
6259         inode = dquot_to_inode(dquot);
6260         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6261                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6262         if (IS_ERR(handle))
6263                 return PTR_ERR(handle);
6264         ret = dquot_commit(dquot);
6265         err = ext4_journal_stop(handle);
6266         if (!ret)
6267                 ret = err;
6268         return ret;
6269 }
6270
6271 static int ext4_acquire_dquot(struct dquot *dquot)
6272 {
6273         int ret, err;
6274         handle_t *handle;
6275
6276         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6277                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6278         if (IS_ERR(handle))
6279                 return PTR_ERR(handle);
6280         ret = dquot_acquire(dquot);
6281         err = ext4_journal_stop(handle);
6282         if (!ret)
6283                 ret = err;
6284         return ret;
6285 }
6286
6287 static int ext4_release_dquot(struct dquot *dquot)
6288 {
6289         int ret, err;
6290         handle_t *handle;
6291
6292         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6293                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6294         if (IS_ERR(handle)) {
6295                 /* Release dquot anyway to avoid endless cycle in dqput() */
6296                 dquot_release(dquot);
6297                 return PTR_ERR(handle);
6298         }
6299         ret = dquot_release(dquot);
6300         err = ext4_journal_stop(handle);
6301         if (!ret)
6302                 ret = err;
6303         return ret;
6304 }
6305
6306 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6307 {
6308         struct super_block *sb = dquot->dq_sb;
6309
6310         if (ext4_is_quota_journalled(sb)) {
6311                 dquot_mark_dquot_dirty(dquot);
6312                 return ext4_write_dquot(dquot);
6313         } else {
6314                 return dquot_mark_dquot_dirty(dquot);
6315         }
6316 }
6317
6318 static int ext4_write_info(struct super_block *sb, int type)
6319 {
6320         int ret, err;
6321         handle_t *handle;
6322
6323         /* Data block + inode block */
6324         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
6325         if (IS_ERR(handle))
6326                 return PTR_ERR(handle);
6327         ret = dquot_commit_info(sb, type);
6328         err = ext4_journal_stop(handle);
6329         if (!ret)
6330                 ret = err;
6331         return ret;
6332 }
6333
6334 /*
6335  * Turn on quotas during mount time - we need to find
6336  * the quota file and such...
6337  */
6338 static int ext4_quota_on_mount(struct super_block *sb, int type)
6339 {
6340         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
6341                                         EXT4_SB(sb)->s_jquota_fmt, type);
6342 }
6343
6344 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6345 {
6346         struct ext4_inode_info *ei = EXT4_I(inode);
6347
6348         /* The first argument of lockdep_set_subclass has to be
6349          * *exactly* the same as the argument to init_rwsem() --- in
6350          * this case, in init_once() --- or lockdep gets unhappy
6351          * because the name of the lock is set using the
6352          * stringification of the argument to init_rwsem().
6353          */
6354         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6355         lockdep_set_subclass(&ei->i_data_sem, subclass);
6356 }
6357
6358 /*
6359  * Standard function to be called on quota_on
6360  */
6361 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6362                          const struct path *path)
6363 {
6364         int err;
6365
6366         if (!test_opt(sb, QUOTA))
6367                 return -EINVAL;
6368
6369         /* Quotafile not on the same filesystem? */
6370         if (path->dentry->d_sb != sb)
6371                 return -EXDEV;
6372
6373         /* Quota already enabled for this file? */
6374         if (IS_NOQUOTA(d_inode(path->dentry)))
6375                 return -EBUSY;
6376
6377         /* Journaling quota? */
6378         if (EXT4_SB(sb)->s_qf_names[type]) {
6379                 /* Quotafile not in fs root? */
6380                 if (path->dentry->d_parent != sb->s_root)
6381                         ext4_msg(sb, KERN_WARNING,
6382                                 "Quota file not on filesystem root. "
6383                                 "Journaled quota will not work");
6384                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6385         } else {
6386                 /*
6387                  * Clear the flag just in case mount options changed since
6388                  * last time.
6389                  */
6390                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6391         }
6392
6393         /*
6394          * When we journal data on quota file, we have to flush journal to see
6395          * all updates to the file when we bypass pagecache...
6396          */
6397         if (EXT4_SB(sb)->s_journal &&
6398             ext4_should_journal_data(d_inode(path->dentry))) {
6399                 /*
6400                  * We don't need to lock updates but journal_flush() could
6401                  * otherwise be livelocked...
6402                  */
6403                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6404                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
6405                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6406                 if (err)
6407                         return err;
6408         }
6409
6410         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6411         err = dquot_quota_on(sb, type, format_id, path);
6412         if (err) {
6413                 lockdep_set_quota_inode(path->dentry->d_inode,
6414                                              I_DATA_SEM_NORMAL);
6415         } else {
6416                 struct inode *inode = d_inode(path->dentry);
6417                 handle_t *handle;
6418
6419                 /*
6420                  * Set inode flags to prevent userspace from messing with quota
6421                  * files. If this fails, we return success anyway since quotas
6422                  * are already enabled and this is not a hard failure.
6423                  */
6424                 inode_lock(inode);
6425                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6426                 if (IS_ERR(handle))
6427                         goto unlock_inode;
6428                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6429                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6430                                 S_NOATIME | S_IMMUTABLE);
6431                 err = ext4_mark_inode_dirty(handle, inode);
6432                 ext4_journal_stop(handle);
6433         unlock_inode:
6434                 inode_unlock(inode);
6435         }
6436         return err;
6437 }
6438
6439 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6440                              unsigned int flags)
6441 {
6442         int err;
6443         struct inode *qf_inode;
6444         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6445                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6446                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6447                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6448         };
6449
6450         BUG_ON(!ext4_has_feature_quota(sb));
6451
6452         if (!qf_inums[type])
6453                 return -EPERM;
6454
6455         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6456         if (IS_ERR(qf_inode)) {
6457                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6458                 return PTR_ERR(qf_inode);
6459         }
6460
6461         /* Don't account quota for quota files to avoid recursion */
6462         qf_inode->i_flags |= S_NOQUOTA;
6463         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6464         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6465         if (err)
6466                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6467         iput(qf_inode);
6468
6469         return err;
6470 }
6471
6472 /* Enable usage tracking for all quota types. */
6473 static int ext4_enable_quotas(struct super_block *sb)
6474 {
6475         int type, err = 0;
6476         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6477                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6478                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6479                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6480         };
6481         bool quota_mopt[EXT4_MAXQUOTAS] = {
6482                 test_opt(sb, USRQUOTA),
6483                 test_opt(sb, GRPQUOTA),
6484                 test_opt(sb, PRJQUOTA),
6485         };
6486
6487         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6488         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6489                 if (qf_inums[type]) {
6490                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6491                                 DQUOT_USAGE_ENABLED |
6492                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6493                         if (err) {
6494                                 ext4_warning(sb,
6495                                         "Failed to enable quota tracking "
6496                                         "(type=%d, err=%d). Please run "
6497                                         "e2fsck to fix.", type, err);
6498                                 for (type--; type >= 0; type--)
6499                                         dquot_quota_off(sb, type);
6500
6501                                 return err;
6502                         }
6503                 }
6504         }
6505         return 0;
6506 }
6507
6508 static int ext4_quota_off(struct super_block *sb, int type)
6509 {
6510         struct inode *inode = sb_dqopt(sb)->files[type];
6511         handle_t *handle;
6512         int err;
6513
6514         /* Force all delayed allocation blocks to be allocated.
6515          * Caller already holds s_umount sem */
6516         if (test_opt(sb, DELALLOC))
6517                 sync_filesystem(sb);
6518
6519         if (!inode || !igrab(inode))
6520                 goto out;
6521
6522         err = dquot_quota_off(sb, type);
6523         if (err || ext4_has_feature_quota(sb))
6524                 goto out_put;
6525
6526         inode_lock(inode);
6527         /*
6528          * Update modification times of quota files when userspace can
6529          * start looking at them. If we fail, we return success anyway since
6530          * this is not a hard failure and quotas are already disabled.
6531          */
6532         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6533         if (IS_ERR(handle)) {
6534                 err = PTR_ERR(handle);
6535                 goto out_unlock;
6536         }
6537         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6538         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6539         inode->i_mtime = inode->i_ctime = current_time(inode);
6540         err = ext4_mark_inode_dirty(handle, inode);
6541         ext4_journal_stop(handle);
6542 out_unlock:
6543         inode_unlock(inode);
6544 out_put:
6545         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6546         iput(inode);
6547         return err;
6548 out:
6549         return dquot_quota_off(sb, type);
6550 }
6551
6552 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6553  * acquiring the locks... As quota files are never truncated and quota code
6554  * itself serializes the operations (and no one else should touch the files)
6555  * we don't have to be afraid of races */
6556 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6557                                size_t len, loff_t off)
6558 {
6559         struct inode *inode = sb_dqopt(sb)->files[type];
6560         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6561         int offset = off & (sb->s_blocksize - 1);
6562         int tocopy;
6563         size_t toread;
6564         struct buffer_head *bh;
6565         loff_t i_size = i_size_read(inode);
6566
6567         if (off > i_size)
6568                 return 0;
6569         if (off+len > i_size)
6570                 len = i_size-off;
6571         toread = len;
6572         while (toread > 0) {
6573                 tocopy = sb->s_blocksize - offset < toread ?
6574                                 sb->s_blocksize - offset : toread;
6575                 bh = ext4_bread(NULL, inode, blk, 0);
6576                 if (IS_ERR(bh))
6577                         return PTR_ERR(bh);
6578                 if (!bh)        /* A hole? */
6579                         memset(data, 0, tocopy);
6580                 else
6581                         memcpy(data, bh->b_data+offset, tocopy);
6582                 brelse(bh);
6583                 offset = 0;
6584                 toread -= tocopy;
6585                 data += tocopy;
6586                 blk++;
6587         }
6588         return len;
6589 }
6590
6591 /* Write to quotafile (we know the transaction is already started and has
6592  * enough credits) */
6593 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6594                                 const char *data, size_t len, loff_t off)
6595 {
6596         struct inode *inode = sb_dqopt(sb)->files[type];
6597         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6598         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6599         int retries = 0;
6600         struct buffer_head *bh;
6601         handle_t *handle = journal_current_handle();
6602
6603         if (EXT4_SB(sb)->s_journal && !handle) {
6604                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6605                         " cancelled because transaction is not started",
6606                         (unsigned long long)off, (unsigned long long)len);
6607                 return -EIO;
6608         }
6609         /*
6610          * Since we account only one data block in transaction credits,
6611          * then it is impossible to cross a block boundary.
6612          */
6613         if (sb->s_blocksize - offset < len) {
6614                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6615                         " cancelled because not block aligned",
6616                         (unsigned long long)off, (unsigned long long)len);
6617                 return -EIO;
6618         }
6619
6620         do {
6621                 bh = ext4_bread(handle, inode, blk,
6622                                 EXT4_GET_BLOCKS_CREATE |
6623                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6624         } while (PTR_ERR(bh) == -ENOSPC &&
6625                  ext4_should_retry_alloc(inode->i_sb, &retries));
6626         if (IS_ERR(bh))
6627                 return PTR_ERR(bh);
6628         if (!bh)
6629                 goto out;
6630         BUFFER_TRACE(bh, "get write access");
6631         err = ext4_journal_get_write_access(handle, bh);
6632         if (err) {
6633                 brelse(bh);
6634                 return err;
6635         }
6636         lock_buffer(bh);
6637         memcpy(bh->b_data+offset, data, len);
6638         flush_dcache_page(bh->b_page);
6639         unlock_buffer(bh);
6640         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6641         brelse(bh);
6642 out:
6643         if (inode->i_size < off + len) {
6644                 i_size_write(inode, off + len);
6645                 EXT4_I(inode)->i_disksize = inode->i_size;
6646                 err2 = ext4_mark_inode_dirty(handle, inode);
6647                 if (unlikely(err2 && !err))
6648                         err = err2;
6649         }
6650         return err ? err : len;
6651 }
6652 #endif
6653
6654 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6655                        const char *dev_name, void *data)
6656 {
6657         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6658 }
6659
6660 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6661 static inline void register_as_ext2(void)
6662 {
6663         int err = register_filesystem(&ext2_fs_type);
6664         if (err)
6665                 printk(KERN_WARNING
6666                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6667 }
6668
6669 static inline void unregister_as_ext2(void)
6670 {
6671         unregister_filesystem(&ext2_fs_type);
6672 }
6673
6674 static inline int ext2_feature_set_ok(struct super_block *sb)
6675 {
6676         if (ext4_has_unknown_ext2_incompat_features(sb))
6677                 return 0;
6678         if (sb_rdonly(sb))
6679                 return 1;
6680         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6681                 return 0;
6682         return 1;
6683 }
6684 #else
6685 static inline void register_as_ext2(void) { }
6686 static inline void unregister_as_ext2(void) { }
6687 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6688 #endif
6689
6690 static inline void register_as_ext3(void)
6691 {
6692         int err = register_filesystem(&ext3_fs_type);
6693         if (err)
6694                 printk(KERN_WARNING
6695                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6696 }
6697
6698 static inline void unregister_as_ext3(void)
6699 {
6700         unregister_filesystem(&ext3_fs_type);
6701 }
6702
6703 static inline int ext3_feature_set_ok(struct super_block *sb)
6704 {
6705         if (ext4_has_unknown_ext3_incompat_features(sb))
6706                 return 0;
6707         if (!ext4_has_feature_journal(sb))
6708                 return 0;
6709         if (sb_rdonly(sb))
6710                 return 1;
6711         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6712                 return 0;
6713         return 1;
6714 }
6715
6716 static struct file_system_type ext4_fs_type = {
6717         .owner          = THIS_MODULE,
6718         .name           = "ext4",
6719         .mount          = ext4_mount,
6720         .kill_sb        = kill_block_super,
6721         .fs_flags       = FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
6722 };
6723 MODULE_ALIAS_FS("ext4");
6724
6725 /* Shared across all ext4 file systems */
6726 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6727
6728 static int __init ext4_init_fs(void)
6729 {
6730         int i, err;
6731
6732         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6733         ext4_li_info = NULL;
6734
6735         /* Build-time check for flags consistency */
6736         ext4_check_flag_values();
6737
6738         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6739                 init_waitqueue_head(&ext4__ioend_wq[i]);
6740
6741         err = ext4_init_es();
6742         if (err)
6743                 return err;
6744
6745         err = ext4_init_pending();
6746         if (err)
6747                 goto out7;
6748
6749         err = ext4_init_post_read_processing();
6750         if (err)
6751                 goto out6;
6752
6753         err = ext4_init_pageio();
6754         if (err)
6755                 goto out5;
6756
6757         err = ext4_init_system_zone();
6758         if (err)
6759                 goto out4;
6760
6761         err = ext4_init_sysfs();
6762         if (err)
6763                 goto out3;
6764
6765         err = ext4_init_mballoc();
6766         if (err)
6767                 goto out2;
6768         err = init_inodecache();
6769         if (err)
6770                 goto out1;
6771
6772         err = ext4_fc_init_dentry_cache();
6773         if (err)
6774                 goto out05;
6775
6776         register_as_ext3();
6777         register_as_ext2();
6778         err = register_filesystem(&ext4_fs_type);
6779         if (err)
6780                 goto out;
6781
6782         return 0;
6783 out:
6784         unregister_as_ext2();
6785         unregister_as_ext3();
6786 out05:
6787         destroy_inodecache();
6788 out1:
6789         ext4_exit_mballoc();
6790 out2:
6791         ext4_exit_sysfs();
6792 out3:
6793         ext4_exit_system_zone();
6794 out4:
6795         ext4_exit_pageio();
6796 out5:
6797         ext4_exit_post_read_processing();
6798 out6:
6799         ext4_exit_pending();
6800 out7:
6801         ext4_exit_es();
6802
6803         return err;
6804 }
6805
6806 static void __exit ext4_exit_fs(void)
6807 {
6808         ext4_destroy_lazyinit_thread();
6809         unregister_as_ext2();
6810         unregister_as_ext3();
6811         unregister_filesystem(&ext4_fs_type);
6812         destroy_inodecache();
6813         ext4_exit_mballoc();
6814         ext4_exit_sysfs();
6815         ext4_exit_system_zone();
6816         ext4_exit_pageio();
6817         ext4_exit_post_read_processing();
6818         ext4_exit_es();
6819         ext4_exit_pending();
6820 }
6821
6822 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6823 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6824 MODULE_LICENSE("GPL");
6825 MODULE_SOFTDEP("pre: crc32c");
6826 module_init(ext4_init_fs)
6827 module_exit(ext4_exit_fs)