fs/ext4/super.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/ext4/super.c
   4  *
   5  * Copyright (C) 1992, 1993, 1994, 1995
   6  * Remy Card (card@masi.ibp.fr)
   7  * Laboratoire MASI - Institut Blaise Pascal
   8  * Universite Pierre et Marie Curie (Paris VI)
   9  *
  10  *  from
  11  *
  12  *  linux/fs/minix/inode.c
  13  *
  14  *  Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  *  Big-endian to little-endian byte-swapping/bitmaps by
  17  *        David S. Miller (davem@caip.rutgers.edu), 1995
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/string.h>
  22 #include <linux/fs.h>
  23 #include <linux/time.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/backing-dev.h>
  29 #include <linux/parser.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/dax.h>
  42 #include <linux/cleancache.h>
  43 #include <linux/uaccess.h>
  44 #include <linux/iversion.h>
  45 #include <linux/unicode.h>
  46
  47 #include <linux/kthread.h>
  48 #include <linux/freezer.h>
  49
  50 #include "ext4.h"
  51 #include "ext4_extents.h"       /* Needed for trace points definition */
  52 #include "ext4_jbd2.h"
  53 #include "xattr.h"
  54 #include "acl.h"
  55 #include "mballoc.h"
  56 #include "fsmap.h"
  57
  58 #define CREATE_TRACE_POINTS
  59 #include <trace/events/ext4.h>
  60
  61 static struct ext4_lazy_init *ext4_li_info;
  62 static struct mutex ext4_li_mtx;
  63 static struct ratelimit_state ext4_mount_msg_ratelimit;
  64
  65 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  66                              unsigned long journal_devnum);
  67 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  68 static int ext4_commit_super(struct super_block *sb, int sync);
  69 static void ext4_mark_recovery_complete(struct super_block *sb,
  70                                         struct ext4_super_block *es);
  71 static void ext4_clear_journal_err(struct super_block *sb,
  72                                    struct ext4_super_block *es);
  73 static int ext4_sync_fs(struct super_block *sb, int wait);
  74 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  75 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  76 static int ext4_unfreeze(struct super_block *sb);
  77 static int ext4_freeze(struct super_block *sb);
  78 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  79                        const char *dev_name, void *data);
  80 static inline int ext2_feature_set_ok(struct super_block *sb);
  81 static inline int ext3_feature_set_ok(struct super_block *sb);
  82 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  83 static void ext4_destroy_lazyinit_thread(void);
  84 static void ext4_unregister_li_request(struct super_block *sb);
  85 static void ext4_clear_request_list(void);
  86 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  87                                             unsigned int journal_inum);
  88
  89 /*
  90  * Lock ordering
  91  *
  92  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
  93  * i_mmap_rwsem (inode->i_mmap_rwsem)!
  94  *
  95  * page fault path:
  96  * mmap_sem -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
  97  *   page lock -> i_data_sem (rw)
  98  *
  99  * buffered write path:
 100  * sb_start_write -> i_mutex -> mmap_sem
 101  * sb_start_write -> i_mutex -> transaction start -> page lock ->
 102  *   i_data_sem (rw)
 103  *
 104  * truncate:
 105  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> i_mmap_rwsem (w) -> page lock
 106  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> transaction start ->
 107  *   i_data_sem (rw)
 108  *
 109  * direct IO:
 110  * sb_start_write -> i_mutex -> mmap_sem
 111  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
 112  *
 113  * writepages:
 114  * transaction start -> page lock(s) -> i_data_sem (rw)
 115  */
 116
 117 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 118 static struct file_system_type ext2_fs_type = {
 119         .owner          = THIS_MODULE,
 120         .name           = "ext2",
 121         .mount          = ext4_mount,
 122         .kill_sb        = kill_block_super,
 123         .fs_flags       = FS_REQUIRES_DEV,
 124 };
 125 MODULE_ALIAS_FS("ext2");
 126 MODULE_ALIAS("ext2");
 127 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
 128 #else
 129 #define IS_EXT2_SB(sb) (0)
 130 #endif
 131
 132
 133 static struct file_system_type ext3_fs_type = {
 134         .owner          = THIS_MODULE,
 135         .name           = "ext3",
 136         .mount          = ext4_mount,
 137         .kill_sb        = kill_block_super,
 138         .fs_flags       = FS_REQUIRES_DEV,
 139 };
 140 MODULE_ALIAS_FS("ext3");
 141 MODULE_ALIAS("ext3");
 142 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 143
 144 /*
 145  * This works like sb_bread() except it uses ERR_PTR for error
 146  * returns.  Currently with sb_bread it's impossible to distinguish
 147  * between ENOMEM and EIO situations (since both result in a NULL
 148  * return.
 149  */
 150 struct buffer_head *
 151 ext4_sb_bread(struct super_block *sb, sector_t block, int op_flags)
 152 {
 153         struct buffer_head *bh = sb_getblk(sb, block);
 154
 155         if (bh == NULL)
 156                 return ERR_PTR(-ENOMEM);
 157         if (buffer_uptodate(bh))
 158                 return bh;
 159         ll_rw_block(REQ_OP_READ, REQ_META | op_flags, 1, &bh);
 160         wait_on_buffer(bh);
 161         if (buffer_uptodate(bh))
 162                 return bh;
 163         put_bh(bh);
 164         return ERR_PTR(-EIO);
 165 }
 166
 167 static int ext4_verify_csum_type(struct super_block *sb,
 168                                  struct ext4_super_block *es)
 169 {
 170         if (!ext4_has_feature_metadata_csum(sb))
 171                 return 1;
 172
 173         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 174 }
 175
 176 static __le32 ext4_superblock_csum(struct super_block *sb,
 177                                    struct ext4_super_block *es)
 178 {
 179         struct ext4_sb_info *sbi = EXT4_SB(sb);
 180         int offset = offsetof(struct ext4_super_block, s_checksum);
 181         __u32 csum;
 182
 183         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 184
 185         return cpu_to_le32(csum);
 186 }
 187
 188 static int ext4_superblock_csum_verify(struct super_block *sb,
 189                                        struct ext4_super_block *es)
 190 {
 191         if (!ext4_has_metadata_csum(sb))
 192                 return 1;
 193
 194         return es->s_checksum == ext4_superblock_csum(sb, es);
 195 }
 196
 197 void ext4_superblock_csum_set(struct super_block *sb)
 198 {
 199         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 200
 201         if (!ext4_has_metadata_csum(sb))
 202                 return;
 203
 204         es->s_checksum = ext4_superblock_csum(sb, es);
 205 }
 206
 207 void *ext4_kvmalloc(size_t size, gfp_t flags)
 208 {
 209         void *ret;
 210
 211         ret = kmalloc(size, flags | __GFP_NOWARN);
 212         if (!ret)
 213                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 214         return ret;
 215 }
 216
 217 void *ext4_kvzalloc(size_t size, gfp_t flags)
 218 {
 219         void *ret;
 220
 221         ret = kzalloc(size, flags | __GFP_NOWARN);
 222         if (!ret)
 223                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 224         return ret;
 225 }
 226
 227 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 228                                struct ext4_group_desc *bg)
 229 {
 230         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 231                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 232                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 233 }
 234
 235 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 236                                struct ext4_group_desc *bg)
 237 {
 238         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 239                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 240                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 241 }
 242
 243 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 244                               struct ext4_group_desc *bg)
 245 {
 246         return le32_to_cpu(bg->bg_inode_table_lo) |
 247                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 248                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 249 }
 250
 251 __u32 ext4_free_group_clusters(struct super_block *sb,
 252                                struct ext4_group_desc *bg)
 253 {
 254         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 255                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 256                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 257 }
 258
 259 __u32 ext4_free_inodes_count(struct super_block *sb,
 260                               struct ext4_group_desc *bg)
 261 {
 262         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 263                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 264                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 265 }
 266
 267 __u32 ext4_used_dirs_count(struct super_block *sb,
 268                               struct ext4_group_desc *bg)
 269 {
 270         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 271                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 272                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 273 }
 274
 275 __u32 ext4_itable_unused_count(struct super_block *sb,
 276                               struct ext4_group_desc *bg)
 277 {
 278         return le16_to_cpu(bg->bg_itable_unused_lo) |
 279                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 280                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 281 }
 282
 283 void ext4_block_bitmap_set(struct super_block *sb,
 284                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 285 {
 286         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 287         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 288                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 289 }
 290
 291 void ext4_inode_bitmap_set(struct super_block *sb,
 292                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 293 {
 294         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 295         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 296                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 297 }
 298
 299 void ext4_inode_table_set(struct super_block *sb,
 300                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 301 {
 302         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 303         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 304                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 305 }
 306
 307 void ext4_free_group_clusters_set(struct super_block *sb,
 308                                   struct ext4_group_desc *bg, __u32 count)
 309 {
 310         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 311         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 312                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 313 }
 314
 315 void ext4_free_inodes_set(struct super_block *sb,
 316                           struct ext4_group_desc *bg, __u32 count)
 317 {
 318         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 319         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 320                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 321 }
 322
 323 void ext4_used_dirs_set(struct super_block *sb,
 324                           struct ext4_group_desc *bg, __u32 count)
 325 {
 326         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 327         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 328                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 329 }
 330
 331 void ext4_itable_unused_set(struct super_block *sb,
 332                           struct ext4_group_desc *bg, __u32 count)
 333 {
 334         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 335         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 336                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 337 }
 338
 339 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi)
 340 {
 341         time64_t now = ktime_get_real_seconds();
 342
 343         now = clamp_val(now, 0, (1ull << 40) - 1);
 344
 345         *lo = cpu_to_le32(lower_32_bits(now));
 346         *hi = upper_32_bits(now);
 347 }
 348
 349 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 350 {
 351         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 352 }
 353 #define ext4_update_tstamp(es, tstamp) \
 354         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 355 #define ext4_get_tstamp(es, tstamp) \
 356         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 357
 358 static void __save_error_info(struct super_block *sb, const char *func,
 359                             unsigned int line)
 360 {
 361         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 362
 363         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 364         if (bdev_read_only(sb->s_bdev))
 365                 return;
 366         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 367         ext4_update_tstamp(es, s_last_error_time);
 368         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 369         es->s_last_error_line = cpu_to_le32(line);
 370         if (!es->s_first_error_time) {
 371                 es->s_first_error_time = es->s_last_error_time;
 372                 es->s_first_error_time_hi = es->s_last_error_time_hi;
 373                 strncpy(es->s_first_error_func, func,
 374                         sizeof(es->s_first_error_func));
 375                 es->s_first_error_line = cpu_to_le32(line);
 376                 es->s_first_error_ino = es->s_last_error_ino;
 377                 es->s_first_error_block = es->s_last_error_block;
 378         }
 379         /*
 380          * Start the daily error reporting function if it hasn't been
 381          * started already
 382          */
 383         if (!es->s_error_count)
 384                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 385         le32_add_cpu(&es->s_error_count, 1);
 386 }
 387
 388 static void save_error_info(struct super_block *sb, const char *func,
 389                             unsigned int line)
 390 {
 391         __save_error_info(sb, func, line);
 392         ext4_commit_super(sb, 1);
 393 }
 394
 395 /*
 396  * The del_gendisk() function uninitializes the disk-specific data
 397  * structures, including the bdi structure, without telling anyone
 398  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 399  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 400  * This is a kludge to prevent these oops until we can put in a proper
 401  * hook in del_gendisk() to inform the VFS and file system layers.
 402  */
 403 static int block_device_ejected(struct super_block *sb)
 404 {
 405         struct inode *bd_inode = sb->s_bdev->bd_inode;
 406         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 407
 408         return bdi->dev == NULL;
 409 }
 410
 411 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 412 {
 413         struct super_block              *sb = journal->j_private;
 414         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 415         int                             error = is_journal_aborted(journal);
 416         struct ext4_journal_cb_entry    *jce;
 417
 418         BUG_ON(txn->t_state == T_FINISHED);
 419
 420         ext4_process_freed_data(sb, txn->t_tid);
 421
 422         spin_lock(&sbi->s_md_lock);
 423         while (!list_empty(&txn->t_private_list)) {
 424                 jce = list_entry(txn->t_private_list.next,
 425                                  struct ext4_journal_cb_entry, jce_list);
 426                 list_del_init(&jce->jce_list);
 427                 spin_unlock(&sbi->s_md_lock);
 428                 jce->jce_func(sb, jce, error);
 429                 spin_lock(&sbi->s_md_lock);
 430         }
 431         spin_unlock(&sbi->s_md_lock);
 432 }
 433
 434 static bool system_going_down(void)
 435 {
 436         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 437                 || system_state == SYSTEM_RESTART;
 438 }
 439
 440 /* Deal with the reporting of failure conditions on a filesystem such as
 441  * inconsistencies detected or read IO failures.
 442  *
 443  * On ext2, we can store the error state of the filesystem in the
 444  * superblock.  That is not possible on ext4, because we may have other
 445  * write ordering constraints on the superblock which prevent us from
 446  * writing it out straight away; and given that the journal is about to
 447  * be aborted, we can't rely on the current, or future, transactions to
 448  * write out the superblock safely.
 449  *
 450  * We'll just use the jbd2_journal_abort() error code to record an error in
 451  * the journal instead.  On recovery, the journal will complain about
 452  * that error until we've noted it down and cleared it.
 453  */
 454
 455 static void ext4_handle_error(struct super_block *sb)
 456 {
 457         if (test_opt(sb, WARN_ON_ERROR))
 458                 WARN_ON_ONCE(1);
 459
 460         if (sb_rdonly(sb))
 461                 return;
 462
 463         if (!test_opt(sb, ERRORS_CONT)) {
 464                 journal_t *journal = EXT4_SB(sb)->s_journal;
 465
 466                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 467                 if (journal)
 468                         jbd2_journal_abort(journal, -EIO);
 469         }
 470         /*
 471          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 472          * could panic during 'reboot -f' as the underlying device got already
 473          * disabled.
 474          */
 475         if (test_opt(sb, ERRORS_RO) || system_going_down()) {
 476                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 477                 /*
 478                  * Make sure updated value of ->s_mount_flags will be visible
 479                  * before ->s_flags update
 480                  */
 481                 smp_wmb();
 482                 sb->s_flags |= SB_RDONLY;
 483         } else if (test_opt(sb, ERRORS_PANIC)) {
 484                 if (EXT4_SB(sb)->s_journal &&
 485                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 486                         return;
 487                 panic("EXT4-fs (device %s): panic forced after error\n",
 488                         sb->s_id);
 489         }
 490 }
 491
 492 #define ext4_error_ratelimit(sb)                                        \
 493                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 494                              "EXT4-fs error")
 495
 496 void __ext4_error(struct super_block *sb, const char *function,
 497                   unsigned int line, const char *fmt, ...)
 498 {
 499         struct va_format vaf;
 500         va_list args;
 501
 502         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 503                 return;
 504
 505         trace_ext4_error(sb, function, line);
 506         if (ext4_error_ratelimit(sb)) {
 507                 va_start(args, fmt);
 508                 vaf.fmt = fmt;
 509                 vaf.va = &args;
 510                 printk(KERN_CRIT
 511                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 512                        sb->s_id, function, line, current->comm, &vaf);
 513                 va_end(args);
 514         }
 515         save_error_info(sb, function, line);
 516         ext4_handle_error(sb);
 517 }
 518
 519 void __ext4_error_inode(struct inode *inode, const char *function,
 520                         unsigned int line, ext4_fsblk_t block,
 521                         const char *fmt, ...)
 522 {
 523         va_list args;
 524         struct va_format vaf;
 525         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 526
 527         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 528                 return;
 529
 530         trace_ext4_error(inode->i_sb, function, line);
 531         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 532         es->s_last_error_block = cpu_to_le64(block);
 533         if (ext4_error_ratelimit(inode->i_sb)) {
 534                 va_start(args, fmt);
 535                 vaf.fmt = fmt;
 536                 vaf.va = &args;
 537                 if (block)
 538                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 539                                "inode #%lu: block %llu: comm %s: %pV\n",
 540                                inode->i_sb->s_id, function, line, inode->i_ino,
 541                                block, current->comm, &vaf);
 542                 else
 543                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 544                                "inode #%lu: comm %s: %pV\n",
 545                                inode->i_sb->s_id, function, line, inode->i_ino,
 546                                current->comm, &vaf);
 547                 va_end(args);
 548         }
 549         save_error_info(inode->i_sb, function, line);
 550         ext4_handle_error(inode->i_sb);
 551 }
 552
 553 void __ext4_error_file(struct file *file, const char *function,
 554                        unsigned int line, ext4_fsblk_t block,
 555                        const char *fmt, ...)
 556 {
 557         va_list args;
 558         struct va_format vaf;
 559         struct ext4_super_block *es;
 560         struct inode *inode = file_inode(file);
 561         char pathname[80], *path;
 562
 563         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 564                 return;
 565
 566         trace_ext4_error(inode->i_sb, function, line);
 567         es = EXT4_SB(inode->i_sb)->s_es;
 568         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 569         if (ext4_error_ratelimit(inode->i_sb)) {
 570                 path = file_path(file, pathname, sizeof(pathname));
 571                 if (IS_ERR(path))
 572                         path = "(unknown)";
 573                 va_start(args, fmt);
 574                 vaf.fmt = fmt;
 575                 vaf.va = &args;
 576                 if (block)
 577                         printk(KERN_CRIT
 578                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 579                                "block %llu: comm %s: path %s: %pV\n",
 580                                inode->i_sb->s_id, function, line, inode->i_ino,
 581                                block, current->comm, path, &vaf);
 582                 else
 583                         printk(KERN_CRIT
 584                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 585                                "comm %s: path %s: %pV\n",
 586                                inode->i_sb->s_id, function, line, inode->i_ino,
 587                                current->comm, path, &vaf);
 588                 va_end(args);
 589         }
 590         save_error_info(inode->i_sb, function, line);
 591         ext4_handle_error(inode->i_sb);
 592 }
 593
 594 const char *ext4_decode_error(struct super_block *sb, int errno,
 595                               char nbuf[16])
 596 {
 597         char *errstr = NULL;
 598
 599         switch (errno) {
 600         case -EFSCORRUPTED:
 601                 errstr = "Corrupt filesystem";
 602                 break;
 603         case -EFSBADCRC:
 604                 errstr = "Filesystem failed CRC";
 605                 break;
 606         case -EIO:
 607                 errstr = "IO failure";
 608                 break;
 609         case -ENOMEM:
 610                 errstr = "Out of memory";
 611                 break;
 612         case -EROFS:
 613                 if (!sb || (EXT4_SB(sb)->s_journal &&
 614                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 615                         errstr = "Journal has aborted";
 616                 else
 617                         errstr = "Readonly filesystem";
 618                 break;
 619         default:
 620                 /* If the caller passed in an extra buffer for unknown
 621                  * errors, textualise them now.  Else we just return
 622                  * NULL. */
 623                 if (nbuf) {
 624                         /* Check for truncated error codes... */
 625                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 626                                 errstr = nbuf;
 627                 }
 628                 break;
 629         }
 630
 631         return errstr;
 632 }
 633
 634 /* __ext4_std_error decodes expected errors from journaling functions
 635  * automatically and invokes the appropriate error response.  */
 636
 637 void __ext4_std_error(struct super_block *sb, const char *function,
 638                       unsigned int line, int errno)
 639 {
 640         char nbuf[16];
 641         const char *errstr;
 642
 643         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 644                 return;
 645
 646         /* Special case: if the error is EROFS, and we're not already
 647          * inside a transaction, then there's really no point in logging
 648          * an error. */
 649         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 650                 return;
 651
 652         if (ext4_error_ratelimit(sb)) {
 653                 errstr = ext4_decode_error(sb, errno, nbuf);
 654                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 655                        sb->s_id, function, line, errstr);
 656         }
 657
 658         save_error_info(sb, function, line);
 659         ext4_handle_error(sb);
 660 }
 661
 662 /*
 663  * ext4_abort is a much stronger failure handler than ext4_error.  The
 664  * abort function may be used to deal with unrecoverable failures such
 665  * as journal IO errors or ENOMEM at a critical moment in log management.
 666  *
 667  * We unconditionally force the filesystem into an ABORT|READONLY state,
 668  * unless the error response on the fs has been set to panic in which
 669  * case we take the easy way out and panic immediately.
 670  */
 671
 672 void __ext4_abort(struct super_block *sb, const char *function,
 673                 unsigned int line, const char *fmt, ...)
 674 {
 675         struct va_format vaf;
 676         va_list args;
 677
 678         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 679                 return;
 680
 681         save_error_info(sb, function, line);
 682         va_start(args, fmt);
 683         vaf.fmt = fmt;
 684         vaf.va = &args;
 685         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 686                sb->s_id, function, line, &vaf);
 687         va_end(args);
 688
 689         if (sb_rdonly(sb) == 0) {
 690                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 691                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 692                 /*
 693                  * Make sure updated value of ->s_mount_flags will be visible
 694                  * before ->s_flags update
 695                  */
 696                 smp_wmb();
 697                 sb->s_flags |= SB_RDONLY;
 698                 if (EXT4_SB(sb)->s_journal)
 699                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 700                 save_error_info(sb, function, line);
 701         }
 702         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
 703                 if (EXT4_SB(sb)->s_journal &&
 704                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 705                         return;
 706                 panic("EXT4-fs panic from previous error\n");
 707         }
 708 }
 709
 710 void __ext4_msg(struct super_block *sb,
 711                 const char *prefix, const char *fmt, ...)
 712 {
 713         struct va_format vaf;
 714         va_list args;
 715
 716         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 717                 return;
 718
 719         va_start(args, fmt);
 720         vaf.fmt = fmt;
 721         vaf.va = &args;
 722         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 723         va_end(args);
 724 }
 725
 726 #define ext4_warning_ratelimit(sb)                                      \
 727                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 728                              "EXT4-fs warning")
 729
 730 void __ext4_warning(struct super_block *sb, const char *function,
 731                     unsigned int line, const char *fmt, ...)
 732 {
 733         struct va_format vaf;
 734         va_list args;
 735
 736         if (!ext4_warning_ratelimit(sb))
 737                 return;
 738
 739         va_start(args, fmt);
 740         vaf.fmt = fmt;
 741         vaf.va = &args;
 742         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 743                sb->s_id, function, line, &vaf);
 744         va_end(args);
 745 }
 746
 747 void __ext4_warning_inode(const struct inode *inode, const char *function,
 748                           unsigned int line, const char *fmt, ...)
 749 {
 750         struct va_format vaf;
 751         va_list args;
 752
 753         if (!ext4_warning_ratelimit(inode->i_sb))
 754                 return;
 755
 756         va_start(args, fmt);
 757         vaf.fmt = fmt;
 758         vaf.va = &args;
 759         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 760                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 761                function, line, inode->i_ino, current->comm, &vaf);
 762         va_end(args);
 763 }
 764
 765 void __ext4_grp_locked_error(const char *function, unsigned int line,
 766                              struct super_block *sb, ext4_group_t grp,
 767                              unsigned long ino, ext4_fsblk_t block,
 768                              const char *fmt, ...)
 769 __releases(bitlock)
 770 __acquires(bitlock)
 771 {
 772         struct va_format vaf;
 773         va_list args;
 774         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 775
 776         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 777                 return;
 778
 779         trace_ext4_error(sb, function, line);
 780         es->s_last_error_ino = cpu_to_le32(ino);
 781         es->s_last_error_block = cpu_to_le64(block);
 782         __save_error_info(sb, function, line);
 783
 784         if (ext4_error_ratelimit(sb)) {
 785                 va_start(args, fmt);
 786                 vaf.fmt = fmt;
 787                 vaf.va = &args;
 788                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 789                        sb->s_id, function, line, grp);
 790                 if (ino)
 791                         printk(KERN_CONT "inode %lu: ", ino);
 792                 if (block)
 793                         printk(KERN_CONT "block %llu:",
 794                                (unsigned long long) block);
 795                 printk(KERN_CONT "%pV\n", &vaf);
 796                 va_end(args);
 797         }
 798
 799         if (test_opt(sb, WARN_ON_ERROR))
 800                 WARN_ON_ONCE(1);
 801
 802         if (test_opt(sb, ERRORS_CONT)) {
 803                 ext4_commit_super(sb, 0);
 804                 return;
 805         }
 806
 807         ext4_unlock_group(sb, grp);
 808         ext4_commit_super(sb, 1);
 809         ext4_handle_error(sb);
 810         /*
 811          * We only get here in the ERRORS_RO case; relocking the group
 812          * may be dangerous, but nothing bad will happen since the
 813          * filesystem will have already been marked read/only and the
 814          * journal has been aborted.  We return 1 as a hint to callers
 815          * who might what to use the return value from
 816          * ext4_grp_locked_error() to distinguish between the
 817          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 818          * aggressively from the ext4 function in question, with a
 819          * more appropriate error code.
 820          */
 821         ext4_lock_group(sb, grp);
 822         return;
 823 }
 824
 825 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
 826                                      ext4_group_t group,
 827                                      unsigned int flags)
 828 {
 829         struct ext4_sb_info *sbi = EXT4_SB(sb);
 830         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
 831         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
 832         int ret;
 833
 834         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
 835                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
 836                                             &grp->bb_state);
 837                 if (!ret)
 838                         percpu_counter_sub(&sbi->s_freeclusters_counter,
 839                                            grp->bb_free);
 840         }
 841
 842         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
 843                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
 844                                             &grp->bb_state);
 845                 if (!ret && gdp) {
 846                         int count;
 847
 848                         count = ext4_free_inodes_count(sb, gdp);
 849                         percpu_counter_sub(&sbi->s_freeinodes_counter,
 850                                            count);
 851                 }
 852         }
 853 }
 854
 855 void ext4_update_dynamic_rev(struct super_block *sb)
 856 {
 857         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 858
 859         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 860                 return;
 861
 862         ext4_warning(sb,
 863                      "updating to rev %d because of new feature flag, "
 864                      "running e2fsck is recommended",
 865                      EXT4_DYNAMIC_REV);
 866
 867         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 868         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 869         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 870         /* leave es->s_feature_*compat flags alone */
 871         /* es->s_uuid will be set by e2fsck if empty */
 872
 873         /*
 874          * The rest of the superblock fields should be zero, and if not it
 875          * means they are likely already in use, so leave them alone.  We
 876          * can leave it up to e2fsck to clean up any inconsistencies there.
 877          */
 878 }
 879
 880 /*
 881  * Open the external journal device
 882  */
 883 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 884 {
 885         struct block_device *bdev;
 886         char b[BDEVNAME_SIZE];
 887
 888         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 889         if (IS_ERR(bdev))
 890                 goto fail;
 891         return bdev;
 892
 893 fail:
 894         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 895                         __bdevname(dev, b), PTR_ERR(bdev));
 896         return NULL;
 897 }
 898
 899 /*
 900  * Release the journal device
 901  */
 902 static void ext4_blkdev_put(struct block_device *bdev)
 903 {
 904         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 905 }
 906
 907 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 908 {
 909         struct block_device *bdev;
 910         bdev = sbi->journal_bdev;
 911         if (bdev) {
 912                 ext4_blkdev_put(bdev);
 913                 sbi->journal_bdev = NULL;
 914         }
 915 }
 916
 917 static inline struct inode *orphan_list_entry(struct list_head *l)
 918 {
 919         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 920 }
 921
 922 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 923 {
 924         struct list_head *l;
 925
 926         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 927                  le32_to_cpu(sbi->s_es->s_last_orphan));
 928
 929         printk(KERN_ERR "sb_info orphan list:\n");
 930         list_for_each(l, &sbi->s_orphan) {
 931                 struct inode *inode = orphan_list_entry(l);
 932                 printk(KERN_ERR "  "
 933                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 934                        inode->i_sb->s_id, inode->i_ino, inode,
 935                        inode->i_mode, inode->i_nlink,
 936                        NEXT_ORPHAN(inode));
 937         }
 938 }
 939
 940 #ifdef CONFIG_QUOTA
 941 static int ext4_quota_off(struct super_block *sb, int type);
 942
 943 static inline void ext4_quota_off_umount(struct super_block *sb)
 944 {
 945         int type;
 946
 947         /* Use our quota_off function to clear inode flags etc. */
 948         for (type = 0; type < EXT4_MAXQUOTAS; type++)
 949                 ext4_quota_off(sb, type);
 950 }
 951
 952 /*
 953  * This is a helper function which is used in the mount/remount
 954  * codepaths (which holds s_umount) to fetch the quota file name.
 955  */
 956 static inline char *get_qf_name(struct super_block *sb,
 957                                 struct ext4_sb_info *sbi,
 958                                 int type)
 959 {
 960         return rcu_dereference_protected(sbi->s_qf_names[type],
 961                                          lockdep_is_held(&sb->s_umount));
 962 }
 963 #else
 964 static inline void ext4_quota_off_umount(struct super_block *sb)
 965 {
 966 }
 967 #endif
 968
 969 static void ext4_put_super(struct super_block *sb)
 970 {
 971         struct ext4_sb_info *sbi = EXT4_SB(sb);
 972         struct ext4_super_block *es = sbi->s_es;
 973         int aborted = 0;
 974         int i, err;
 975
 976         ext4_unregister_li_request(sb);
 977         ext4_quota_off_umount(sb);
 978
 979         destroy_workqueue(sbi->rsv_conversion_wq);
 980
 981         if (sbi->s_journal) {
 982                 aborted = is_journal_aborted(sbi->s_journal);
 983                 err = jbd2_journal_destroy(sbi->s_journal);
 984                 sbi->s_journal = NULL;
 985                 if ((err < 0) && !aborted)
 986                         ext4_abort(sb, "Couldn't clean up the journal");
 987         }
 988
 989         ext4_unregister_sysfs(sb);
 990         ext4_es_unregister_shrinker(sbi);
 991         del_timer_sync(&sbi->s_err_report);
 992         ext4_release_system_zone(sb);
 993         ext4_mb_release(sb);
 994         ext4_ext_release(sb);
 995
 996         if (!sb_rdonly(sb) && !aborted) {
 997                 ext4_clear_feature_journal_needs_recovery(sb);
 998                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 999         }
1000         if (!sb_rdonly(sb))
1001                 ext4_commit_super(sb, 1);
1002
1003         for (i = 0; i < sbi->s_gdb_count; i++)
1004                 brelse(sbi->s_group_desc[i]);
1005         kvfree(sbi->s_group_desc);
1006         kvfree(sbi->s_flex_groups);
1007         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1008         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1009         percpu_counter_destroy(&sbi->s_dirs_counter);
1010         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1011         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
1012 #ifdef CONFIG_QUOTA
1013         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1014                 kfree(get_qf_name(sb, sbi, i));
1015 #endif
1016
1017         /* Debugging code just in case the in-memory inode orphan list
1018          * isn't empty.  The on-disk one can be non-empty if we've
1019          * detected an error and taken the fs readonly, but the
1020          * in-memory list had better be clean by this point. */
1021         if (!list_empty(&sbi->s_orphan))
1022                 dump_orphan_list(sb, sbi);
1023         J_ASSERT(list_empty(&sbi->s_orphan));
1024
1025         sync_blockdev(sb->s_bdev);
1026         invalidate_bdev(sb->s_bdev);
1027         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
1028                 /*
1029                  * Invalidate the journal device's buffers.  We don't want them
1030                  * floating about in memory - the physical journal device may
1031                  * hotswapped, and it breaks the `ro-after' testing code.
1032                  */
1033                 sync_blockdev(sbi->journal_bdev);
1034                 invalidate_bdev(sbi->journal_bdev);
1035                 ext4_blkdev_remove(sbi);
1036         }
1037
1038         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1039         sbi->s_ea_inode_cache = NULL;
1040
1041         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1042         sbi->s_ea_block_cache = NULL;
1043
1044         if (sbi->s_mmp_tsk)
1045                 kthread_stop(sbi->s_mmp_tsk);
1046         brelse(sbi->s_sbh);
1047         sb->s_fs_info = NULL;
1048         /*
1049          * Now that we are completely done shutting down the
1050          * superblock, we need to actually destroy the kobject.
1051          */
1052         kobject_put(&sbi->s_kobj);
1053         wait_for_completion(&sbi->s_kobj_unregister);
1054         if (sbi->s_chksum_driver)
1055                 crypto_free_shash(sbi->s_chksum_driver);
1056         kfree(sbi->s_blockgroup_lock);
1057         fs_put_dax(sbi->s_daxdev);
1058 #ifdef CONFIG_UNICODE
1059         utf8_unload(sbi->s_encoding);
1060 #endif
1061         kfree(sbi);
1062 }
1063
1064 static struct kmem_cache *ext4_inode_cachep;
1065
1066 /*
1067  * Called inside transaction, so use GFP_NOFS
1068  */
1069 static struct inode *ext4_alloc_inode(struct super_block *sb)
1070 {
1071         struct ext4_inode_info *ei;
1072
1073         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1074         if (!ei)
1075                 return NULL;
1076
1077         inode_set_iversion(&ei->vfs_inode, 1);
1078         spin_lock_init(&ei->i_raw_lock);
1079         INIT_LIST_HEAD(&ei->i_prealloc_list);
1080         spin_lock_init(&ei->i_prealloc_lock);
1081         ext4_es_init_tree(&ei->i_es_tree);
1082         rwlock_init(&ei->i_es_lock);
1083         INIT_LIST_HEAD(&ei->i_es_list);
1084         ei->i_es_all_nr = 0;
1085         ei->i_es_shk_nr = 0;
1086         ei->i_es_shrink_lblk = 0;
1087         ei->i_reserved_data_blocks = 0;
1088         ei->i_da_metadata_calc_len = 0;
1089         ei->i_da_metadata_calc_last_lblock = 0;
1090         spin_lock_init(&(ei->i_block_reservation_lock));
1091         ext4_init_pending_tree(&ei->i_pending_tree);
1092 #ifdef CONFIG_QUOTA
1093         ei->i_reserved_quota = 0;
1094         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1095 #endif
1096         ei->jinode = NULL;
1097         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1098         spin_lock_init(&ei->i_completed_io_lock);
1099         ei->i_sync_tid = 0;
1100         ei->i_datasync_tid = 0;
1101         atomic_set(&ei->i_unwritten, 0);
1102         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1103         return &ei->vfs_inode;
1104 }
1105
1106 static int ext4_drop_inode(struct inode *inode)
1107 {
1108         int drop = generic_drop_inode(inode);
1109
1110         if (!drop)
1111                 drop = fscrypt_drop_inode(inode);
1112
1113         trace_ext4_drop_inode(inode, drop);
1114         return drop;
1115 }
1116
1117 static void ext4_free_in_core_inode(struct inode *inode)
1118 {
1119         fscrypt_free_inode(inode);
1120         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1121 }
1122
1123 static void ext4_destroy_inode(struct inode *inode)
1124 {
1125         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1126                 ext4_msg(inode->i_sb, KERN_ERR,
1127                          "Inode %lu (%p): orphan list check failed!",
1128                          inode->i_ino, EXT4_I(inode));
1129                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1130                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1131                                 true);
1132                 dump_stack();
1133         }
1134 }
1135
1136 static void init_once(void *foo)
1137 {
1138         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1139
1140         INIT_LIST_HEAD(&ei->i_orphan);
1141         init_rwsem(&ei->xattr_sem);
1142         init_rwsem(&ei->i_data_sem);
1143         init_rwsem(&ei->i_mmap_sem);
1144         inode_init_once(&ei->vfs_inode);
1145 }
1146
1147 static int __init init_inodecache(void)
1148 {
1149         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1150                                 sizeof(struct ext4_inode_info), 0,
1151                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1152                                         SLAB_ACCOUNT),
1153                                 offsetof(struct ext4_inode_info, i_data),
1154                                 sizeof_field(struct ext4_inode_info, i_data),
1155                                 init_once);
1156         if (ext4_inode_cachep == NULL)
1157                 return -ENOMEM;
1158         return 0;
1159 }
1160
1161 static void destroy_inodecache(void)
1162 {
1163         /*
1164          * Make sure all delayed rcu free inodes are flushed before we
1165          * destroy cache.
1166          */
1167         rcu_barrier();
1168         kmem_cache_destroy(ext4_inode_cachep);
1169 }
1170
1171 void ext4_clear_inode(struct inode *inode)
1172 {
1173         invalidate_inode_buffers(inode);
1174         clear_inode(inode);
1175         ext4_discard_preallocations(inode);
1176         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1177         dquot_drop(inode);
1178         if (EXT4_I(inode)->jinode) {
1179                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1180                                                EXT4_I(inode)->jinode);
1181                 jbd2_free_inode(EXT4_I(inode)->jinode);
1182                 EXT4_I(inode)->jinode = NULL;
1183         }
1184         fscrypt_put_encryption_info(inode);
1185         fsverity_cleanup_inode(inode);
1186 }
1187
1188 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1189                                         u64 ino, u32 generation)
1190 {
1191         struct inode *inode;
1192
1193         /*
1194          * Currently we don't know the generation for parent directory, so
1195          * a generation of 0 means "accept any"
1196          */
1197         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1198         if (IS_ERR(inode))
1199                 return ERR_CAST(inode);
1200         if (generation && inode->i_generation != generation) {
1201                 iput(inode);
1202                 return ERR_PTR(-ESTALE);
1203         }
1204
1205         return inode;
1206 }
1207
1208 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1209                                         int fh_len, int fh_type)
1210 {
1211         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1212                                     ext4_nfs_get_inode);
1213 }
1214
1215 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1216                                         int fh_len, int fh_type)
1217 {
1218         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1219                                     ext4_nfs_get_inode);
1220 }
1221
1222 static int ext4_nfs_commit_metadata(struct inode *inode)
1223 {
1224         struct writeback_control wbc = {
1225                 .sync_mode = WB_SYNC_ALL
1226         };
1227
1228         trace_ext4_nfs_commit_metadata(inode);
1229         return ext4_write_inode(inode, &wbc);
1230 }
1231
1232 /*
1233  * Try to release metadata pages (indirect blocks, directories) which are
1234  * mapped via the block device.  Since these pages could have journal heads
1235  * which would prevent try_to_free_buffers() from freeing them, we must use
1236  * jbd2 layer's try_to_free_buffers() function to release them.
1237  */
1238 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1239                                  gfp_t wait)
1240 {
1241         journal_t *journal = EXT4_SB(sb)->s_journal;
1242
1243         WARN_ON(PageChecked(page));
1244         if (!page_has_buffers(page))
1245                 return 0;
1246         if (journal)
1247                 return jbd2_journal_try_to_free_buffers(journal, page,
1248                                                 wait & ~__GFP_DIRECT_RECLAIM);
1249         return try_to_free_buffers(page);
1250 }
1251
1252 #ifdef CONFIG_FS_ENCRYPTION
1253 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1254 {
1255         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1256                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1257 }
1258
1259 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1260                                                         void *fs_data)
1261 {
1262         handle_t *handle = fs_data;
1263         int res, res2, credits, retries = 0;
1264
1265         /*
1266          * Encrypting the root directory is not allowed because e2fsck expects
1267          * lost+found to exist and be unencrypted, and encrypting the root
1268          * directory would imply encrypting the lost+found directory as well as
1269          * the filename "lost+found" itself.
1270          */
1271         if (inode->i_ino == EXT4_ROOT_INO)
1272                 return -EPERM;
1273
1274         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1275                 return -EINVAL;
1276
1277         res = ext4_convert_inline_data(inode);
1278         if (res)
1279                 return res;
1280
1281         /*
1282          * If a journal handle was specified, then the encryption context is
1283          * being set on a new inode via inheritance and is part of a larger
1284          * transaction to create the inode.  Otherwise the encryption context is
1285          * being set on an existing inode in its own transaction.  Only in the
1286          * latter case should the "retry on ENOSPC" logic be used.
1287          */
1288
1289         if (handle) {
1290                 res = ext4_xattr_set_handle(handle, inode,
1291                                             EXT4_XATTR_INDEX_ENCRYPTION,
1292                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1293                                             ctx, len, 0);
1294                 if (!res) {
1295                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1296                         ext4_clear_inode_state(inode,
1297                                         EXT4_STATE_MAY_INLINE_DATA);
1298                         /*
1299                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1300                          * S_DAX may be disabled
1301                          */
1302                         ext4_set_inode_flags(inode);
1303                 }
1304                 return res;
1305         }
1306
1307         res = dquot_initialize(inode);
1308         if (res)
1309                 return res;
1310 retry:
1311         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1312                                      &credits);
1313         if (res)
1314                 return res;
1315
1316         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1317         if (IS_ERR(handle))
1318                 return PTR_ERR(handle);
1319
1320         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1321                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1322                                     ctx, len, 0);
1323         if (!res) {
1324                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1325                 /*
1326                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1327                  * S_DAX may be disabled
1328                  */
1329                 ext4_set_inode_flags(inode);
1330                 res = ext4_mark_inode_dirty(handle, inode);
1331                 if (res)
1332                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1333         }
1334         res2 = ext4_journal_stop(handle);
1335
1336         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1337                 goto retry;
1338         if (!res)
1339                 res = res2;
1340         return res;
1341 }
1342
1343 static bool ext4_dummy_context(struct inode *inode)
1344 {
1345         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1346 }
1347
1348 static bool ext4_has_stable_inodes(struct super_block *sb)
1349 {
1350         return ext4_has_feature_stable_inodes(sb);
1351 }
1352
1353 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1354                                        int *ino_bits_ret, int *lblk_bits_ret)
1355 {
1356         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1357         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1358 }
1359
1360 static const struct fscrypt_operations ext4_cryptops = {
1361         .key_prefix             = "ext4:",
1362         .get_context            = ext4_get_context,
1363         .set_context            = ext4_set_context,
1364         .dummy_context          = ext4_dummy_context,
1365         .empty_dir              = ext4_empty_dir,
1366         .max_namelen            = EXT4_NAME_LEN,
1367         .has_stable_inodes      = ext4_has_stable_inodes,
1368         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1369 };
1370 #endif
1371
1372 #ifdef CONFIG_QUOTA
1373 static const char * const quotatypes[] = INITQFNAMES;
1374 #define QTYPE2NAME(t) (quotatypes[t])
1375
1376 static int ext4_write_dquot(struct dquot *dquot);
1377 static int ext4_acquire_dquot(struct dquot *dquot);
1378 static int ext4_release_dquot(struct dquot *dquot);
1379 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1380 static int ext4_write_info(struct super_block *sb, int type);
1381 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1382                          const struct path *path);
1383 static int ext4_quota_on_mount(struct super_block *sb, int type);
1384 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1385                                size_t len, loff_t off);
1386 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1387                                 const char *data, size_t len, loff_t off);
1388 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1389                              unsigned int flags);
1390 static int ext4_enable_quotas(struct super_block *sb);
1391
1392 static struct dquot **ext4_get_dquots(struct inode *inode)
1393 {
1394         return EXT4_I(inode)->i_dquot;
1395 }
1396
1397 static const struct dquot_operations ext4_quota_operations = {
1398         .get_reserved_space     = ext4_get_reserved_space,
1399         .write_dquot            = ext4_write_dquot,
1400         .acquire_dquot          = ext4_acquire_dquot,
1401         .release_dquot          = ext4_release_dquot,
1402         .mark_dirty             = ext4_mark_dquot_dirty,
1403         .write_info             = ext4_write_info,
1404         .alloc_dquot            = dquot_alloc,
1405         .destroy_dquot          = dquot_destroy,
1406         .get_projid             = ext4_get_projid,
1407         .get_inode_usage        = ext4_get_inode_usage,
1408         .get_next_id            = dquot_get_next_id,
1409 };
1410
1411 static const struct quotactl_ops ext4_qctl_operations = {
1412         .quota_on       = ext4_quota_on,
1413         .quota_off      = ext4_quota_off,
1414         .quota_sync     = dquot_quota_sync,
1415         .get_state      = dquot_get_state,
1416         .set_info       = dquot_set_dqinfo,
1417         .get_dqblk      = dquot_get_dqblk,
1418         .set_dqblk      = dquot_set_dqblk,
1419         .get_nextdqblk  = dquot_get_next_dqblk,
1420 };
1421 #endif
1422
1423 static const struct super_operations ext4_sops = {
1424         .alloc_inode    = ext4_alloc_inode,
1425         .free_inode     = ext4_free_in_core_inode,
1426         .destroy_inode  = ext4_destroy_inode,
1427         .write_inode    = ext4_write_inode,
1428         .dirty_inode    = ext4_dirty_inode,
1429         .drop_inode     = ext4_drop_inode,
1430         .evict_inode    = ext4_evict_inode,
1431         .put_super      = ext4_put_super,
1432         .sync_fs        = ext4_sync_fs,
1433         .freeze_fs      = ext4_freeze,
1434         .unfreeze_fs    = ext4_unfreeze,
1435         .statfs         = ext4_statfs,
1436         .remount_fs     = ext4_remount,
1437         .show_options   = ext4_show_options,
1438 #ifdef CONFIG_QUOTA
1439         .quota_read     = ext4_quota_read,
1440         .quota_write    = ext4_quota_write,
1441         .get_dquots     = ext4_get_dquots,
1442 #endif
1443         .bdev_try_to_free_page = bdev_try_to_free_page,
1444 };
1445
1446 static const struct export_operations ext4_export_ops = {
1447         .fh_to_dentry = ext4_fh_to_dentry,
1448         .fh_to_parent = ext4_fh_to_parent,
1449         .get_parent = ext4_get_parent,
1450         .commit_metadata = ext4_nfs_commit_metadata,
1451 };
1452
1453 enum {
1454         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1455         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1456         Opt_nouid32, Opt_debug, Opt_removed,
1457         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1458         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1459         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1460         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1461         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1462         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1463         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1464         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1465         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1466         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1467         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1468         Opt_nowarn_on_error, Opt_mblk_io_submit,
1469         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1470         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1471         Opt_inode_readahead_blks, Opt_journal_ioprio,
1472         Opt_dioread_nolock, Opt_dioread_lock,
1473         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1474         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1475 };
1476
1477 static const match_table_t tokens = {
1478         {Opt_bsd_df, "bsddf"},
1479         {Opt_minix_df, "minixdf"},
1480         {Opt_grpid, "grpid"},
1481         {Opt_grpid, "bsdgroups"},
1482         {Opt_nogrpid, "nogrpid"},
1483         {Opt_nogrpid, "sysvgroups"},
1484         {Opt_resgid, "resgid=%u"},
1485         {Opt_resuid, "resuid=%u"},
1486         {Opt_sb, "sb=%u"},
1487         {Opt_err_cont, "errors=continue"},
1488         {Opt_err_panic, "errors=panic"},
1489         {Opt_err_ro, "errors=remount-ro"},
1490         {Opt_nouid32, "nouid32"},
1491         {Opt_debug, "debug"},
1492         {Opt_removed, "oldalloc"},
1493         {Opt_removed, "orlov"},
1494         {Opt_user_xattr, "user_xattr"},
1495         {Opt_nouser_xattr, "nouser_xattr"},
1496         {Opt_acl, "acl"},
1497         {Opt_noacl, "noacl"},
1498         {Opt_noload, "norecovery"},
1499         {Opt_noload, "noload"},
1500         {Opt_removed, "nobh"},
1501         {Opt_removed, "bh"},
1502         {Opt_commit, "commit=%u"},
1503         {Opt_min_batch_time, "min_batch_time=%u"},
1504         {Opt_max_batch_time, "max_batch_time=%u"},
1505         {Opt_journal_dev, "journal_dev=%u"},
1506         {Opt_journal_path, "journal_path=%s"},
1507         {Opt_journal_checksum, "journal_checksum"},
1508         {Opt_nojournal_checksum, "nojournal_checksum"},
1509         {Opt_journal_async_commit, "journal_async_commit"},
1510         {Opt_abort, "abort"},
1511         {Opt_data_journal, "data=journal"},
1512         {Opt_data_ordered, "data=ordered"},
1513         {Opt_data_writeback, "data=writeback"},
1514         {Opt_data_err_abort, "data_err=abort"},
1515         {Opt_data_err_ignore, "data_err=ignore"},
1516         {Opt_offusrjquota, "usrjquota="},
1517         {Opt_usrjquota, "usrjquota=%s"},
1518         {Opt_offgrpjquota, "grpjquota="},
1519         {Opt_grpjquota, "grpjquota=%s"},
1520         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1521         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1522         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1523         {Opt_grpquota, "grpquota"},
1524         {Opt_noquota, "noquota"},
1525         {Opt_quota, "quota"},
1526         {Opt_usrquota, "usrquota"},
1527         {Opt_prjquota, "prjquota"},
1528         {Opt_barrier, "barrier=%u"},
1529         {Opt_barrier, "barrier"},
1530         {Opt_nobarrier, "nobarrier"},
1531         {Opt_i_version, "i_version"},
1532         {Opt_dax, "dax"},
1533         {Opt_stripe, "stripe=%u"},
1534         {Opt_delalloc, "delalloc"},
1535         {Opt_warn_on_error, "warn_on_error"},
1536         {Opt_nowarn_on_error, "nowarn_on_error"},
1537         {Opt_lazytime, "lazytime"},
1538         {Opt_nolazytime, "nolazytime"},
1539         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1540         {Opt_nodelalloc, "nodelalloc"},
1541         {Opt_removed, "mblk_io_submit"},
1542         {Opt_removed, "nomblk_io_submit"},
1543         {Opt_block_validity, "block_validity"},
1544         {Opt_noblock_validity, "noblock_validity"},
1545         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1546         {Opt_journal_ioprio, "journal_ioprio=%u"},
1547         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1548         {Opt_auto_da_alloc, "auto_da_alloc"},
1549         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1550         {Opt_dioread_nolock, "dioread_nolock"},
1551         {Opt_dioread_lock, "dioread_lock"},
1552         {Opt_discard, "discard"},
1553         {Opt_nodiscard, "nodiscard"},
1554         {Opt_init_itable, "init_itable=%u"},
1555         {Opt_init_itable, "init_itable"},
1556         {Opt_noinit_itable, "noinit_itable"},
1557         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1558         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1559         {Opt_nombcache, "nombcache"},
1560         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1561         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1562         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1563         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1564         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1565         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1566         {Opt_err, NULL},
1567 };
1568
1569 static ext4_fsblk_t get_sb_block(void **data)
1570 {
1571         ext4_fsblk_t    sb_block;
1572         char            *options = (char *) *data;
1573
1574         if (!options || strncmp(options, "sb=", 3) != 0)
1575                 return 1;       /* Default location */
1576
1577         options += 3;
1578         /* TODO: use simple_strtoll with >32bit ext4 */
1579         sb_block = simple_strtoul(options, &options, 0);
1580         if (*options && *options != ',') {
1581                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1582                        (char *) *data);
1583                 return 1;
1584         }
1585         if (*options == ',')
1586                 options++;
1587         *data = (void *) options;
1588
1589         return sb_block;
1590 }
1591
1592 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1593 static const char deprecated_msg[] =
1594         "Mount option \"%s\" will be removed by %s\n"
1595         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1596
1597 #ifdef CONFIG_QUOTA
1598 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1599 {
1600         struct ext4_sb_info *sbi = EXT4_SB(sb);
1601         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1602         int ret = -1;
1603
1604         if (sb_any_quota_loaded(sb) && !old_qname) {
1605                 ext4_msg(sb, KERN_ERR,
1606                         "Cannot change journaled "
1607                         "quota options when quota turned on");
1608                 return -1;
1609         }
1610         if (ext4_has_feature_quota(sb)) {
1611                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1612                          "ignored when QUOTA feature is enabled");
1613                 return 1;
1614         }
1615         qname = match_strdup(args);
1616         if (!qname) {
1617                 ext4_msg(sb, KERN_ERR,
1618                         "Not enough memory for storing quotafile name");
1619                 return -1;
1620         }
1621         if (old_qname) {
1622                 if (strcmp(old_qname, qname) == 0)
1623                         ret = 1;
1624                 else
1625                         ext4_msg(sb, KERN_ERR,
1626                                  "%s quota file already specified",
1627                                  QTYPE2NAME(qtype));
1628                 goto errout;
1629         }
1630         if (strchr(qname, '/')) {
1631                 ext4_msg(sb, KERN_ERR,
1632                         "quotafile must be on filesystem root");
1633                 goto errout;
1634         }
1635         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1636         set_opt(sb, QUOTA);
1637         return 1;
1638 errout:
1639         kfree(qname);
1640         return ret;
1641 }
1642
1643 static int clear_qf_name(struct super_block *sb, int qtype)
1644 {
1645
1646         struct ext4_sb_info *sbi = EXT4_SB(sb);
1647         char *old_qname = get_qf_name(sb, sbi, qtype);
1648
1649         if (sb_any_quota_loaded(sb) && old_qname) {
1650                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1651                         " when quota turned on");
1652                 return -1;
1653         }
1654         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1655         synchronize_rcu();
1656         kfree(old_qname);
1657         return 1;
1658 }
1659 #endif
1660
1661 #define MOPT_SET        0x0001
1662 #define MOPT_CLEAR      0x0002
1663 #define MOPT_NOSUPPORT  0x0004
1664 #define MOPT_EXPLICIT   0x0008
1665 #define MOPT_CLEAR_ERR  0x0010
1666 #define MOPT_GTE0       0x0020
1667 #ifdef CONFIG_QUOTA
1668 #define MOPT_Q          0
1669 #define MOPT_QFMT       0x0040
1670 #else
1671 #define MOPT_Q          MOPT_NOSUPPORT
1672 #define MOPT_QFMT       MOPT_NOSUPPORT
1673 #endif
1674 #define MOPT_DATAJ      0x0080
1675 #define MOPT_NO_EXT2    0x0100
1676 #define MOPT_NO_EXT3    0x0200
1677 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1678 #define MOPT_STRING     0x0400
1679
1680 static const struct mount_opts {
1681         int     token;
1682         int     mount_opt;
1683         int     flags;
1684 } ext4_mount_opts[] = {
1685         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1686         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1687         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1688         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1689         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1690         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1691         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1692          MOPT_EXT4_ONLY | MOPT_SET},
1693         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1694          MOPT_EXT4_ONLY | MOPT_CLEAR},
1695         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1696         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1697         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1698          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1699         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1700          MOPT_EXT4_ONLY | MOPT_CLEAR},
1701         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1702         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1703         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1704          MOPT_EXT4_ONLY | MOPT_CLEAR},
1705         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1706          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1707         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1708                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1709          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1710         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1711         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1712         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1713         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1714         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1715          MOPT_NO_EXT2},
1716         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1717          MOPT_NO_EXT2},
1718         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1719         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1720         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1721         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1722         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1723         {Opt_commit, 0, MOPT_GTE0},
1724         {Opt_max_batch_time, 0, MOPT_GTE0},
1725         {Opt_min_batch_time, 0, MOPT_GTE0},
1726         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1727         {Opt_init_itable, 0, MOPT_GTE0},
1728         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1729         {Opt_stripe, 0, MOPT_GTE0},
1730         {Opt_resuid, 0, MOPT_GTE0},
1731         {Opt_resgid, 0, MOPT_GTE0},
1732         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1733         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1734         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1735         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1736         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1737         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1738          MOPT_NO_EXT2 | MOPT_DATAJ},
1739         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1740         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1741 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1742         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1743         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1744 #else
1745         {Opt_acl, 0, MOPT_NOSUPPORT},
1746         {Opt_noacl, 0, MOPT_NOSUPPORT},
1747 #endif
1748         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1749         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1750         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1751         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1752         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1753                                                         MOPT_SET | MOPT_Q},
1754         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1755                                                         MOPT_SET | MOPT_Q},
1756         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1757                                                         MOPT_SET | MOPT_Q},
1758         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1759                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1760                                                         MOPT_CLEAR | MOPT_Q},
1761         {Opt_usrjquota, 0, MOPT_Q},
1762         {Opt_grpjquota, 0, MOPT_Q},
1763         {Opt_offusrjquota, 0, MOPT_Q},
1764         {Opt_offgrpjquota, 0, MOPT_Q},
1765         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1766         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1767         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1768         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1769         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1770         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1771         {Opt_err, 0, 0}
1772 };
1773
1774 #ifdef CONFIG_UNICODE
1775 static const struct ext4_sb_encodings {
1776         __u16 magic;
1777         char *name;
1778         char *version;
1779 } ext4_sb_encoding_map[] = {
1780         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
1781 };
1782
1783 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
1784                                  const struct ext4_sb_encodings **encoding,
1785                                  __u16 *flags)
1786 {
1787         __u16 magic = le16_to_cpu(es->s_encoding);
1788         int i;
1789
1790         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1791                 if (magic == ext4_sb_encoding_map[i].magic)
1792                         break;
1793
1794         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
1795                 return -EINVAL;
1796
1797         *encoding = &ext4_sb_encoding_map[i];
1798         *flags = le16_to_cpu(es->s_encoding_flags);
1799
1800         return 0;
1801 }
1802 #endif
1803
1804 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1805                             substring_t *args, unsigned long *journal_devnum,
1806                             unsigned int *journal_ioprio, int is_remount)
1807 {
1808         struct ext4_sb_info *sbi = EXT4_SB(sb);
1809         const struct mount_opts *m;
1810         kuid_t uid;
1811         kgid_t gid;
1812         int arg = 0;
1813
1814 #ifdef CONFIG_QUOTA
1815         if (token == Opt_usrjquota)
1816                 return set_qf_name(sb, USRQUOTA, &args[0]);
1817         else if (token == Opt_grpjquota)
1818                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1819         else if (token == Opt_offusrjquota)
1820                 return clear_qf_name(sb, USRQUOTA);
1821         else if (token == Opt_offgrpjquota)
1822                 return clear_qf_name(sb, GRPQUOTA);
1823 #endif
1824         switch (token) {
1825         case Opt_noacl:
1826         case Opt_nouser_xattr:
1827                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1828                 break;
1829         case Opt_sb:
1830                 return 1;       /* handled by get_sb_block() */
1831         case Opt_removed:
1832                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1833                 return 1;
1834         case Opt_abort:
1835                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1836                 return 1;
1837         case Opt_i_version:
1838                 sb->s_flags |= SB_I_VERSION;
1839                 return 1;
1840         case Opt_lazytime:
1841                 sb->s_flags |= SB_LAZYTIME;
1842                 return 1;
1843         case Opt_nolazytime:
1844                 sb->s_flags &= ~SB_LAZYTIME;
1845                 return 1;
1846         }
1847
1848         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1849                 if (token == m->token)
1850                         break;
1851
1852         if (m->token == Opt_err) {
1853                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1854                          "or missing value", opt);
1855                 return -1;
1856         }
1857
1858         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1859                 ext4_msg(sb, KERN_ERR,
1860                          "Mount option \"%s\" incompatible with ext2", opt);
1861                 return -1;
1862         }
1863         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1864                 ext4_msg(sb, KERN_ERR,
1865                          "Mount option \"%s\" incompatible with ext3", opt);
1866                 return -1;
1867         }
1868
1869         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1870                 return -1;
1871         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1872                 return -1;
1873         if (m->flags & MOPT_EXPLICIT) {
1874                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1875                         set_opt2(sb, EXPLICIT_DELALLOC);
1876                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1877                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1878                 } else
1879                         return -1;
1880         }
1881         if (m->flags & MOPT_CLEAR_ERR)
1882                 clear_opt(sb, ERRORS_MASK);
1883         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1884                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1885                          "options when quota turned on");
1886                 return -1;
1887         }
1888
1889         if (m->flags & MOPT_NOSUPPORT) {
1890                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1891         } else if (token == Opt_commit) {
1892                 if (arg == 0)
1893                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1894                 else if (arg > INT_MAX / HZ) {
1895                         ext4_msg(sb, KERN_ERR,
1896                                  "Invalid commit interval %d, "
1897                                  "must be smaller than %d",
1898                                  arg, INT_MAX / HZ);
1899                         return -1;
1900                 }
1901                 sbi->s_commit_interval = HZ * arg;
1902         } else if (token == Opt_debug_want_extra_isize) {
1903                 sbi->s_want_extra_isize = arg;
1904         } else if (token == Opt_max_batch_time) {
1905                 sbi->s_max_batch_time = arg;
1906         } else if (token == Opt_min_batch_time) {
1907                 sbi->s_min_batch_time = arg;
1908         } else if (token == Opt_inode_readahead_blks) {
1909                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1910                         ext4_msg(sb, KERN_ERR,
1911                                  "EXT4-fs: inode_readahead_blks must be "
1912                                  "0 or a power of 2 smaller than 2^31");
1913                         return -1;
1914                 }
1915                 sbi->s_inode_readahead_blks = arg;
1916         } else if (token == Opt_init_itable) {
1917                 set_opt(sb, INIT_INODE_TABLE);
1918                 if (!args->from)
1919                         arg = EXT4_DEF_LI_WAIT_MULT;
1920                 sbi->s_li_wait_mult = arg;
1921         } else if (token == Opt_max_dir_size_kb) {
1922                 sbi->s_max_dir_size_kb = arg;
1923         } else if (token == Opt_stripe) {
1924                 sbi->s_stripe = arg;
1925         } else if (token == Opt_resuid) {
1926                 uid = make_kuid(current_user_ns(), arg);
1927                 if (!uid_valid(uid)) {
1928                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1929                         return -1;
1930                 }
1931                 sbi->s_resuid = uid;
1932         } else if (token == Opt_resgid) {
1933                 gid = make_kgid(current_user_ns(), arg);
1934                 if (!gid_valid(gid)) {
1935                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1936                         return -1;
1937                 }
1938                 sbi->s_resgid = gid;
1939         } else if (token == Opt_journal_dev) {
1940                 if (is_remount) {
1941                         ext4_msg(sb, KERN_ERR,
1942                                  "Cannot specify journal on remount");
1943                         return -1;
1944                 }
1945                 *journal_devnum = arg;
1946         } else if (token == Opt_journal_path) {
1947                 char *journal_path;
1948                 struct inode *journal_inode;
1949                 struct path path;
1950                 int error;
1951
1952                 if (is_remount) {
1953                         ext4_msg(sb, KERN_ERR,
1954                                  "Cannot specify journal on remount");
1955                         return -1;
1956                 }
1957                 journal_path = match_strdup(&args[0]);
1958                 if (!journal_path) {
1959                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1960                                 "journal device string");
1961                         return -1;
1962                 }
1963
1964                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1965                 if (error) {
1966                         ext4_msg(sb, KERN_ERR, "error: could not find "
1967                                 "journal device path: error %d", error);
1968                         kfree(journal_path);
1969                         return -1;
1970                 }
1971
1972                 journal_inode = d_inode(path.dentry);
1973                 if (!S_ISBLK(journal_inode->i_mode)) {
1974                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1975                                 "is not a block device", journal_path);
1976                         path_put(&path);
1977                         kfree(journal_path);
1978                         return -1;
1979                 }
1980
1981                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1982                 path_put(&path);
1983                 kfree(journal_path);
1984         } else if (token == Opt_journal_ioprio) {
1985                 if (arg > 7) {
1986                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1987                                  " (must be 0-7)");
1988                         return -1;
1989                 }
1990                 *journal_ioprio =
1991                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1992         } else if (token == Opt_test_dummy_encryption) {
1993 #ifdef CONFIG_FS_ENCRYPTION
1994                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1995                 ext4_msg(sb, KERN_WARNING,
1996                          "Test dummy encryption mode enabled");
1997 #else
1998                 ext4_msg(sb, KERN_WARNING,
1999                          "Test dummy encryption mount option ignored");
2000 #endif
2001         } else if (m->flags & MOPT_DATAJ) {
2002                 if (is_remount) {
2003                         if (!sbi->s_journal)
2004                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2005                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2006                                 ext4_msg(sb, KERN_ERR,
2007                                          "Cannot change data mode on remount");
2008                                 return -1;
2009                         }
2010                 } else {
2011                         clear_opt(sb, DATA_FLAGS);
2012                         sbi->s_mount_opt |= m->mount_opt;
2013                 }
2014 #ifdef CONFIG_QUOTA
2015         } else if (m->flags & MOPT_QFMT) {
2016                 if (sb_any_quota_loaded(sb) &&
2017                     sbi->s_jquota_fmt != m->mount_opt) {
2018                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2019                                  "quota options when quota turned on");
2020                         return -1;
2021                 }
2022                 if (ext4_has_feature_quota(sb)) {
2023                         ext4_msg(sb, KERN_INFO,
2024                                  "Quota format mount options ignored "
2025                                  "when QUOTA feature is enabled");
2026                         return 1;
2027                 }
2028                 sbi->s_jquota_fmt = m->mount_opt;
2029 #endif
2030         } else if (token == Opt_dax) {
2031 #ifdef CONFIG_FS_DAX
2032                 ext4_msg(sb, KERN_WARNING,
2033                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2034                 sbi->s_mount_opt |= m->mount_opt;
2035 #else
2036                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2037                 return -1;
2038 #endif
2039         } else if (token == Opt_data_err_abort) {
2040                 sbi->s_mount_opt |= m->mount_opt;
2041         } else if (token == Opt_data_err_ignore) {
2042                 sbi->s_mount_opt &= ~m->mount_opt;
2043         } else {
2044                 if (!args->from)
2045                         arg = 1;
2046                 if (m->flags & MOPT_CLEAR)
2047                         arg = !arg;
2048                 else if (unlikely(!(m->flags & MOPT_SET))) {
2049                         ext4_msg(sb, KERN_WARNING,
2050                                  "buggy handling of option %s", opt);
2051                         WARN_ON(1);
2052                         return -1;
2053                 }
2054                 if (arg != 0)
2055                         sbi->s_mount_opt |= m->mount_opt;
2056                 else
2057                         sbi->s_mount_opt &= ~m->mount_opt;
2058         }
2059         return 1;
2060 }
2061
2062 static int parse_options(char *options, struct super_block *sb,
2063                          unsigned long *journal_devnum,
2064                          unsigned int *journal_ioprio,
2065                          int is_remount)
2066 {
2067         struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2068         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2069         substring_t args[MAX_OPT_ARGS];
2070         int token;
2071
2072         if (!options)
2073                 return 1;
2074
2075         while ((p = strsep(&options, ",")) != NULL) {
2076                 if (!*p)
2077                         continue;
2078                 /*
2079                  * Initialize args struct so we know whether arg was
2080                  * found; some options take optional arguments.
2081                  */
2082                 args[0].to = args[0].from = NULL;
2083                 token = match_token(p, tokens, args);
2084                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2085                                      journal_ioprio, is_remount) < 0)
2086                         return 0;
2087         }
2088 #ifdef CONFIG_QUOTA
2089         /*
2090          * We do the test below only for project quotas. 'usrquota' and
2091          * 'grpquota' mount options are allowed even without quota feature
2092          * to support legacy quotas in quota files.
2093          */
2094         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2095                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2096                          "Cannot enable project quota enforcement.");
2097                 return 0;
2098         }
2099         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2100         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2101         if (usr_qf_name || grp_qf_name) {
2102                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2103                         clear_opt(sb, USRQUOTA);
2104
2105                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2106                         clear_opt(sb, GRPQUOTA);
2107
2108                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2109                         ext4_msg(sb, KERN_ERR, "old and new quota "
2110                                         "format mixing");
2111                         return 0;
2112                 }
2113
2114                 if (!sbi->s_jquota_fmt) {
2115                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2116                                         "not specified");
2117                         return 0;
2118                 }
2119         }
2120 #endif
2121         return 1;
2122 }
2123
2124 static inline void ext4_show_quota_options(struct seq_file *seq,
2125                                            struct super_block *sb)
2126 {
2127 #if defined(CONFIG_QUOTA)
2128         struct ext4_sb_info *sbi = EXT4_SB(sb);
2129         char *usr_qf_name, *grp_qf_name;
2130
2131         if (sbi->s_jquota_fmt) {
2132                 char *fmtname = "";
2133
2134                 switch (sbi->s_jquota_fmt) {
2135                 case QFMT_VFS_OLD:
2136                         fmtname = "vfsold";
2137                         break;
2138                 case QFMT_VFS_V0:
2139                         fmtname = "vfsv0";
2140                         break;
2141                 case QFMT_VFS_V1:
2142                         fmtname = "vfsv1";
2143                         break;
2144                 }
2145                 seq_printf(seq, ",jqfmt=%s", fmtname);
2146         }
2147
2148         rcu_read_lock();
2149         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2150         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2151         if (usr_qf_name)
2152                 seq_show_option(seq, "usrjquota", usr_qf_name);
2153         if (grp_qf_name)
2154                 seq_show_option(seq, "grpjquota", grp_qf_name);
2155         rcu_read_unlock();
2156 #endif
2157 }
2158
2159 static const char *token2str(int token)
2160 {
2161         const struct match_token *t;
2162
2163         for (t = tokens; t->token != Opt_err; t++)
2164                 if (t->token == token && !strchr(t->pattern, '='))
2165                         break;
2166         return t->pattern;
2167 }
2168
2169 /*
2170  * Show an option if
2171  *  - it's set to a non-default value OR
2172  *  - if the per-sb default is different from the global default
2173  */
2174 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2175                               int nodefs)
2176 {
2177         struct ext4_sb_info *sbi = EXT4_SB(sb);
2178         struct ext4_super_block *es = sbi->s_es;
2179         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2180         const struct mount_opts *m;
2181         char sep = nodefs ? '\n' : ',';
2182
2183 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2184 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2185
2186         if (sbi->s_sb_block != 1)
2187                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2188
2189         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2190                 int want_set = m->flags & MOPT_SET;
2191                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2192                     (m->flags & MOPT_CLEAR_ERR))
2193                         continue;
2194                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2195                         continue; /* skip if same as the default */
2196                 if ((want_set &&
2197                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2198                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2199                         continue; /* select Opt_noFoo vs Opt_Foo */
2200                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2201         }
2202
2203         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2204             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2205                 SEQ_OPTS_PRINT("resuid=%u",
2206                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2207         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2208             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2209                 SEQ_OPTS_PRINT("resgid=%u",
2210                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2211         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2212         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2213                 SEQ_OPTS_PUTS("errors=remount-ro");
2214         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2215                 SEQ_OPTS_PUTS("errors=continue");
2216         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2217                 SEQ_OPTS_PUTS("errors=panic");
2218         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2219                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2220         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2221                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2222         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2223                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2224         if (sb->s_flags & SB_I_VERSION)
2225                 SEQ_OPTS_PUTS("i_version");
2226         if (nodefs || sbi->s_stripe)
2227                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2228         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2229                         (sbi->s_mount_opt ^ def_mount_opt)) {
2230                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2231                         SEQ_OPTS_PUTS("data=journal");
2232                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2233                         SEQ_OPTS_PUTS("data=ordered");
2234                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2235                         SEQ_OPTS_PUTS("data=writeback");
2236         }
2237         if (nodefs ||
2238             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2239                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2240                                sbi->s_inode_readahead_blks);
2241
2242         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2243                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2244                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2245         if (nodefs || sbi->s_max_dir_size_kb)
2246                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2247         if (test_opt(sb, DATA_ERR_ABORT))
2248                 SEQ_OPTS_PUTS("data_err=abort");
2249         if (DUMMY_ENCRYPTION_ENABLED(sbi))
2250                 SEQ_OPTS_PUTS("test_dummy_encryption");
2251
2252         ext4_show_quota_options(seq, sb);
2253         return 0;
2254 }
2255
2256 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2257 {
2258         return _ext4_show_options(seq, root->d_sb, 0);
2259 }
2260
2261 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2262 {
2263         struct super_block *sb = seq->private;
2264         int rc;
2265
2266         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2267         rc = _ext4_show_options(seq, sb, 1);
2268         seq_puts(seq, "\n");
2269         return rc;
2270 }
2271
2272 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2273                             int read_only)
2274 {
2275         struct ext4_sb_info *sbi = EXT4_SB(sb);
2276         int err = 0;
2277
2278         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2279                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2280                          "forcing read-only mode");
2281                 err = -EROFS;
2282         }
2283         if (read_only)
2284                 goto done;
2285         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2286                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2287                          "running e2fsck is recommended");
2288         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2289                 ext4_msg(sb, KERN_WARNING,
2290                          "warning: mounting fs with errors, "
2291                          "running e2fsck is recommended");
2292         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2293                  le16_to_cpu(es->s_mnt_count) >=
2294                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2295                 ext4_msg(sb, KERN_WARNING,
2296                          "warning: maximal mount count reached, "
2297                          "running e2fsck is recommended");
2298         else if (le32_to_cpu(es->s_checkinterval) &&
2299                  (ext4_get_tstamp(es, s_lastcheck) +
2300                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2301                 ext4_msg(sb, KERN_WARNING,
2302                          "warning: checktime reached, "
2303                          "running e2fsck is recommended");
2304         if (!sbi->s_journal)
2305                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2306         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2307                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2308         le16_add_cpu(&es->s_mnt_count, 1);
2309         ext4_update_tstamp(es, s_mtime);
2310         if (sbi->s_journal)
2311                 ext4_set_feature_journal_needs_recovery(sb);
2312
2313         err = ext4_commit_super(sb, 1);
2314 done:
2315         if (test_opt(sb, DEBUG))
2316                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2317                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2318                         sb->s_blocksize,
2319                         sbi->s_groups_count,
2320                         EXT4_BLOCKS_PER_GROUP(sb),
2321                         EXT4_INODES_PER_GROUP(sb),
2322                         sbi->s_mount_opt, sbi->s_mount_opt2);
2323
2324         cleancache_init_fs(sb);
2325         return err;
2326 }
2327
2328 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2329 {
2330         struct ext4_sb_info *sbi = EXT4_SB(sb);
2331         struct flex_groups *new_groups;
2332         int size;
2333
2334         if (!sbi->s_log_groups_per_flex)
2335                 return 0;
2336
2337         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2338         if (size <= sbi->s_flex_groups_allocated)
2339                 return 0;
2340
2341         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
2342         new_groups = kvzalloc(size, GFP_KERNEL);
2343         if (!new_groups) {
2344                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
2345                          size / (int) sizeof(struct flex_groups));
2346                 return -ENOMEM;
2347         }
2348
2349         if (sbi->s_flex_groups) {
2350                 memcpy(new_groups, sbi->s_flex_groups,
2351                        (sbi->s_flex_groups_allocated *
2352                         sizeof(struct flex_groups)));
2353                 kvfree(sbi->s_flex_groups);
2354         }
2355         sbi->s_flex_groups = new_groups;
2356         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
2357         return 0;
2358 }
2359
2360 static int ext4_fill_flex_info(struct super_block *sb)
2361 {
2362         struct ext4_sb_info *sbi = EXT4_SB(sb);
2363         struct ext4_group_desc *gdp = NULL;
2364         ext4_group_t flex_group;
2365         int i, err;
2366
2367         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2368         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2369                 sbi->s_log_groups_per_flex = 0;
2370                 return 1;
2371         }
2372
2373         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2374         if (err)
2375                 goto failed;
2376
2377         for (i = 0; i < sbi->s_groups_count; i++) {
2378                 gdp = ext4_get_group_desc(sb, i, NULL);
2379
2380                 flex_group = ext4_flex_group(sbi, i);
2381                 atomic_add(ext4_free_inodes_count(sb, gdp),
2382                            &sbi->s_flex_groups[flex_group].free_inodes);
2383                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2384                              &sbi->s_flex_groups[flex_group].free_clusters);
2385                 atomic_add(ext4_used_dirs_count(sb, gdp),
2386                            &sbi->s_flex_groups[flex_group].used_dirs);
2387         }
2388
2389         return 1;
2390 failed:
2391         return 0;
2392 }
2393
2394 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2395                                    struct ext4_group_desc *gdp)
2396 {
2397         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2398         __u16 crc = 0;
2399         __le32 le_group = cpu_to_le32(block_group);
2400         struct ext4_sb_info *sbi = EXT4_SB(sb);
2401
2402         if (ext4_has_metadata_csum(sbi->s_sb)) {
2403                 /* Use new metadata_csum algorithm */
2404                 __u32 csum32;
2405                 __u16 dummy_csum = 0;
2406
2407                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2408                                      sizeof(le_group));
2409                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2410                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2411                                      sizeof(dummy_csum));
2412                 offset += sizeof(dummy_csum);
2413                 if (offset < sbi->s_desc_size)
2414                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2415                                              sbi->s_desc_size - offset);
2416
2417                 crc = csum32 & 0xFFFF;
2418                 goto out;
2419         }
2420
2421         /* old crc16 code */
2422         if (!ext4_has_feature_gdt_csum(sb))
2423                 return 0;
2424
2425         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2426         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2427         crc = crc16(crc, (__u8 *)gdp, offset);
2428         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2429         /* for checksum of struct ext4_group_desc do the rest...*/
2430         if (ext4_has_feature_64bit(sb) &&
2431             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2432                 crc = crc16(crc, (__u8 *)gdp + offset,
2433                             le16_to_cpu(sbi->s_es->s_desc_size) -
2434                                 offset);
2435
2436 out:
2437         return cpu_to_le16(crc);
2438 }
2439
2440 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2441                                 struct ext4_group_desc *gdp)
2442 {
2443         if (ext4_has_group_desc_csum(sb) &&
2444             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2445                 return 0;
2446
2447         return 1;
2448 }
2449
2450 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2451                               struct ext4_group_desc *gdp)
2452 {
2453         if (!ext4_has_group_desc_csum(sb))
2454                 return;
2455         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2456 }
2457
2458 /* Called at mount-time, super-block is locked */
2459 static int ext4_check_descriptors(struct super_block *sb,
2460                                   ext4_fsblk_t sb_block,
2461                                   ext4_group_t *first_not_zeroed)
2462 {
2463         struct ext4_sb_info *sbi = EXT4_SB(sb);
2464         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2465         ext4_fsblk_t last_block;
2466         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2467         ext4_fsblk_t block_bitmap;
2468         ext4_fsblk_t inode_bitmap;
2469         ext4_fsblk_t inode_table;
2470         int flexbg_flag = 0;
2471         ext4_group_t i, grp = sbi->s_groups_count;
2472
2473         if (ext4_has_feature_flex_bg(sb))
2474                 flexbg_flag = 1;
2475
2476         ext4_debug("Checking group descriptors");
2477
2478         for (i = 0; i < sbi->s_groups_count; i++) {
2479                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2480
2481                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2482                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2483                 else
2484                         last_block = first_block +
2485                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2486
2487                 if ((grp == sbi->s_groups_count) &&
2488                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2489                         grp = i;
2490
2491                 block_bitmap = ext4_block_bitmap(sb, gdp);
2492                 if (block_bitmap == sb_block) {
2493                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2494                                  "Block bitmap for group %u overlaps "
2495                                  "superblock", i);
2496                         if (!sb_rdonly(sb))
2497                                 return 0;
2498                 }
2499                 if (block_bitmap >= sb_block + 1 &&
2500                     block_bitmap <= last_bg_block) {
2501                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2502                                  "Block bitmap for group %u overlaps "
2503                                  "block group descriptors", i);
2504                         if (!sb_rdonly(sb))
2505                                 return 0;
2506                 }
2507                 if (block_bitmap < first_block || block_bitmap > last_block) {
2508                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2509                                "Block bitmap for group %u not in group "
2510                                "(block %llu)!", i, block_bitmap);
2511                         return 0;
2512                 }
2513                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2514                 if (inode_bitmap == sb_block) {
2515                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2516                                  "Inode bitmap for group %u overlaps "
2517                                  "superblock", i);
2518                         if (!sb_rdonly(sb))
2519                                 return 0;
2520                 }
2521                 if (inode_bitmap >= sb_block + 1 &&
2522                     inode_bitmap <= last_bg_block) {
2523                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2524                                  "Inode bitmap for group %u overlaps "
2525                                  "block group descriptors", i);
2526                         if (!sb_rdonly(sb))
2527                                 return 0;
2528                 }
2529                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2530                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2531                                "Inode bitmap for group %u not in group "
2532                                "(block %llu)!", i, inode_bitmap);
2533                         return 0;
2534                 }
2535                 inode_table = ext4_inode_table(sb, gdp);
2536                 if (inode_table == sb_block) {
2537                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2538                                  "Inode table for group %u overlaps "
2539                                  "superblock", i);
2540                         if (!sb_rdonly(sb))
2541                                 return 0;
2542                 }
2543                 if (inode_table >= sb_block + 1 &&
2544                     inode_table <= last_bg_block) {
2545                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2546                                  "Inode table for group %u overlaps "
2547                                  "block group descriptors", i);
2548                         if (!sb_rdonly(sb))
2549                                 return 0;
2550                 }
2551                 if (inode_table < first_block ||
2552                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2553                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2554                                "Inode table for group %u not in group "
2555                                "(block %llu)!", i, inode_table);
2556                         return 0;
2557                 }
2558                 ext4_lock_group(sb, i);
2559                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2560                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2561                                  "Checksum for group %u failed (%u!=%u)",
2562                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2563                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2564                         if (!sb_rdonly(sb)) {
2565                                 ext4_unlock_group(sb, i);
2566                                 return 0;
2567                         }
2568                 }
2569                 ext4_unlock_group(sb, i);
2570                 if (!flexbg_flag)
2571                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2572         }
2573         if (NULL != first_not_zeroed)
2574                 *first_not_zeroed = grp;
2575         return 1;
2576 }
2577
2578 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2579  * the superblock) which were deleted from all directories, but held open by
2580  * a process at the time of a crash.  We walk the list and try to delete these
2581  * inodes at recovery time (only with a read-write filesystem).
2582  *
2583  * In order to keep the orphan inode chain consistent during traversal (in
2584  * case of crash during recovery), we link each inode into the superblock
2585  * orphan list_head and handle it the same way as an inode deletion during
2586  * normal operation (which journals the operations for us).
2587  *
2588  * We only do an iget() and an iput() on each inode, which is very safe if we
2589  * accidentally point at an in-use or already deleted inode.  The worst that
2590  * can happen in this case is that we get a "bit already cleared" message from
2591  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2592  * e2fsck was run on this filesystem, and it must have already done the orphan
2593  * inode cleanup for us, so we can safely abort without any further action.
2594  */
2595 static void ext4_orphan_cleanup(struct super_block *sb,
2596                                 struct ext4_super_block *es)
2597 {
2598         unsigned int s_flags = sb->s_flags;
2599         int ret, nr_orphans = 0, nr_truncates = 0;
2600 #ifdef CONFIG_QUOTA
2601         int quota_update = 0;
2602         int i;
2603 #endif
2604         if (!es->s_last_orphan) {
2605                 jbd_debug(4, "no orphan inodes to clean up\n");
2606                 return;
2607         }
2608
2609         if (bdev_read_only(sb->s_bdev)) {
2610                 ext4_msg(sb, KERN_ERR, "write access "
2611                         "unavailable, skipping orphan cleanup");
2612                 return;
2613         }
2614
2615         /* Check if feature set would not allow a r/w mount */
2616         if (!ext4_feature_set_ok(sb, 0)) {
2617                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2618                          "unknown ROCOMPAT features");
2619                 return;
2620         }
2621
2622         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2623                 /* don't clear list on RO mount w/ errors */
2624                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2625                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2626                                   "clearing orphan list.\n");
2627                         es->s_last_orphan = 0;
2628                 }
2629                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2630                 return;
2631         }
2632
2633         if (s_flags & SB_RDONLY) {
2634                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2635                 sb->s_flags &= ~SB_RDONLY;
2636         }
2637 #ifdef CONFIG_QUOTA
2638         /* Needed for iput() to work correctly and not trash data */
2639         sb->s_flags |= SB_ACTIVE;
2640
2641         /*
2642          * Turn on quotas which were not enabled for read-only mounts if
2643          * filesystem has quota feature, so that they are updated correctly.
2644          */
2645         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2646                 int ret = ext4_enable_quotas(sb);
2647
2648                 if (!ret)
2649                         quota_update = 1;
2650                 else
2651                         ext4_msg(sb, KERN_ERR,
2652                                 "Cannot turn on quotas: error %d", ret);
2653         }
2654
2655         /* Turn on journaled quotas used for old sytle */
2656         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2657                 if (EXT4_SB(sb)->s_qf_names[i]) {
2658                         int ret = ext4_quota_on_mount(sb, i);
2659
2660                         if (!ret)
2661                                 quota_update = 1;
2662                         else
2663                                 ext4_msg(sb, KERN_ERR,
2664                                         "Cannot turn on journaled "
2665                                         "quota: type %d: error %d", i, ret);
2666                 }
2667         }
2668 #endif
2669
2670         while (es->s_last_orphan) {
2671                 struct inode *inode;
2672
2673                 /*
2674                  * We may have encountered an error during cleanup; if
2675                  * so, skip the rest.
2676                  */
2677                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2678                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2679                         es->s_last_orphan = 0;
2680                         break;
2681                 }
2682
2683                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2684                 if (IS_ERR(inode)) {
2685                         es->s_last_orphan = 0;
2686                         break;
2687                 }
2688
2689                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2690                 dquot_initialize(inode);
2691                 if (inode->i_nlink) {
2692                         if (test_opt(sb, DEBUG))
2693                                 ext4_msg(sb, KERN_DEBUG,
2694                                         "%s: truncating inode %lu to %lld bytes",
2695                                         __func__, inode->i_ino, inode->i_size);
2696                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2697                                   inode->i_ino, inode->i_size);
2698                         inode_lock(inode);
2699                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2700                         ret = ext4_truncate(inode);
2701                         if (ret)
2702                                 ext4_std_error(inode->i_sb, ret);
2703                         inode_unlock(inode);
2704                         nr_truncates++;
2705                 } else {
2706                         if (test_opt(sb, DEBUG))
2707                                 ext4_msg(sb, KERN_DEBUG,
2708                                         "%s: deleting unreferenced inode %lu",
2709                                         __func__, inode->i_ino);
2710                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2711                                   inode->i_ino);
2712                         nr_orphans++;
2713                 }
2714                 iput(inode);  /* The delete magic happens here! */
2715         }
2716
2717 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2718
2719         if (nr_orphans)
2720                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2721                        PLURAL(nr_orphans));
2722         if (nr_truncates)
2723                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2724                        PLURAL(nr_truncates));
2725 #ifdef CONFIG_QUOTA
2726         /* Turn off quotas if they were enabled for orphan cleanup */
2727         if (quota_update) {
2728                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2729                         if (sb_dqopt(sb)->files[i])
2730                                 dquot_quota_off(sb, i);
2731                 }
2732         }
2733 #endif
2734         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2735 }
2736
2737 /*
2738  * Maximal extent format file size.
2739  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2740  * extent format containers, within a sector_t, and within i_blocks
2741  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2742  * so that won't be a limiting factor.
2743  *
2744  * However there is other limiting factor. We do store extents in the form
2745  * of starting block and length, hence the resulting length of the extent
2746  * covering maximum file size must fit into on-disk format containers as
2747  * well. Given that length is always by 1 unit bigger than max unit (because
2748  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2749  *
2750  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2751  */
2752 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2753 {
2754         loff_t res;
2755         loff_t upper_limit = MAX_LFS_FILESIZE;
2756
2757         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
2758
2759         if (!has_huge_files) {
2760                 upper_limit = (1LL << 32) - 1;
2761
2762                 /* total blocks in file system block size */
2763                 upper_limit >>= (blkbits - 9);
2764                 upper_limit <<= blkbits;
2765         }
2766
2767         /*
2768          * 32-bit extent-start container, ee_block. We lower the maxbytes
2769          * by one fs block, so ee_len can cover the extent of maximum file
2770          * size
2771          */
2772         res = (1LL << 32) - 1;
2773         res <<= blkbits;
2774
2775         /* Sanity check against vm- & vfs- imposed limits */
2776         if (res > upper_limit)
2777                 res = upper_limit;
2778
2779         return res;
2780 }
2781
2782 /*
2783  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2784  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2785  * We need to be 1 filesystem block less than the 2^48 sector limit.
2786  */
2787 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2788 {
2789         loff_t res = EXT4_NDIR_BLOCKS;
2790         int meta_blocks;
2791         loff_t upper_limit;
2792         /* This is calculated to be the largest file size for a dense, block
2793          * mapped file such that the file's total number of 512-byte sectors,
2794          * including data and all indirect blocks, does not exceed (2^48 - 1).
2795          *
2796          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2797          * number of 512-byte sectors of the file.
2798          */
2799
2800         if (!has_huge_files) {
2801                 /*
2802                  * !has_huge_files or implies that the inode i_block field
2803                  * represents total file blocks in 2^32 512-byte sectors ==
2804                  * size of vfs inode i_blocks * 8
2805                  */
2806                 upper_limit = (1LL << 32) - 1;
2807
2808                 /* total blocks in file system block size */
2809                 upper_limit >>= (bits - 9);
2810
2811         } else {
2812                 /*
2813                  * We use 48 bit ext4_inode i_blocks
2814                  * With EXT4_HUGE_FILE_FL set the i_blocks
2815                  * represent total number of blocks in
2816                  * file system block size
2817                  */
2818                 upper_limit = (1LL << 48) - 1;
2819
2820         }
2821
2822         /* indirect blocks */
2823         meta_blocks = 1;
2824         /* double indirect blocks */
2825         meta_blocks += 1 + (1LL << (bits-2));
2826         /* tripple indirect blocks */
2827         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2828
2829         upper_limit -= meta_blocks;
2830         upper_limit <<= bits;
2831
2832         res += 1LL << (bits-2);
2833         res += 1LL << (2*(bits-2));
2834         res += 1LL << (3*(bits-2));
2835         res <<= bits;
2836         if (res > upper_limit)
2837                 res = upper_limit;
2838
2839         if (res > MAX_LFS_FILESIZE)
2840                 res = MAX_LFS_FILESIZE;
2841
2842         return res;
2843 }
2844
2845 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2846                                    ext4_fsblk_t logical_sb_block, int nr)
2847 {
2848         struct ext4_sb_info *sbi = EXT4_SB(sb);
2849         ext4_group_t bg, first_meta_bg;
2850         int has_super = 0;
2851
2852         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2853
2854         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2855                 return logical_sb_block + nr + 1;
2856         bg = sbi->s_desc_per_block * nr;
2857         if (ext4_bg_has_super(sb, bg))
2858                 has_super = 1;
2859
2860         /*
2861          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2862          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2863          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2864          * compensate.
2865          */
2866         if (sb->s_blocksize == 1024 && nr == 0 &&
2867             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
2868                 has_super++;
2869
2870         return (has_super + ext4_group_first_block_no(sb, bg));
2871 }
2872
2873 /**
2874  * ext4_get_stripe_size: Get the stripe size.
2875  * @sbi: In memory super block info
2876  *
2877  * If we have specified it via mount option, then
2878  * use the mount option value. If the value specified at mount time is
2879  * greater than the blocks per group use the super block value.
2880  * If the super block value is greater than blocks per group return 0.
2881  * Allocator needs it be less than blocks per group.
2882  *
2883  */
2884 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2885 {
2886         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2887         unsigned long stripe_width =
2888                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2889         int ret;
2890
2891         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2892                 ret = sbi->s_stripe;
2893         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2894                 ret = stripe_width;
2895         else if (stride && stride <= sbi->s_blocks_per_group)
2896                 ret = stride;
2897         else
2898                 ret = 0;
2899
2900         /*
2901          * If the stripe width is 1, this makes no sense and
2902          * we set it to 0 to turn off stripe handling code.
2903          */
2904         if (ret <= 1)
2905                 ret = 0;
2906
2907         return ret;
2908 }
2909
2910 /*
2911  * Check whether this filesystem can be mounted based on
2912  * the features present and the RDONLY/RDWR mount requested.
2913  * Returns 1 if this filesystem can be mounted as requested,
2914  * 0 if it cannot be.
2915  */
2916 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2917 {
2918         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2919                 ext4_msg(sb, KERN_ERR,
2920                         "Couldn't mount because of "
2921                         "unsupported optional features (%x)",
2922                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2923                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2924                 return 0;
2925         }
2926
2927 #ifndef CONFIG_UNICODE
2928         if (ext4_has_feature_casefold(sb)) {
2929                 ext4_msg(sb, KERN_ERR,
2930                          "Filesystem with casefold feature cannot be "
2931                          "mounted without CONFIG_UNICODE");
2932                 return 0;
2933         }
2934 #endif
2935
2936         if (readonly)
2937                 return 1;
2938
2939         if (ext4_has_feature_readonly(sb)) {
2940                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2941                 sb->s_flags |= SB_RDONLY;
2942                 return 1;
2943         }
2944
2945         /* Check that feature set is OK for a read-write mount */
2946         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2947                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2948                          "unsupported optional features (%x)",
2949                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2950                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2951                 return 0;
2952         }
2953         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2954                 ext4_msg(sb, KERN_ERR,
2955                          "Can't support bigalloc feature without "
2956                          "extents feature\n");
2957                 return 0;
2958         }
2959
2960 #ifndef CONFIG_QUOTA
2961         if (ext4_has_feature_quota(sb) && !readonly) {
2962                 ext4_msg(sb, KERN_ERR,
2963                          "Filesystem with quota feature cannot be mounted RDWR "
2964                          "without CONFIG_QUOTA");
2965                 return 0;
2966         }
2967         if (ext4_has_feature_project(sb) && !readonly) {
2968                 ext4_msg(sb, KERN_ERR,
2969                          "Filesystem with project quota feature cannot be mounted RDWR "
2970                          "without CONFIG_QUOTA");
2971                 return 0;
2972         }
2973 #endif  /* CONFIG_QUOTA */
2974         return 1;
2975 }
2976
2977 /*
2978  * This function is called once a day if we have errors logged
2979  * on the file system
2980  */
2981 static void print_daily_error_info(struct timer_list *t)
2982 {
2983         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
2984         struct super_block *sb = sbi->s_sb;
2985         struct ext4_super_block *es = sbi->s_es;
2986
2987         if (es->s_error_count)
2988                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2989                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2990                          le32_to_cpu(es->s_error_count));
2991         if (es->s_first_error_time) {
2992                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
2993                        sb->s_id,
2994                        ext4_get_tstamp(es, s_first_error_time),
2995                        (int) sizeof(es->s_first_error_func),
2996                        es->s_first_error_func,
2997                        le32_to_cpu(es->s_first_error_line));
2998                 if (es->s_first_error_ino)
2999                         printk(KERN_CONT ": inode %u",
3000                                le32_to_cpu(es->s_first_error_ino));
3001                 if (es->s_first_error_block)
3002                         printk(KERN_CONT ": block %llu", (unsigned long long)
3003                                le64_to_cpu(es->s_first_error_block));
3004                 printk(KERN_CONT "\n");
3005         }
3006         if (es->s_last_error_time) {
3007                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3008                        sb->s_id,
3009                        ext4_get_tstamp(es, s_last_error_time),
3010                        (int) sizeof(es->s_last_error_func),
3011                        es->s_last_error_func,
3012                        le32_to_cpu(es->s_last_error_line));
3013                 if (es->s_last_error_ino)
3014                         printk(KERN_CONT ": inode %u",
3015                                le32_to_cpu(es->s_last_error_ino));
3016                 if (es->s_last_error_block)
3017                         printk(KERN_CONT ": block %llu", (unsigned long long)
3018                                le64_to_cpu(es->s_last_error_block));
3019                 printk(KERN_CONT "\n");
3020         }
3021         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3022 }
3023
3024 /* Find next suitable group and run ext4_init_inode_table */
3025 static int ext4_run_li_request(struct ext4_li_request *elr)
3026 {
3027         struct ext4_group_desc *gdp = NULL;
3028         ext4_group_t group, ngroups;
3029         struct super_block *sb;
3030         unsigned long timeout = 0;
3031         int ret = 0;
3032
3033         sb = elr->lr_super;
3034         ngroups = EXT4_SB(sb)->s_groups_count;
3035
3036         for (group = elr->lr_next_group; group < ngroups; group++) {
3037                 gdp = ext4_get_group_desc(sb, group, NULL);
3038                 if (!gdp) {
3039                         ret = 1;
3040                         break;
3041                 }
3042
3043                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3044                         break;
3045         }
3046
3047         if (group >= ngroups)
3048                 ret = 1;
3049
3050         if (!ret) {
3051                 timeout = jiffies;
3052                 ret = ext4_init_inode_table(sb, group,
3053                                             elr->lr_timeout ? 0 : 1);
3054                 if (elr->lr_timeout == 0) {
3055                         timeout = (jiffies - timeout) *
3056                                   elr->lr_sbi->s_li_wait_mult;
3057                         elr->lr_timeout = timeout;
3058                 }
3059                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3060                 elr->lr_next_group = group + 1;
3061         }
3062         return ret;
3063 }
3064
3065 /*
3066  * Remove lr_request from the list_request and free the
3067  * request structure. Should be called with li_list_mtx held
3068  */
3069 static void ext4_remove_li_request(struct ext4_li_request *elr)
3070 {
3071         struct ext4_sb_info *sbi;
3072
3073         if (!elr)
3074                 return;
3075
3076         sbi = elr->lr_sbi;
3077
3078         list_del(&elr->lr_request);
3079         sbi->s_li_request = NULL;
3080         kfree(elr);
3081 }
3082
3083 static void ext4_unregister_li_request(struct super_block *sb)
3084 {
3085         mutex_lock(&ext4_li_mtx);
3086         if (!ext4_li_info) {
3087                 mutex_unlock(&ext4_li_mtx);
3088                 return;
3089         }
3090
3091         mutex_lock(&ext4_li_info->li_list_mtx);
3092         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3093         mutex_unlock(&ext4_li_info->li_list_mtx);
3094         mutex_unlock(&ext4_li_mtx);
3095 }
3096
3097 static struct task_struct *ext4_lazyinit_task;
3098
3099 /*
3100  * This is the function where ext4lazyinit thread lives. It walks
3101  * through the request list searching for next scheduled filesystem.
3102  * When such a fs is found, run the lazy initialization request
3103  * (ext4_rn_li_request) and keep track of the time spend in this
3104  * function. Based on that time we compute next schedule time of
3105  * the request. When walking through the list is complete, compute
3106  * next waking time and put itself into sleep.
3107  */
3108 static int ext4_lazyinit_thread(void *arg)
3109 {
3110         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3111         struct list_head *pos, *n;
3112         struct ext4_li_request *elr;
3113         unsigned long next_wakeup, cur;
3114
3115         BUG_ON(NULL == eli);
3116
3117 cont_thread:
3118         while (true) {
3119                 next_wakeup = MAX_JIFFY_OFFSET;
3120
3121                 mutex_lock(&eli->li_list_mtx);
3122                 if (list_empty(&eli->li_request_list)) {
3123                         mutex_unlock(&eli->li_list_mtx);
3124                         goto exit_thread;
3125                 }
3126                 list_for_each_safe(pos, n, &eli->li_request_list) {
3127                         int err = 0;
3128                         int progress = 0;
3129                         elr = list_entry(pos, struct ext4_li_request,
3130                                          lr_request);
3131
3132                         if (time_before(jiffies, elr->lr_next_sched)) {
3133                                 if (time_before(elr->lr_next_sched, next_wakeup))
3134                                         next_wakeup = elr->lr_next_sched;
3135                                 continue;
3136                         }
3137                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3138                                 if (sb_start_write_trylock(elr->lr_super)) {
3139                                         progress = 1;
3140                                         /*
3141                                          * We hold sb->s_umount, sb can not
3142                                          * be removed from the list, it is
3143                                          * now safe to drop li_list_mtx
3144                                          */
3145                                         mutex_unlock(&eli->li_list_mtx);
3146                                         err = ext4_run_li_request(elr);
3147                                         sb_end_write(elr->lr_super);
3148                                         mutex_lock(&eli->li_list_mtx);
3149                                         n = pos->next;
3150                                 }
3151                                 up_read((&elr->lr_super->s_umount));
3152                         }
3153                         /* error, remove the lazy_init job */
3154                         if (err) {
3155                                 ext4_remove_li_request(elr);
3156                                 continue;
3157                         }
3158                         if (!progress) {
3159                                 elr->lr_next_sched = jiffies +
3160                                         (prandom_u32()
3161                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3162                         }
3163                         if (time_before(elr->lr_next_sched, next_wakeup))
3164                                 next_wakeup = elr->lr_next_sched;
3165                 }
3166                 mutex_unlock(&eli->li_list_mtx);
3167
3168                 try_to_freeze();
3169
3170                 cur = jiffies;
3171                 if ((time_after_eq(cur, next_wakeup)) ||
3172                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3173                         cond_resched();
3174                         continue;
3175                 }
3176
3177                 schedule_timeout_interruptible(next_wakeup - cur);
3178
3179                 if (kthread_should_stop()) {
3180                         ext4_clear_request_list();
3181                         goto exit_thread;
3182                 }
3183         }
3184
3185 exit_thread:
3186         /*
3187          * It looks like the request list is empty, but we need
3188          * to check it under the li_list_mtx lock, to prevent any
3189          * additions into it, and of course we should lock ext4_li_mtx
3190          * to atomically free the list and ext4_li_info, because at
3191          * this point another ext4 filesystem could be registering
3192          * new one.
3193          */
3194         mutex_lock(&ext4_li_mtx);
3195         mutex_lock(&eli->li_list_mtx);
3196         if (!list_empty(&eli->li_request_list)) {
3197                 mutex_unlock(&eli->li_list_mtx);
3198                 mutex_unlock(&ext4_li_mtx);
3199                 goto cont_thread;
3200         }
3201         mutex_unlock(&eli->li_list_mtx);
3202         kfree(ext4_li_info);
3203         ext4_li_info = NULL;
3204         mutex_unlock(&ext4_li_mtx);
3205
3206         return 0;
3207 }
3208
3209 static void ext4_clear_request_list(void)
3210 {
3211         struct list_head *pos, *n;
3212         struct ext4_li_request *elr;
3213
3214         mutex_lock(&ext4_li_info->li_list_mtx);
3215         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3216                 elr = list_entry(pos, struct ext4_li_request,
3217                                  lr_request);
3218                 ext4_remove_li_request(elr);
3219         }
3220         mutex_unlock(&ext4_li_info->li_list_mtx);
3221 }
3222
3223 static int ext4_run_lazyinit_thread(void)
3224 {
3225         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3226                                          ext4_li_info, "ext4lazyinit");
3227         if (IS_ERR(ext4_lazyinit_task)) {
3228                 int err = PTR_ERR(ext4_lazyinit_task);
3229                 ext4_clear_request_list();
3230                 kfree(ext4_li_info);
3231                 ext4_li_info = NULL;
3232                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3233                                  "initialization thread\n",
3234                                  err);
3235                 return err;
3236         }
3237         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3238         return 0;
3239 }
3240
3241 /*
3242  * Check whether it make sense to run itable init. thread or not.
3243  * If there is at least one uninitialized inode table, return
3244  * corresponding group number, else the loop goes through all
3245  * groups and return total number of groups.
3246  */
3247 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3248 {
3249         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3250         struct ext4_group_desc *gdp = NULL;
3251
3252         if (!ext4_has_group_desc_csum(sb))
3253                 return ngroups;
3254
3255         for (group = 0; group < ngroups; group++) {
3256                 gdp = ext4_get_group_desc(sb, group, NULL);
3257                 if (!gdp)
3258                         continue;
3259
3260                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3261                         break;
3262         }
3263
3264         return group;
3265 }
3266
3267 static int ext4_li_info_new(void)
3268 {
3269         struct ext4_lazy_init *eli = NULL;
3270
3271         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3272         if (!eli)
3273                 return -ENOMEM;
3274
3275         INIT_LIST_HEAD(&eli->li_request_list);
3276         mutex_init(&eli->li_list_mtx);
3277
3278         eli->li_state |= EXT4_LAZYINIT_QUIT;
3279
3280         ext4_li_info = eli;
3281
3282         return 0;
3283 }
3284
3285 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3286                                             ext4_group_t start)
3287 {
3288         struct ext4_sb_info *sbi = EXT4_SB(sb);
3289         struct ext4_li_request *elr;
3290
3291         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3292         if (!elr)
3293                 return NULL;
3294
3295         elr->lr_super = sb;
3296         elr->lr_sbi = sbi;
3297         elr->lr_next_group = start;
3298
3299         /*
3300          * Randomize first schedule time of the request to
3301          * spread the inode table initialization requests
3302          * better.
3303          */
3304         elr->lr_next_sched = jiffies + (prandom_u32() %
3305                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3306         return elr;
3307 }
3308
3309 int ext4_register_li_request(struct super_block *sb,
3310                              ext4_group_t first_not_zeroed)
3311 {
3312         struct ext4_sb_info *sbi = EXT4_SB(sb);
3313         struct ext4_li_request *elr = NULL;
3314         ext4_group_t ngroups = sbi->s_groups_count;
3315         int ret = 0;
3316
3317         mutex_lock(&ext4_li_mtx);
3318         if (sbi->s_li_request != NULL) {
3319                 /*
3320                  * Reset timeout so it can be computed again, because
3321                  * s_li_wait_mult might have changed.
3322                  */
3323                 sbi->s_li_request->lr_timeout = 0;
3324                 goto out;
3325         }
3326
3327         if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3328             !test_opt(sb, INIT_INODE_TABLE))
3329                 goto out;
3330
3331         elr = ext4_li_request_new(sb, first_not_zeroed);
3332         if (!elr) {
3333                 ret = -ENOMEM;
3334                 goto out;
3335         }
3336
3337         if (NULL == ext4_li_info) {
3338                 ret = ext4_li_info_new();
3339                 if (ret)
3340                         goto out;
3341         }
3342
3343         mutex_lock(&ext4_li_info->li_list_mtx);
3344         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3345         mutex_unlock(&ext4_li_info->li_list_mtx);
3346
3347         sbi->s_li_request = elr;
3348         /*
3349          * set elr to NULL here since it has been inserted to
3350          * the request_list and the removal and free of it is
3351          * handled by ext4_clear_request_list from now on.
3352          */
3353         elr = NULL;
3354
3355         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3356                 ret = ext4_run_lazyinit_thread();
3357                 if (ret)
3358                         goto out;
3359         }
3360 out:
3361         mutex_unlock(&ext4_li_mtx);
3362         if (ret)
3363                 kfree(elr);
3364         return ret;
3365 }
3366
3367 /*
3368  * We do not need to lock anything since this is called on
3369  * module unload.
3370  */
3371 static void ext4_destroy_lazyinit_thread(void)
3372 {
3373         /*
3374          * If thread exited earlier
3375          * there's nothing to be done.
3376          */
3377         if (!ext4_li_info || !ext4_lazyinit_task)
3378                 return;
3379
3380         kthread_stop(ext4_lazyinit_task);
3381 }
3382
3383 static int set_journal_csum_feature_set(struct super_block *sb)
3384 {
3385         int ret = 1;
3386         int compat, incompat;
3387         struct ext4_sb_info *sbi = EXT4_SB(sb);
3388
3389         if (ext4_has_metadata_csum(sb)) {
3390                 /* journal checksum v3 */
3391                 compat = 0;
3392                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3393         } else {
3394                 /* journal checksum v1 */
3395                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3396                 incompat = 0;
3397         }
3398
3399         jbd2_journal_clear_features(sbi->s_journal,
3400                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3401                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3402                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3403         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3404                 ret = jbd2_journal_set_features(sbi->s_journal,
3405                                 compat, 0,
3406                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3407                                 incompat);
3408         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3409                 ret = jbd2_journal_set_features(sbi->s_journal,
3410                                 compat, 0,
3411                                 incompat);
3412                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3413                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3414         } else {
3415                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3416                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3417         }
3418
3419         return ret;
3420 }
3421
3422 /*
3423  * Note: calculating the overhead so we can be compatible with
3424  * historical BSD practice is quite difficult in the face of
3425  * clusters/bigalloc.  This is because multiple metadata blocks from
3426  * different block group can end up in the same allocation cluster.
3427  * Calculating the exact overhead in the face of clustered allocation
3428  * requires either O(all block bitmaps) in memory or O(number of block
3429  * groups**2) in time.  We will still calculate the superblock for
3430  * older file systems --- and if we come across with a bigalloc file
3431  * system with zero in s_overhead_clusters the estimate will be close to
3432  * correct especially for very large cluster sizes --- but for newer
3433  * file systems, it's better to calculate this figure once at mkfs
3434  * time, and store it in the superblock.  If the superblock value is
3435  * present (even for non-bigalloc file systems), we will use it.
3436  */
3437 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3438                           char *buf)
3439 {
3440         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3441         struct ext4_group_desc  *gdp;
3442         ext4_fsblk_t            first_block, last_block, b;
3443         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3444         int                     s, j, count = 0;
3445
3446         if (!ext4_has_feature_bigalloc(sb))
3447                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3448                         sbi->s_itb_per_group + 2);
3449
3450         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3451                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3452         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3453         for (i = 0; i < ngroups; i++) {
3454                 gdp = ext4_get_group_desc(sb, i, NULL);
3455                 b = ext4_block_bitmap(sb, gdp);
3456                 if (b >= first_block && b <= last_block) {
3457                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3458                         count++;
3459                 }
3460                 b = ext4_inode_bitmap(sb, gdp);
3461                 if (b >= first_block && b <= last_block) {
3462                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3463                         count++;
3464                 }
3465                 b = ext4_inode_table(sb, gdp);
3466                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3467                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3468                                 int c = EXT4_B2C(sbi, b - first_block);
3469                                 ext4_set_bit(c, buf);
3470                                 count++;
3471                         }
3472                 if (i != grp)
3473                         continue;
3474                 s = 0;
3475                 if (ext4_bg_has_super(sb, grp)) {
3476                         ext4_set_bit(s++, buf);
3477                         count++;
3478                 }
3479                 j = ext4_bg_num_gdb(sb, grp);
3480                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3481                         ext4_error(sb, "Invalid number of block group "
3482                                    "descriptor blocks: %d", j);
3483                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3484                 }
3485                 count += j;
3486                 for (; j > 0; j--)
3487                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3488         }
3489         if (!count)
3490                 return 0;
3491         return EXT4_CLUSTERS_PER_GROUP(sb) -
3492                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3493 }
3494
3495 /*
3496  * Compute the overhead and stash it in sbi->s_overhead
3497  */
3498 int ext4_calculate_overhead(struct super_block *sb)
3499 {
3500         struct ext4_sb_info *sbi = EXT4_SB(sb);
3501         struct ext4_super_block *es = sbi->s_es;
3502         struct inode *j_inode;
3503         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3504         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3505         ext4_fsblk_t overhead = 0;
3506         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3507
3508         if (!buf)
3509                 return -ENOMEM;
3510
3511         /*
3512          * Compute the overhead (FS structures).  This is constant
3513          * for a given filesystem unless the number of block groups
3514          * changes so we cache the previous value until it does.
3515          */
3516
3517         /*
3518          * All of the blocks before first_data_block are overhead
3519          */
3520         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3521
3522         /*
3523          * Add the overhead found in each block group
3524          */
3525         for (i = 0; i < ngroups; i++) {
3526                 int blks;
3527
3528                 blks = count_overhead(sb, i, buf);
3529                 overhead += blks;
3530                 if (blks)
3531                         memset(buf, 0, PAGE_SIZE);
3532                 cond_resched();
3533         }
3534
3535         /*
3536          * Add the internal journal blocks whether the journal has been
3537          * loaded or not
3538          */
3539         if (sbi->s_journal && !sbi->journal_bdev)
3540                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3541         else if (ext4_has_feature_journal(sb) && !sbi->s_journal) {
3542                 j_inode = ext4_get_journal_inode(sb, j_inum);
3543                 if (j_inode) {
3544                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3545                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3546                         iput(j_inode);
3547                 } else {
3548                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3549                 }
3550         }
3551         sbi->s_overhead = overhead;
3552         smp_wmb();
3553         free_page((unsigned long) buf);
3554         return 0;
3555 }
3556
3557 static void ext4_clamp_want_extra_isize(struct super_block *sb)
3558 {
3559         struct ext4_sb_info *sbi = EXT4_SB(sb);
3560         struct ext4_super_block *es = sbi->s_es;
3561         unsigned def_extra_isize = sizeof(struct ext4_inode) -
3562                                                 EXT4_GOOD_OLD_INODE_SIZE;
3563
3564         if (sbi->s_inode_size == EXT4_GOOD_OLD_INODE_SIZE) {
3565                 sbi->s_want_extra_isize = 0;
3566                 return;
3567         }
3568         if (sbi->s_want_extra_isize < 4) {
3569                 sbi->s_want_extra_isize = def_extra_isize;
3570                 if (ext4_has_feature_extra_isize(sb)) {
3571                         if (sbi->s_want_extra_isize <
3572                             le16_to_cpu(es->s_want_extra_isize))
3573                                 sbi->s_want_extra_isize =
3574                                         le16_to_cpu(es->s_want_extra_isize);
3575                         if (sbi->s_want_extra_isize <
3576                             le16_to_cpu(es->s_min_extra_isize))
3577                                 sbi->s_want_extra_isize =
3578                                         le16_to_cpu(es->s_min_extra_isize);
3579                 }
3580         }
3581         /* Check if enough inode space is available */
3582         if ((sbi->s_want_extra_isize > sbi->s_inode_size) ||
3583             (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3584                                                         sbi->s_inode_size)) {
3585                 sbi->s_want_extra_isize = def_extra_isize;
3586                 ext4_msg(sb, KERN_INFO,
3587                          "required extra inode space not available");
3588         }
3589 }
3590
3591 static void ext4_set_resv_clusters(struct super_block *sb)
3592 {
3593         ext4_fsblk_t resv_clusters;
3594         struct ext4_sb_info *sbi = EXT4_SB(sb);
3595
3596         /*
3597          * There's no need to reserve anything when we aren't using extents.
3598          * The space estimates are exact, there are no unwritten extents,
3599          * hole punching doesn't need new metadata... This is needed especially
3600          * to keep ext2/3 backward compatibility.
3601          */
3602         if (!ext4_has_feature_extents(sb))
3603                 return;
3604         /*
3605          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3606          * This should cover the situations where we can not afford to run
3607          * out of space like for example punch hole, or converting
3608          * unwritten extents in delalloc path. In most cases such
3609          * allocation would require 1, or 2 blocks, higher numbers are
3610          * very rare.
3611          */
3612         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3613                          sbi->s_cluster_bits);
3614
3615         do_div(resv_clusters, 50);
3616         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3617
3618         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3619 }
3620
3621 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3622 {
3623         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3624         char *orig_data = kstrdup(data, GFP_KERNEL);
3625         struct buffer_head *bh;
3626         struct ext4_super_block *es = NULL;
3627         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3628         ext4_fsblk_t block;
3629         ext4_fsblk_t sb_block = get_sb_block(&data);
3630         ext4_fsblk_t logical_sb_block;
3631         unsigned long offset = 0;
3632         unsigned long journal_devnum = 0;
3633         unsigned long def_mount_opts;
3634         struct inode *root;
3635         const char *descr;
3636         int ret = -ENOMEM;
3637         int blocksize, clustersize;
3638         unsigned int db_count;
3639         unsigned int i;
3640         int needs_recovery, has_huge_files, has_bigalloc;
3641         __u64 blocks_count;
3642         int err = 0;
3643         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3644         ext4_group_t first_not_zeroed;
3645
3646         if ((data && !orig_data) || !sbi)
3647                 goto out_free_base;
3648
3649         sbi->s_daxdev = dax_dev;
3650         sbi->s_blockgroup_lock =
3651                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3652         if (!sbi->s_blockgroup_lock)
3653                 goto out_free_base;
3654
3655         sb->s_fs_info = sbi;
3656         sbi->s_sb = sb;
3657         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3658         sbi->s_sb_block = sb_block;
3659         if (sb->s_bdev->bd_part)
3660                 sbi->s_sectors_written_start =
3661                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
3662
3663         /* Cleanup superblock name */
3664         strreplace(sb->s_id, '/', '!');
3665
3666         /* -EINVAL is default */
3667         ret = -EINVAL;
3668         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3669         if (!blocksize) {
3670                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3671                 goto out_fail;
3672         }
3673
3674         /*
3675          * The ext4 superblock will not be buffer aligned for other than 1kB
3676          * block sizes.  We need to calculate the offset from buffer start.
3677          */
3678         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3679                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3680                 offset = do_div(logical_sb_block, blocksize);
3681         } else {
3682                 logical_sb_block = sb_block;
3683         }
3684
3685         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3686                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3687                 goto out_fail;
3688         }
3689         /*
3690          * Note: s_es must be initialized as soon as possible because
3691          *       some ext4 macro-instructions depend on its value
3692          */
3693         es = (struct ext4_super_block *) (bh->b_data + offset);
3694         sbi->s_es = es;
3695         sb->s_magic = le16_to_cpu(es->s_magic);
3696         if (sb->s_magic != EXT4_SUPER_MAGIC)
3697                 goto cantfind_ext4;
3698         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3699
3700         /* Warn if metadata_csum and gdt_csum are both set. */
3701         if (ext4_has_feature_metadata_csum(sb) &&
3702             ext4_has_feature_gdt_csum(sb))
3703                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3704                              "redundant flags; please run fsck.");
3705
3706         /* Check for a known checksum algorithm */
3707         if (!ext4_verify_csum_type(sb, es)) {
3708                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3709                          "unknown checksum algorithm.");
3710                 silent = 1;
3711                 goto cantfind_ext4;
3712         }
3713
3714         /* Load the checksum driver */
3715         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3716         if (IS_ERR(sbi->s_chksum_driver)) {
3717                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3718                 ret = PTR_ERR(sbi->s_chksum_driver);
3719                 sbi->s_chksum_driver = NULL;
3720                 goto failed_mount;
3721         }
3722
3723         /* Check superblock checksum */
3724         if (!ext4_superblock_csum_verify(sb, es)) {
3725                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3726                          "invalid superblock checksum.  Run e2fsck?");
3727                 silent = 1;
3728                 ret = -EFSBADCRC;
3729                 goto cantfind_ext4;
3730         }
3731
3732         /* Precompute checksum seed for all metadata */
3733         if (ext4_has_feature_csum_seed(sb))
3734                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3735         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3736                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3737                                                sizeof(es->s_uuid));
3738
3739         /* Set defaults before we parse the mount options */
3740         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3741         set_opt(sb, INIT_INODE_TABLE);
3742         if (def_mount_opts & EXT4_DEFM_DEBUG)
3743                 set_opt(sb, DEBUG);
3744         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3745                 set_opt(sb, GRPID);
3746         if (def_mount_opts & EXT4_DEFM_UID16)
3747                 set_opt(sb, NO_UID32);
3748         /* xattr user namespace & acls are now defaulted on */
3749         set_opt(sb, XATTR_USER);
3750 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3751         set_opt(sb, POSIX_ACL);
3752 #endif
3753         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3754         if (ext4_has_metadata_csum(sb))
3755                 set_opt(sb, JOURNAL_CHECKSUM);
3756
3757         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3758                 set_opt(sb, JOURNAL_DATA);
3759         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3760                 set_opt(sb, ORDERED_DATA);
3761         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3762                 set_opt(sb, WRITEBACK_DATA);
3763
3764         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3765                 set_opt(sb, ERRORS_PANIC);
3766         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3767                 set_opt(sb, ERRORS_CONT);
3768         else
3769                 set_opt(sb, ERRORS_RO);
3770         /* block_validity enabled by default; disable with noblock_validity */
3771         set_opt(sb, BLOCK_VALIDITY);
3772         if (def_mount_opts & EXT4_DEFM_DISCARD)
3773                 set_opt(sb, DISCARD);
3774
3775         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3776         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3777         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3778         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3779         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3780
3781         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3782                 set_opt(sb, BARRIER);
3783
3784         /*
3785          * enable delayed allocation by default
3786          * Use -o nodelalloc to turn it off
3787          */
3788         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3789             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3790                 set_opt(sb, DELALLOC);
3791
3792         /*
3793          * set default s_li_wait_mult for lazyinit, for the case there is
3794          * no mount option specified.
3795          */
3796         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3797
3798         if (sbi->s_es->s_mount_opts[0]) {
3799                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3800                                               sizeof(sbi->s_es->s_mount_opts),
3801                                               GFP_KERNEL);
3802                 if (!s_mount_opts)
3803                         goto failed_mount;
3804                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
3805                                    &journal_ioprio, 0)) {
3806                         ext4_msg(sb, KERN_WARNING,
3807                                  "failed to parse options in superblock: %s",
3808                                  s_mount_opts);
3809                 }
3810                 kfree(s_mount_opts);
3811         }
3812         sbi->s_def_mount_opt = sbi->s_mount_opt;
3813         if (!parse_options((char *) data, sb, &journal_devnum,
3814                            &journal_ioprio, 0))
3815                 goto failed_mount;
3816
3817 #ifdef CONFIG_UNICODE
3818         if (ext4_has_feature_casefold(sb) && !sbi->s_encoding) {
3819                 const struct ext4_sb_encodings *encoding_info;
3820                 struct unicode_map *encoding;
3821                 __u16 encoding_flags;
3822
3823                 if (ext4_has_feature_encrypt(sb)) {
3824                         ext4_msg(sb, KERN_ERR,
3825                                  "Can't mount with encoding and encryption");
3826                         goto failed_mount;
3827                 }
3828
3829                 if (ext4_sb_read_encoding(es, &encoding_info,
3830                                           &encoding_flags)) {
3831                         ext4_msg(sb, KERN_ERR,
3832                                  "Encoding requested by superblock is unknown");
3833                         goto failed_mount;
3834                 }
3835
3836                 encoding = utf8_load(encoding_info->version);
3837                 if (IS_ERR(encoding)) {
3838                         ext4_msg(sb, KERN_ERR,
3839                                  "can't mount with superblock charset: %s-%s "
3840                                  "not supported by the kernel. flags: 0x%x.",
3841                                  encoding_info->name, encoding_info->version,
3842                                  encoding_flags);
3843                         goto failed_mount;
3844                 }
3845                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
3846                          "%s-%s with flags 0x%hx", encoding_info->name,
3847                          encoding_info->version?:"\b", encoding_flags);
3848
3849                 sbi->s_encoding = encoding;
3850                 sbi->s_encoding_flags = encoding_flags;
3851         }
3852 #endif
3853
3854         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3855                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3856                             "with data=journal disables delayed "
3857                             "allocation and O_DIRECT support!\n");
3858                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3859                         ext4_msg(sb, KERN_ERR, "can't mount with "
3860                                  "both data=journal and delalloc");
3861                         goto failed_mount;
3862                 }
3863                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3864                         ext4_msg(sb, KERN_ERR, "can't mount with "
3865                                  "both data=journal and dioread_nolock");
3866                         goto failed_mount;
3867                 }
3868                 if (test_opt(sb, DAX)) {
3869                         ext4_msg(sb, KERN_ERR, "can't mount with "
3870                                  "both data=journal and dax");
3871                         goto failed_mount;
3872                 }
3873                 if (ext4_has_feature_encrypt(sb)) {
3874                         ext4_msg(sb, KERN_WARNING,
3875                                  "encrypted files will use data=ordered "
3876                                  "instead of data journaling mode");
3877                 }
3878                 if (test_opt(sb, DELALLOC))
3879                         clear_opt(sb, DELALLOC);
3880         } else {
3881                 sb->s_iflags |= SB_I_CGROUPWB;
3882         }
3883
3884         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
3885                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
3886
3887         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3888             (ext4_has_compat_features(sb) ||
3889              ext4_has_ro_compat_features(sb) ||
3890              ext4_has_incompat_features(sb)))
3891                 ext4_msg(sb, KERN_WARNING,
3892                        "feature flags set on rev 0 fs, "
3893                        "running e2fsck is recommended");
3894
3895         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3896                 set_opt2(sb, HURD_COMPAT);
3897                 if (ext4_has_feature_64bit(sb)) {
3898                         ext4_msg(sb, KERN_ERR,
3899                                  "The Hurd can't support 64-bit file systems");
3900                         goto failed_mount;
3901                 }
3902
3903                 /*
3904                  * ea_inode feature uses l_i_version field which is not
3905                  * available in HURD_COMPAT mode.
3906                  */
3907                 if (ext4_has_feature_ea_inode(sb)) {
3908                         ext4_msg(sb, KERN_ERR,
3909                                  "ea_inode feature is not supported for Hurd");
3910                         goto failed_mount;
3911                 }
3912         }
3913
3914         if (IS_EXT2_SB(sb)) {
3915                 if (ext2_feature_set_ok(sb))
3916                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3917                                  "using the ext4 subsystem");
3918                 else {
3919                         /*
3920                          * If we're probing be silent, if this looks like
3921                          * it's actually an ext[34] filesystem.
3922                          */
3923                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3924                                 goto failed_mount;
3925                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3926                                  "to feature incompatibilities");
3927                         goto failed_mount;
3928                 }
3929         }
3930
3931         if (IS_EXT3_SB(sb)) {
3932                 if (ext3_feature_set_ok(sb))
3933                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3934                                  "using the ext4 subsystem");
3935                 else {
3936                         /*
3937                          * If we're probing be silent, if this looks like
3938                          * it's actually an ext4 filesystem.
3939                          */
3940                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3941                                 goto failed_mount;
3942                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3943                                  "to feature incompatibilities");
3944                         goto failed_mount;
3945                 }
3946         }
3947
3948         /*
3949          * Check feature flags regardless of the revision level, since we
3950          * previously didn't change the revision level when setting the flags,
3951          * so there is a chance incompat flags are set on a rev 0 filesystem.
3952          */
3953         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
3954                 goto failed_mount;
3955
3956         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3957         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3958             blocksize > EXT4_MAX_BLOCK_SIZE) {
3959                 ext4_msg(sb, KERN_ERR,
3960                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3961                          blocksize, le32_to_cpu(es->s_log_block_size));
3962                 goto failed_mount;
3963         }
3964         if (le32_to_cpu(es->s_log_block_size) >
3965             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3966                 ext4_msg(sb, KERN_ERR,
3967                          "Invalid log block size: %u",
3968                          le32_to_cpu(es->s_log_block_size));
3969                 goto failed_mount;
3970         }
3971         if (le32_to_cpu(es->s_log_cluster_size) >
3972             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3973                 ext4_msg(sb, KERN_ERR,
3974                          "Invalid log cluster size: %u",
3975                          le32_to_cpu(es->s_log_cluster_size));
3976                 goto failed_mount;
3977         }
3978
3979         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
3980                 ext4_msg(sb, KERN_ERR,
3981                          "Number of reserved GDT blocks insanely large: %d",
3982                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
3983                 goto failed_mount;
3984         }
3985
3986         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3987                 if (ext4_has_feature_inline_data(sb)) {
3988                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
3989                                         " that may contain inline data");
3990                         goto failed_mount;
3991                 }
3992                 if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
3993                         ext4_msg(sb, KERN_ERR,
3994                                 "DAX unsupported by block device.");
3995                         goto failed_mount;
3996                 }
3997         }
3998
3999         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4000                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4001                          es->s_encryption_level);
4002                 goto failed_mount;
4003         }
4004
4005         if (sb->s_blocksize != blocksize) {
4006                 /* Validate the filesystem blocksize */
4007                 if (!sb_set_blocksize(sb, blocksize)) {
4008                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4009                                         blocksize);
4010                         goto failed_mount;
4011                 }
4012
4013                 brelse(bh);
4014                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4015                 offset = do_div(logical_sb_block, blocksize);
4016                 bh = sb_bread_unmovable(sb, logical_sb_block);
4017                 if (!bh) {
4018                         ext4_msg(sb, KERN_ERR,
4019                                "Can't read superblock on 2nd try");
4020                         goto failed_mount;
4021                 }
4022                 es = (struct ext4_super_block *)(bh->b_data + offset);
4023                 sbi->s_es = es;
4024                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4025                         ext4_msg(sb, KERN_ERR,
4026                                "Magic mismatch, very weird!");
4027                         goto failed_mount;
4028                 }
4029         }
4030
4031         has_huge_files = ext4_has_feature_huge_file(sb);
4032         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4033                                                       has_huge_files);
4034         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4035
4036         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4037                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4038                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4039         } else {
4040                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4041                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4042                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4043                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4044                                  sbi->s_first_ino);
4045                         goto failed_mount;
4046                 }
4047                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4048                     (!is_power_of_2(sbi->s_inode_size)) ||
4049                     (sbi->s_inode_size > blocksize)) {
4050                         ext4_msg(sb, KERN_ERR,
4051                                "unsupported inode size: %d",
4052                                sbi->s_inode_size);
4053                         goto failed_mount;
4054                 }
4055                 /*
4056                  * i_atime_extra is the last extra field available for [acm]times in
4057                  * struct ext4_inode. Checking for that field should suffice to ensure
4058                  * we have extra space for all three.
4059                  */
4060                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4061                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4062                         sb->s_time_gran = 1;
4063                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4064                 } else {
4065                         sb->s_time_gran = NSEC_PER_SEC;
4066                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4067                 }
4068
4069                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4070         }
4071
4072         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4073         if (ext4_has_feature_64bit(sb)) {
4074                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4075                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4076                     !is_power_of_2(sbi->s_desc_size)) {
4077                         ext4_msg(sb, KERN_ERR,
4078                                "unsupported descriptor size %lu",
4079                                sbi->s_desc_size);
4080                         goto failed_mount;
4081                 }
4082         } else
4083                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4084
4085         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4086         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4087
4088         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4089         if (sbi->s_inodes_per_block == 0)
4090                 goto cantfind_ext4;
4091         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4092             sbi->s_inodes_per_group > blocksize * 8) {
4093                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4094                          sbi->s_blocks_per_group);
4095                 goto failed_mount;
4096         }
4097         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4098                                         sbi->s_inodes_per_block;
4099         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4100         sbi->s_sbh = bh;
4101         sbi->s_mount_state = le16_to_cpu(es->s_state);
4102         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4103         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4104
4105         for (i = 0; i < 4; i++)
4106                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4107         sbi->s_def_hash_version = es->s_def_hash_version;
4108         if (ext4_has_feature_dir_index(sb)) {
4109                 i = le32_to_cpu(es->s_flags);
4110                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4111                         sbi->s_hash_unsigned = 3;
4112                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4113 #ifdef __CHAR_UNSIGNED__
4114                         if (!sb_rdonly(sb))
4115                                 es->s_flags |=
4116                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4117                         sbi->s_hash_unsigned = 3;
4118 #else
4119                         if (!sb_rdonly(sb))
4120                                 es->s_flags |=
4121                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4122 #endif
4123                 }
4124         }
4125
4126         /* Handle clustersize */
4127         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4128         has_bigalloc = ext4_has_feature_bigalloc(sb);
4129         if (has_bigalloc) {
4130                 if (clustersize < blocksize) {
4131                         ext4_msg(sb, KERN_ERR,
4132                                  "cluster size (%d) smaller than "
4133                                  "block size (%d)", clustersize, blocksize);
4134                         goto failed_mount;
4135                 }
4136                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4137                         le32_to_cpu(es->s_log_block_size);
4138                 sbi->s_clusters_per_group =
4139                         le32_to_cpu(es->s_clusters_per_group);
4140                 if (sbi->s_clusters_per_group > blocksize * 8) {
4141                         ext4_msg(sb, KERN_ERR,
4142                                  "#clusters per group too big: %lu",
4143                                  sbi->s_clusters_per_group);
4144                         goto failed_mount;
4145                 }
4146                 if (sbi->s_blocks_per_group !=
4147                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4148                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4149                                  "clusters per group (%lu) inconsistent",
4150                                  sbi->s_blocks_per_group,
4151                                  sbi->s_clusters_per_group);
4152                         goto failed_mount;
4153                 }
4154         } else {
4155                 if (clustersize != blocksize) {
4156                         ext4_msg(sb, KERN_ERR,
4157                                  "fragment/cluster size (%d) != "
4158                                  "block size (%d)", clustersize, blocksize);
4159                         goto failed_mount;
4160                 }
4161                 if (sbi->s_blocks_per_group > blocksize * 8) {
4162                         ext4_msg(sb, KERN_ERR,
4163                                  "#blocks per group too big: %lu",
4164                                  sbi->s_blocks_per_group);
4165                         goto failed_mount;
4166                 }
4167                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4168                 sbi->s_cluster_bits = 0;
4169         }
4170         sbi->s_cluster_ratio = clustersize / blocksize;
4171
4172         /* Do we have standard group size of clustersize * 8 blocks ? */
4173         if (sbi->s_blocks_per_group == clustersize << 3)
4174                 set_opt2(sb, STD_GROUP_SIZE);
4175
4176         /*
4177          * Test whether we have more sectors than will fit in sector_t,
4178          * and whether the max offset is addressable by the page cache.
4179          */
4180         err = generic_check_addressable(sb->s_blocksize_bits,
4181                                         ext4_blocks_count(es));
4182         if (err) {
4183                 ext4_msg(sb, KERN_ERR, "filesystem"
4184                          " too large to mount safely on this system");
4185                 goto failed_mount;
4186         }
4187
4188         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4189                 goto cantfind_ext4;
4190
4191         /* check blocks count against device size */
4192         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4193         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4194                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4195                        "exceeds size of device (%llu blocks)",
4196                        ext4_blocks_count(es), blocks_count);
4197                 goto failed_mount;
4198         }
4199
4200         /*
4201          * It makes no sense for the first data block to be beyond the end
4202          * of the filesystem.
4203          */
4204         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4205                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4206                          "block %u is beyond end of filesystem (%llu)",
4207                          le32_to_cpu(es->s_first_data_block),
4208                          ext4_blocks_count(es));
4209                 goto failed_mount;
4210         }
4211         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4212             (sbi->s_cluster_ratio == 1)) {
4213                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4214                          "block is 0 with a 1k block and cluster size");
4215                 goto failed_mount;
4216         }
4217
4218         blocks_count = (ext4_blocks_count(es) -
4219                         le32_to_cpu(es->s_first_data_block) +
4220                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4221         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4222         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4223                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
4224                        "(block count %llu, first data block %u, "
4225                        "blocks per group %lu)", sbi->s_groups_count,
4226                        ext4_blocks_count(es),
4227                        le32_to_cpu(es->s_first_data_block),
4228                        EXT4_BLOCKS_PER_GROUP(sb));
4229                 goto failed_mount;
4230         }
4231         sbi->s_groups_count = blocks_count;
4232         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4233                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4234         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4235             le32_to_cpu(es->s_inodes_count)) {
4236                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4237                          le32_to_cpu(es->s_inodes_count),
4238                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4239                 ret = -EINVAL;
4240                 goto failed_mount;
4241         }
4242         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4243                    EXT4_DESC_PER_BLOCK(sb);
4244         if (ext4_has_feature_meta_bg(sb)) {
4245                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4246                         ext4_msg(sb, KERN_WARNING,
4247                                  "first meta block group too large: %u "
4248                                  "(group descriptor block count %u)",
4249                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4250                         goto failed_mount;
4251                 }
4252         }
4253         sbi->s_group_desc = kvmalloc_array(db_count,
4254                                            sizeof(struct buffer_head *),
4255                                            GFP_KERNEL);
4256         if (sbi->s_group_desc == NULL) {
4257                 ext4_msg(sb, KERN_ERR, "not enough memory");
4258                 ret = -ENOMEM;
4259                 goto failed_mount;
4260         }
4261
4262         bgl_lock_init(sbi->s_blockgroup_lock);
4263
4264         /* Pre-read the descriptors into the buffer cache */
4265         for (i = 0; i < db_count; i++) {
4266                 block = descriptor_loc(sb, logical_sb_block, i);
4267                 sb_breadahead(sb, block);
4268         }
4269
4270         for (i = 0; i < db_count; i++) {
4271                 block = descriptor_loc(sb, logical_sb_block, i);
4272                 sbi->s_group_desc[i] = sb_bread_unmovable(sb, block);
4273                 if (!sbi->s_group_desc[i]) {
4274                         ext4_msg(sb, KERN_ERR,
4275                                "can't read group descriptor %d", i);
4276                         db_count = i;
4277                         goto failed_mount2;
4278                 }
4279         }
4280         sbi->s_gdb_count = db_count;
4281         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4282                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4283                 ret = -EFSCORRUPTED;
4284                 goto failed_mount2;
4285         }
4286
4287         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4288
4289         /* Register extent status tree shrinker */
4290         if (ext4_es_register_shrinker(sbi))
4291                 goto failed_mount3;
4292
4293         sbi->s_stripe = ext4_get_stripe_size(sbi);
4294         sbi->s_extent_max_zeroout_kb = 32;
4295
4296         /*
4297          * set up enough so that it can read an inode
4298          */
4299         sb->s_op = &ext4_sops;
4300         sb->s_export_op = &ext4_export_ops;
4301         sb->s_xattr = ext4_xattr_handlers;
4302 #ifdef CONFIG_FS_ENCRYPTION
4303         sb->s_cop = &ext4_cryptops;
4304 #endif
4305 #ifdef CONFIG_FS_VERITY
4306         sb->s_vop = &ext4_verityops;
4307 #endif
4308 #ifdef CONFIG_QUOTA
4309         sb->dq_op = &ext4_quota_operations;
4310         if (ext4_has_feature_quota(sb))
4311                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4312         else
4313                 sb->s_qcop = &ext4_qctl_operations;
4314         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4315 #endif
4316         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4317
4318         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4319         mutex_init(&sbi->s_orphan_lock);
4320
4321         sb->s_root = NULL;
4322
4323         needs_recovery = (es->s_last_orphan != 0 ||
4324                           ext4_has_feature_journal_needs_recovery(sb));
4325
4326         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4327                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4328                         goto failed_mount3a;
4329
4330         /*
4331          * The first inode we look at is the journal inode.  Don't try
4332          * root first: it may be modified in the journal!
4333          */
4334         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4335                 err = ext4_load_journal(sb, es, journal_devnum);
4336                 if (err)
4337                         goto failed_mount3a;
4338         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4339                    ext4_has_feature_journal_needs_recovery(sb)) {
4340                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4341                        "suppressed and not mounted read-only");
4342                 goto failed_mount_wq;
4343         } else {
4344                 /* Nojournal mode, all journal mount options are illegal */
4345                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4346                         ext4_msg(sb, KERN_ERR, "can't mount with "
4347                                  "journal_checksum, fs mounted w/o journal");
4348                         goto failed_mount_wq;
4349                 }
4350                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4351                         ext4_msg(sb, KERN_ERR, "can't mount with "
4352                                  "journal_async_commit, fs mounted w/o journal");
4353                         goto failed_mount_wq;
4354                 }
4355                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4356                         ext4_msg(sb, KERN_ERR, "can't mount with "
4357                                  "commit=%lu, fs mounted w/o journal",
4358                                  sbi->s_commit_interval / HZ);
4359                         goto failed_mount_wq;
4360                 }
4361                 if (EXT4_MOUNT_DATA_FLAGS &
4362                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4363                         ext4_msg(sb, KERN_ERR, "can't mount with "
4364                                  "data=, fs mounted w/o journal");
4365                         goto failed_mount_wq;
4366                 }
4367                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4368                 clear_opt(sb, JOURNAL_CHECKSUM);
4369                 clear_opt(sb, DATA_FLAGS);
4370                 sbi->s_journal = NULL;
4371                 needs_recovery = 0;
4372                 goto no_journal;
4373         }
4374
4375         if (ext4_has_feature_64bit(sb) &&
4376             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4377                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4378                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4379                 goto failed_mount_wq;
4380         }
4381
4382         if (!set_journal_csum_feature_set(sb)) {
4383                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4384                          "feature set");
4385                 goto failed_mount_wq;
4386         }
4387
4388         /* We have now updated the journal if required, so we can
4389          * validate the data journaling mode. */
4390         switch (test_opt(sb, DATA_FLAGS)) {
4391         case 0:
4392                 /* No mode set, assume a default based on the journal
4393                  * capabilities: ORDERED_DATA if the journal can
4394                  * cope, else JOURNAL_DATA
4395                  */
4396                 if (jbd2_journal_check_available_features
4397                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4398                         set_opt(sb, ORDERED_DATA);
4399                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4400                 } else {
4401                         set_opt(sb, JOURNAL_DATA);
4402                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4403                 }
4404                 break;
4405
4406         case EXT4_MOUNT_ORDERED_DATA:
4407         case EXT4_MOUNT_WRITEBACK_DATA:
4408                 if (!jbd2_journal_check_available_features
4409                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4410                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4411                                "requested data journaling mode");
4412                         goto failed_mount_wq;
4413                 }
4414         default:
4415                 break;
4416         }
4417
4418         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4419             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4420                 ext4_msg(sb, KERN_ERR, "can't mount with "
4421                         "journal_async_commit in data=ordered mode");
4422                 goto failed_mount_wq;
4423         }
4424
4425         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4426
4427         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4428
4429 no_journal:
4430         if (!test_opt(sb, NO_MBCACHE)) {
4431                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4432                 if (!sbi->s_ea_block_cache) {
4433                         ext4_msg(sb, KERN_ERR,
4434                                  "Failed to create ea_block_cache");
4435                         goto failed_mount_wq;
4436                 }
4437
4438                 if (ext4_has_feature_ea_inode(sb)) {
4439                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4440                         if (!sbi->s_ea_inode_cache) {
4441                                 ext4_msg(sb, KERN_ERR,
4442                                          "Failed to create ea_inode_cache");
4443                                 goto failed_mount_wq;
4444                         }
4445                 }
4446         }
4447
4448         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4449                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4450                 goto failed_mount_wq;
4451         }
4452
4453         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4454             !ext4_has_feature_encrypt(sb)) {
4455                 ext4_set_feature_encrypt(sb);
4456                 ext4_commit_super(sb, 1);
4457         }
4458
4459         /*
4460          * Get the # of file system overhead blocks from the
4461          * superblock if present.
4462          */
4463         if (es->s_overhead_clusters)
4464                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4465         else {
4466                 err = ext4_calculate_overhead(sb);
4467                 if (err)
4468                         goto failed_mount_wq;
4469         }
4470
4471         /*
4472          * The maximum number of concurrent works can be high and
4473          * concurrency isn't really necessary.  Limit it to 1.
4474          */
4475         EXT4_SB(sb)->rsv_conversion_wq =
4476                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4477         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4478                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4479                 ret = -ENOMEM;
4480                 goto failed_mount4;
4481         }
4482
4483         /*
4484          * The jbd2_journal_load will have done any necessary log recovery,
4485          * so we can safely mount the rest of the filesystem now.
4486          */
4487
4488         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4489         if (IS_ERR(root)) {
4490                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4491                 ret = PTR_ERR(root);
4492                 root = NULL;
4493                 goto failed_mount4;
4494         }
4495         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4496                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4497                 iput(root);
4498                 goto failed_mount4;
4499         }
4500
4501 #ifdef CONFIG_UNICODE
4502         if (sbi->s_encoding)
4503                 sb->s_d_op = &ext4_dentry_ops;
4504 #endif
4505
4506         sb->s_root = d_make_root(root);
4507         if (!sb->s_root) {
4508                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4509                 ret = -ENOMEM;
4510                 goto failed_mount4;
4511         }
4512
4513         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4514         if (ret == -EROFS) {
4515                 sb->s_flags |= SB_RDONLY;
4516                 ret = 0;
4517         } else if (ret)
4518                 goto failed_mount4a;
4519
4520         ext4_clamp_want_extra_isize(sb);
4521
4522         ext4_set_resv_clusters(sb);
4523
4524         err = ext4_setup_system_zone(sb);
4525         if (err) {
4526                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4527                          "zone (%d)", err);
4528                 goto failed_mount4a;
4529         }
4530
4531         ext4_ext_init(sb);
4532         err = ext4_mb_init(sb);
4533         if (err) {
4534                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4535                          err);
4536                 goto failed_mount5;
4537         }
4538
4539         block = ext4_count_free_clusters(sb);
4540         ext4_free_blocks_count_set(sbi->s_es,
4541                                    EXT4_C2B(sbi, block));
4542         ext4_superblock_csum_set(sb);
4543         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4544                                   GFP_KERNEL);
4545         if (!err) {
4546                 unsigned long freei = ext4_count_free_inodes(sb);
4547                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4548                 ext4_superblock_csum_set(sb);
4549                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4550                                           GFP_KERNEL);
4551         }
4552         if (!err)
4553                 err = percpu_counter_init(&sbi->s_dirs_counter,
4554                                           ext4_count_dirs(sb), GFP_KERNEL);
4555         if (!err)
4556                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4557                                           GFP_KERNEL);
4558         if (!err)
4559                 err = percpu_init_rwsem(&sbi->s_journal_flag_rwsem);
4560
4561         if (err) {
4562                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4563                 goto failed_mount6;
4564         }
4565
4566         if (ext4_has_feature_flex_bg(sb))
4567                 if (!ext4_fill_flex_info(sb)) {
4568                         ext4_msg(sb, KERN_ERR,
4569                                "unable to initialize "
4570                                "flex_bg meta info!");
4571                         goto failed_mount6;
4572                 }
4573
4574         err = ext4_register_li_request(sb, first_not_zeroed);
4575         if (err)
4576                 goto failed_mount6;
4577
4578         err = ext4_register_sysfs(sb);
4579         if (err)
4580                 goto failed_mount7;
4581
4582 #ifdef CONFIG_QUOTA
4583         /* Enable quota usage during mount. */
4584         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4585                 err = ext4_enable_quotas(sb);
4586                 if (err)
4587                         goto failed_mount8;
4588         }
4589 #endif  /* CONFIG_QUOTA */
4590
4591         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4592         ext4_orphan_cleanup(sb, es);
4593         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4594         if (needs_recovery) {
4595                 ext4_msg(sb, KERN_INFO, "recovery complete");
4596                 ext4_mark_recovery_complete(sb, es);
4597         }
4598         if (EXT4_SB(sb)->s_journal) {
4599                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4600                         descr = " journalled data mode";
4601                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4602                         descr = " ordered data mode";
4603                 else
4604                         descr = " writeback data mode";
4605         } else
4606                 descr = "out journal";
4607
4608         if (test_opt(sb, DISCARD)) {
4609                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4610                 if (!blk_queue_discard(q))
4611                         ext4_msg(sb, KERN_WARNING,
4612                                  "mounting with \"discard\" option, but "
4613                                  "the device does not support discard");
4614         }
4615
4616         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4617                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4618                          "Opts: %.*s%s%s", descr,
4619                          (int) sizeof(sbi->s_es->s_mount_opts),
4620                          sbi->s_es->s_mount_opts,
4621                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4622
4623         if (es->s_error_count)
4624                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4625
4626         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4627         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4628         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4629         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4630
4631         kfree(orig_data);
4632         return 0;
4633
4634 cantfind_ext4:
4635         if (!silent)
4636                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4637         goto failed_mount;
4638
4639 #ifdef CONFIG_QUOTA
4640 failed_mount8:
4641         ext4_unregister_sysfs(sb);
4642 #endif
4643 failed_mount7:
4644         ext4_unregister_li_request(sb);
4645 failed_mount6:
4646         ext4_mb_release(sb);
4647         if (sbi->s_flex_groups)
4648                 kvfree(sbi->s_flex_groups);
4649         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4650         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4651         percpu_counter_destroy(&sbi->s_dirs_counter);
4652         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4653         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
4654 failed_mount5:
4655         ext4_ext_release(sb);
4656         ext4_release_system_zone(sb);
4657 failed_mount4a:
4658         dput(sb->s_root);
4659         sb->s_root = NULL;
4660 failed_mount4:
4661         ext4_msg(sb, KERN_ERR, "mount failed");
4662         if (EXT4_SB(sb)->rsv_conversion_wq)
4663                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4664 failed_mount_wq:
4665         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4666         sbi->s_ea_inode_cache = NULL;
4667
4668         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4669         sbi->s_ea_block_cache = NULL;
4670
4671         if (sbi->s_journal) {
4672                 jbd2_journal_destroy(sbi->s_journal);
4673                 sbi->s_journal = NULL;
4674         }
4675 failed_mount3a:
4676         ext4_es_unregister_shrinker(sbi);
4677 failed_mount3:
4678         del_timer_sync(&sbi->s_err_report);
4679         if (sbi->s_mmp_tsk)
4680                 kthread_stop(sbi->s_mmp_tsk);
4681 failed_mount2:
4682         for (i = 0; i < db_count; i++)
4683                 brelse(sbi->s_group_desc[i]);
4684         kvfree(sbi->s_group_desc);
4685 failed_mount:
4686         if (sbi->s_chksum_driver)
4687                 crypto_free_shash(sbi->s_chksum_driver);
4688
4689 #ifdef CONFIG_UNICODE
4690         utf8_unload(sbi->s_encoding);
4691 #endif
4692
4693 #ifdef CONFIG_QUOTA
4694         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4695                 kfree(get_qf_name(sb, sbi, i));
4696 #endif
4697         ext4_blkdev_remove(sbi);
4698         brelse(bh);
4699 out_fail:
4700         sb->s_fs_info = NULL;
4701         kfree(sbi->s_blockgroup_lock);
4702 out_free_base:
4703         kfree(sbi);
4704         kfree(orig_data);
4705         fs_put_dax(dax_dev);
4706         return err ? err : ret;
4707 }
4708
4709 /*
4710  * Setup any per-fs journal parameters now.  We'll do this both on
4711  * initial mount, once the journal has been initialised but before we've
4712  * done any recovery; and again on any subsequent remount.
4713  */
4714 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4715 {
4716         struct ext4_sb_info *sbi = EXT4_SB(sb);
4717
4718         journal->j_commit_interval = sbi->s_commit_interval;
4719         journal->j_min_batch_time = sbi->s_min_batch_time;
4720         journal->j_max_batch_time = sbi->s_max_batch_time;
4721
4722         write_lock(&journal->j_state_lock);
4723         if (test_opt(sb, BARRIER))
4724                 journal->j_flags |= JBD2_BARRIER;
4725         else
4726                 journal->j_flags &= ~JBD2_BARRIER;
4727         if (test_opt(sb, DATA_ERR_ABORT))
4728                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4729         else
4730                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4731         write_unlock(&journal->j_state_lock);
4732 }
4733
4734 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4735                                              unsigned int journal_inum)
4736 {
4737         struct inode *journal_inode;
4738
4739         /*
4740          * Test for the existence of a valid inode on disk.  Bad things
4741          * happen if we iget() an unused inode, as the subsequent iput()
4742          * will try to delete it.
4743          */
4744         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
4745         if (IS_ERR(journal_inode)) {
4746                 ext4_msg(sb, KERN_ERR, "no journal found");
4747                 return NULL;
4748         }
4749         if (!journal_inode->i_nlink) {
4750                 make_bad_inode(journal_inode);
4751                 iput(journal_inode);
4752                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4753                 return NULL;
4754         }
4755
4756         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4757                   journal_inode, journal_inode->i_size);
4758         if (!S_ISREG(journal_inode->i_mode)) {
4759                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4760                 iput(journal_inode);
4761                 return NULL;
4762         }
4763         return journal_inode;
4764 }
4765
4766 static journal_t *ext4_get_journal(struct super_block *sb,
4767                                    unsigned int journal_inum)
4768 {
4769         struct inode *journal_inode;
4770         journal_t *journal;
4771
4772         BUG_ON(!ext4_has_feature_journal(sb));
4773
4774         journal_inode = ext4_get_journal_inode(sb, journal_inum);
4775         if (!journal_inode)
4776                 return NULL;
4777
4778         journal = jbd2_journal_init_inode(journal_inode);
4779         if (!journal) {
4780                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4781                 iput(journal_inode);
4782                 return NULL;
4783         }
4784         journal->j_private = sb;
4785         ext4_init_journal_params(sb, journal);
4786         return journal;
4787 }
4788
4789 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4790                                        dev_t j_dev)
4791 {
4792         struct buffer_head *bh;
4793         journal_t *journal;
4794         ext4_fsblk_t start;
4795         ext4_fsblk_t len;
4796         int hblock, blocksize;
4797         ext4_fsblk_t sb_block;
4798         unsigned long offset;
4799         struct ext4_super_block *es;
4800         struct block_device *bdev;
4801
4802         BUG_ON(!ext4_has_feature_journal(sb));
4803
4804         bdev = ext4_blkdev_get(j_dev, sb);
4805         if (bdev == NULL)
4806                 return NULL;
4807
4808         blocksize = sb->s_blocksize;
4809         hblock = bdev_logical_block_size(bdev);
4810         if (blocksize < hblock) {
4811                 ext4_msg(sb, KERN_ERR,
4812                         "blocksize too small for journal device");
4813                 goto out_bdev;
4814         }
4815
4816         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4817         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4818         set_blocksize(bdev, blocksize);
4819         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4820                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4821                        "external journal");
4822                 goto out_bdev;
4823         }
4824
4825         es = (struct ext4_super_block *) (bh->b_data + offset);
4826         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4827             !(le32_to_cpu(es->s_feature_incompat) &
4828               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4829                 ext4_msg(sb, KERN_ERR, "external journal has "
4830                                         "bad superblock");
4831                 brelse(bh);
4832                 goto out_bdev;
4833         }
4834
4835         if ((le32_to_cpu(es->s_feature_ro_compat) &
4836              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4837             es->s_checksum != ext4_superblock_csum(sb, es)) {
4838                 ext4_msg(sb, KERN_ERR, "external journal has "
4839                                        "corrupt superblock");
4840                 brelse(bh);
4841                 goto out_bdev;
4842         }
4843
4844         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4845                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4846                 brelse(bh);
4847                 goto out_bdev;
4848         }
4849
4850         len = ext4_blocks_count(es);
4851         start = sb_block + 1;
4852         brelse(bh);     /* we're done with the superblock */
4853
4854         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4855                                         start, len, blocksize);
4856         if (!journal) {
4857                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4858                 goto out_bdev;
4859         }
4860         journal->j_private = sb;
4861         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4862         wait_on_buffer(journal->j_sb_buffer);
4863         if (!buffer_uptodate(journal->j_sb_buffer)) {
4864                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4865                 goto out_journal;
4866         }
4867         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4868                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4869                                         "user (unsupported) - %d",
4870                         be32_to_cpu(journal->j_superblock->s_nr_users));
4871                 goto out_journal;
4872         }
4873         EXT4_SB(sb)->journal_bdev = bdev;
4874         ext4_init_journal_params(sb, journal);
4875         return journal;
4876
4877 out_journal:
4878         jbd2_journal_destroy(journal);
4879 out_bdev:
4880         ext4_blkdev_put(bdev);
4881         return NULL;
4882 }
4883
4884 static int ext4_load_journal(struct super_block *sb,
4885                              struct ext4_super_block *es,
4886                              unsigned long journal_devnum)
4887 {
4888         journal_t *journal;
4889         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4890         dev_t journal_dev;
4891         int err = 0;
4892         int really_read_only;
4893
4894         BUG_ON(!ext4_has_feature_journal(sb));
4895
4896         if (journal_devnum &&
4897             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4898                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4899                         "numbers have changed");
4900                 journal_dev = new_decode_dev(journal_devnum);
4901         } else
4902                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4903
4904         really_read_only = bdev_read_only(sb->s_bdev);
4905
4906         /*
4907          * Are we loading a blank journal or performing recovery after a
4908          * crash?  For recovery, we need to check in advance whether we
4909          * can get read-write access to the device.
4910          */
4911         if (ext4_has_feature_journal_needs_recovery(sb)) {
4912                 if (sb_rdonly(sb)) {
4913                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4914                                         "required on readonly filesystem");
4915                         if (really_read_only) {
4916                                 ext4_msg(sb, KERN_ERR, "write access "
4917                                         "unavailable, cannot proceed "
4918                                         "(try mounting with noload)");
4919                                 return -EROFS;
4920                         }
4921                         ext4_msg(sb, KERN_INFO, "write access will "
4922                                "be enabled during recovery");
4923                 }
4924         }
4925
4926         if (journal_inum && journal_dev) {
4927                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4928                        "and inode journals!");
4929                 return -EINVAL;
4930         }
4931
4932         if (journal_inum) {
4933                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4934                         return -EINVAL;
4935         } else {
4936                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4937                         return -EINVAL;
4938         }
4939
4940         if (!(journal->j_flags & JBD2_BARRIER))
4941                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4942
4943         if (!ext4_has_feature_journal_needs_recovery(sb))
4944                 err = jbd2_journal_wipe(journal, !really_read_only);
4945         if (!err) {
4946                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4947                 if (save)
4948                         memcpy(save, ((char *) es) +
4949                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4950                 err = jbd2_journal_load(journal);
4951                 if (save)
4952                         memcpy(((char *) es) + EXT4_S_ERR_START,
4953                                save, EXT4_S_ERR_LEN);
4954                 kfree(save);
4955         }
4956
4957         if (err) {
4958                 ext4_msg(sb, KERN_ERR, "error loading journal");
4959                 jbd2_journal_destroy(journal);
4960                 return err;
4961         }
4962
4963         EXT4_SB(sb)->s_journal = journal;
4964         ext4_clear_journal_err(sb, es);
4965
4966         if (!really_read_only && journal_devnum &&
4967             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4968                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4969
4970                 /* Make sure we flush the recovery flag to disk. */
4971                 ext4_commit_super(sb, 1);
4972         }
4973
4974         return 0;
4975 }
4976
4977 static int ext4_commit_super(struct super_block *sb, int sync)
4978 {
4979         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4980         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4981         int error = 0;
4982
4983         if (!sbh || block_device_ejected(sb))
4984                 return error;
4985
4986         /*
4987          * The superblock bh should be mapped, but it might not be if the
4988          * device was hot-removed. Not much we can do but fail the I/O.
4989          */
4990         if (!buffer_mapped(sbh))
4991                 return error;
4992
4993         /*
4994          * If the file system is mounted read-only, don't update the
4995          * superblock write time.  This avoids updating the superblock
4996          * write time when we are mounting the root file system
4997          * read/only but we need to replay the journal; at that point,
4998          * for people who are east of GMT and who make their clock
4999          * tick in localtime for Windows bug-for-bug compatibility,
5000          * the clock is set in the future, and this will cause e2fsck
5001          * to complain and force a full file system check.
5002          */
5003         if (!(sb->s_flags & SB_RDONLY))
5004                 ext4_update_tstamp(es, s_wtime);
5005         if (sb->s_bdev->bd_part)
5006                 es->s_kbytes_written =
5007                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5008                             ((part_stat_read(sb->s_bdev->bd_part,
5009                                              sectors[STAT_WRITE]) -
5010                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
5011         else
5012                 es->s_kbytes_written =
5013                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5014         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5015                 ext4_free_blocks_count_set(es,
5016                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5017                                 &EXT4_SB(sb)->s_freeclusters_counter)));
5018         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5019                 es->s_free_inodes_count =
5020                         cpu_to_le32(percpu_counter_sum_positive(
5021                                 &EXT4_SB(sb)->s_freeinodes_counter));
5022         BUFFER_TRACE(sbh, "marking dirty");
5023         ext4_superblock_csum_set(sb);
5024         if (sync)
5025                 lock_buffer(sbh);
5026         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5027                 /*
5028                  * Oh, dear.  A previous attempt to write the
5029                  * superblock failed.  This could happen because the
5030                  * USB device was yanked out.  Or it could happen to
5031                  * be a transient write error and maybe the block will
5032                  * be remapped.  Nothing we can do but to retry the
5033                  * write and hope for the best.
5034                  */
5035                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5036                        "superblock detected");
5037                 clear_buffer_write_io_error(sbh);
5038                 set_buffer_uptodate(sbh);
5039         }
5040         mark_buffer_dirty(sbh);
5041         if (sync) {
5042                 unlock_buffer(sbh);
5043                 error = __sync_dirty_buffer(sbh,
5044                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5045                 if (buffer_write_io_error(sbh)) {
5046                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5047                                "superblock");
5048                         clear_buffer_write_io_error(sbh);
5049                         set_buffer_uptodate(sbh);
5050                 }
5051         }
5052         return error;
5053 }
5054
5055 /*
5056  * Have we just finished recovery?  If so, and if we are mounting (or
5057  * remounting) the filesystem readonly, then we will end up with a
5058  * consistent fs on disk.  Record that fact.
5059  */
5060 static void ext4_mark_recovery_complete(struct super_block *sb,
5061                                         struct ext4_super_block *es)
5062 {
5063         journal_t *journal = EXT4_SB(sb)->s_journal;
5064
5065         if (!ext4_has_feature_journal(sb)) {
5066                 BUG_ON(journal != NULL);
5067                 return;
5068         }
5069         jbd2_journal_lock_updates(journal);
5070         if (jbd2_journal_flush(journal) < 0)
5071                 goto out;
5072
5073         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5074                 ext4_clear_feature_journal_needs_recovery(sb);
5075                 ext4_commit_super(sb, 1);
5076         }
5077
5078 out:
5079         jbd2_journal_unlock_updates(journal);
5080 }
5081
5082 /*
5083  * If we are mounting (or read-write remounting) a filesystem whose journal
5084  * has recorded an error from a previous lifetime, move that error to the
5085  * main filesystem now.
5086  */
5087 static void ext4_clear_journal_err(struct super_block *sb,
5088                                    struct ext4_super_block *es)
5089 {
5090         journal_t *journal;
5091         int j_errno;
5092         const char *errstr;
5093
5094         BUG_ON(!ext4_has_feature_journal(sb));
5095
5096         journal = EXT4_SB(sb)->s_journal;
5097
5098         /*
5099          * Now check for any error status which may have been recorded in the
5100          * journal by a prior ext4_error() or ext4_abort()
5101          */
5102
5103         j_errno = jbd2_journal_errno(journal);
5104         if (j_errno) {
5105                 char nbuf[16];
5106
5107                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5108                 ext4_warning(sb, "Filesystem error recorded "
5109                              "from previous mount: %s", errstr);
5110                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5111
5112                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5113                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5114                 ext4_commit_super(sb, 1);
5115
5116                 jbd2_journal_clear_err(journal);
5117                 jbd2_journal_update_sb_errno(journal);
5118         }
5119 }
5120
5121 /*
5122  * Force the running and committing transactions to commit,
5123  * and wait on the commit.
5124  */
5125 int ext4_force_commit(struct super_block *sb)
5126 {
5127         journal_t *journal;
5128
5129         if (sb_rdonly(sb))
5130                 return 0;
5131
5132         journal = EXT4_SB(sb)->s_journal;
5133         return ext4_journal_force_commit(journal);
5134 }
5135
5136 static int ext4_sync_fs(struct super_block *sb, int wait)
5137 {
5138         int ret = 0;
5139         tid_t target;
5140         bool needs_barrier = false;
5141         struct ext4_sb_info *sbi = EXT4_SB(sb);
5142
5143         if (unlikely(ext4_forced_shutdown(sbi)))
5144                 return 0;
5145
5146         trace_ext4_sync_fs(sb, wait);
5147         flush_workqueue(sbi->rsv_conversion_wq);
5148         /*
5149          * Writeback quota in non-journalled quota case - journalled quota has
5150          * no dirty dquots
5151          */
5152         dquot_writeback_dquots(sb, -1);
5153         /*
5154          * Data writeback is possible w/o journal transaction, so barrier must
5155          * being sent at the end of the function. But we can skip it if
5156          * transaction_commit will do it for us.
5157          */
5158         if (sbi->s_journal) {
5159                 target = jbd2_get_latest_transaction(sbi->s_journal);
5160                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5161                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5162                         needs_barrier = true;
5163
5164                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5165                         if (wait)
5166                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5167                                                            target);
5168                 }
5169         } else if (wait && test_opt(sb, BARRIER))
5170                 needs_barrier = true;
5171         if (needs_barrier) {
5172                 int err;
5173                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
5174                 if (!ret)
5175                         ret = err;
5176         }
5177
5178         return ret;
5179 }
5180
5181 /*
5182  * LVM calls this function before a (read-only) snapshot is created.  This
5183  * gives us a chance to flush the journal completely and mark the fs clean.
5184  *
5185  * Note that only this function cannot bring a filesystem to be in a clean
5186  * state independently. It relies on upper layer to stop all data & metadata
5187  * modifications.
5188  */
5189 static int ext4_freeze(struct super_block *sb)
5190 {
5191         int error = 0;
5192         journal_t *journal;
5193
5194         if (sb_rdonly(sb))
5195                 return 0;
5196
5197         journal = EXT4_SB(sb)->s_journal;
5198
5199         if (journal) {
5200                 /* Now we set up the journal barrier. */
5201                 jbd2_journal_lock_updates(journal);
5202
5203                 /*
5204                  * Don't clear the needs_recovery flag if we failed to
5205                  * flush the journal.
5206                  */
5207                 error = jbd2_journal_flush(journal);
5208                 if (error < 0)
5209                         goto out;
5210
5211                 /* Journal blocked and flushed, clear needs_recovery flag. */
5212                 ext4_clear_feature_journal_needs_recovery(sb);
5213         }
5214
5215         error = ext4_commit_super(sb, 1);
5216 out:
5217         if (journal)
5218                 /* we rely on upper layer to stop further updates */
5219                 jbd2_journal_unlock_updates(journal);
5220         return error;
5221 }
5222
5223 /*
5224  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5225  * flag here, even though the filesystem is not technically dirty yet.
5226  */
5227 static int ext4_unfreeze(struct super_block *sb)
5228 {
5229         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5230                 return 0;
5231
5232         if (EXT4_SB(sb)->s_journal) {
5233                 /* Reset the needs_recovery flag before the fs is unlocked. */
5234                 ext4_set_feature_journal_needs_recovery(sb);
5235         }
5236
5237         ext4_commit_super(sb, 1);
5238         return 0;
5239 }
5240
5241 /*
5242  * Structure to save mount options for ext4_remount's benefit
5243  */
5244 struct ext4_mount_options {
5245         unsigned long s_mount_opt;
5246         unsigned long s_mount_opt2;
5247         kuid_t s_resuid;
5248         kgid_t s_resgid;
5249         unsigned long s_commit_interval;
5250         u32 s_min_batch_time, s_max_batch_time;
5251 #ifdef CONFIG_QUOTA
5252         int s_jquota_fmt;
5253         char *s_qf_names[EXT4_MAXQUOTAS];
5254 #endif
5255 };
5256
5257 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5258 {
5259         struct ext4_super_block *es;
5260         struct ext4_sb_info *sbi = EXT4_SB(sb);
5261         unsigned long old_sb_flags;
5262         struct ext4_mount_options old_opts;
5263         int enable_quota = 0;
5264         ext4_group_t g;
5265         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5266         int err = 0;
5267 #ifdef CONFIG_QUOTA
5268         int i, j;
5269         char *to_free[EXT4_MAXQUOTAS];
5270 #endif
5271         char *orig_data = kstrdup(data, GFP_KERNEL);
5272
5273         if (data && !orig_data)
5274                 return -ENOMEM;
5275
5276         /* Store the original options */
5277         old_sb_flags = sb->s_flags;
5278         old_opts.s_mount_opt = sbi->s_mount_opt;
5279         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5280         old_opts.s_resuid = sbi->s_resuid;
5281         old_opts.s_resgid = sbi->s_resgid;
5282         old_opts.s_commit_interval = sbi->s_commit_interval;
5283         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5284         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5285 #ifdef CONFIG_QUOTA
5286         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5287         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5288                 if (sbi->s_qf_names[i]) {
5289                         char *qf_name = get_qf_name(sb, sbi, i);
5290
5291                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5292                         if (!old_opts.s_qf_names[i]) {
5293                                 for (j = 0; j < i; j++)
5294                                         kfree(old_opts.s_qf_names[j]);
5295                                 kfree(orig_data);
5296                                 return -ENOMEM;
5297                         }
5298                 } else
5299                         old_opts.s_qf_names[i] = NULL;
5300 #endif
5301         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5302                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5303
5304         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5305                 err = -EINVAL;
5306                 goto restore_opts;
5307         }
5308
5309         ext4_clamp_want_extra_isize(sb);
5310
5311         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5312             test_opt(sb, JOURNAL_CHECKSUM)) {
5313                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5314                          "during remount not supported; ignoring");
5315                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5316         }
5317
5318         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5319                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5320                         ext4_msg(sb, KERN_ERR, "can't mount with "
5321                                  "both data=journal and delalloc");
5322                         err = -EINVAL;
5323                         goto restore_opts;
5324                 }
5325                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5326                         ext4_msg(sb, KERN_ERR, "can't mount with "
5327                                  "both data=journal and dioread_nolock");
5328                         err = -EINVAL;
5329                         goto restore_opts;
5330                 }
5331                 if (test_opt(sb, DAX)) {
5332                         ext4_msg(sb, KERN_ERR, "can't mount with "
5333                                  "both data=journal and dax");
5334                         err = -EINVAL;
5335                         goto restore_opts;
5336                 }
5337         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5338                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5339                         ext4_msg(sb, KERN_ERR, "can't mount with "
5340                                 "journal_async_commit in data=ordered mode");
5341                         err = -EINVAL;
5342                         goto restore_opts;
5343                 }
5344         }
5345
5346         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5347                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5348                 err = -EINVAL;
5349                 goto restore_opts;
5350         }
5351
5352         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
5353                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
5354                         "dax flag with busy inodes while remounting");
5355                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
5356         }
5357
5358         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5359                 ext4_abort(sb, "Abort forced by user");
5360
5361         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5362                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5363
5364         es = sbi->s_es;
5365
5366         if (sbi->s_journal) {
5367                 ext4_init_journal_params(sb, sbi->s_journal);
5368                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5369         }
5370
5371         if (*flags & SB_LAZYTIME)
5372                 sb->s_flags |= SB_LAZYTIME;
5373
5374         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5375                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5376                         err = -EROFS;
5377                         goto restore_opts;
5378                 }
5379
5380                 if (*flags & SB_RDONLY) {
5381                         err = sync_filesystem(sb);
5382                         if (err < 0)
5383                                 goto restore_opts;
5384                         err = dquot_suspend(sb, -1);
5385                         if (err < 0)
5386                                 goto restore_opts;
5387
5388                         /*
5389                          * First of all, the unconditional stuff we have to do
5390                          * to disable replay of the journal when we next remount
5391                          */
5392                         sb->s_flags |= SB_RDONLY;
5393
5394                         /*
5395                          * OK, test if we are remounting a valid rw partition
5396                          * readonly, and if so set the rdonly flag and then
5397                          * mark the partition as valid again.
5398                          */
5399                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5400                             (sbi->s_mount_state & EXT4_VALID_FS))
5401                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5402
5403                         if (sbi->s_journal)
5404                                 ext4_mark_recovery_complete(sb, es);
5405                         if (sbi->s_mmp_tsk)
5406                                 kthread_stop(sbi->s_mmp_tsk);
5407                 } else {
5408                         /* Make sure we can mount this feature set readwrite */
5409                         if (ext4_has_feature_readonly(sb) ||
5410                             !ext4_feature_set_ok(sb, 0)) {
5411                                 err = -EROFS;
5412                                 goto restore_opts;
5413                         }
5414                         /*
5415                          * Make sure the group descriptor checksums
5416                          * are sane.  If they aren't, refuse to remount r/w.
5417                          */
5418                         for (g = 0; g < sbi->s_groups_count; g++) {
5419                                 struct ext4_group_desc *gdp =
5420                                         ext4_get_group_desc(sb, g, NULL);
5421
5422                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5423                                         ext4_msg(sb, KERN_ERR,
5424                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5425                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5426                                                le16_to_cpu(gdp->bg_checksum));
5427                                         err = -EFSBADCRC;
5428                                         goto restore_opts;
5429                                 }
5430                         }
5431
5432                         /*
5433                          * If we have an unprocessed orphan list hanging
5434                          * around from a previously readonly bdev mount,
5435                          * require a full umount/remount for now.
5436                          */
5437                         if (es->s_last_orphan) {
5438                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5439                                        "remount RDWR because of unprocessed "
5440                                        "orphan inode list.  Please "
5441                                        "umount/remount instead");
5442                                 err = -EINVAL;
5443                                 goto restore_opts;
5444                         }
5445
5446                         /*
5447                          * Mounting a RDONLY partition read-write, so reread
5448                          * and store the current valid flag.  (It may have
5449                          * been changed by e2fsck since we originally mounted
5450                          * the partition.)
5451                          */
5452                         if (sbi->s_journal)
5453                                 ext4_clear_journal_err(sb, es);
5454                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5455
5456                         err = ext4_setup_super(sb, es, 0);
5457                         if (err)
5458                                 goto restore_opts;
5459
5460                         sb->s_flags &= ~SB_RDONLY;
5461                         if (ext4_has_feature_mmp(sb))
5462                                 if (ext4_multi_mount_protect(sb,
5463                                                 le64_to_cpu(es->s_mmp_block))) {
5464                                         err = -EROFS;
5465                                         goto restore_opts;
5466                                 }
5467                         enable_quota = 1;
5468                 }
5469         }
5470
5471         /*
5472          * Reinitialize lazy itable initialization thread based on
5473          * current settings
5474          */
5475         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5476                 ext4_unregister_li_request(sb);
5477         else {
5478                 ext4_group_t first_not_zeroed;
5479                 first_not_zeroed = ext4_has_uninit_itable(sb);
5480                 ext4_register_li_request(sb, first_not_zeroed);
5481         }
5482
5483         ext4_setup_system_zone(sb);
5484         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5485                 err = ext4_commit_super(sb, 1);
5486                 if (err)
5487                         goto restore_opts;
5488         }
5489
5490 #ifdef CONFIG_QUOTA
5491         /* Release old quota file names */
5492         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5493                 kfree(old_opts.s_qf_names[i]);
5494         if (enable_quota) {
5495                 if (sb_any_quota_suspended(sb))
5496                         dquot_resume(sb, -1);
5497                 else if (ext4_has_feature_quota(sb)) {
5498                         err = ext4_enable_quotas(sb);
5499                         if (err)
5500                                 goto restore_opts;
5501                 }
5502         }
5503 #endif
5504
5505         *flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME);
5506         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5507         kfree(orig_data);
5508         return 0;
5509
5510 restore_opts:
5511         sb->s_flags = old_sb_flags;
5512         sbi->s_mount_opt = old_opts.s_mount_opt;
5513         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5514         sbi->s_resuid = old_opts.s_resuid;
5515         sbi->s_resgid = old_opts.s_resgid;
5516         sbi->s_commit_interval = old_opts.s_commit_interval;
5517         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5518         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5519 #ifdef CONFIG_QUOTA
5520         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5521         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5522                 to_free[i] = get_qf_name(sb, sbi, i);
5523                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
5524         }
5525         synchronize_rcu();
5526         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5527                 kfree(to_free[i]);
5528 #endif
5529         kfree(orig_data);
5530         return err;
5531 }
5532
5533 #ifdef CONFIG_QUOTA
5534 static int ext4_statfs_project(struct super_block *sb,
5535                                kprojid_t projid, struct kstatfs *buf)
5536 {
5537         struct kqid qid;
5538         struct dquot *dquot;
5539         u64 limit;
5540         u64 curblock;
5541
5542         qid = make_kqid_projid(projid);
5543         dquot = dqget(sb, qid);
5544         if (IS_ERR(dquot))
5545                 return PTR_ERR(dquot);
5546         spin_lock(&dquot->dq_dqb_lock);
5547
5548         limit = (dquot->dq_dqb.dqb_bsoftlimit ?
5549                  dquot->dq_dqb.dqb_bsoftlimit :
5550                  dquot->dq_dqb.dqb_bhardlimit) >> sb->s_blocksize_bits;
5551         if (limit && buf->f_blocks > limit) {
5552                 curblock = (dquot->dq_dqb.dqb_curspace +
5553                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5554                 buf->f_blocks = limit;
5555                 buf->f_bfree = buf->f_bavail =
5556                         (buf->f_blocks > curblock) ?
5557                          (buf->f_blocks - curblock) : 0;
5558         }
5559
5560         limit = dquot->dq_dqb.dqb_isoftlimit ?
5561                 dquot->dq_dqb.dqb_isoftlimit :
5562                 dquot->dq_dqb.dqb_ihardlimit;
5563         if (limit && buf->f_files > limit) {
5564                 buf->f_files = limit;
5565                 buf->f_ffree =
5566                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5567                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5568         }
5569
5570         spin_unlock(&dquot->dq_dqb_lock);
5571         dqput(dquot);
5572         return 0;
5573 }
5574 #endif
5575
5576 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5577 {
5578         struct super_block *sb = dentry->d_sb;
5579         struct ext4_sb_info *sbi = EXT4_SB(sb);
5580         struct ext4_super_block *es = sbi->s_es;
5581         ext4_fsblk_t overhead = 0, resv_blocks;
5582         u64 fsid;
5583         s64 bfree;
5584         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5585
5586         if (!test_opt(sb, MINIX_DF))
5587                 overhead = sbi->s_overhead;
5588
5589         buf->f_type = EXT4_SUPER_MAGIC;
5590         buf->f_bsize = sb->s_blocksize;
5591         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5592         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5593                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5594         /* prevent underflow in case that few free space is available */
5595         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5596         buf->f_bavail = buf->f_bfree -
5597                         (ext4_r_blocks_count(es) + resv_blocks);
5598         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5599                 buf->f_bavail = 0;
5600         buf->f_files = le32_to_cpu(es->s_inodes_count);
5601         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5602         buf->f_namelen = EXT4_NAME_LEN;
5603         fsid = le64_to_cpup((void *)es->s_uuid) ^
5604                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5605         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5606         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5607
5608 #ifdef CONFIG_QUOTA
5609         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5610             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5611                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5612 #endif
5613         return 0;
5614 }
5615
5616
5617 #ifdef CONFIG_QUOTA
5618
5619 /*
5620  * Helper functions so that transaction is started before we acquire dqio_sem
5621  * to keep correct lock ordering of transaction > dqio_sem
5622  */
5623 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5624 {
5625         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5626 }
5627
5628 static int ext4_write_dquot(struct dquot *dquot)
5629 {
5630         int ret, err;
5631         handle_t *handle;
5632         struct inode *inode;
5633
5634         inode = dquot_to_inode(dquot);
5635         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5636                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5637         if (IS_ERR(handle))
5638                 return PTR_ERR(handle);
5639         ret = dquot_commit(dquot);
5640         err = ext4_journal_stop(handle);
5641         if (!ret)
5642                 ret = err;
5643         return ret;
5644 }
5645
5646 static int ext4_acquire_dquot(struct dquot *dquot)
5647 {
5648         int ret, err;
5649         handle_t *handle;
5650
5651         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5652                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5653         if (IS_ERR(handle))
5654                 return PTR_ERR(handle);
5655         ret = dquot_acquire(dquot);
5656         err = ext4_journal_stop(handle);
5657         if (!ret)
5658                 ret = err;
5659         return ret;
5660 }
5661
5662 static int ext4_release_dquot(struct dquot *dquot)
5663 {
5664         int ret, err;
5665         handle_t *handle;
5666
5667         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5668                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5669         if (IS_ERR(handle)) {
5670                 /* Release dquot anyway to avoid endless cycle in dqput() */
5671                 dquot_release(dquot);
5672                 return PTR_ERR(handle);
5673         }
5674         ret = dquot_release(dquot);
5675         err = ext4_journal_stop(handle);
5676         if (!ret)
5677                 ret = err;
5678         return ret;
5679 }
5680
5681 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5682 {
5683         struct super_block *sb = dquot->dq_sb;
5684         struct ext4_sb_info *sbi = EXT4_SB(sb);
5685
5686         /* Are we journaling quotas? */
5687         if (ext4_has_feature_quota(sb) ||
5688             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5689                 dquot_mark_dquot_dirty(dquot);
5690                 return ext4_write_dquot(dquot);
5691         } else {
5692                 return dquot_mark_dquot_dirty(dquot);
5693         }
5694 }
5695
5696 static int ext4_write_info(struct super_block *sb, int type)
5697 {
5698         int ret, err;
5699         handle_t *handle;
5700
5701         /* Data block + inode block */
5702         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5703         if (IS_ERR(handle))
5704                 return PTR_ERR(handle);
5705         ret = dquot_commit_info(sb, type);
5706         err = ext4_journal_stop(handle);
5707         if (!ret)
5708                 ret = err;
5709         return ret;
5710 }
5711
5712 /*
5713  * Turn on quotas during mount time - we need to find
5714  * the quota file and such...
5715  */
5716 static int ext4_quota_on_mount(struct super_block *sb, int type)
5717 {
5718         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
5719                                         EXT4_SB(sb)->s_jquota_fmt, type);
5720 }
5721
5722 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5723 {
5724         struct ext4_inode_info *ei = EXT4_I(inode);
5725
5726         /* The first argument of lockdep_set_subclass has to be
5727          * *exactly* the same as the argument to init_rwsem() --- in
5728          * this case, in init_once() --- or lockdep gets unhappy
5729          * because the name of the lock is set using the
5730          * stringification of the argument to init_rwsem().
5731          */
5732         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
5733         lockdep_set_subclass(&ei->i_data_sem, subclass);
5734 }
5735
5736 /*
5737  * Standard function to be called on quota_on
5738  */
5739 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5740                          const struct path *path)
5741 {
5742         int err;
5743
5744         if (!test_opt(sb, QUOTA))
5745                 return -EINVAL;
5746
5747         /* Quotafile not on the same filesystem? */
5748         if (path->dentry->d_sb != sb)
5749                 return -EXDEV;
5750         /* Journaling quota? */
5751         if (EXT4_SB(sb)->s_qf_names[type]) {
5752                 /* Quotafile not in fs root? */
5753                 if (path->dentry->d_parent != sb->s_root)
5754                         ext4_msg(sb, KERN_WARNING,
5755                                 "Quota file not on filesystem root. "
5756                                 "Journaled quota will not work");
5757                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5758         } else {
5759                 /*
5760                  * Clear the flag just in case mount options changed since
5761                  * last time.
5762                  */
5763                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5764         }
5765
5766         /*
5767          * When we journal data on quota file, we have to flush journal to see
5768          * all updates to the file when we bypass pagecache...
5769          */
5770         if (EXT4_SB(sb)->s_journal &&
5771             ext4_should_journal_data(d_inode(path->dentry))) {
5772                 /*
5773                  * We don't need to lock updates but journal_flush() could
5774                  * otherwise be livelocked...
5775                  */
5776                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5777                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5778                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5779                 if (err)
5780                         return err;
5781         }
5782
5783         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5784         err = dquot_quota_on(sb, type, format_id, path);
5785         if (err) {
5786                 lockdep_set_quota_inode(path->dentry->d_inode,
5787                                              I_DATA_SEM_NORMAL);
5788         } else {
5789                 struct inode *inode = d_inode(path->dentry);
5790                 handle_t *handle;
5791
5792                 /*
5793                  * Set inode flags to prevent userspace from messing with quota
5794                  * files. If this fails, we return success anyway since quotas
5795                  * are already enabled and this is not a hard failure.
5796                  */
5797                 inode_lock(inode);
5798                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5799                 if (IS_ERR(handle))
5800                         goto unlock_inode;
5801                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5802                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5803                                 S_NOATIME | S_IMMUTABLE);
5804                 ext4_mark_inode_dirty(handle, inode);
5805                 ext4_journal_stop(handle);
5806         unlock_inode:
5807                 inode_unlock(inode);
5808         }
5809         return err;
5810 }
5811
5812 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5813                              unsigned int flags)
5814 {
5815         int err;
5816         struct inode *qf_inode;
5817         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5818                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5819                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5820                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5821         };
5822
5823         BUG_ON(!ext4_has_feature_quota(sb));
5824
5825         if (!qf_inums[type])
5826                 return -EPERM;
5827
5828         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
5829         if (IS_ERR(qf_inode)) {
5830                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5831                 return PTR_ERR(qf_inode);
5832         }
5833
5834         /* Don't account quota for quota files to avoid recursion */
5835         qf_inode->i_flags |= S_NOQUOTA;
5836         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5837         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
5838         if (err)
5839                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5840         iput(qf_inode);
5841
5842         return err;
5843 }
5844
5845 /* Enable usage tracking for all quota types. */
5846 static int ext4_enable_quotas(struct super_block *sb)
5847 {
5848         int type, err = 0;
5849         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5850                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5851                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5852                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5853         };
5854         bool quota_mopt[EXT4_MAXQUOTAS] = {
5855                 test_opt(sb, USRQUOTA),
5856                 test_opt(sb, GRPQUOTA),
5857                 test_opt(sb, PRJQUOTA),
5858         };
5859
5860         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
5861         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5862                 if (qf_inums[type]) {
5863                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5864                                 DQUOT_USAGE_ENABLED |
5865                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5866                         if (err) {
5867                                 ext4_warning(sb,
5868                                         "Failed to enable quota tracking "
5869                                         "(type=%d, err=%d). Please run "
5870                                         "e2fsck to fix.", type, err);
5871                                 for (type--; type >= 0; type--)
5872                                         dquot_quota_off(sb, type);
5873
5874                                 return err;
5875                         }
5876                 }
5877         }
5878         return 0;
5879 }
5880
5881 static int ext4_quota_off(struct super_block *sb, int type)
5882 {
5883         struct inode *inode = sb_dqopt(sb)->files[type];
5884         handle_t *handle;
5885         int err;
5886
5887         /* Force all delayed allocation blocks to be allocated.
5888          * Caller already holds s_umount sem */
5889         if (test_opt(sb, DELALLOC))
5890                 sync_filesystem(sb);
5891
5892         if (!inode || !igrab(inode))
5893                 goto out;
5894
5895         err = dquot_quota_off(sb, type);
5896         if (err || ext4_has_feature_quota(sb))
5897                 goto out_put;
5898
5899         inode_lock(inode);
5900         /*
5901          * Update modification times of quota files when userspace can
5902          * start looking at them. If we fail, we return success anyway since
5903          * this is not a hard failure and quotas are already disabled.
5904          */
5905         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5906         if (IS_ERR(handle))
5907                 goto out_unlock;
5908         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
5909         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
5910         inode->i_mtime = inode->i_ctime = current_time(inode);
5911         ext4_mark_inode_dirty(handle, inode);
5912         ext4_journal_stop(handle);
5913 out_unlock:
5914         inode_unlock(inode);
5915 out_put:
5916         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
5917         iput(inode);
5918         return err;
5919 out:
5920         return dquot_quota_off(sb, type);
5921 }
5922
5923 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5924  * acquiring the locks... As quota files are never truncated and quota code
5925  * itself serializes the operations (and no one else should touch the files)
5926  * we don't have to be afraid of races */
5927 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5928                                size_t len, loff_t off)
5929 {
5930         struct inode *inode = sb_dqopt(sb)->files[type];
5931         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5932         int offset = off & (sb->s_blocksize - 1);
5933         int tocopy;
5934         size_t toread;
5935         struct buffer_head *bh;
5936         loff_t i_size = i_size_read(inode);
5937
5938         if (off > i_size)
5939                 return 0;
5940         if (off+len > i_size)
5941                 len = i_size-off;
5942         toread = len;
5943         while (toread > 0) {
5944                 tocopy = sb->s_blocksize - offset < toread ?
5945                                 sb->s_blocksize - offset : toread;
5946                 bh = ext4_bread(NULL, inode, blk, 0);
5947                 if (IS_ERR(bh))
5948                         return PTR_ERR(bh);
5949                 if (!bh)        /* A hole? */
5950                         memset(data, 0, tocopy);
5951                 else
5952                         memcpy(data, bh->b_data+offset, tocopy);
5953                 brelse(bh);
5954                 offset = 0;
5955                 toread -= tocopy;
5956                 data += tocopy;
5957                 blk++;
5958         }
5959         return len;
5960 }
5961
5962 /* Write to quotafile (we know the transaction is already started and has
5963  * enough credits) */
5964 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5965                                 const char *data, size_t len, loff_t off)
5966 {
5967         struct inode *inode = sb_dqopt(sb)->files[type];
5968         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5969         int err, offset = off & (sb->s_blocksize - 1);
5970         int retries = 0;
5971         struct buffer_head *bh;
5972         handle_t *handle = journal_current_handle();
5973
5974         if (EXT4_SB(sb)->s_journal && !handle) {
5975                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5976                         " cancelled because transaction is not started",
5977                         (unsigned long long)off, (unsigned long long)len);
5978                 return -EIO;
5979         }
5980         /*
5981          * Since we account only one data block in transaction credits,
5982          * then it is impossible to cross a block boundary.
5983          */
5984         if (sb->s_blocksize - offset < len) {
5985                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5986                         " cancelled because not block aligned",
5987                         (unsigned long long)off, (unsigned long long)len);
5988                 return -EIO;
5989         }
5990
5991         do {
5992                 bh = ext4_bread(handle, inode, blk,
5993                                 EXT4_GET_BLOCKS_CREATE |
5994                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
5995         } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
5996                  ext4_should_retry_alloc(inode->i_sb, &retries));
5997         if (IS_ERR(bh))
5998                 return PTR_ERR(bh);
5999         if (!bh)
6000                 goto out;
6001         BUFFER_TRACE(bh, "get write access");
6002         err = ext4_journal_get_write_access(handle, bh);
6003         if (err) {
6004                 brelse(bh);
6005                 return err;
6006         }
6007         lock_buffer(bh);
6008         memcpy(bh->b_data+offset, data, len);
6009         flush_dcache_page(bh->b_page);
6010         unlock_buffer(bh);
6011         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6012         brelse(bh);
6013 out:
6014         if (inode->i_size < off + len) {
6015                 i_size_write(inode, off + len);
6016                 EXT4_I(inode)->i_disksize = inode->i_size;
6017                 ext4_mark_inode_dirty(handle, inode);
6018         }
6019         return len;
6020 }
6021 #endif
6022
6023 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6024                        const char *dev_name, void *data)
6025 {
6026         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6027 }
6028
6029 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6030 static inline void register_as_ext2(void)
6031 {
6032         int err = register_filesystem(&ext2_fs_type);
6033         if (err)
6034                 printk(KERN_WARNING
6035                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6036 }
6037
6038 static inline void unregister_as_ext2(void)
6039 {
6040         unregister_filesystem(&ext2_fs_type);
6041 }
6042
6043 static inline int ext2_feature_set_ok(struct super_block *sb)
6044 {
6045         if (ext4_has_unknown_ext2_incompat_features(sb))
6046                 return 0;
6047         if (sb_rdonly(sb))
6048                 return 1;
6049         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6050                 return 0;
6051         return 1;
6052 }
6053 #else
6054 static inline void register_as_ext2(void) { }
6055 static inline void unregister_as_ext2(void) { }
6056 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6057 #endif
6058
6059 static inline void register_as_ext3(void)
6060 {
6061         int err = register_filesystem(&ext3_fs_type);
6062         if (err)
6063                 printk(KERN_WARNING
6064                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6065 }
6066
6067 static inline void unregister_as_ext3(void)
6068 {
6069         unregister_filesystem(&ext3_fs_type);
6070 }
6071
6072 static inline int ext3_feature_set_ok(struct super_block *sb)
6073 {
6074         if (ext4_has_unknown_ext3_incompat_features(sb))
6075                 return 0;
6076         if (!ext4_has_feature_journal(sb))
6077                 return 0;
6078         if (sb_rdonly(sb))
6079                 return 1;
6080         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6081                 return 0;
6082         return 1;
6083 }
6084
6085 static struct file_system_type ext4_fs_type = {
6086         .owner          = THIS_MODULE,
6087         .name           = "ext4",
6088         .mount          = ext4_mount,
6089         .kill_sb        = kill_block_super,
6090         .fs_flags       = FS_REQUIRES_DEV,
6091 };
6092 MODULE_ALIAS_FS("ext4");
6093
6094 /* Shared across all ext4 file systems */
6095 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6096
6097 static int __init ext4_init_fs(void)
6098 {
6099         int i, err;
6100
6101         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6102         ext4_li_info = NULL;
6103         mutex_init(&ext4_li_mtx);
6104
6105         /* Build-time check for flags consistency */
6106         ext4_check_flag_values();
6107
6108         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6109                 init_waitqueue_head(&ext4__ioend_wq[i]);
6110
6111         err = ext4_init_es();
6112         if (err)
6113                 return err;
6114
6115         err = ext4_init_pending();
6116         if (err)
6117                 goto out7;
6118
6119         err = ext4_init_post_read_processing();
6120         if (err)
6121                 goto out6;
6122
6123         err = ext4_init_pageio();
6124         if (err)
6125                 goto out5;
6126
6127         err = ext4_init_system_zone();
6128         if (err)
6129                 goto out4;
6130
6131         err = ext4_init_sysfs();
6132         if (err)
6133                 goto out3;
6134
6135         err = ext4_init_mballoc();
6136         if (err)
6137                 goto out2;
6138         err = init_inodecache();
6139         if (err)
6140                 goto out1;
6141         register_as_ext3();
6142         register_as_ext2();
6143         err = register_filesystem(&ext4_fs_type);
6144         if (err)
6145                 goto out;
6146
6147         return 0;
6148 out:
6149         unregister_as_ext2();
6150         unregister_as_ext3();
6151         destroy_inodecache();
6152 out1:
6153         ext4_exit_mballoc();
6154 out2:
6155         ext4_exit_sysfs();
6156 out3:
6157         ext4_exit_system_zone();
6158 out4:
6159         ext4_exit_pageio();
6160 out5:
6161         ext4_exit_post_read_processing();
6162 out6:
6163         ext4_exit_pending();
6164 out7:
6165         ext4_exit_es();
6166
6167         return err;
6168 }
6169
6170 static void __exit ext4_exit_fs(void)
6171 {
6172         ext4_destroy_lazyinit_thread();
6173         unregister_as_ext2();
6174         unregister_as_ext3();
6175         unregister_filesystem(&ext4_fs_type);
6176         destroy_inodecache();
6177         ext4_exit_mballoc();
6178         ext4_exit_sysfs();
6179         ext4_exit_system_zone();
6180         ext4_exit_pageio();
6181         ext4_exit_post_read_processing();
6182         ext4_exit_es();
6183         ext4_exit_pending();
6184 }
6185
6186 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6187 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6188 MODULE_LICENSE("GPL");
6189 MODULE_SOFTDEP("pre: crc32c");
6190 module_init(ext4_init_fs)
6191 module_exit(ext4_exit_fs)