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         dquot_drop(inode);
1176         ext4_discard_preallocations(inode);
1177         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
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 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid);
1392
1393 static struct dquot **ext4_get_dquots(struct inode *inode)
1394 {
1395         return EXT4_I(inode)->i_dquot;
1396 }
1397
1398 static const struct dquot_operations ext4_quota_operations = {
1399         .get_reserved_space     = ext4_get_reserved_space,
1400         .write_dquot            = ext4_write_dquot,
1401         .acquire_dquot          = ext4_acquire_dquot,
1402         .release_dquot          = ext4_release_dquot,
1403         .mark_dirty             = ext4_mark_dquot_dirty,
1404         .write_info             = ext4_write_info,
1405         .alloc_dquot            = dquot_alloc,
1406         .destroy_dquot          = dquot_destroy,
1407         .get_projid             = ext4_get_projid,
1408         .get_inode_usage        = ext4_get_inode_usage,
1409         .get_next_id            = ext4_get_next_id,
1410 };
1411
1412 static const struct quotactl_ops ext4_qctl_operations = {
1413         .quota_on       = ext4_quota_on,
1414         .quota_off      = ext4_quota_off,
1415         .quota_sync     = dquot_quota_sync,
1416         .get_state      = dquot_get_state,
1417         .set_info       = dquot_set_dqinfo,
1418         .get_dqblk      = dquot_get_dqblk,
1419         .set_dqblk      = dquot_set_dqblk,
1420         .get_nextdqblk  = dquot_get_next_dqblk,
1421 };
1422 #endif
1423
1424 static const struct super_operations ext4_sops = {
1425         .alloc_inode    = ext4_alloc_inode,
1426         .free_inode     = ext4_free_in_core_inode,
1427         .destroy_inode  = ext4_destroy_inode,
1428         .write_inode    = ext4_write_inode,
1429         .dirty_inode    = ext4_dirty_inode,
1430         .drop_inode     = ext4_drop_inode,
1431         .evict_inode    = ext4_evict_inode,
1432         .put_super      = ext4_put_super,
1433         .sync_fs        = ext4_sync_fs,
1434         .freeze_fs      = ext4_freeze,
1435         .unfreeze_fs    = ext4_unfreeze,
1436         .statfs         = ext4_statfs,
1437         .remount_fs     = ext4_remount,
1438         .show_options   = ext4_show_options,
1439 #ifdef CONFIG_QUOTA
1440         .quota_read     = ext4_quota_read,
1441         .quota_write    = ext4_quota_write,
1442         .get_dquots     = ext4_get_dquots,
1443 #endif
1444         .bdev_try_to_free_page = bdev_try_to_free_page,
1445 };
1446
1447 static const struct export_operations ext4_export_ops = {
1448         .fh_to_dentry = ext4_fh_to_dentry,
1449         .fh_to_parent = ext4_fh_to_parent,
1450         .get_parent = ext4_get_parent,
1451         .commit_metadata = ext4_nfs_commit_metadata,
1452 };
1453
1454 enum {
1455         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1456         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1457         Opt_nouid32, Opt_debug, Opt_removed,
1458         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1459         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1460         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1461         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1462         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1463         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1464         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1465         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1466         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1467         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1468         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1469         Opt_nowarn_on_error, Opt_mblk_io_submit,
1470         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1471         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1472         Opt_inode_readahead_blks, Opt_journal_ioprio,
1473         Opt_dioread_nolock, Opt_dioread_lock,
1474         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1475         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1476 };
1477
1478 static const match_table_t tokens = {
1479         {Opt_bsd_df, "bsddf"},
1480         {Opt_minix_df, "minixdf"},
1481         {Opt_grpid, "grpid"},
1482         {Opt_grpid, "bsdgroups"},
1483         {Opt_nogrpid, "nogrpid"},
1484         {Opt_nogrpid, "sysvgroups"},
1485         {Opt_resgid, "resgid=%u"},
1486         {Opt_resuid, "resuid=%u"},
1487         {Opt_sb, "sb=%u"},
1488         {Opt_err_cont, "errors=continue"},
1489         {Opt_err_panic, "errors=panic"},
1490         {Opt_err_ro, "errors=remount-ro"},
1491         {Opt_nouid32, "nouid32"},
1492         {Opt_debug, "debug"},
1493         {Opt_removed, "oldalloc"},
1494         {Opt_removed, "orlov"},
1495         {Opt_user_xattr, "user_xattr"},
1496         {Opt_nouser_xattr, "nouser_xattr"},
1497         {Opt_acl, "acl"},
1498         {Opt_noacl, "noacl"},
1499         {Opt_noload, "norecovery"},
1500         {Opt_noload, "noload"},
1501         {Opt_removed, "nobh"},
1502         {Opt_removed, "bh"},
1503         {Opt_commit, "commit=%u"},
1504         {Opt_min_batch_time, "min_batch_time=%u"},
1505         {Opt_max_batch_time, "max_batch_time=%u"},
1506         {Opt_journal_dev, "journal_dev=%u"},
1507         {Opt_journal_path, "journal_path=%s"},
1508         {Opt_journal_checksum, "journal_checksum"},
1509         {Opt_nojournal_checksum, "nojournal_checksum"},
1510         {Opt_journal_async_commit, "journal_async_commit"},
1511         {Opt_abort, "abort"},
1512         {Opt_data_journal, "data=journal"},
1513         {Opt_data_ordered, "data=ordered"},
1514         {Opt_data_writeback, "data=writeback"},
1515         {Opt_data_err_abort, "data_err=abort"},
1516         {Opt_data_err_ignore, "data_err=ignore"},
1517         {Opt_offusrjquota, "usrjquota="},
1518         {Opt_usrjquota, "usrjquota=%s"},
1519         {Opt_offgrpjquota, "grpjquota="},
1520         {Opt_grpjquota, "grpjquota=%s"},
1521         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1522         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1523         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1524         {Opt_grpquota, "grpquota"},
1525         {Opt_noquota, "noquota"},
1526         {Opt_quota, "quota"},
1527         {Opt_usrquota, "usrquota"},
1528         {Opt_prjquota, "prjquota"},
1529         {Opt_barrier, "barrier=%u"},
1530         {Opt_barrier, "barrier"},
1531         {Opt_nobarrier, "nobarrier"},
1532         {Opt_i_version, "i_version"},
1533         {Opt_dax, "dax"},
1534         {Opt_stripe, "stripe=%u"},
1535         {Opt_delalloc, "delalloc"},
1536         {Opt_warn_on_error, "warn_on_error"},
1537         {Opt_nowarn_on_error, "nowarn_on_error"},
1538         {Opt_lazytime, "lazytime"},
1539         {Opt_nolazytime, "nolazytime"},
1540         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1541         {Opt_nodelalloc, "nodelalloc"},
1542         {Opt_removed, "mblk_io_submit"},
1543         {Opt_removed, "nomblk_io_submit"},
1544         {Opt_block_validity, "block_validity"},
1545         {Opt_noblock_validity, "noblock_validity"},
1546         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1547         {Opt_journal_ioprio, "journal_ioprio=%u"},
1548         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1549         {Opt_auto_da_alloc, "auto_da_alloc"},
1550         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1551         {Opt_dioread_nolock, "dioread_nolock"},
1552         {Opt_dioread_lock, "dioread_lock"},
1553         {Opt_discard, "discard"},
1554         {Opt_nodiscard, "nodiscard"},
1555         {Opt_init_itable, "init_itable=%u"},
1556         {Opt_init_itable, "init_itable"},
1557         {Opt_noinit_itable, "noinit_itable"},
1558         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1559         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1560         {Opt_nombcache, "nombcache"},
1561         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1562         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1563         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1564         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1565         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1566         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1567         {Opt_err, NULL},
1568 };
1569
1570 static ext4_fsblk_t get_sb_block(void **data)
1571 {
1572         ext4_fsblk_t    sb_block;
1573         char            *options = (char *) *data;
1574
1575         if (!options || strncmp(options, "sb=", 3) != 0)
1576                 return 1;       /* Default location */
1577
1578         options += 3;
1579         /* TODO: use simple_strtoll with >32bit ext4 */
1580         sb_block = simple_strtoul(options, &options, 0);
1581         if (*options && *options != ',') {
1582                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1583                        (char *) *data);
1584                 return 1;
1585         }
1586         if (*options == ',')
1587                 options++;
1588         *data = (void *) options;
1589
1590         return sb_block;
1591 }
1592
1593 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1594 static const char deprecated_msg[] =
1595         "Mount option \"%s\" will be removed by %s\n"
1596         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1597
1598 #ifdef CONFIG_QUOTA
1599 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1600 {
1601         struct ext4_sb_info *sbi = EXT4_SB(sb);
1602         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1603         int ret = -1;
1604
1605         if (sb_any_quota_loaded(sb) && !old_qname) {
1606                 ext4_msg(sb, KERN_ERR,
1607                         "Cannot change journaled "
1608                         "quota options when quota turned on");
1609                 return -1;
1610         }
1611         if (ext4_has_feature_quota(sb)) {
1612                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1613                          "ignored when QUOTA feature is enabled");
1614                 return 1;
1615         }
1616         qname = match_strdup(args);
1617         if (!qname) {
1618                 ext4_msg(sb, KERN_ERR,
1619                         "Not enough memory for storing quotafile name");
1620                 return -1;
1621         }
1622         if (old_qname) {
1623                 if (strcmp(old_qname, qname) == 0)
1624                         ret = 1;
1625                 else
1626                         ext4_msg(sb, KERN_ERR,
1627                                  "%s quota file already specified",
1628                                  QTYPE2NAME(qtype));
1629                 goto errout;
1630         }
1631         if (strchr(qname, '/')) {
1632                 ext4_msg(sb, KERN_ERR,
1633                         "quotafile must be on filesystem root");
1634                 goto errout;
1635         }
1636         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1637         set_opt(sb, QUOTA);
1638         return 1;
1639 errout:
1640         kfree(qname);
1641         return ret;
1642 }
1643
1644 static int clear_qf_name(struct super_block *sb, int qtype)
1645 {
1646
1647         struct ext4_sb_info *sbi = EXT4_SB(sb);
1648         char *old_qname = get_qf_name(sb, sbi, qtype);
1649
1650         if (sb_any_quota_loaded(sb) && old_qname) {
1651                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1652                         " when quota turned on");
1653                 return -1;
1654         }
1655         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1656         synchronize_rcu();
1657         kfree(old_qname);
1658         return 1;
1659 }
1660 #endif
1661
1662 #define MOPT_SET        0x0001
1663 #define MOPT_CLEAR      0x0002
1664 #define MOPT_NOSUPPORT  0x0004
1665 #define MOPT_EXPLICIT   0x0008
1666 #define MOPT_CLEAR_ERR  0x0010
1667 #define MOPT_GTE0       0x0020
1668 #ifdef CONFIG_QUOTA
1669 #define MOPT_Q          0
1670 #define MOPT_QFMT       0x0040
1671 #else
1672 #define MOPT_Q          MOPT_NOSUPPORT
1673 #define MOPT_QFMT       MOPT_NOSUPPORT
1674 #endif
1675 #define MOPT_DATAJ      0x0080
1676 #define MOPT_NO_EXT2    0x0100
1677 #define MOPT_NO_EXT3    0x0200
1678 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1679 #define MOPT_STRING     0x0400
1680
1681 static const struct mount_opts {
1682         int     token;
1683         int     mount_opt;
1684         int     flags;
1685 } ext4_mount_opts[] = {
1686         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1687         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1688         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1689         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1690         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1691         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1692         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1693          MOPT_EXT4_ONLY | MOPT_SET},
1694         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1695          MOPT_EXT4_ONLY | MOPT_CLEAR},
1696         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1697         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1698         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1699          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1700         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1701          MOPT_EXT4_ONLY | MOPT_CLEAR},
1702         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1703         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1704         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1705          MOPT_EXT4_ONLY | MOPT_CLEAR},
1706         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1707          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1708         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1709                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1710          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1711         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1712         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1713         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1714         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1715         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1716          MOPT_NO_EXT2},
1717         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1718          MOPT_NO_EXT2},
1719         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1720         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1721         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1722         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1723         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1724         {Opt_commit, 0, MOPT_GTE0},
1725         {Opt_max_batch_time, 0, MOPT_GTE0},
1726         {Opt_min_batch_time, 0, MOPT_GTE0},
1727         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1728         {Opt_init_itable, 0, MOPT_GTE0},
1729         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1730         {Opt_stripe, 0, MOPT_GTE0},
1731         {Opt_resuid, 0, MOPT_GTE0},
1732         {Opt_resgid, 0, MOPT_GTE0},
1733         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1734         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1735         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1736         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1737         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1738         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1739          MOPT_NO_EXT2 | MOPT_DATAJ},
1740         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1741         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1742 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1743         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1744         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1745 #else
1746         {Opt_acl, 0, MOPT_NOSUPPORT},
1747         {Opt_noacl, 0, MOPT_NOSUPPORT},
1748 #endif
1749         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1750         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1751         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1752         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1753         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1754                                                         MOPT_SET | MOPT_Q},
1755         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1756                                                         MOPT_SET | MOPT_Q},
1757         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1758                                                         MOPT_SET | MOPT_Q},
1759         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1760                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1761                                                         MOPT_CLEAR | MOPT_Q},
1762         {Opt_usrjquota, 0, MOPT_Q},
1763         {Opt_grpjquota, 0, MOPT_Q},
1764         {Opt_offusrjquota, 0, MOPT_Q},
1765         {Opt_offgrpjquota, 0, MOPT_Q},
1766         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1767         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1768         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1769         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1770         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1771         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1772         {Opt_err, 0, 0}
1773 };
1774
1775 #ifdef CONFIG_UNICODE
1776 static const struct ext4_sb_encodings {
1777         __u16 magic;
1778         char *name;
1779         char *version;
1780 } ext4_sb_encoding_map[] = {
1781         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
1782 };
1783
1784 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
1785                                  const struct ext4_sb_encodings **encoding,
1786                                  __u16 *flags)
1787 {
1788         __u16 magic = le16_to_cpu(es->s_encoding);
1789         int i;
1790
1791         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1792                 if (magic == ext4_sb_encoding_map[i].magic)
1793                         break;
1794
1795         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
1796                 return -EINVAL;
1797
1798         *encoding = &ext4_sb_encoding_map[i];
1799         *flags = le16_to_cpu(es->s_encoding_flags);
1800
1801         return 0;
1802 }
1803 #endif
1804
1805 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1806                             substring_t *args, unsigned long *journal_devnum,
1807                             unsigned int *journal_ioprio, int is_remount)
1808 {
1809         struct ext4_sb_info *sbi = EXT4_SB(sb);
1810         const struct mount_opts *m;
1811         kuid_t uid;
1812         kgid_t gid;
1813         int arg = 0;
1814
1815 #ifdef CONFIG_QUOTA
1816         if (token == Opt_usrjquota)
1817                 return set_qf_name(sb, USRQUOTA, &args[0]);
1818         else if (token == Opt_grpjquota)
1819                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1820         else if (token == Opt_offusrjquota)
1821                 return clear_qf_name(sb, USRQUOTA);
1822         else if (token == Opt_offgrpjquota)
1823                 return clear_qf_name(sb, GRPQUOTA);
1824 #endif
1825         switch (token) {
1826         case Opt_noacl:
1827         case Opt_nouser_xattr:
1828                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1829                 break;
1830         case Opt_sb:
1831                 return 1;       /* handled by get_sb_block() */
1832         case Opt_removed:
1833                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1834                 return 1;
1835         case Opt_abort:
1836                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1837                 return 1;
1838         case Opt_i_version:
1839                 sb->s_flags |= SB_I_VERSION;
1840                 return 1;
1841         case Opt_lazytime:
1842                 sb->s_flags |= SB_LAZYTIME;
1843                 return 1;
1844         case Opt_nolazytime:
1845                 sb->s_flags &= ~SB_LAZYTIME;
1846                 return 1;
1847         }
1848
1849         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1850                 if (token == m->token)
1851                         break;
1852
1853         if (m->token == Opt_err) {
1854                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1855                          "or missing value", opt);
1856                 return -1;
1857         }
1858
1859         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1860                 ext4_msg(sb, KERN_ERR,
1861                          "Mount option \"%s\" incompatible with ext2", opt);
1862                 return -1;
1863         }
1864         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1865                 ext4_msg(sb, KERN_ERR,
1866                          "Mount option \"%s\" incompatible with ext3", opt);
1867                 return -1;
1868         }
1869
1870         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1871                 return -1;
1872         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1873                 return -1;
1874         if (m->flags & MOPT_EXPLICIT) {
1875                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1876                         set_opt2(sb, EXPLICIT_DELALLOC);
1877                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1878                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1879                 } else
1880                         return -1;
1881         }
1882         if (m->flags & MOPT_CLEAR_ERR)
1883                 clear_opt(sb, ERRORS_MASK);
1884         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1885                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1886                          "options when quota turned on");
1887                 return -1;
1888         }
1889
1890         if (m->flags & MOPT_NOSUPPORT) {
1891                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1892         } else if (token == Opt_commit) {
1893                 if (arg == 0)
1894                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1895                 else if (arg > INT_MAX / HZ) {
1896                         ext4_msg(sb, KERN_ERR,
1897                                  "Invalid commit interval %d, "
1898                                  "must be smaller than %d",
1899                                  arg, INT_MAX / HZ);
1900                         return -1;
1901                 }
1902                 sbi->s_commit_interval = HZ * arg;
1903         } else if (token == Opt_debug_want_extra_isize) {
1904                 sbi->s_want_extra_isize = arg;
1905         } else if (token == Opt_max_batch_time) {
1906                 sbi->s_max_batch_time = arg;
1907         } else if (token == Opt_min_batch_time) {
1908                 sbi->s_min_batch_time = arg;
1909         } else if (token == Opt_inode_readahead_blks) {
1910                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1911                         ext4_msg(sb, KERN_ERR,
1912                                  "EXT4-fs: inode_readahead_blks must be "
1913                                  "0 or a power of 2 smaller than 2^31");
1914                         return -1;
1915                 }
1916                 sbi->s_inode_readahead_blks = arg;
1917         } else if (token == Opt_init_itable) {
1918                 set_opt(sb, INIT_INODE_TABLE);
1919                 if (!args->from)
1920                         arg = EXT4_DEF_LI_WAIT_MULT;
1921                 sbi->s_li_wait_mult = arg;
1922         } else if (token == Opt_max_dir_size_kb) {
1923                 sbi->s_max_dir_size_kb = arg;
1924         } else if (token == Opt_stripe) {
1925                 sbi->s_stripe = arg;
1926         } else if (token == Opt_resuid) {
1927                 uid = make_kuid(current_user_ns(), arg);
1928                 if (!uid_valid(uid)) {
1929                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1930                         return -1;
1931                 }
1932                 sbi->s_resuid = uid;
1933         } else if (token == Opt_resgid) {
1934                 gid = make_kgid(current_user_ns(), arg);
1935                 if (!gid_valid(gid)) {
1936                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1937                         return -1;
1938                 }
1939                 sbi->s_resgid = gid;
1940         } else if (token == Opt_journal_dev) {
1941                 if (is_remount) {
1942                         ext4_msg(sb, KERN_ERR,
1943                                  "Cannot specify journal on remount");
1944                         return -1;
1945                 }
1946                 *journal_devnum = arg;
1947         } else if (token == Opt_journal_path) {
1948                 char *journal_path;
1949                 struct inode *journal_inode;
1950                 struct path path;
1951                 int error;
1952
1953                 if (is_remount) {
1954                         ext4_msg(sb, KERN_ERR,
1955                                  "Cannot specify journal on remount");
1956                         return -1;
1957                 }
1958                 journal_path = match_strdup(&args[0]);
1959                 if (!journal_path) {
1960                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1961                                 "journal device string");
1962                         return -1;
1963                 }
1964
1965                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1966                 if (error) {
1967                         ext4_msg(sb, KERN_ERR, "error: could not find "
1968                                 "journal device path: error %d", error);
1969                         kfree(journal_path);
1970                         return -1;
1971                 }
1972
1973                 journal_inode = d_inode(path.dentry);
1974                 if (!S_ISBLK(journal_inode->i_mode)) {
1975                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1976                                 "is not a block device", journal_path);
1977                         path_put(&path);
1978                         kfree(journal_path);
1979                         return -1;
1980                 }
1981
1982                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1983                 path_put(&path);
1984                 kfree(journal_path);
1985         } else if (token == Opt_journal_ioprio) {
1986                 if (arg > 7) {
1987                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1988                                  " (must be 0-7)");
1989                         return -1;
1990                 }
1991                 *journal_ioprio =
1992                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1993         } else if (token == Opt_test_dummy_encryption) {
1994 #ifdef CONFIG_FS_ENCRYPTION
1995                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1996                 ext4_msg(sb, KERN_WARNING,
1997                          "Test dummy encryption mode enabled");
1998 #else
1999                 ext4_msg(sb, KERN_WARNING,
2000                          "Test dummy encryption mount option ignored");
2001 #endif
2002         } else if (m->flags & MOPT_DATAJ) {
2003                 if (is_remount) {
2004                         if (!sbi->s_journal)
2005                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2006                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2007                                 ext4_msg(sb, KERN_ERR,
2008                                          "Cannot change data mode on remount");
2009                                 return -1;
2010                         }
2011                 } else {
2012                         clear_opt(sb, DATA_FLAGS);
2013                         sbi->s_mount_opt |= m->mount_opt;
2014                 }
2015 #ifdef CONFIG_QUOTA
2016         } else if (m->flags & MOPT_QFMT) {
2017                 if (sb_any_quota_loaded(sb) &&
2018                     sbi->s_jquota_fmt != m->mount_opt) {
2019                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2020                                  "quota options when quota turned on");
2021                         return -1;
2022                 }
2023                 if (ext4_has_feature_quota(sb)) {
2024                         ext4_msg(sb, KERN_INFO,
2025                                  "Quota format mount options ignored "
2026                                  "when QUOTA feature is enabled");
2027                         return 1;
2028                 }
2029                 sbi->s_jquota_fmt = m->mount_opt;
2030 #endif
2031         } else if (token == Opt_dax) {
2032 #ifdef CONFIG_FS_DAX
2033                 ext4_msg(sb, KERN_WARNING,
2034                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2035                 sbi->s_mount_opt |= m->mount_opt;
2036 #else
2037                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2038                 return -1;
2039 #endif
2040         } else if (token == Opt_data_err_abort) {
2041                 sbi->s_mount_opt |= m->mount_opt;
2042         } else if (token == Opt_data_err_ignore) {
2043                 sbi->s_mount_opt &= ~m->mount_opt;
2044         } else {
2045                 if (!args->from)
2046                         arg = 1;
2047                 if (m->flags & MOPT_CLEAR)
2048                         arg = !arg;
2049                 else if (unlikely(!(m->flags & MOPT_SET))) {
2050                         ext4_msg(sb, KERN_WARNING,
2051                                  "buggy handling of option %s", opt);
2052                         WARN_ON(1);
2053                         return -1;
2054                 }
2055                 if (arg != 0)
2056                         sbi->s_mount_opt |= m->mount_opt;
2057                 else
2058                         sbi->s_mount_opt &= ~m->mount_opt;
2059         }
2060         return 1;
2061 }
2062
2063 static int parse_options(char *options, struct super_block *sb,
2064                          unsigned long *journal_devnum,
2065                          unsigned int *journal_ioprio,
2066                          int is_remount)
2067 {
2068         struct ext4_sb_info *sbi = EXT4_SB(sb);
2069         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2070         substring_t args[MAX_OPT_ARGS];
2071         int token;
2072
2073         if (!options)
2074                 return 1;
2075
2076         while ((p = strsep(&options, ",")) != NULL) {
2077                 if (!*p)
2078                         continue;
2079                 /*
2080                  * Initialize args struct so we know whether arg was
2081                  * found; some options take optional arguments.
2082                  */
2083                 args[0].to = args[0].from = NULL;
2084                 token = match_token(p, tokens, args);
2085                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2086                                      journal_ioprio, is_remount) < 0)
2087                         return 0;
2088         }
2089 #ifdef CONFIG_QUOTA
2090         /*
2091          * We do the test below only for project quotas. 'usrquota' and
2092          * 'grpquota' mount options are allowed even without quota feature
2093          * to support legacy quotas in quota files.
2094          */
2095         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2096                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2097                          "Cannot enable project quota enforcement.");
2098                 return 0;
2099         }
2100         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2101         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2102         if (usr_qf_name || grp_qf_name) {
2103                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2104                         clear_opt(sb, USRQUOTA);
2105
2106                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2107                         clear_opt(sb, GRPQUOTA);
2108
2109                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2110                         ext4_msg(sb, KERN_ERR, "old and new quota "
2111                                         "format mixing");
2112                         return 0;
2113                 }
2114
2115                 if (!sbi->s_jquota_fmt) {
2116                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2117                                         "not specified");
2118                         return 0;
2119                 }
2120         }
2121 #endif
2122         if (test_opt(sb, DIOREAD_NOLOCK)) {
2123                 int blocksize =
2124                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2125
2126                 if (blocksize < PAGE_SIZE) {
2127                         ext4_msg(sb, KERN_ERR, "can't mount with "
2128                                  "dioread_nolock if block size != PAGE_SIZE");
2129                         return 0;
2130                 }
2131         }
2132         return 1;
2133 }
2134
2135 static inline void ext4_show_quota_options(struct seq_file *seq,
2136                                            struct super_block *sb)
2137 {
2138 #if defined(CONFIG_QUOTA)
2139         struct ext4_sb_info *sbi = EXT4_SB(sb);
2140         char *usr_qf_name, *grp_qf_name;
2141
2142         if (sbi->s_jquota_fmt) {
2143                 char *fmtname = "";
2144
2145                 switch (sbi->s_jquota_fmt) {
2146                 case QFMT_VFS_OLD:
2147                         fmtname = "vfsold";
2148                         break;
2149                 case QFMT_VFS_V0:
2150                         fmtname = "vfsv0";
2151                         break;
2152                 case QFMT_VFS_V1:
2153                         fmtname = "vfsv1";
2154                         break;
2155                 }
2156                 seq_printf(seq, ",jqfmt=%s", fmtname);
2157         }
2158
2159         rcu_read_lock();
2160         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2161         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2162         if (usr_qf_name)
2163                 seq_show_option(seq, "usrjquota", usr_qf_name);
2164         if (grp_qf_name)
2165                 seq_show_option(seq, "grpjquota", grp_qf_name);
2166         rcu_read_unlock();
2167 #endif
2168 }
2169
2170 static const char *token2str(int token)
2171 {
2172         const struct match_token *t;
2173
2174         for (t = tokens; t->token != Opt_err; t++)
2175                 if (t->token == token && !strchr(t->pattern, '='))
2176                         break;
2177         return t->pattern;
2178 }
2179
2180 /*
2181  * Show an option if
2182  *  - it's set to a non-default value OR
2183  *  - if the per-sb default is different from the global default
2184  */
2185 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2186                               int nodefs)
2187 {
2188         struct ext4_sb_info *sbi = EXT4_SB(sb);
2189         struct ext4_super_block *es = sbi->s_es;
2190         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2191         const struct mount_opts *m;
2192         char sep = nodefs ? '\n' : ',';
2193
2194 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2195 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2196
2197         if (sbi->s_sb_block != 1)
2198                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2199
2200         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2201                 int want_set = m->flags & MOPT_SET;
2202                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2203                     (m->flags & MOPT_CLEAR_ERR))
2204                         continue;
2205                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2206                         continue; /* skip if same as the default */
2207                 if ((want_set &&
2208                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2209                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2210                         continue; /* select Opt_noFoo vs Opt_Foo */
2211                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2212         }
2213
2214         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2215             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2216                 SEQ_OPTS_PRINT("resuid=%u",
2217                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2218         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2219             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2220                 SEQ_OPTS_PRINT("resgid=%u",
2221                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2222         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2223         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2224                 SEQ_OPTS_PUTS("errors=remount-ro");
2225         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2226                 SEQ_OPTS_PUTS("errors=continue");
2227         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2228                 SEQ_OPTS_PUTS("errors=panic");
2229         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2230                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2231         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2232                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2233         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2234                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2235         if (sb->s_flags & SB_I_VERSION)
2236                 SEQ_OPTS_PUTS("i_version");
2237         if (nodefs || sbi->s_stripe)
2238                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2239         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2240                         (sbi->s_mount_opt ^ def_mount_opt)) {
2241                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2242                         SEQ_OPTS_PUTS("data=journal");
2243                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2244                         SEQ_OPTS_PUTS("data=ordered");
2245                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2246                         SEQ_OPTS_PUTS("data=writeback");
2247         }
2248         if (nodefs ||
2249             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2250                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2251                                sbi->s_inode_readahead_blks);
2252
2253         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2254                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2255                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2256         if (nodefs || sbi->s_max_dir_size_kb)
2257                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2258         if (test_opt(sb, DATA_ERR_ABORT))
2259                 SEQ_OPTS_PUTS("data_err=abort");
2260         if (DUMMY_ENCRYPTION_ENABLED(sbi))
2261                 SEQ_OPTS_PUTS("test_dummy_encryption");
2262
2263         ext4_show_quota_options(seq, sb);
2264         return 0;
2265 }
2266
2267 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2268 {
2269         return _ext4_show_options(seq, root->d_sb, 0);
2270 }
2271
2272 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2273 {
2274         struct super_block *sb = seq->private;
2275         int rc;
2276
2277         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2278         rc = _ext4_show_options(seq, sb, 1);
2279         seq_puts(seq, "\n");
2280         return rc;
2281 }
2282
2283 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2284                             int read_only)
2285 {
2286         struct ext4_sb_info *sbi = EXT4_SB(sb);
2287         int err = 0;
2288
2289         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2290                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2291                          "forcing read-only mode");
2292                 err = -EROFS;
2293         }
2294         if (read_only)
2295                 goto done;
2296         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2297                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2298                          "running e2fsck is recommended");
2299         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2300                 ext4_msg(sb, KERN_WARNING,
2301                          "warning: mounting fs with errors, "
2302                          "running e2fsck is recommended");
2303         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2304                  le16_to_cpu(es->s_mnt_count) >=
2305                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2306                 ext4_msg(sb, KERN_WARNING,
2307                          "warning: maximal mount count reached, "
2308                          "running e2fsck is recommended");
2309         else if (le32_to_cpu(es->s_checkinterval) &&
2310                  (ext4_get_tstamp(es, s_lastcheck) +
2311                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2312                 ext4_msg(sb, KERN_WARNING,
2313                          "warning: checktime reached, "
2314                          "running e2fsck is recommended");
2315         if (!sbi->s_journal)
2316                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2317         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2318                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2319         le16_add_cpu(&es->s_mnt_count, 1);
2320         ext4_update_tstamp(es, s_mtime);
2321         if (sbi->s_journal)
2322                 ext4_set_feature_journal_needs_recovery(sb);
2323
2324         err = ext4_commit_super(sb, 1);
2325 done:
2326         if (test_opt(sb, DEBUG))
2327                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2328                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2329                         sb->s_blocksize,
2330                         sbi->s_groups_count,
2331                         EXT4_BLOCKS_PER_GROUP(sb),
2332                         EXT4_INODES_PER_GROUP(sb),
2333                         sbi->s_mount_opt, sbi->s_mount_opt2);
2334
2335         cleancache_init_fs(sb);
2336         return err;
2337 }
2338
2339 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2340 {
2341         struct ext4_sb_info *sbi = EXT4_SB(sb);
2342         struct flex_groups *new_groups;
2343         int size;
2344
2345         if (!sbi->s_log_groups_per_flex)
2346                 return 0;
2347
2348         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2349         if (size <= sbi->s_flex_groups_allocated)
2350                 return 0;
2351
2352         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
2353         new_groups = kvzalloc(size, GFP_KERNEL);
2354         if (!new_groups) {
2355                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
2356                          size / (int) sizeof(struct flex_groups));
2357                 return -ENOMEM;
2358         }
2359
2360         if (sbi->s_flex_groups) {
2361                 memcpy(new_groups, sbi->s_flex_groups,
2362                        (sbi->s_flex_groups_allocated *
2363                         sizeof(struct flex_groups)));
2364                 kvfree(sbi->s_flex_groups);
2365         }
2366         sbi->s_flex_groups = new_groups;
2367         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
2368         return 0;
2369 }
2370
2371 static int ext4_fill_flex_info(struct super_block *sb)
2372 {
2373         struct ext4_sb_info *sbi = EXT4_SB(sb);
2374         struct ext4_group_desc *gdp = NULL;
2375         ext4_group_t flex_group;
2376         int i, err;
2377
2378         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2379         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2380                 sbi->s_log_groups_per_flex = 0;
2381                 return 1;
2382         }
2383
2384         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2385         if (err)
2386                 goto failed;
2387
2388         for (i = 0; i < sbi->s_groups_count; i++) {
2389                 gdp = ext4_get_group_desc(sb, i, NULL);
2390
2391                 flex_group = ext4_flex_group(sbi, i);
2392                 atomic_add(ext4_free_inodes_count(sb, gdp),
2393                            &sbi->s_flex_groups[flex_group].free_inodes);
2394                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2395                              &sbi->s_flex_groups[flex_group].free_clusters);
2396                 atomic_add(ext4_used_dirs_count(sb, gdp),
2397                            &sbi->s_flex_groups[flex_group].used_dirs);
2398         }
2399
2400         return 1;
2401 failed:
2402         return 0;
2403 }
2404
2405 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2406                                    struct ext4_group_desc *gdp)
2407 {
2408         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2409         __u16 crc = 0;
2410         __le32 le_group = cpu_to_le32(block_group);
2411         struct ext4_sb_info *sbi = EXT4_SB(sb);
2412
2413         if (ext4_has_metadata_csum(sbi->s_sb)) {
2414                 /* Use new metadata_csum algorithm */
2415                 __u32 csum32;
2416                 __u16 dummy_csum = 0;
2417
2418                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2419                                      sizeof(le_group));
2420                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2421                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2422                                      sizeof(dummy_csum));
2423                 offset += sizeof(dummy_csum);
2424                 if (offset < sbi->s_desc_size)
2425                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2426                                              sbi->s_desc_size - offset);
2427
2428                 crc = csum32 & 0xFFFF;
2429                 goto out;
2430         }
2431
2432         /* old crc16 code */
2433         if (!ext4_has_feature_gdt_csum(sb))
2434                 return 0;
2435
2436         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2437         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2438         crc = crc16(crc, (__u8 *)gdp, offset);
2439         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2440         /* for checksum of struct ext4_group_desc do the rest...*/
2441         if (ext4_has_feature_64bit(sb) &&
2442             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2443                 crc = crc16(crc, (__u8 *)gdp + offset,
2444                             le16_to_cpu(sbi->s_es->s_desc_size) -
2445                                 offset);
2446
2447 out:
2448         return cpu_to_le16(crc);
2449 }
2450
2451 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2452                                 struct ext4_group_desc *gdp)
2453 {
2454         if (ext4_has_group_desc_csum(sb) &&
2455             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2456                 return 0;
2457
2458         return 1;
2459 }
2460
2461 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2462                               struct ext4_group_desc *gdp)
2463 {
2464         if (!ext4_has_group_desc_csum(sb))
2465                 return;
2466         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2467 }
2468
2469 /* Called at mount-time, super-block is locked */
2470 static int ext4_check_descriptors(struct super_block *sb,
2471                                   ext4_fsblk_t sb_block,
2472                                   ext4_group_t *first_not_zeroed)
2473 {
2474         struct ext4_sb_info *sbi = EXT4_SB(sb);
2475         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2476         ext4_fsblk_t last_block;
2477         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2478         ext4_fsblk_t block_bitmap;
2479         ext4_fsblk_t inode_bitmap;
2480         ext4_fsblk_t inode_table;
2481         int flexbg_flag = 0;
2482         ext4_group_t i, grp = sbi->s_groups_count;
2483
2484         if (ext4_has_feature_flex_bg(sb))
2485                 flexbg_flag = 1;
2486
2487         ext4_debug("Checking group descriptors");
2488
2489         for (i = 0; i < sbi->s_groups_count; i++) {
2490                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2491
2492                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2493                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2494                 else
2495                         last_block = first_block +
2496                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2497
2498                 if ((grp == sbi->s_groups_count) &&
2499                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2500                         grp = i;
2501
2502                 block_bitmap = ext4_block_bitmap(sb, gdp);
2503                 if (block_bitmap == sb_block) {
2504                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2505                                  "Block bitmap for group %u overlaps "
2506                                  "superblock", i);
2507                         if (!sb_rdonly(sb))
2508                                 return 0;
2509                 }
2510                 if (block_bitmap >= sb_block + 1 &&
2511                     block_bitmap <= last_bg_block) {
2512                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2513                                  "Block bitmap for group %u overlaps "
2514                                  "block group descriptors", i);
2515                         if (!sb_rdonly(sb))
2516                                 return 0;
2517                 }
2518                 if (block_bitmap < first_block || block_bitmap > last_block) {
2519                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2520                                "Block bitmap for group %u not in group "
2521                                "(block %llu)!", i, block_bitmap);
2522                         return 0;
2523                 }
2524                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2525                 if (inode_bitmap == sb_block) {
2526                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2527                                  "Inode bitmap for group %u overlaps "
2528                                  "superblock", i);
2529                         if (!sb_rdonly(sb))
2530                                 return 0;
2531                 }
2532                 if (inode_bitmap >= sb_block + 1 &&
2533                     inode_bitmap <= last_bg_block) {
2534                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2535                                  "Inode bitmap for group %u overlaps "
2536                                  "block group descriptors", i);
2537                         if (!sb_rdonly(sb))
2538                                 return 0;
2539                 }
2540                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2541                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2542                                "Inode bitmap for group %u not in group "
2543                                "(block %llu)!", i, inode_bitmap);
2544                         return 0;
2545                 }
2546                 inode_table = ext4_inode_table(sb, gdp);
2547                 if (inode_table == sb_block) {
2548                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2549                                  "Inode table for group %u overlaps "
2550                                  "superblock", i);
2551                         if (!sb_rdonly(sb))
2552                                 return 0;
2553                 }
2554                 if (inode_table >= sb_block + 1 &&
2555                     inode_table <= last_bg_block) {
2556                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2557                                  "Inode table for group %u overlaps "
2558                                  "block group descriptors", i);
2559                         if (!sb_rdonly(sb))
2560                                 return 0;
2561                 }
2562                 if (inode_table < first_block ||
2563                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2564                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2565                                "Inode table for group %u not in group "
2566                                "(block %llu)!", i, inode_table);
2567                         return 0;
2568                 }
2569                 ext4_lock_group(sb, i);
2570                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2571                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2572                                  "Checksum for group %u failed (%u!=%u)",
2573                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2574                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2575                         if (!sb_rdonly(sb)) {
2576                                 ext4_unlock_group(sb, i);
2577                                 return 0;
2578                         }
2579                 }
2580                 ext4_unlock_group(sb, i);
2581                 if (!flexbg_flag)
2582                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2583         }
2584         if (NULL != first_not_zeroed)
2585                 *first_not_zeroed = grp;
2586         return 1;
2587 }
2588
2589 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2590  * the superblock) which were deleted from all directories, but held open by
2591  * a process at the time of a crash.  We walk the list and try to delete these
2592  * inodes at recovery time (only with a read-write filesystem).
2593  *
2594  * In order to keep the orphan inode chain consistent during traversal (in
2595  * case of crash during recovery), we link each inode into the superblock
2596  * orphan list_head and handle it the same way as an inode deletion during
2597  * normal operation (which journals the operations for us).
2598  *
2599  * We only do an iget() and an iput() on each inode, which is very safe if we
2600  * accidentally point at an in-use or already deleted inode.  The worst that
2601  * can happen in this case is that we get a "bit already cleared" message from
2602  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2603  * e2fsck was run on this filesystem, and it must have already done the orphan
2604  * inode cleanup for us, so we can safely abort without any further action.
2605  */
2606 static void ext4_orphan_cleanup(struct super_block *sb,
2607                                 struct ext4_super_block *es)
2608 {
2609         unsigned int s_flags = sb->s_flags;
2610         int ret, nr_orphans = 0, nr_truncates = 0;
2611 #ifdef CONFIG_QUOTA
2612         int quota_update = 0;
2613         int i;
2614 #endif
2615         if (!es->s_last_orphan) {
2616                 jbd_debug(4, "no orphan inodes to clean up\n");
2617                 return;
2618         }
2619
2620         if (bdev_read_only(sb->s_bdev)) {
2621                 ext4_msg(sb, KERN_ERR, "write access "
2622                         "unavailable, skipping orphan cleanup");
2623                 return;
2624         }
2625
2626         /* Check if feature set would not allow a r/w mount */
2627         if (!ext4_feature_set_ok(sb, 0)) {
2628                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2629                          "unknown ROCOMPAT features");
2630                 return;
2631         }
2632
2633         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2634                 /* don't clear list on RO mount w/ errors */
2635                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2636                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2637                                   "clearing orphan list.\n");
2638                         es->s_last_orphan = 0;
2639                 }
2640                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2641                 return;
2642         }
2643
2644         if (s_flags & SB_RDONLY) {
2645                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2646                 sb->s_flags &= ~SB_RDONLY;
2647         }
2648 #ifdef CONFIG_QUOTA
2649         /* Needed for iput() to work correctly and not trash data */
2650         sb->s_flags |= SB_ACTIVE;
2651
2652         /*
2653          * Turn on quotas which were not enabled for read-only mounts if
2654          * filesystem has quota feature, so that they are updated correctly.
2655          */
2656         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2657                 int ret = ext4_enable_quotas(sb);
2658
2659                 if (!ret)
2660                         quota_update = 1;
2661                 else
2662                         ext4_msg(sb, KERN_ERR,
2663                                 "Cannot turn on quotas: error %d", ret);
2664         }
2665
2666         /* Turn on journaled quotas used for old sytle */
2667         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2668                 if (EXT4_SB(sb)->s_qf_names[i]) {
2669                         int ret = ext4_quota_on_mount(sb, i);
2670
2671                         if (!ret)
2672                                 quota_update = 1;
2673                         else
2674                                 ext4_msg(sb, KERN_ERR,
2675                                         "Cannot turn on journaled "
2676                                         "quota: type %d: error %d", i, ret);
2677                 }
2678         }
2679 #endif
2680
2681         while (es->s_last_orphan) {
2682                 struct inode *inode;
2683
2684                 /*
2685                  * We may have encountered an error during cleanup; if
2686                  * so, skip the rest.
2687                  */
2688                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2689                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2690                         es->s_last_orphan = 0;
2691                         break;
2692                 }
2693
2694                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2695                 if (IS_ERR(inode)) {
2696                         es->s_last_orphan = 0;
2697                         break;
2698                 }
2699
2700                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2701                 dquot_initialize(inode);
2702                 if (inode->i_nlink) {
2703                         if (test_opt(sb, DEBUG))
2704                                 ext4_msg(sb, KERN_DEBUG,
2705                                         "%s: truncating inode %lu to %lld bytes",
2706                                         __func__, inode->i_ino, inode->i_size);
2707                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2708                                   inode->i_ino, inode->i_size);
2709                         inode_lock(inode);
2710                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2711                         ret = ext4_truncate(inode);
2712                         if (ret)
2713                                 ext4_std_error(inode->i_sb, ret);
2714                         inode_unlock(inode);
2715                         nr_truncates++;
2716                 } else {
2717                         if (test_opt(sb, DEBUG))
2718                                 ext4_msg(sb, KERN_DEBUG,
2719                                         "%s: deleting unreferenced inode %lu",
2720                                         __func__, inode->i_ino);
2721                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2722                                   inode->i_ino);
2723                         nr_orphans++;
2724                 }
2725                 iput(inode);  /* The delete magic happens here! */
2726         }
2727
2728 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2729
2730         if (nr_orphans)
2731                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2732                        PLURAL(nr_orphans));
2733         if (nr_truncates)
2734                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2735                        PLURAL(nr_truncates));
2736 #ifdef CONFIG_QUOTA
2737         /* Turn off quotas if they were enabled for orphan cleanup */
2738         if (quota_update) {
2739                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2740                         if (sb_dqopt(sb)->files[i])
2741                                 dquot_quota_off(sb, i);
2742                 }
2743         }
2744 #endif
2745         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2746 }
2747
2748 /*
2749  * Maximal extent format file size.
2750  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2751  * extent format containers, within a sector_t, and within i_blocks
2752  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2753  * so that won't be a limiting factor.
2754  *
2755  * However there is other limiting factor. We do store extents in the form
2756  * of starting block and length, hence the resulting length of the extent
2757  * covering maximum file size must fit into on-disk format containers as
2758  * well. Given that length is always by 1 unit bigger than max unit (because
2759  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2760  *
2761  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2762  */
2763 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2764 {
2765         loff_t res;
2766         loff_t upper_limit = MAX_LFS_FILESIZE;
2767
2768         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
2769
2770         if (!has_huge_files) {
2771                 upper_limit = (1LL << 32) - 1;
2772
2773                 /* total blocks in file system block size */
2774                 upper_limit >>= (blkbits - 9);
2775                 upper_limit <<= blkbits;
2776         }
2777
2778         /*
2779          * 32-bit extent-start container, ee_block. We lower the maxbytes
2780          * by one fs block, so ee_len can cover the extent of maximum file
2781          * size
2782          */
2783         res = (1LL << 32) - 1;
2784         res <<= blkbits;
2785
2786         /* Sanity check against vm- & vfs- imposed limits */
2787         if (res > upper_limit)
2788                 res = upper_limit;
2789
2790         return res;
2791 }
2792
2793 /*
2794  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2795  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2796  * We need to be 1 filesystem block less than the 2^48 sector limit.
2797  */
2798 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2799 {
2800         loff_t res = EXT4_NDIR_BLOCKS;
2801         int meta_blocks;
2802         loff_t upper_limit;
2803         /* This is calculated to be the largest file size for a dense, block
2804          * mapped file such that the file's total number of 512-byte sectors,
2805          * including data and all indirect blocks, does not exceed (2^48 - 1).
2806          *
2807          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2808          * number of 512-byte sectors of the file.
2809          */
2810
2811         if (!has_huge_files) {
2812                 /*
2813                  * !has_huge_files or implies that the inode i_block field
2814                  * represents total file blocks in 2^32 512-byte sectors ==
2815                  * size of vfs inode i_blocks * 8
2816                  */
2817                 upper_limit = (1LL << 32) - 1;
2818
2819                 /* total blocks in file system block size */
2820                 upper_limit >>= (bits - 9);
2821
2822         } else {
2823                 /*
2824                  * We use 48 bit ext4_inode i_blocks
2825                  * With EXT4_HUGE_FILE_FL set the i_blocks
2826                  * represent total number of blocks in
2827                  * file system block size
2828                  */
2829                 upper_limit = (1LL << 48) - 1;
2830
2831         }
2832
2833         /* indirect blocks */
2834         meta_blocks = 1;
2835         /* double indirect blocks */
2836         meta_blocks += 1 + (1LL << (bits-2));
2837         /* tripple indirect blocks */
2838         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2839
2840         upper_limit -= meta_blocks;
2841         upper_limit <<= bits;
2842
2843         res += 1LL << (bits-2);
2844         res += 1LL << (2*(bits-2));
2845         res += 1LL << (3*(bits-2));
2846         res <<= bits;
2847         if (res > upper_limit)
2848                 res = upper_limit;
2849
2850         if (res > MAX_LFS_FILESIZE)
2851                 res = MAX_LFS_FILESIZE;
2852
2853         return res;
2854 }
2855
2856 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2857                                    ext4_fsblk_t logical_sb_block, int nr)
2858 {
2859         struct ext4_sb_info *sbi = EXT4_SB(sb);
2860         ext4_group_t bg, first_meta_bg;
2861         int has_super = 0;
2862
2863         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2864
2865         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2866                 return logical_sb_block + nr + 1;
2867         bg = sbi->s_desc_per_block * nr;
2868         if (ext4_bg_has_super(sb, bg))
2869                 has_super = 1;
2870
2871         /*
2872          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2873          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2874          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2875          * compensate.
2876          */
2877         if (sb->s_blocksize == 1024 && nr == 0 &&
2878             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
2879                 has_super++;
2880
2881         return (has_super + ext4_group_first_block_no(sb, bg));
2882 }
2883
2884 /**
2885  * ext4_get_stripe_size: Get the stripe size.
2886  * @sbi: In memory super block info
2887  *
2888  * If we have specified it via mount option, then
2889  * use the mount option value. If the value specified at mount time is
2890  * greater than the blocks per group use the super block value.
2891  * If the super block value is greater than blocks per group return 0.
2892  * Allocator needs it be less than blocks per group.
2893  *
2894  */
2895 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2896 {
2897         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2898         unsigned long stripe_width =
2899                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2900         int ret;
2901
2902         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2903                 ret = sbi->s_stripe;
2904         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2905                 ret = stripe_width;
2906         else if (stride && stride <= sbi->s_blocks_per_group)
2907                 ret = stride;
2908         else
2909                 ret = 0;
2910
2911         /*
2912          * If the stripe width is 1, this makes no sense and
2913          * we set it to 0 to turn off stripe handling code.
2914          */
2915         if (ret <= 1)
2916                 ret = 0;
2917
2918         return ret;
2919 }
2920
2921 /*
2922  * Check whether this filesystem can be mounted based on
2923  * the features present and the RDONLY/RDWR mount requested.
2924  * Returns 1 if this filesystem can be mounted as requested,
2925  * 0 if it cannot be.
2926  */
2927 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2928 {
2929         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2930                 ext4_msg(sb, KERN_ERR,
2931                         "Couldn't mount because of "
2932                         "unsupported optional features (%x)",
2933                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2934                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2935                 return 0;
2936         }
2937
2938 #ifndef CONFIG_UNICODE
2939         if (ext4_has_feature_casefold(sb)) {
2940                 ext4_msg(sb, KERN_ERR,
2941                          "Filesystem with casefold feature cannot be "
2942                          "mounted without CONFIG_UNICODE");
2943                 return 0;
2944         }
2945 #endif
2946
2947         if (readonly)
2948                 return 1;
2949
2950         if (ext4_has_feature_readonly(sb)) {
2951                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2952                 sb->s_flags |= SB_RDONLY;
2953                 return 1;
2954         }
2955
2956         /* Check that feature set is OK for a read-write mount */
2957         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2958                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2959                          "unsupported optional features (%x)",
2960                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2961                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2962                 return 0;
2963         }
2964         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2965                 ext4_msg(sb, KERN_ERR,
2966                          "Can't support bigalloc feature without "
2967                          "extents feature\n");
2968                 return 0;
2969         }
2970
2971 #ifndef CONFIG_QUOTA
2972         if (ext4_has_feature_quota(sb) && !readonly) {
2973                 ext4_msg(sb, KERN_ERR,
2974                          "Filesystem with quota feature cannot be mounted RDWR "
2975                          "without CONFIG_QUOTA");
2976                 return 0;
2977         }
2978         if (ext4_has_feature_project(sb) && !readonly) {
2979                 ext4_msg(sb, KERN_ERR,
2980                          "Filesystem with project quota feature cannot be mounted RDWR "
2981                          "without CONFIG_QUOTA");
2982                 return 0;
2983         }
2984 #endif  /* CONFIG_QUOTA */
2985         return 1;
2986 }
2987
2988 /*
2989  * This function is called once a day if we have errors logged
2990  * on the file system
2991  */
2992 static void print_daily_error_info(struct timer_list *t)
2993 {
2994         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
2995         struct super_block *sb = sbi->s_sb;
2996         struct ext4_super_block *es = sbi->s_es;
2997
2998         if (es->s_error_count)
2999                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3000                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3001                          le32_to_cpu(es->s_error_count));
3002         if (es->s_first_error_time) {
3003                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3004                        sb->s_id,
3005                        ext4_get_tstamp(es, s_first_error_time),
3006                        (int) sizeof(es->s_first_error_func),
3007                        es->s_first_error_func,
3008                        le32_to_cpu(es->s_first_error_line));
3009                 if (es->s_first_error_ino)
3010                         printk(KERN_CONT ": inode %u",
3011                                le32_to_cpu(es->s_first_error_ino));
3012                 if (es->s_first_error_block)
3013                         printk(KERN_CONT ": block %llu", (unsigned long long)
3014                                le64_to_cpu(es->s_first_error_block));
3015                 printk(KERN_CONT "\n");
3016         }
3017         if (es->s_last_error_time) {
3018                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3019                        sb->s_id,
3020                        ext4_get_tstamp(es, s_last_error_time),
3021                        (int) sizeof(es->s_last_error_func),
3022                        es->s_last_error_func,
3023                        le32_to_cpu(es->s_last_error_line));
3024                 if (es->s_last_error_ino)
3025                         printk(KERN_CONT ": inode %u",
3026                                le32_to_cpu(es->s_last_error_ino));
3027                 if (es->s_last_error_block)
3028                         printk(KERN_CONT ": block %llu", (unsigned long long)
3029                                le64_to_cpu(es->s_last_error_block));
3030                 printk(KERN_CONT "\n");
3031         }
3032         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3033 }
3034
3035 /* Find next suitable group and run ext4_init_inode_table */
3036 static int ext4_run_li_request(struct ext4_li_request *elr)
3037 {
3038         struct ext4_group_desc *gdp = NULL;
3039         ext4_group_t group, ngroups;
3040         struct super_block *sb;
3041         unsigned long timeout = 0;
3042         int ret = 0;
3043
3044         sb = elr->lr_super;
3045         ngroups = EXT4_SB(sb)->s_groups_count;
3046
3047         for (group = elr->lr_next_group; group < ngroups; group++) {
3048                 gdp = ext4_get_group_desc(sb, group, NULL);
3049                 if (!gdp) {
3050                         ret = 1;
3051                         break;
3052                 }
3053
3054                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3055                         break;
3056         }
3057
3058         if (group >= ngroups)
3059                 ret = 1;
3060
3061         if (!ret) {
3062                 timeout = jiffies;
3063                 ret = ext4_init_inode_table(sb, group,
3064                                             elr->lr_timeout ? 0 : 1);
3065                 if (elr->lr_timeout == 0) {
3066                         timeout = (jiffies - timeout) *
3067                                   elr->lr_sbi->s_li_wait_mult;
3068                         elr->lr_timeout = timeout;
3069                 }
3070                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3071                 elr->lr_next_group = group + 1;
3072         }
3073         return ret;
3074 }
3075
3076 /*
3077  * Remove lr_request from the list_request and free the
3078  * request structure. Should be called with li_list_mtx held
3079  */
3080 static void ext4_remove_li_request(struct ext4_li_request *elr)
3081 {
3082         struct ext4_sb_info *sbi;
3083
3084         if (!elr)
3085                 return;
3086
3087         sbi = elr->lr_sbi;
3088
3089         list_del(&elr->lr_request);
3090         sbi->s_li_request = NULL;
3091         kfree(elr);
3092 }
3093
3094 static void ext4_unregister_li_request(struct super_block *sb)
3095 {
3096         mutex_lock(&ext4_li_mtx);
3097         if (!ext4_li_info) {
3098                 mutex_unlock(&ext4_li_mtx);
3099                 return;
3100         }
3101
3102         mutex_lock(&ext4_li_info->li_list_mtx);
3103         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3104         mutex_unlock(&ext4_li_info->li_list_mtx);
3105         mutex_unlock(&ext4_li_mtx);
3106 }
3107
3108 static struct task_struct *ext4_lazyinit_task;
3109
3110 /*
3111  * This is the function where ext4lazyinit thread lives. It walks
3112  * through the request list searching for next scheduled filesystem.
3113  * When such a fs is found, run the lazy initialization request
3114  * (ext4_rn_li_request) and keep track of the time spend in this
3115  * function. Based on that time we compute next schedule time of
3116  * the request. When walking through the list is complete, compute
3117  * next waking time and put itself into sleep.
3118  */
3119 static int ext4_lazyinit_thread(void *arg)
3120 {
3121         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3122         struct list_head *pos, *n;
3123         struct ext4_li_request *elr;
3124         unsigned long next_wakeup, cur;
3125
3126         BUG_ON(NULL == eli);
3127
3128 cont_thread:
3129         while (true) {
3130                 next_wakeup = MAX_JIFFY_OFFSET;
3131
3132                 mutex_lock(&eli->li_list_mtx);
3133                 if (list_empty(&eli->li_request_list)) {
3134                         mutex_unlock(&eli->li_list_mtx);
3135                         goto exit_thread;
3136                 }
3137                 list_for_each_safe(pos, n, &eli->li_request_list) {
3138                         int err = 0;
3139                         int progress = 0;
3140                         elr = list_entry(pos, struct ext4_li_request,
3141                                          lr_request);
3142
3143                         if (time_before(jiffies, elr->lr_next_sched)) {
3144                                 if (time_before(elr->lr_next_sched, next_wakeup))
3145                                         next_wakeup = elr->lr_next_sched;
3146                                 continue;
3147                         }
3148                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3149                                 if (sb_start_write_trylock(elr->lr_super)) {
3150                                         progress = 1;
3151                                         /*
3152                                          * We hold sb->s_umount, sb can not
3153                                          * be removed from the list, it is
3154                                          * now safe to drop li_list_mtx
3155                                          */
3156                                         mutex_unlock(&eli->li_list_mtx);
3157                                         err = ext4_run_li_request(elr);
3158                                         sb_end_write(elr->lr_super);
3159                                         mutex_lock(&eli->li_list_mtx);
3160                                         n = pos->next;
3161                                 }
3162                                 up_read((&elr->lr_super->s_umount));
3163                         }
3164                         /* error, remove the lazy_init job */
3165                         if (err) {
3166                                 ext4_remove_li_request(elr);
3167                                 continue;
3168                         }
3169                         if (!progress) {
3170                                 elr->lr_next_sched = jiffies +
3171                                         (prandom_u32()
3172                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3173                         }
3174                         if (time_before(elr->lr_next_sched, next_wakeup))
3175                                 next_wakeup = elr->lr_next_sched;
3176                 }
3177                 mutex_unlock(&eli->li_list_mtx);
3178
3179                 try_to_freeze();
3180
3181                 cur = jiffies;
3182                 if ((time_after_eq(cur, next_wakeup)) ||
3183                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3184                         cond_resched();
3185                         continue;
3186                 }
3187
3188                 schedule_timeout_interruptible(next_wakeup - cur);
3189
3190                 if (kthread_should_stop()) {
3191                         ext4_clear_request_list();
3192                         goto exit_thread;
3193                 }
3194         }
3195
3196 exit_thread:
3197         /*
3198          * It looks like the request list is empty, but we need
3199          * to check it under the li_list_mtx lock, to prevent any
3200          * additions into it, and of course we should lock ext4_li_mtx
3201          * to atomically free the list and ext4_li_info, because at
3202          * this point another ext4 filesystem could be registering
3203          * new one.
3204          */
3205         mutex_lock(&ext4_li_mtx);
3206         mutex_lock(&eli->li_list_mtx);
3207         if (!list_empty(&eli->li_request_list)) {
3208                 mutex_unlock(&eli->li_list_mtx);
3209                 mutex_unlock(&ext4_li_mtx);
3210                 goto cont_thread;
3211         }
3212         mutex_unlock(&eli->li_list_mtx);
3213         kfree(ext4_li_info);
3214         ext4_li_info = NULL;
3215         mutex_unlock(&ext4_li_mtx);
3216
3217         return 0;
3218 }
3219
3220 static void ext4_clear_request_list(void)
3221 {
3222         struct list_head *pos, *n;
3223         struct ext4_li_request *elr;
3224
3225         mutex_lock(&ext4_li_info->li_list_mtx);
3226         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3227                 elr = list_entry(pos, struct ext4_li_request,
3228                                  lr_request);
3229                 ext4_remove_li_request(elr);
3230         }
3231         mutex_unlock(&ext4_li_info->li_list_mtx);
3232 }
3233
3234 static int ext4_run_lazyinit_thread(void)
3235 {
3236         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3237                                          ext4_li_info, "ext4lazyinit");
3238         if (IS_ERR(ext4_lazyinit_task)) {
3239                 int err = PTR_ERR(ext4_lazyinit_task);
3240                 ext4_clear_request_list();
3241                 kfree(ext4_li_info);
3242                 ext4_li_info = NULL;
3243                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3244                                  "initialization thread\n",
3245                                  err);
3246                 return err;
3247         }
3248         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3249         return 0;
3250 }
3251
3252 /*
3253  * Check whether it make sense to run itable init. thread or not.
3254  * If there is at least one uninitialized inode table, return
3255  * corresponding group number, else the loop goes through all
3256  * groups and return total number of groups.
3257  */
3258 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3259 {
3260         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3261         struct ext4_group_desc *gdp = NULL;
3262
3263         if (!ext4_has_group_desc_csum(sb))
3264                 return ngroups;
3265
3266         for (group = 0; group < ngroups; group++) {
3267                 gdp = ext4_get_group_desc(sb, group, NULL);
3268                 if (!gdp)
3269                         continue;
3270
3271                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3272                         break;
3273         }
3274
3275         return group;
3276 }
3277
3278 static int ext4_li_info_new(void)
3279 {
3280         struct ext4_lazy_init *eli = NULL;
3281
3282         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3283         if (!eli)
3284                 return -ENOMEM;
3285
3286         INIT_LIST_HEAD(&eli->li_request_list);
3287         mutex_init(&eli->li_list_mtx);
3288
3289         eli->li_state |= EXT4_LAZYINIT_QUIT;
3290
3291         ext4_li_info = eli;
3292
3293         return 0;
3294 }
3295
3296 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3297                                             ext4_group_t start)
3298 {
3299         struct ext4_sb_info *sbi = EXT4_SB(sb);
3300         struct ext4_li_request *elr;
3301
3302         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3303         if (!elr)
3304                 return NULL;
3305
3306         elr->lr_super = sb;
3307         elr->lr_sbi = sbi;
3308         elr->lr_next_group = start;
3309
3310         /*
3311          * Randomize first schedule time of the request to
3312          * spread the inode table initialization requests
3313          * better.
3314          */
3315         elr->lr_next_sched = jiffies + (prandom_u32() %
3316                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3317         return elr;
3318 }
3319
3320 int ext4_register_li_request(struct super_block *sb,
3321                              ext4_group_t first_not_zeroed)
3322 {
3323         struct ext4_sb_info *sbi = EXT4_SB(sb);
3324         struct ext4_li_request *elr = NULL;
3325         ext4_group_t ngroups = sbi->s_groups_count;
3326         int ret = 0;
3327
3328         mutex_lock(&ext4_li_mtx);
3329         if (sbi->s_li_request != NULL) {
3330                 /*
3331                  * Reset timeout so it can be computed again, because
3332                  * s_li_wait_mult might have changed.
3333                  */
3334                 sbi->s_li_request->lr_timeout = 0;
3335                 goto out;
3336         }
3337
3338         if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3339             !test_opt(sb, INIT_INODE_TABLE))
3340                 goto out;
3341
3342         elr = ext4_li_request_new(sb, first_not_zeroed);
3343         if (!elr) {
3344                 ret = -ENOMEM;
3345                 goto out;
3346         }
3347
3348         if (NULL == ext4_li_info) {
3349                 ret = ext4_li_info_new();
3350                 if (ret)
3351                         goto out;
3352         }
3353
3354         mutex_lock(&ext4_li_info->li_list_mtx);
3355         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3356         mutex_unlock(&ext4_li_info->li_list_mtx);
3357
3358         sbi->s_li_request = elr;
3359         /*
3360          * set elr to NULL here since it has been inserted to
3361          * the request_list and the removal and free of it is
3362          * handled by ext4_clear_request_list from now on.
3363          */
3364         elr = NULL;
3365
3366         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3367                 ret = ext4_run_lazyinit_thread();
3368                 if (ret)
3369                         goto out;
3370         }
3371 out:
3372         mutex_unlock(&ext4_li_mtx);
3373         if (ret)
3374                 kfree(elr);
3375         return ret;
3376 }
3377
3378 /*
3379  * We do not need to lock anything since this is called on
3380  * module unload.
3381  */
3382 static void ext4_destroy_lazyinit_thread(void)
3383 {
3384         /*
3385          * If thread exited earlier
3386          * there's nothing to be done.
3387          */
3388         if (!ext4_li_info || !ext4_lazyinit_task)
3389                 return;
3390
3391         kthread_stop(ext4_lazyinit_task);
3392 }
3393
3394 static int set_journal_csum_feature_set(struct super_block *sb)
3395 {
3396         int ret = 1;
3397         int compat, incompat;
3398         struct ext4_sb_info *sbi = EXT4_SB(sb);
3399
3400         if (ext4_has_metadata_csum(sb)) {
3401                 /* journal checksum v3 */
3402                 compat = 0;
3403                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3404         } else {
3405                 /* journal checksum v1 */
3406                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3407                 incompat = 0;
3408         }
3409
3410         jbd2_journal_clear_features(sbi->s_journal,
3411                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3412                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3413                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3414         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3415                 ret = jbd2_journal_set_features(sbi->s_journal,
3416                                 compat, 0,
3417                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3418                                 incompat);
3419         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3420                 ret = jbd2_journal_set_features(sbi->s_journal,
3421                                 compat, 0,
3422                                 incompat);
3423                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3424                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3425         } else {
3426                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3427                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3428         }
3429
3430         return ret;
3431 }
3432
3433 /*
3434  * Note: calculating the overhead so we can be compatible with
3435  * historical BSD practice is quite difficult in the face of
3436  * clusters/bigalloc.  This is because multiple metadata blocks from
3437  * different block group can end up in the same allocation cluster.
3438  * Calculating the exact overhead in the face of clustered allocation
3439  * requires either O(all block bitmaps) in memory or O(number of block
3440  * groups**2) in time.  We will still calculate the superblock for
3441  * older file systems --- and if we come across with a bigalloc file
3442  * system with zero in s_overhead_clusters the estimate will be close to
3443  * correct especially for very large cluster sizes --- but for newer
3444  * file systems, it's better to calculate this figure once at mkfs
3445  * time, and store it in the superblock.  If the superblock value is
3446  * present (even for non-bigalloc file systems), we will use it.
3447  */
3448 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3449                           char *buf)
3450 {
3451         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3452         struct ext4_group_desc  *gdp;
3453         ext4_fsblk_t            first_block, last_block, b;
3454         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3455         int                     s, j, count = 0;
3456
3457         if (!ext4_has_feature_bigalloc(sb))
3458                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3459                         sbi->s_itb_per_group + 2);
3460
3461         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3462                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3463         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3464         for (i = 0; i < ngroups; i++) {
3465                 gdp = ext4_get_group_desc(sb, i, NULL);
3466                 b = ext4_block_bitmap(sb, gdp);
3467                 if (b >= first_block && b <= last_block) {
3468                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3469                         count++;
3470                 }
3471                 b = ext4_inode_bitmap(sb, gdp);
3472                 if (b >= first_block && b <= last_block) {
3473                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3474                         count++;
3475                 }
3476                 b = ext4_inode_table(sb, gdp);
3477                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3478                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3479                                 int c = EXT4_B2C(sbi, b - first_block);
3480                                 ext4_set_bit(c, buf);
3481                                 count++;
3482                         }
3483                 if (i != grp)
3484                         continue;
3485                 s = 0;
3486                 if (ext4_bg_has_super(sb, grp)) {
3487                         ext4_set_bit(s++, buf);
3488                         count++;
3489                 }
3490                 j = ext4_bg_num_gdb(sb, grp);
3491                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3492                         ext4_error(sb, "Invalid number of block group "
3493                                    "descriptor blocks: %d", j);
3494                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3495                 }
3496                 count += j;
3497                 for (; j > 0; j--)
3498                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3499         }
3500         if (!count)
3501                 return 0;
3502         return EXT4_CLUSTERS_PER_GROUP(sb) -
3503                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3504 }
3505
3506 /*
3507  * Compute the overhead and stash it in sbi->s_overhead
3508  */
3509 int ext4_calculate_overhead(struct super_block *sb)
3510 {
3511         struct ext4_sb_info *sbi = EXT4_SB(sb);
3512         struct ext4_super_block *es = sbi->s_es;
3513         struct inode *j_inode;
3514         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3515         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3516         ext4_fsblk_t overhead = 0;
3517         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3518
3519         if (!buf)
3520                 return -ENOMEM;
3521
3522         /*
3523          * Compute the overhead (FS structures).  This is constant
3524          * for a given filesystem unless the number of block groups
3525          * changes so we cache the previous value until it does.
3526          */
3527
3528         /*
3529          * All of the blocks before first_data_block are overhead
3530          */
3531         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3532
3533         /*
3534          * Add the overhead found in each block group
3535          */
3536         for (i = 0; i < ngroups; i++) {
3537                 int blks;
3538
3539                 blks = count_overhead(sb, i, buf);
3540                 overhead += blks;
3541                 if (blks)
3542                         memset(buf, 0, PAGE_SIZE);
3543                 cond_resched();
3544         }
3545
3546         /*
3547          * Add the internal journal blocks whether the journal has been
3548          * loaded or not
3549          */
3550         if (sbi->s_journal && !sbi->journal_bdev)
3551                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3552         else if (ext4_has_feature_journal(sb) && !sbi->s_journal) {
3553                 j_inode = ext4_get_journal_inode(sb, j_inum);
3554                 if (j_inode) {
3555                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3556                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3557                         iput(j_inode);
3558                 } else {
3559                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3560                 }
3561         }
3562         sbi->s_overhead = overhead;
3563         smp_wmb();
3564         free_page((unsigned long) buf);
3565         return 0;
3566 }
3567
3568 static void ext4_clamp_want_extra_isize(struct super_block *sb)
3569 {
3570         struct ext4_sb_info *sbi = EXT4_SB(sb);
3571         struct ext4_super_block *es = sbi->s_es;
3572
3573         /* determine the minimum size of new large inodes, if present */
3574         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE &&
3575             sbi->s_want_extra_isize == 0) {
3576                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3577                                                      EXT4_GOOD_OLD_INODE_SIZE;
3578                 if (ext4_has_feature_extra_isize(sb)) {
3579                         if (sbi->s_want_extra_isize <
3580                             le16_to_cpu(es->s_want_extra_isize))
3581                                 sbi->s_want_extra_isize =
3582                                         le16_to_cpu(es->s_want_extra_isize);
3583                         if (sbi->s_want_extra_isize <
3584                             le16_to_cpu(es->s_min_extra_isize))
3585                                 sbi->s_want_extra_isize =
3586                                         le16_to_cpu(es->s_min_extra_isize);
3587                 }
3588         }
3589         /* Check if enough inode space is available */
3590         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3591                                                         sbi->s_inode_size) {
3592                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3593                                                        EXT4_GOOD_OLD_INODE_SIZE;
3594                 ext4_msg(sb, KERN_INFO,
3595                          "required extra inode space not available");
3596         }
3597 }
3598
3599 static void ext4_set_resv_clusters(struct super_block *sb)
3600 {
3601         ext4_fsblk_t resv_clusters;
3602         struct ext4_sb_info *sbi = EXT4_SB(sb);
3603
3604         /*
3605          * There's no need to reserve anything when we aren't using extents.
3606          * The space estimates are exact, there are no unwritten extents,
3607          * hole punching doesn't need new metadata... This is needed especially
3608          * to keep ext2/3 backward compatibility.
3609          */
3610         if (!ext4_has_feature_extents(sb))
3611                 return;
3612         /*
3613          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3614          * This should cover the situations where we can not afford to run
3615          * out of space like for example punch hole, or converting
3616          * unwritten extents in delalloc path. In most cases such
3617          * allocation would require 1, or 2 blocks, higher numbers are
3618          * very rare.
3619          */
3620         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3621                          sbi->s_cluster_bits);
3622
3623         do_div(resv_clusters, 50);
3624         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3625
3626         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3627 }
3628
3629 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3630 {
3631         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3632         char *orig_data = kstrdup(data, GFP_KERNEL);
3633         struct buffer_head *bh;
3634         struct ext4_super_block *es = NULL;
3635         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3636         ext4_fsblk_t block;
3637         ext4_fsblk_t sb_block = get_sb_block(&data);
3638         ext4_fsblk_t logical_sb_block;
3639         unsigned long offset = 0;
3640         unsigned long journal_devnum = 0;
3641         unsigned long def_mount_opts;
3642         struct inode *root;
3643         const char *descr;
3644         int ret = -ENOMEM;
3645         int blocksize, clustersize;
3646         unsigned int db_count;
3647         unsigned int i;
3648         int needs_recovery, has_huge_files, has_bigalloc;
3649         __u64 blocks_count;
3650         int err = 0;
3651         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3652         ext4_group_t first_not_zeroed;
3653
3654         if ((data && !orig_data) || !sbi)
3655                 goto out_free_base;
3656
3657         sbi->s_daxdev = dax_dev;
3658         sbi->s_blockgroup_lock =
3659                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3660         if (!sbi->s_blockgroup_lock)
3661                 goto out_free_base;
3662
3663         sb->s_fs_info = sbi;
3664         sbi->s_sb = sb;
3665         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3666         sbi->s_sb_block = sb_block;
3667         if (sb->s_bdev->bd_part)
3668                 sbi->s_sectors_written_start =
3669                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
3670
3671         /* Cleanup superblock name */
3672         strreplace(sb->s_id, '/', '!');
3673
3674         /* -EINVAL is default */
3675         ret = -EINVAL;
3676         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3677         if (!blocksize) {
3678                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3679                 goto out_fail;
3680         }
3681
3682         /*
3683          * The ext4 superblock will not be buffer aligned for other than 1kB
3684          * block sizes.  We need to calculate the offset from buffer start.
3685          */
3686         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3687                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3688                 offset = do_div(logical_sb_block, blocksize);
3689         } else {
3690                 logical_sb_block = sb_block;
3691         }
3692
3693         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3694                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3695                 goto out_fail;
3696         }
3697         /*
3698          * Note: s_es must be initialized as soon as possible because
3699          *       some ext4 macro-instructions depend on its value
3700          */
3701         es = (struct ext4_super_block *) (bh->b_data + offset);
3702         sbi->s_es = es;
3703         sb->s_magic = le16_to_cpu(es->s_magic);
3704         if (sb->s_magic != EXT4_SUPER_MAGIC)
3705                 goto cantfind_ext4;
3706         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3707
3708         /* Warn if metadata_csum and gdt_csum are both set. */
3709         if (ext4_has_feature_metadata_csum(sb) &&
3710             ext4_has_feature_gdt_csum(sb))
3711                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3712                              "redundant flags; please run fsck.");
3713
3714         /* Check for a known checksum algorithm */
3715         if (!ext4_verify_csum_type(sb, es)) {
3716                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3717                          "unknown checksum algorithm.");
3718                 silent = 1;
3719                 goto cantfind_ext4;
3720         }
3721
3722         /* Load the checksum driver */
3723         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3724         if (IS_ERR(sbi->s_chksum_driver)) {
3725                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3726                 ret = PTR_ERR(sbi->s_chksum_driver);
3727                 sbi->s_chksum_driver = NULL;
3728                 goto failed_mount;
3729         }
3730
3731         /* Check superblock checksum */
3732         if (!ext4_superblock_csum_verify(sb, es)) {
3733                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3734                          "invalid superblock checksum.  Run e2fsck?");
3735                 silent = 1;
3736                 ret = -EFSBADCRC;
3737                 goto cantfind_ext4;
3738         }
3739
3740         /* Precompute checksum seed for all metadata */
3741         if (ext4_has_feature_csum_seed(sb))
3742                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3743         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3744                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3745                                                sizeof(es->s_uuid));
3746
3747         /* Set defaults before we parse the mount options */
3748         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3749         set_opt(sb, INIT_INODE_TABLE);
3750         if (def_mount_opts & EXT4_DEFM_DEBUG)
3751                 set_opt(sb, DEBUG);
3752         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3753                 set_opt(sb, GRPID);
3754         if (def_mount_opts & EXT4_DEFM_UID16)
3755                 set_opt(sb, NO_UID32);
3756         /* xattr user namespace & acls are now defaulted on */
3757         set_opt(sb, XATTR_USER);
3758 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3759         set_opt(sb, POSIX_ACL);
3760 #endif
3761         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3762         if (ext4_has_metadata_csum(sb))
3763                 set_opt(sb, JOURNAL_CHECKSUM);
3764
3765         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3766                 set_opt(sb, JOURNAL_DATA);
3767         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3768                 set_opt(sb, ORDERED_DATA);
3769         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3770                 set_opt(sb, WRITEBACK_DATA);
3771
3772         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3773                 set_opt(sb, ERRORS_PANIC);
3774         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3775                 set_opt(sb, ERRORS_CONT);
3776         else
3777                 set_opt(sb, ERRORS_RO);
3778         /* block_validity enabled by default; disable with noblock_validity */
3779         set_opt(sb, BLOCK_VALIDITY);
3780         if (def_mount_opts & EXT4_DEFM_DISCARD)
3781                 set_opt(sb, DISCARD);
3782
3783         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3784         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3785         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3786         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3787         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3788
3789         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3790                 set_opt(sb, BARRIER);
3791
3792         /*
3793          * enable delayed allocation by default
3794          * Use -o nodelalloc to turn it off
3795          */
3796         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3797             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3798                 set_opt(sb, DELALLOC);
3799
3800         /*
3801          * set default s_li_wait_mult for lazyinit, for the case there is
3802          * no mount option specified.
3803          */
3804         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3805
3806         if (sbi->s_es->s_mount_opts[0]) {
3807                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3808                                               sizeof(sbi->s_es->s_mount_opts),
3809                                               GFP_KERNEL);
3810                 if (!s_mount_opts)
3811                         goto failed_mount;
3812                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
3813                                    &journal_ioprio, 0)) {
3814                         ext4_msg(sb, KERN_WARNING,
3815                                  "failed to parse options in superblock: %s",
3816                                  s_mount_opts);
3817                 }
3818                 kfree(s_mount_opts);
3819         }
3820         sbi->s_def_mount_opt = sbi->s_mount_opt;
3821         if (!parse_options((char *) data, sb, &journal_devnum,
3822                            &journal_ioprio, 0))
3823                 goto failed_mount;
3824
3825 #ifdef CONFIG_UNICODE
3826         if (ext4_has_feature_casefold(sb) && !sbi->s_encoding) {
3827                 const struct ext4_sb_encodings *encoding_info;
3828                 struct unicode_map *encoding;
3829                 __u16 encoding_flags;
3830
3831                 if (ext4_has_feature_encrypt(sb)) {
3832                         ext4_msg(sb, KERN_ERR,
3833                                  "Can't mount with encoding and encryption");
3834                         goto failed_mount;
3835                 }
3836
3837                 if (ext4_sb_read_encoding(es, &encoding_info,
3838                                           &encoding_flags)) {
3839                         ext4_msg(sb, KERN_ERR,
3840                                  "Encoding requested by superblock is unknown");
3841                         goto failed_mount;
3842                 }
3843
3844                 encoding = utf8_load(encoding_info->version);
3845                 if (IS_ERR(encoding)) {
3846                         ext4_msg(sb, KERN_ERR,
3847                                  "can't mount with superblock charset: %s-%s "
3848                                  "not supported by the kernel. flags: 0x%x.",
3849                                  encoding_info->name, encoding_info->version,
3850                                  encoding_flags);
3851                         goto failed_mount;
3852                 }
3853                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
3854                          "%s-%s with flags 0x%hx", encoding_info->name,
3855                          encoding_info->version?:"\b", encoding_flags);
3856
3857                 sbi->s_encoding = encoding;
3858                 sbi->s_encoding_flags = encoding_flags;
3859         }
3860 #endif
3861
3862         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3863                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3864                             "with data=journal disables delayed "
3865                             "allocation and O_DIRECT support!\n");
3866                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3867                         ext4_msg(sb, KERN_ERR, "can't mount with "
3868                                  "both data=journal and delalloc");
3869                         goto failed_mount;
3870                 }
3871                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3872                         ext4_msg(sb, KERN_ERR, "can't mount with "
3873                                  "both data=journal and dioread_nolock");
3874                         goto failed_mount;
3875                 }
3876                 if (test_opt(sb, DAX)) {
3877                         ext4_msg(sb, KERN_ERR, "can't mount with "
3878                                  "both data=journal and dax");
3879                         goto failed_mount;
3880                 }
3881                 if (ext4_has_feature_encrypt(sb)) {
3882                         ext4_msg(sb, KERN_WARNING,
3883                                  "encrypted files will use data=ordered "
3884                                  "instead of data journaling mode");
3885                 }
3886                 if (test_opt(sb, DELALLOC))
3887                         clear_opt(sb, DELALLOC);
3888         } else {
3889                 sb->s_iflags |= SB_I_CGROUPWB;
3890         }
3891
3892         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
3893                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
3894
3895         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3896             (ext4_has_compat_features(sb) ||
3897              ext4_has_ro_compat_features(sb) ||
3898              ext4_has_incompat_features(sb)))
3899                 ext4_msg(sb, KERN_WARNING,
3900                        "feature flags set on rev 0 fs, "
3901                        "running e2fsck is recommended");
3902
3903         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3904                 set_opt2(sb, HURD_COMPAT);
3905                 if (ext4_has_feature_64bit(sb)) {
3906                         ext4_msg(sb, KERN_ERR,
3907                                  "The Hurd can't support 64-bit file systems");
3908                         goto failed_mount;
3909                 }
3910
3911                 /*
3912                  * ea_inode feature uses l_i_version field which is not
3913                  * available in HURD_COMPAT mode.
3914                  */
3915                 if (ext4_has_feature_ea_inode(sb)) {
3916                         ext4_msg(sb, KERN_ERR,
3917                                  "ea_inode feature is not supported for Hurd");
3918                         goto failed_mount;
3919                 }
3920         }
3921
3922         if (IS_EXT2_SB(sb)) {
3923                 if (ext2_feature_set_ok(sb))
3924                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3925                                  "using the ext4 subsystem");
3926                 else {
3927                         /*
3928                          * If we're probing be silent, if this looks like
3929                          * it's actually an ext[34] filesystem.
3930                          */
3931                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3932                                 goto failed_mount;
3933                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3934                                  "to feature incompatibilities");
3935                         goto failed_mount;
3936                 }
3937         }
3938
3939         if (IS_EXT3_SB(sb)) {
3940                 if (ext3_feature_set_ok(sb))
3941                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3942                                  "using the ext4 subsystem");
3943                 else {
3944                         /*
3945                          * If we're probing be silent, if this looks like
3946                          * it's actually an ext4 filesystem.
3947                          */
3948                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3949                                 goto failed_mount;
3950                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3951                                  "to feature incompatibilities");
3952                         goto failed_mount;
3953                 }
3954         }
3955
3956         /*
3957          * Check feature flags regardless of the revision level, since we
3958          * previously didn't change the revision level when setting the flags,
3959          * so there is a chance incompat flags are set on a rev 0 filesystem.
3960          */
3961         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
3962                 goto failed_mount;
3963
3964         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3965         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3966             blocksize > EXT4_MAX_BLOCK_SIZE) {
3967                 ext4_msg(sb, KERN_ERR,
3968                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3969                          blocksize, le32_to_cpu(es->s_log_block_size));
3970                 goto failed_mount;
3971         }
3972         if (le32_to_cpu(es->s_log_block_size) >
3973             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3974                 ext4_msg(sb, KERN_ERR,
3975                          "Invalid log block size: %u",
3976                          le32_to_cpu(es->s_log_block_size));
3977                 goto failed_mount;
3978         }
3979         if (le32_to_cpu(es->s_log_cluster_size) >
3980             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3981                 ext4_msg(sb, KERN_ERR,
3982                          "Invalid log cluster size: %u",
3983                          le32_to_cpu(es->s_log_cluster_size));
3984                 goto failed_mount;
3985         }
3986
3987         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
3988                 ext4_msg(sb, KERN_ERR,
3989                          "Number of reserved GDT blocks insanely large: %d",
3990                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
3991                 goto failed_mount;
3992         }
3993
3994         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3995                 if (ext4_has_feature_inline_data(sb)) {
3996                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
3997                                         " that may contain inline data");
3998                         goto failed_mount;
3999                 }
4000                 if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
4001                         ext4_msg(sb, KERN_ERR,
4002                                 "DAX unsupported by block device.");
4003                         goto failed_mount;
4004                 }
4005         }
4006
4007         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4008                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4009                          es->s_encryption_level);
4010                 goto failed_mount;
4011         }
4012
4013         if (sb->s_blocksize != blocksize) {
4014                 /* Validate the filesystem blocksize */
4015                 if (!sb_set_blocksize(sb, blocksize)) {
4016                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4017                                         blocksize);
4018                         goto failed_mount;
4019                 }
4020
4021                 brelse(bh);
4022                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4023                 offset = do_div(logical_sb_block, blocksize);
4024                 bh = sb_bread_unmovable(sb, logical_sb_block);
4025                 if (!bh) {
4026                         ext4_msg(sb, KERN_ERR,
4027                                "Can't read superblock on 2nd try");
4028                         goto failed_mount;
4029                 }
4030                 es = (struct ext4_super_block *)(bh->b_data + offset);
4031                 sbi->s_es = es;
4032                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4033                         ext4_msg(sb, KERN_ERR,
4034                                "Magic mismatch, very weird!");
4035                         goto failed_mount;
4036                 }
4037         }
4038
4039         has_huge_files = ext4_has_feature_huge_file(sb);
4040         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4041                                                       has_huge_files);
4042         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4043
4044         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4045                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4046                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4047         } else {
4048                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4049                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4050                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4051                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4052                                  sbi->s_first_ino);
4053                         goto failed_mount;
4054                 }
4055                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4056                     (!is_power_of_2(sbi->s_inode_size)) ||
4057                     (sbi->s_inode_size > blocksize)) {
4058                         ext4_msg(sb, KERN_ERR,
4059                                "unsupported inode size: %d",
4060                                sbi->s_inode_size);
4061                         goto failed_mount;
4062                 }
4063                 /*
4064                  * i_atime_extra is the last extra field available for [acm]times in
4065                  * struct ext4_inode. Checking for that field should suffice to ensure
4066                  * we have extra space for all three.
4067                  */
4068                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4069                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4070                         sb->s_time_gran = 1;
4071                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4072                 } else {
4073                         sb->s_time_gran = NSEC_PER_SEC;
4074                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4075                 }
4076
4077                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4078         }
4079
4080         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4081         if (ext4_has_feature_64bit(sb)) {
4082                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4083                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4084                     !is_power_of_2(sbi->s_desc_size)) {
4085                         ext4_msg(sb, KERN_ERR,
4086                                "unsupported descriptor size %lu",
4087                                sbi->s_desc_size);
4088                         goto failed_mount;
4089                 }
4090         } else
4091                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4092
4093         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4094         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4095
4096         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4097         if (sbi->s_inodes_per_block == 0)
4098                 goto cantfind_ext4;
4099         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4100             sbi->s_inodes_per_group > blocksize * 8) {
4101                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4102                          sbi->s_blocks_per_group);
4103                 goto failed_mount;
4104         }
4105         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4106                                         sbi->s_inodes_per_block;
4107         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4108         sbi->s_sbh = bh;
4109         sbi->s_mount_state = le16_to_cpu(es->s_state);
4110         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4111         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4112
4113         for (i = 0; i < 4; i++)
4114                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4115         sbi->s_def_hash_version = es->s_def_hash_version;
4116         if (ext4_has_feature_dir_index(sb)) {
4117                 i = le32_to_cpu(es->s_flags);
4118                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4119                         sbi->s_hash_unsigned = 3;
4120                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4121 #ifdef __CHAR_UNSIGNED__
4122                         if (!sb_rdonly(sb))
4123                                 es->s_flags |=
4124                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4125                         sbi->s_hash_unsigned = 3;
4126 #else
4127                         if (!sb_rdonly(sb))
4128                                 es->s_flags |=
4129                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4130 #endif
4131                 }
4132         }
4133
4134         /* Handle clustersize */
4135         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4136         has_bigalloc = ext4_has_feature_bigalloc(sb);
4137         if (has_bigalloc) {
4138                 if (clustersize < blocksize) {
4139                         ext4_msg(sb, KERN_ERR,
4140                                  "cluster size (%d) smaller than "
4141                                  "block size (%d)", clustersize, blocksize);
4142                         goto failed_mount;
4143                 }
4144                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4145                         le32_to_cpu(es->s_log_block_size);
4146                 sbi->s_clusters_per_group =
4147                         le32_to_cpu(es->s_clusters_per_group);
4148                 if (sbi->s_clusters_per_group > blocksize * 8) {
4149                         ext4_msg(sb, KERN_ERR,
4150                                  "#clusters per group too big: %lu",
4151                                  sbi->s_clusters_per_group);
4152                         goto failed_mount;
4153                 }
4154                 if (sbi->s_blocks_per_group !=
4155                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4156                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4157                                  "clusters per group (%lu) inconsistent",
4158                                  sbi->s_blocks_per_group,
4159                                  sbi->s_clusters_per_group);
4160                         goto failed_mount;
4161                 }
4162         } else {
4163                 if (clustersize != blocksize) {
4164                         ext4_msg(sb, KERN_ERR,
4165                                  "fragment/cluster size (%d) != "
4166                                  "block size (%d)", clustersize, blocksize);
4167                         goto failed_mount;
4168                 }
4169                 if (sbi->s_blocks_per_group > blocksize * 8) {
4170                         ext4_msg(sb, KERN_ERR,
4171                                  "#blocks per group too big: %lu",
4172                                  sbi->s_blocks_per_group);
4173                         goto failed_mount;
4174                 }
4175                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4176                 sbi->s_cluster_bits = 0;
4177         }
4178         sbi->s_cluster_ratio = clustersize / blocksize;
4179
4180         /* Do we have standard group size of clustersize * 8 blocks ? */
4181         if (sbi->s_blocks_per_group == clustersize << 3)
4182                 set_opt2(sb, STD_GROUP_SIZE);
4183
4184         /*
4185          * Test whether we have more sectors than will fit in sector_t,
4186          * and whether the max offset is addressable by the page cache.
4187          */
4188         err = generic_check_addressable(sb->s_blocksize_bits,
4189                                         ext4_blocks_count(es));
4190         if (err) {
4191                 ext4_msg(sb, KERN_ERR, "filesystem"
4192                          " too large to mount safely on this system");
4193                 goto failed_mount;
4194         }
4195
4196         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4197                 goto cantfind_ext4;
4198
4199         /* check blocks count against device size */
4200         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4201         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4202                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4203                        "exceeds size of device (%llu blocks)",
4204                        ext4_blocks_count(es), blocks_count);
4205                 goto failed_mount;
4206         }
4207
4208         /*
4209          * It makes no sense for the first data block to be beyond the end
4210          * of the filesystem.
4211          */
4212         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4213                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4214                          "block %u is beyond end of filesystem (%llu)",
4215                          le32_to_cpu(es->s_first_data_block),
4216                          ext4_blocks_count(es));
4217                 goto failed_mount;
4218         }
4219         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4220             (sbi->s_cluster_ratio == 1)) {
4221                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4222                          "block is 0 with a 1k block and cluster size");
4223                 goto failed_mount;
4224         }
4225
4226         blocks_count = (ext4_blocks_count(es) -
4227                         le32_to_cpu(es->s_first_data_block) +
4228                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4229         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4230         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4231                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
4232                        "(block count %llu, first data block %u, "
4233                        "blocks per group %lu)", sbi->s_groups_count,
4234                        ext4_blocks_count(es),
4235                        le32_to_cpu(es->s_first_data_block),
4236                        EXT4_BLOCKS_PER_GROUP(sb));
4237                 goto failed_mount;
4238         }
4239         sbi->s_groups_count = blocks_count;
4240         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4241                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4242         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4243             le32_to_cpu(es->s_inodes_count)) {
4244                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4245                          le32_to_cpu(es->s_inodes_count),
4246                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4247                 ret = -EINVAL;
4248                 goto failed_mount;
4249         }
4250         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4251                    EXT4_DESC_PER_BLOCK(sb);
4252         if (ext4_has_feature_meta_bg(sb)) {
4253                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4254                         ext4_msg(sb, KERN_WARNING,
4255                                  "first meta block group too large: %u "
4256                                  "(group descriptor block count %u)",
4257                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4258                         goto failed_mount;
4259                 }
4260         }
4261         sbi->s_group_desc = kvmalloc_array(db_count,
4262                                            sizeof(struct buffer_head *),
4263                                            GFP_KERNEL);
4264         if (sbi->s_group_desc == NULL) {
4265                 ext4_msg(sb, KERN_ERR, "not enough memory");
4266                 ret = -ENOMEM;
4267                 goto failed_mount;
4268         }
4269
4270         bgl_lock_init(sbi->s_blockgroup_lock);
4271
4272         /* Pre-read the descriptors into the buffer cache */
4273         for (i = 0; i < db_count; i++) {
4274                 block = descriptor_loc(sb, logical_sb_block, i);
4275                 sb_breadahead(sb, block);
4276         }
4277
4278         for (i = 0; i < db_count; i++) {
4279                 block = descriptor_loc(sb, logical_sb_block, i);
4280                 sbi->s_group_desc[i] = sb_bread_unmovable(sb, block);
4281                 if (!sbi->s_group_desc[i]) {
4282                         ext4_msg(sb, KERN_ERR,
4283                                "can't read group descriptor %d", i);
4284                         db_count = i;
4285                         goto failed_mount2;
4286                 }
4287         }
4288         sbi->s_gdb_count = db_count;
4289         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4290                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4291                 ret = -EFSCORRUPTED;
4292                 goto failed_mount2;
4293         }
4294
4295         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4296
4297         /* Register extent status tree shrinker */
4298         if (ext4_es_register_shrinker(sbi))
4299                 goto failed_mount3;
4300
4301         sbi->s_stripe = ext4_get_stripe_size(sbi);
4302         sbi->s_extent_max_zeroout_kb = 32;
4303
4304         /*
4305          * set up enough so that it can read an inode
4306          */
4307         sb->s_op = &ext4_sops;
4308         sb->s_export_op = &ext4_export_ops;
4309         sb->s_xattr = ext4_xattr_handlers;
4310 #ifdef CONFIG_FS_ENCRYPTION
4311         sb->s_cop = &ext4_cryptops;
4312 #endif
4313 #ifdef CONFIG_FS_VERITY
4314         sb->s_vop = &ext4_verityops;
4315 #endif
4316 #ifdef CONFIG_QUOTA
4317         sb->dq_op = &ext4_quota_operations;
4318         if (ext4_has_feature_quota(sb))
4319                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4320         else
4321                 sb->s_qcop = &ext4_qctl_operations;
4322         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4323 #endif
4324         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4325
4326         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4327         mutex_init(&sbi->s_orphan_lock);
4328
4329         sb->s_root = NULL;
4330
4331         needs_recovery = (es->s_last_orphan != 0 ||
4332                           ext4_has_feature_journal_needs_recovery(sb));
4333
4334         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4335                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4336                         goto failed_mount3a;
4337
4338         /*
4339          * The first inode we look at is the journal inode.  Don't try
4340          * root first: it may be modified in the journal!
4341          */
4342         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4343                 err = ext4_load_journal(sb, es, journal_devnum);
4344                 if (err)
4345                         goto failed_mount3a;
4346         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4347                    ext4_has_feature_journal_needs_recovery(sb)) {
4348                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4349                        "suppressed and not mounted read-only");
4350                 goto failed_mount_wq;
4351         } else {
4352                 /* Nojournal mode, all journal mount options are illegal */
4353                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4354                         ext4_msg(sb, KERN_ERR, "can't mount with "
4355                                  "journal_checksum, fs mounted w/o journal");
4356                         goto failed_mount_wq;
4357                 }
4358                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4359                         ext4_msg(sb, KERN_ERR, "can't mount with "
4360                                  "journal_async_commit, fs mounted w/o journal");
4361                         goto failed_mount_wq;
4362                 }
4363                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4364                         ext4_msg(sb, KERN_ERR, "can't mount with "
4365                                  "commit=%lu, fs mounted w/o journal",
4366                                  sbi->s_commit_interval / HZ);
4367                         goto failed_mount_wq;
4368                 }
4369                 if (EXT4_MOUNT_DATA_FLAGS &
4370                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4371                         ext4_msg(sb, KERN_ERR, "can't mount with "
4372                                  "data=, fs mounted w/o journal");
4373                         goto failed_mount_wq;
4374                 }
4375                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4376                 clear_opt(sb, JOURNAL_CHECKSUM);
4377                 clear_opt(sb, DATA_FLAGS);
4378                 sbi->s_journal = NULL;
4379                 needs_recovery = 0;
4380                 goto no_journal;
4381         }
4382
4383         if (ext4_has_feature_64bit(sb) &&
4384             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4385                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4386                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4387                 goto failed_mount_wq;
4388         }
4389
4390         if (!set_journal_csum_feature_set(sb)) {
4391                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4392                          "feature set");
4393                 goto failed_mount_wq;
4394         }
4395
4396         /* We have now updated the journal if required, so we can
4397          * validate the data journaling mode. */
4398         switch (test_opt(sb, DATA_FLAGS)) {
4399         case 0:
4400                 /* No mode set, assume a default based on the journal
4401                  * capabilities: ORDERED_DATA if the journal can
4402                  * cope, else JOURNAL_DATA
4403                  */
4404                 if (jbd2_journal_check_available_features
4405                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4406                         set_opt(sb, ORDERED_DATA);
4407                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4408                 } else {
4409                         set_opt(sb, JOURNAL_DATA);
4410                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4411                 }
4412                 break;
4413
4414         case EXT4_MOUNT_ORDERED_DATA:
4415         case EXT4_MOUNT_WRITEBACK_DATA:
4416                 if (!jbd2_journal_check_available_features
4417                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4418                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4419                                "requested data journaling mode");
4420                         goto failed_mount_wq;
4421                 }
4422         default:
4423                 break;
4424         }
4425
4426         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4427             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4428                 ext4_msg(sb, KERN_ERR, "can't mount with "
4429                         "journal_async_commit in data=ordered mode");
4430                 goto failed_mount_wq;
4431         }
4432
4433         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4434
4435         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4436
4437 no_journal:
4438         if (!test_opt(sb, NO_MBCACHE)) {
4439                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4440                 if (!sbi->s_ea_block_cache) {
4441                         ext4_msg(sb, KERN_ERR,
4442                                  "Failed to create ea_block_cache");
4443                         goto failed_mount_wq;
4444                 }
4445
4446                 if (ext4_has_feature_ea_inode(sb)) {
4447                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4448                         if (!sbi->s_ea_inode_cache) {
4449                                 ext4_msg(sb, KERN_ERR,
4450                                          "Failed to create ea_inode_cache");
4451                                 goto failed_mount_wq;
4452                         }
4453                 }
4454         }
4455
4456         if ((DUMMY_ENCRYPTION_ENABLED(sbi) || ext4_has_feature_encrypt(sb)) &&
4457             (blocksize != PAGE_SIZE)) {
4458                 ext4_msg(sb, KERN_ERR,
4459                          "Unsupported blocksize for fs encryption");
4460                 goto failed_mount_wq;
4461         }
4462
4463         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4464                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4465                 goto failed_mount_wq;
4466         }
4467
4468         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4469             !ext4_has_feature_encrypt(sb)) {
4470                 ext4_set_feature_encrypt(sb);
4471                 ext4_commit_super(sb, 1);
4472         }
4473
4474         /*
4475          * Get the # of file system overhead blocks from the
4476          * superblock if present.
4477          */
4478         if (es->s_overhead_clusters)
4479                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4480         else {
4481                 err = ext4_calculate_overhead(sb);
4482                 if (err)
4483                         goto failed_mount_wq;
4484         }
4485
4486         /*
4487          * The maximum number of concurrent works can be high and
4488          * concurrency isn't really necessary.  Limit it to 1.
4489          */
4490         EXT4_SB(sb)->rsv_conversion_wq =
4491                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4492         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4493                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4494                 ret = -ENOMEM;
4495                 goto failed_mount4;
4496         }
4497
4498         /*
4499          * The jbd2_journal_load will have done any necessary log recovery,
4500          * so we can safely mount the rest of the filesystem now.
4501          */
4502
4503         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4504         if (IS_ERR(root)) {
4505                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4506                 ret = PTR_ERR(root);
4507                 root = NULL;
4508                 goto failed_mount4;
4509         }
4510         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4511                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4512                 iput(root);
4513                 goto failed_mount4;
4514         }
4515
4516 #ifdef CONFIG_UNICODE
4517         if (sbi->s_encoding)
4518                 sb->s_d_op = &ext4_dentry_ops;
4519 #endif
4520
4521         sb->s_root = d_make_root(root);
4522         if (!sb->s_root) {
4523                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4524                 ret = -ENOMEM;
4525                 goto failed_mount4;
4526         }
4527
4528         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4529         if (ret == -EROFS) {
4530                 sb->s_flags |= SB_RDONLY;
4531                 ret = 0;
4532         } else if (ret)
4533                 goto failed_mount4a;
4534
4535         ext4_clamp_want_extra_isize(sb);
4536
4537         ext4_set_resv_clusters(sb);
4538
4539         err = ext4_setup_system_zone(sb);
4540         if (err) {
4541                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4542                          "zone (%d)", err);
4543                 goto failed_mount4a;
4544         }
4545
4546         ext4_ext_init(sb);
4547         err = ext4_mb_init(sb);
4548         if (err) {
4549                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4550                          err);
4551                 goto failed_mount5;
4552         }
4553
4554         block = ext4_count_free_clusters(sb);
4555         ext4_free_blocks_count_set(sbi->s_es,
4556                                    EXT4_C2B(sbi, block));
4557         ext4_superblock_csum_set(sb);
4558         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4559                                   GFP_KERNEL);
4560         if (!err) {
4561                 unsigned long freei = ext4_count_free_inodes(sb);
4562                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4563                 ext4_superblock_csum_set(sb);
4564                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4565                                           GFP_KERNEL);
4566         }
4567         if (!err)
4568                 err = percpu_counter_init(&sbi->s_dirs_counter,
4569                                           ext4_count_dirs(sb), GFP_KERNEL);
4570         if (!err)
4571                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4572                                           GFP_KERNEL);
4573         if (!err)
4574                 err = percpu_init_rwsem(&sbi->s_journal_flag_rwsem);
4575
4576         if (err) {
4577                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4578                 goto failed_mount6;
4579         }
4580
4581         if (ext4_has_feature_flex_bg(sb))
4582                 if (!ext4_fill_flex_info(sb)) {
4583                         ext4_msg(sb, KERN_ERR,
4584                                "unable to initialize "
4585                                "flex_bg meta info!");
4586                         goto failed_mount6;
4587                 }
4588
4589         err = ext4_register_li_request(sb, first_not_zeroed);
4590         if (err)
4591                 goto failed_mount6;
4592
4593         err = ext4_register_sysfs(sb);
4594         if (err)
4595                 goto failed_mount7;
4596
4597 #ifdef CONFIG_QUOTA
4598         /* Enable quota usage during mount. */
4599         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4600                 err = ext4_enable_quotas(sb);
4601                 if (err)
4602                         goto failed_mount8;
4603         }
4604 #endif  /* CONFIG_QUOTA */
4605
4606         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4607         ext4_orphan_cleanup(sb, es);
4608         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4609         if (needs_recovery) {
4610                 ext4_msg(sb, KERN_INFO, "recovery complete");
4611                 ext4_mark_recovery_complete(sb, es);
4612         }
4613         if (EXT4_SB(sb)->s_journal) {
4614                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4615                         descr = " journalled data mode";
4616                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4617                         descr = " ordered data mode";
4618                 else
4619                         descr = " writeback data mode";
4620         } else
4621                 descr = "out journal";
4622
4623         if (test_opt(sb, DISCARD)) {
4624                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4625                 if (!blk_queue_discard(q))
4626                         ext4_msg(sb, KERN_WARNING,
4627                                  "mounting with \"discard\" option, but "
4628                                  "the device does not support discard");
4629         }
4630
4631         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4632                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4633                          "Opts: %.*s%s%s", descr,
4634                          (int) sizeof(sbi->s_es->s_mount_opts),
4635                          sbi->s_es->s_mount_opts,
4636                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4637
4638         if (es->s_error_count)
4639                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4640
4641         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4642         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4643         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4644         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4645
4646         kfree(orig_data);
4647         return 0;
4648
4649 cantfind_ext4:
4650         if (!silent)
4651                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4652         goto failed_mount;
4653
4654 #ifdef CONFIG_QUOTA
4655 failed_mount8:
4656         ext4_unregister_sysfs(sb);
4657 #endif
4658 failed_mount7:
4659         ext4_unregister_li_request(sb);
4660 failed_mount6:
4661         ext4_mb_release(sb);
4662         if (sbi->s_flex_groups)
4663                 kvfree(sbi->s_flex_groups);
4664         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4665         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4666         percpu_counter_destroy(&sbi->s_dirs_counter);
4667         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4668         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
4669 failed_mount5:
4670         ext4_ext_release(sb);
4671         ext4_release_system_zone(sb);
4672 failed_mount4a:
4673         dput(sb->s_root);
4674         sb->s_root = NULL;
4675 failed_mount4:
4676         ext4_msg(sb, KERN_ERR, "mount failed");
4677         if (EXT4_SB(sb)->rsv_conversion_wq)
4678                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4679 failed_mount_wq:
4680         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4681         sbi->s_ea_inode_cache = NULL;
4682
4683         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4684         sbi->s_ea_block_cache = NULL;
4685
4686         if (sbi->s_journal) {
4687                 jbd2_journal_destroy(sbi->s_journal);
4688                 sbi->s_journal = NULL;
4689         }
4690 failed_mount3a:
4691         ext4_es_unregister_shrinker(sbi);
4692 failed_mount3:
4693         del_timer_sync(&sbi->s_err_report);
4694         if (sbi->s_mmp_tsk)
4695                 kthread_stop(sbi->s_mmp_tsk);
4696 failed_mount2:
4697         for (i = 0; i < db_count; i++)
4698                 brelse(sbi->s_group_desc[i]);
4699         kvfree(sbi->s_group_desc);
4700 failed_mount:
4701         if (sbi->s_chksum_driver)
4702                 crypto_free_shash(sbi->s_chksum_driver);
4703
4704 #ifdef CONFIG_UNICODE
4705         utf8_unload(sbi->s_encoding);
4706 #endif
4707
4708 #ifdef CONFIG_QUOTA
4709         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4710                 kfree(get_qf_name(sb, sbi, i));
4711 #endif
4712         ext4_blkdev_remove(sbi);
4713         brelse(bh);
4714 out_fail:
4715         sb->s_fs_info = NULL;
4716         kfree(sbi->s_blockgroup_lock);
4717 out_free_base:
4718         kfree(sbi);
4719         kfree(orig_data);
4720         fs_put_dax(dax_dev);
4721         return err ? err : ret;
4722 }
4723
4724 /*
4725  * Setup any per-fs journal parameters now.  We'll do this both on
4726  * initial mount, once the journal has been initialised but before we've
4727  * done any recovery; and again on any subsequent remount.
4728  */
4729 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4730 {
4731         struct ext4_sb_info *sbi = EXT4_SB(sb);
4732
4733         journal->j_commit_interval = sbi->s_commit_interval;
4734         journal->j_min_batch_time = sbi->s_min_batch_time;
4735         journal->j_max_batch_time = sbi->s_max_batch_time;
4736
4737         write_lock(&journal->j_state_lock);
4738         if (test_opt(sb, BARRIER))
4739                 journal->j_flags |= JBD2_BARRIER;
4740         else
4741                 journal->j_flags &= ~JBD2_BARRIER;
4742         if (test_opt(sb, DATA_ERR_ABORT))
4743                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4744         else
4745                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4746         write_unlock(&journal->j_state_lock);
4747 }
4748
4749 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4750                                              unsigned int journal_inum)
4751 {
4752         struct inode *journal_inode;
4753
4754         /*
4755          * Test for the existence of a valid inode on disk.  Bad things
4756          * happen if we iget() an unused inode, as the subsequent iput()
4757          * will try to delete it.
4758          */
4759         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
4760         if (IS_ERR(journal_inode)) {
4761                 ext4_msg(sb, KERN_ERR, "no journal found");
4762                 return NULL;
4763         }
4764         if (!journal_inode->i_nlink) {
4765                 make_bad_inode(journal_inode);
4766                 iput(journal_inode);
4767                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4768                 return NULL;
4769         }
4770
4771         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4772                   journal_inode, journal_inode->i_size);
4773         if (!S_ISREG(journal_inode->i_mode)) {
4774                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4775                 iput(journal_inode);
4776                 return NULL;
4777         }
4778         return journal_inode;
4779 }
4780
4781 static journal_t *ext4_get_journal(struct super_block *sb,
4782                                    unsigned int journal_inum)
4783 {
4784         struct inode *journal_inode;
4785         journal_t *journal;
4786
4787         BUG_ON(!ext4_has_feature_journal(sb));
4788
4789         journal_inode = ext4_get_journal_inode(sb, journal_inum);
4790         if (!journal_inode)
4791                 return NULL;
4792
4793         journal = jbd2_journal_init_inode(journal_inode);
4794         if (!journal) {
4795                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4796                 iput(journal_inode);
4797                 return NULL;
4798         }
4799         journal->j_private = sb;
4800         ext4_init_journal_params(sb, journal);
4801         return journal;
4802 }
4803
4804 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4805                                        dev_t j_dev)
4806 {
4807         struct buffer_head *bh;
4808         journal_t *journal;
4809         ext4_fsblk_t start;
4810         ext4_fsblk_t len;
4811         int hblock, blocksize;
4812         ext4_fsblk_t sb_block;
4813         unsigned long offset;
4814         struct ext4_super_block *es;
4815         struct block_device *bdev;
4816
4817         BUG_ON(!ext4_has_feature_journal(sb));
4818
4819         bdev = ext4_blkdev_get(j_dev, sb);
4820         if (bdev == NULL)
4821                 return NULL;
4822
4823         blocksize = sb->s_blocksize;
4824         hblock = bdev_logical_block_size(bdev);
4825         if (blocksize < hblock) {
4826                 ext4_msg(sb, KERN_ERR,
4827                         "blocksize too small for journal device");
4828                 goto out_bdev;
4829         }
4830
4831         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4832         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4833         set_blocksize(bdev, blocksize);
4834         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4835                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4836                        "external journal");
4837                 goto out_bdev;
4838         }
4839
4840         es = (struct ext4_super_block *) (bh->b_data + offset);
4841         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4842             !(le32_to_cpu(es->s_feature_incompat) &
4843               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4844                 ext4_msg(sb, KERN_ERR, "external journal has "
4845                                         "bad superblock");
4846                 brelse(bh);
4847                 goto out_bdev;
4848         }
4849
4850         if ((le32_to_cpu(es->s_feature_ro_compat) &
4851              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4852             es->s_checksum != ext4_superblock_csum(sb, es)) {
4853                 ext4_msg(sb, KERN_ERR, "external journal has "
4854                                        "corrupt superblock");
4855                 brelse(bh);
4856                 goto out_bdev;
4857         }
4858
4859         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4860                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4861                 brelse(bh);
4862                 goto out_bdev;
4863         }
4864
4865         len = ext4_blocks_count(es);
4866         start = sb_block + 1;
4867         brelse(bh);     /* we're done with the superblock */
4868
4869         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4870                                         start, len, blocksize);
4871         if (!journal) {
4872                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4873                 goto out_bdev;
4874         }
4875         journal->j_private = sb;
4876         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4877         wait_on_buffer(journal->j_sb_buffer);
4878         if (!buffer_uptodate(journal->j_sb_buffer)) {
4879                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4880                 goto out_journal;
4881         }
4882         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4883                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4884                                         "user (unsupported) - %d",
4885                         be32_to_cpu(journal->j_superblock->s_nr_users));
4886                 goto out_journal;
4887         }
4888         EXT4_SB(sb)->journal_bdev = bdev;
4889         ext4_init_journal_params(sb, journal);
4890         return journal;
4891
4892 out_journal:
4893         jbd2_journal_destroy(journal);
4894 out_bdev:
4895         ext4_blkdev_put(bdev);
4896         return NULL;
4897 }
4898
4899 static int ext4_load_journal(struct super_block *sb,
4900                              struct ext4_super_block *es,
4901                              unsigned long journal_devnum)
4902 {
4903         journal_t *journal;
4904         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4905         dev_t journal_dev;
4906         int err = 0;
4907         int really_read_only;
4908
4909         BUG_ON(!ext4_has_feature_journal(sb));
4910
4911         if (journal_devnum &&
4912             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4913                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4914                         "numbers have changed");
4915                 journal_dev = new_decode_dev(journal_devnum);
4916         } else
4917                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4918
4919         really_read_only = bdev_read_only(sb->s_bdev);
4920
4921         /*
4922          * Are we loading a blank journal or performing recovery after a
4923          * crash?  For recovery, we need to check in advance whether we
4924          * can get read-write access to the device.
4925          */
4926         if (ext4_has_feature_journal_needs_recovery(sb)) {
4927                 if (sb_rdonly(sb)) {
4928                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4929                                         "required on readonly filesystem");
4930                         if (really_read_only) {
4931                                 ext4_msg(sb, KERN_ERR, "write access "
4932                                         "unavailable, cannot proceed "
4933                                         "(try mounting with noload)");
4934                                 return -EROFS;
4935                         }
4936                         ext4_msg(sb, KERN_INFO, "write access will "
4937                                "be enabled during recovery");
4938                 }
4939         }
4940
4941         if (journal_inum && journal_dev) {
4942                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4943                        "and inode journals!");
4944                 return -EINVAL;
4945         }
4946
4947         if (journal_inum) {
4948                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4949                         return -EINVAL;
4950         } else {
4951                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4952                         return -EINVAL;
4953         }
4954
4955         if (!(journal->j_flags & JBD2_BARRIER))
4956                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4957
4958         if (!ext4_has_feature_journal_needs_recovery(sb))
4959                 err = jbd2_journal_wipe(journal, !really_read_only);
4960         if (!err) {
4961                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4962                 if (save)
4963                         memcpy(save, ((char *) es) +
4964                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4965                 err = jbd2_journal_load(journal);
4966                 if (save)
4967                         memcpy(((char *) es) + EXT4_S_ERR_START,
4968                                save, EXT4_S_ERR_LEN);
4969                 kfree(save);
4970         }
4971
4972         if (err) {
4973                 ext4_msg(sb, KERN_ERR, "error loading journal");
4974                 jbd2_journal_destroy(journal);
4975                 return err;
4976         }
4977
4978         EXT4_SB(sb)->s_journal = journal;
4979         ext4_clear_journal_err(sb, es);
4980
4981         if (!really_read_only && journal_devnum &&
4982             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4983                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4984
4985                 /* Make sure we flush the recovery flag to disk. */
4986                 ext4_commit_super(sb, 1);
4987         }
4988
4989         return 0;
4990 }
4991
4992 static int ext4_commit_super(struct super_block *sb, int sync)
4993 {
4994         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4995         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4996         int error = 0;
4997
4998         if (!sbh || block_device_ejected(sb))
4999                 return error;
5000
5001         /*
5002          * The superblock bh should be mapped, but it might not be if the
5003          * device was hot-removed. Not much we can do but fail the I/O.
5004          */
5005         if (!buffer_mapped(sbh))
5006                 return error;
5007
5008         /*
5009          * If the file system is mounted read-only, don't update the
5010          * superblock write time.  This avoids updating the superblock
5011          * write time when we are mounting the root file system
5012          * read/only but we need to replay the journal; at that point,
5013          * for people who are east of GMT and who make their clock
5014          * tick in localtime for Windows bug-for-bug compatibility,
5015          * the clock is set in the future, and this will cause e2fsck
5016          * to complain and force a full file system check.
5017          */
5018         if (!(sb->s_flags & SB_RDONLY))
5019                 ext4_update_tstamp(es, s_wtime);
5020         if (sb->s_bdev->bd_part)
5021                 es->s_kbytes_written =
5022                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5023                             ((part_stat_read(sb->s_bdev->bd_part,
5024                                              sectors[STAT_WRITE]) -
5025                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
5026         else
5027                 es->s_kbytes_written =
5028                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5029         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5030                 ext4_free_blocks_count_set(es,
5031                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5032                                 &EXT4_SB(sb)->s_freeclusters_counter)));
5033         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5034                 es->s_free_inodes_count =
5035                         cpu_to_le32(percpu_counter_sum_positive(
5036                                 &EXT4_SB(sb)->s_freeinodes_counter));
5037         BUFFER_TRACE(sbh, "marking dirty");
5038         ext4_superblock_csum_set(sb);
5039         if (sync)
5040                 lock_buffer(sbh);
5041         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5042                 /*
5043                  * Oh, dear.  A previous attempt to write the
5044                  * superblock failed.  This could happen because the
5045                  * USB device was yanked out.  Or it could happen to
5046                  * be a transient write error and maybe the block will
5047                  * be remapped.  Nothing we can do but to retry the
5048                  * write and hope for the best.
5049                  */
5050                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5051                        "superblock detected");
5052                 clear_buffer_write_io_error(sbh);
5053                 set_buffer_uptodate(sbh);
5054         }
5055         mark_buffer_dirty(sbh);
5056         if (sync) {
5057                 unlock_buffer(sbh);
5058                 error = __sync_dirty_buffer(sbh,
5059                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5060                 if (buffer_write_io_error(sbh)) {
5061                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5062                                "superblock");
5063                         clear_buffer_write_io_error(sbh);
5064                         set_buffer_uptodate(sbh);
5065                 }
5066         }
5067         return error;
5068 }
5069
5070 /*
5071  * Have we just finished recovery?  If so, and if we are mounting (or
5072  * remounting) the filesystem readonly, then we will end up with a
5073  * consistent fs on disk.  Record that fact.
5074  */
5075 static void ext4_mark_recovery_complete(struct super_block *sb,
5076                                         struct ext4_super_block *es)
5077 {
5078         journal_t *journal = EXT4_SB(sb)->s_journal;
5079
5080         if (!ext4_has_feature_journal(sb)) {
5081                 BUG_ON(journal != NULL);
5082                 return;
5083         }
5084         jbd2_journal_lock_updates(journal);
5085         if (jbd2_journal_flush(journal) < 0)
5086                 goto out;
5087
5088         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5089                 ext4_clear_feature_journal_needs_recovery(sb);
5090                 ext4_commit_super(sb, 1);
5091         }
5092
5093 out:
5094         jbd2_journal_unlock_updates(journal);
5095 }
5096
5097 /*
5098  * If we are mounting (or read-write remounting) a filesystem whose journal
5099  * has recorded an error from a previous lifetime, move that error to the
5100  * main filesystem now.
5101  */
5102 static void ext4_clear_journal_err(struct super_block *sb,
5103                                    struct ext4_super_block *es)
5104 {
5105         journal_t *journal;
5106         int j_errno;
5107         const char *errstr;
5108
5109         BUG_ON(!ext4_has_feature_journal(sb));
5110
5111         journal = EXT4_SB(sb)->s_journal;
5112
5113         /*
5114          * Now check for any error status which may have been recorded in the
5115          * journal by a prior ext4_error() or ext4_abort()
5116          */
5117
5118         j_errno = jbd2_journal_errno(journal);
5119         if (j_errno) {
5120                 char nbuf[16];
5121
5122                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5123                 ext4_warning(sb, "Filesystem error recorded "
5124                              "from previous mount: %s", errstr);
5125                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5126
5127                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5128                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5129                 ext4_commit_super(sb, 1);
5130
5131                 jbd2_journal_clear_err(journal);
5132                 jbd2_journal_update_sb_errno(journal);
5133         }
5134 }
5135
5136 /*
5137  * Force the running and committing transactions to commit,
5138  * and wait on the commit.
5139  */
5140 int ext4_force_commit(struct super_block *sb)
5141 {
5142         journal_t *journal;
5143
5144         if (sb_rdonly(sb))
5145                 return 0;
5146
5147         journal = EXT4_SB(sb)->s_journal;
5148         return ext4_journal_force_commit(journal);
5149 }
5150
5151 static int ext4_sync_fs(struct super_block *sb, int wait)
5152 {
5153         int ret = 0;
5154         tid_t target;
5155         bool needs_barrier = false;
5156         struct ext4_sb_info *sbi = EXT4_SB(sb);
5157
5158         if (unlikely(ext4_forced_shutdown(sbi)))
5159                 return 0;
5160
5161         trace_ext4_sync_fs(sb, wait);
5162         flush_workqueue(sbi->rsv_conversion_wq);
5163         /*
5164          * Writeback quota in non-journalled quota case - journalled quota has
5165          * no dirty dquots
5166          */
5167         dquot_writeback_dquots(sb, -1);
5168         /*
5169          * Data writeback is possible w/o journal transaction, so barrier must
5170          * being sent at the end of the function. But we can skip it if
5171          * transaction_commit will do it for us.
5172          */
5173         if (sbi->s_journal) {
5174                 target = jbd2_get_latest_transaction(sbi->s_journal);
5175                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5176                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5177                         needs_barrier = true;
5178
5179                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5180                         if (wait)
5181                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5182                                                            target);
5183                 }
5184         } else if (wait && test_opt(sb, BARRIER))
5185                 needs_barrier = true;
5186         if (needs_barrier) {
5187                 int err;
5188                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
5189                 if (!ret)
5190                         ret = err;
5191         }
5192
5193         return ret;
5194 }
5195
5196 /*
5197  * LVM calls this function before a (read-only) snapshot is created.  This
5198  * gives us a chance to flush the journal completely and mark the fs clean.
5199  *
5200  * Note that only this function cannot bring a filesystem to be in a clean
5201  * state independently. It relies on upper layer to stop all data & metadata
5202  * modifications.
5203  */
5204 static int ext4_freeze(struct super_block *sb)
5205 {
5206         int error = 0;
5207         journal_t *journal;
5208
5209         if (sb_rdonly(sb))
5210                 return 0;
5211
5212         journal = EXT4_SB(sb)->s_journal;
5213
5214         if (journal) {
5215                 /* Now we set up the journal barrier. */
5216                 jbd2_journal_lock_updates(journal);
5217
5218                 /*
5219                  * Don't clear the needs_recovery flag if we failed to
5220                  * flush the journal.
5221                  */
5222                 error = jbd2_journal_flush(journal);
5223                 if (error < 0)
5224                         goto out;
5225
5226                 /* Journal blocked and flushed, clear needs_recovery flag. */
5227                 ext4_clear_feature_journal_needs_recovery(sb);
5228         }
5229
5230         error = ext4_commit_super(sb, 1);
5231 out:
5232         if (journal)
5233                 /* we rely on upper layer to stop further updates */
5234                 jbd2_journal_unlock_updates(journal);
5235         return error;
5236 }
5237
5238 /*
5239  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5240  * flag here, even though the filesystem is not technically dirty yet.
5241  */
5242 static int ext4_unfreeze(struct super_block *sb)
5243 {
5244         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5245                 return 0;
5246
5247         if (EXT4_SB(sb)->s_journal) {
5248                 /* Reset the needs_recovery flag before the fs is unlocked. */
5249                 ext4_set_feature_journal_needs_recovery(sb);
5250         }
5251
5252         ext4_commit_super(sb, 1);
5253         return 0;
5254 }
5255
5256 /*
5257  * Structure to save mount options for ext4_remount's benefit
5258  */
5259 struct ext4_mount_options {
5260         unsigned long s_mount_opt;
5261         unsigned long s_mount_opt2;
5262         kuid_t s_resuid;
5263         kgid_t s_resgid;
5264         unsigned long s_commit_interval;
5265         u32 s_min_batch_time, s_max_batch_time;
5266 #ifdef CONFIG_QUOTA
5267         int s_jquota_fmt;
5268         char *s_qf_names[EXT4_MAXQUOTAS];
5269 #endif
5270 };
5271
5272 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5273 {
5274         struct ext4_super_block *es;
5275         struct ext4_sb_info *sbi = EXT4_SB(sb);
5276         unsigned long old_sb_flags;
5277         struct ext4_mount_options old_opts;
5278         int enable_quota = 0;
5279         ext4_group_t g;
5280         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5281         int err = 0;
5282 #ifdef CONFIG_QUOTA
5283         int i, j;
5284         char *to_free[EXT4_MAXQUOTAS];
5285 #endif
5286         char *orig_data = kstrdup(data, GFP_KERNEL);
5287
5288         if (data && !orig_data)
5289                 return -ENOMEM;
5290
5291         /* Store the original options */
5292         old_sb_flags = sb->s_flags;
5293         old_opts.s_mount_opt = sbi->s_mount_opt;
5294         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5295         old_opts.s_resuid = sbi->s_resuid;
5296         old_opts.s_resgid = sbi->s_resgid;
5297         old_opts.s_commit_interval = sbi->s_commit_interval;
5298         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5299         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5300 #ifdef CONFIG_QUOTA
5301         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5302         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5303                 if (sbi->s_qf_names[i]) {
5304                         char *qf_name = get_qf_name(sb, sbi, i);
5305
5306                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5307                         if (!old_opts.s_qf_names[i]) {
5308                                 for (j = 0; j < i; j++)
5309                                         kfree(old_opts.s_qf_names[j]);
5310                                 kfree(orig_data);
5311                                 return -ENOMEM;
5312                         }
5313                 } else
5314                         old_opts.s_qf_names[i] = NULL;
5315 #endif
5316         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5317                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5318
5319         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5320                 err = -EINVAL;
5321                 goto restore_opts;
5322         }
5323
5324         ext4_clamp_want_extra_isize(sb);
5325
5326         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5327             test_opt(sb, JOURNAL_CHECKSUM)) {
5328                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5329                          "during remount not supported; ignoring");
5330                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5331         }
5332
5333         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5334                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5335                         ext4_msg(sb, KERN_ERR, "can't mount with "
5336                                  "both data=journal and delalloc");
5337                         err = -EINVAL;
5338                         goto restore_opts;
5339                 }
5340                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5341                         ext4_msg(sb, KERN_ERR, "can't mount with "
5342                                  "both data=journal and dioread_nolock");
5343                         err = -EINVAL;
5344                         goto restore_opts;
5345                 }
5346                 if (test_opt(sb, DAX)) {
5347                         ext4_msg(sb, KERN_ERR, "can't mount with "
5348                                  "both data=journal and dax");
5349                         err = -EINVAL;
5350                         goto restore_opts;
5351                 }
5352         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5353                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5354                         ext4_msg(sb, KERN_ERR, "can't mount with "
5355                                 "journal_async_commit in data=ordered mode");
5356                         err = -EINVAL;
5357                         goto restore_opts;
5358                 }
5359         }
5360
5361         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5362                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5363                 err = -EINVAL;
5364                 goto restore_opts;
5365         }
5366
5367         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
5368                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
5369                         "dax flag with busy inodes while remounting");
5370                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
5371         }
5372
5373         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5374                 ext4_abort(sb, "Abort forced by user");
5375
5376         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5377                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5378
5379         es = sbi->s_es;
5380
5381         if (sbi->s_journal) {
5382                 ext4_init_journal_params(sb, sbi->s_journal);
5383                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5384         }
5385
5386         if (*flags & SB_LAZYTIME)
5387                 sb->s_flags |= SB_LAZYTIME;
5388
5389         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5390                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5391                         err = -EROFS;
5392                         goto restore_opts;
5393                 }
5394
5395                 if (*flags & SB_RDONLY) {
5396                         err = sync_filesystem(sb);
5397                         if (err < 0)
5398                                 goto restore_opts;
5399                         err = dquot_suspend(sb, -1);
5400                         if (err < 0)
5401                                 goto restore_opts;
5402
5403                         /*
5404                          * First of all, the unconditional stuff we have to do
5405                          * to disable replay of the journal when we next remount
5406                          */
5407                         sb->s_flags |= SB_RDONLY;
5408
5409                         /*
5410                          * OK, test if we are remounting a valid rw partition
5411                          * readonly, and if so set the rdonly flag and then
5412                          * mark the partition as valid again.
5413                          */
5414                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5415                             (sbi->s_mount_state & EXT4_VALID_FS))
5416                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5417
5418                         if (sbi->s_journal)
5419                                 ext4_mark_recovery_complete(sb, es);
5420                         if (sbi->s_mmp_tsk)
5421                                 kthread_stop(sbi->s_mmp_tsk);
5422                 } else {
5423                         /* Make sure we can mount this feature set readwrite */
5424                         if (ext4_has_feature_readonly(sb) ||
5425                             !ext4_feature_set_ok(sb, 0)) {
5426                                 err = -EROFS;
5427                                 goto restore_opts;
5428                         }
5429                         /*
5430                          * Make sure the group descriptor checksums
5431                          * are sane.  If they aren't, refuse to remount r/w.
5432                          */
5433                         for (g = 0; g < sbi->s_groups_count; g++) {
5434                                 struct ext4_group_desc *gdp =
5435                                         ext4_get_group_desc(sb, g, NULL);
5436
5437                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5438                                         ext4_msg(sb, KERN_ERR,
5439                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5440                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5441                                                le16_to_cpu(gdp->bg_checksum));
5442                                         err = -EFSBADCRC;
5443                                         goto restore_opts;
5444                                 }
5445                         }
5446
5447                         /*
5448                          * If we have an unprocessed orphan list hanging
5449                          * around from a previously readonly bdev mount,
5450                          * require a full umount/remount for now.
5451                          */
5452                         if (es->s_last_orphan) {
5453                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5454                                        "remount RDWR because of unprocessed "
5455                                        "orphan inode list.  Please "
5456                                        "umount/remount instead");
5457                                 err = -EINVAL;
5458                                 goto restore_opts;
5459                         }
5460
5461                         /*
5462                          * Mounting a RDONLY partition read-write, so reread
5463                          * and store the current valid flag.  (It may have
5464                          * been changed by e2fsck since we originally mounted
5465                          * the partition.)
5466                          */
5467                         if (sbi->s_journal)
5468                                 ext4_clear_journal_err(sb, es);
5469                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5470
5471                         err = ext4_setup_super(sb, es, 0);
5472                         if (err)
5473                                 goto restore_opts;
5474
5475                         sb->s_flags &= ~SB_RDONLY;
5476                         if (ext4_has_feature_mmp(sb))
5477                                 if (ext4_multi_mount_protect(sb,
5478                                                 le64_to_cpu(es->s_mmp_block))) {
5479                                         err = -EROFS;
5480                                         goto restore_opts;
5481                                 }
5482                         enable_quota = 1;
5483                 }
5484         }
5485
5486         /*
5487          * Reinitialize lazy itable initialization thread based on
5488          * current settings
5489          */
5490         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5491                 ext4_unregister_li_request(sb);
5492         else {
5493                 ext4_group_t first_not_zeroed;
5494                 first_not_zeroed = ext4_has_uninit_itable(sb);
5495                 ext4_register_li_request(sb, first_not_zeroed);
5496         }
5497
5498         ext4_setup_system_zone(sb);
5499         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5500                 err = ext4_commit_super(sb, 1);
5501                 if (err)
5502                         goto restore_opts;
5503         }
5504
5505 #ifdef CONFIG_QUOTA
5506         /* Release old quota file names */
5507         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5508                 kfree(old_opts.s_qf_names[i]);
5509         if (enable_quota) {
5510                 if (sb_any_quota_suspended(sb))
5511                         dquot_resume(sb, -1);
5512                 else if (ext4_has_feature_quota(sb)) {
5513                         err = ext4_enable_quotas(sb);
5514                         if (err)
5515                                 goto restore_opts;
5516                 }
5517         }
5518 #endif
5519
5520         *flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME);
5521         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5522         kfree(orig_data);
5523         return 0;
5524
5525 restore_opts:
5526         sb->s_flags = old_sb_flags;
5527         sbi->s_mount_opt = old_opts.s_mount_opt;
5528         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5529         sbi->s_resuid = old_opts.s_resuid;
5530         sbi->s_resgid = old_opts.s_resgid;
5531         sbi->s_commit_interval = old_opts.s_commit_interval;
5532         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5533         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5534 #ifdef CONFIG_QUOTA
5535         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5536         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5537                 to_free[i] = get_qf_name(sb, sbi, i);
5538                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
5539         }
5540         synchronize_rcu();
5541         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5542                 kfree(to_free[i]);
5543 #endif
5544         kfree(orig_data);
5545         return err;
5546 }
5547
5548 #ifdef CONFIG_QUOTA
5549 static int ext4_statfs_project(struct super_block *sb,
5550                                kprojid_t projid, struct kstatfs *buf)
5551 {
5552         struct kqid qid;
5553         struct dquot *dquot;
5554         u64 limit;
5555         u64 curblock;
5556
5557         qid = make_kqid_projid(projid);
5558         dquot = dqget(sb, qid);
5559         if (IS_ERR(dquot))
5560                 return PTR_ERR(dquot);
5561         spin_lock(&dquot->dq_dqb_lock);
5562
5563         limit = (dquot->dq_dqb.dqb_bsoftlimit ?
5564                  dquot->dq_dqb.dqb_bsoftlimit :
5565                  dquot->dq_dqb.dqb_bhardlimit) >> sb->s_blocksize_bits;
5566         if (limit && buf->f_blocks > limit) {
5567                 curblock = (dquot->dq_dqb.dqb_curspace +
5568                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5569                 buf->f_blocks = limit;
5570                 buf->f_bfree = buf->f_bavail =
5571                         (buf->f_blocks > curblock) ?
5572                          (buf->f_blocks - curblock) : 0;
5573         }
5574
5575         limit = dquot->dq_dqb.dqb_isoftlimit ?
5576                 dquot->dq_dqb.dqb_isoftlimit :
5577                 dquot->dq_dqb.dqb_ihardlimit;
5578         if (limit && buf->f_files > limit) {
5579                 buf->f_files = limit;
5580                 buf->f_ffree =
5581                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5582                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5583         }
5584
5585         spin_unlock(&dquot->dq_dqb_lock);
5586         dqput(dquot);
5587         return 0;
5588 }
5589 #endif
5590
5591 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5592 {
5593         struct super_block *sb = dentry->d_sb;
5594         struct ext4_sb_info *sbi = EXT4_SB(sb);
5595         struct ext4_super_block *es = sbi->s_es;
5596         ext4_fsblk_t overhead = 0, resv_blocks;
5597         u64 fsid;
5598         s64 bfree;
5599         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5600
5601         if (!test_opt(sb, MINIX_DF))
5602                 overhead = sbi->s_overhead;
5603
5604         buf->f_type = EXT4_SUPER_MAGIC;
5605         buf->f_bsize = sb->s_blocksize;
5606         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5607         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5608                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5609         /* prevent underflow in case that few free space is available */
5610         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5611         buf->f_bavail = buf->f_bfree -
5612                         (ext4_r_blocks_count(es) + resv_blocks);
5613         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5614                 buf->f_bavail = 0;
5615         buf->f_files = le32_to_cpu(es->s_inodes_count);
5616         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5617         buf->f_namelen = EXT4_NAME_LEN;
5618         fsid = le64_to_cpup((void *)es->s_uuid) ^
5619                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5620         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5621         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5622
5623 #ifdef CONFIG_QUOTA
5624         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5625             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5626                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5627 #endif
5628         return 0;
5629 }
5630
5631
5632 #ifdef CONFIG_QUOTA
5633
5634 /*
5635  * Helper functions so that transaction is started before we acquire dqio_sem
5636  * to keep correct lock ordering of transaction > dqio_sem
5637  */
5638 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5639 {
5640         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5641 }
5642
5643 static int ext4_write_dquot(struct dquot *dquot)
5644 {
5645         int ret, err;
5646         handle_t *handle;
5647         struct inode *inode;
5648
5649         inode = dquot_to_inode(dquot);
5650         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5651                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5652         if (IS_ERR(handle))
5653                 return PTR_ERR(handle);
5654         ret = dquot_commit(dquot);
5655         err = ext4_journal_stop(handle);
5656         if (!ret)
5657                 ret = err;
5658         return ret;
5659 }
5660
5661 static int ext4_acquire_dquot(struct dquot *dquot)
5662 {
5663         int ret, err;
5664         handle_t *handle;
5665
5666         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5667                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5668         if (IS_ERR(handle))
5669                 return PTR_ERR(handle);
5670         ret = dquot_acquire(dquot);
5671         err = ext4_journal_stop(handle);
5672         if (!ret)
5673                 ret = err;
5674         return ret;
5675 }
5676
5677 static int ext4_release_dquot(struct dquot *dquot)
5678 {
5679         int ret, err;
5680         handle_t *handle;
5681
5682         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5683                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5684         if (IS_ERR(handle)) {
5685                 /* Release dquot anyway to avoid endless cycle in dqput() */
5686                 dquot_release(dquot);
5687                 return PTR_ERR(handle);
5688         }
5689         ret = dquot_release(dquot);
5690         err = ext4_journal_stop(handle);
5691         if (!ret)
5692                 ret = err;
5693         return ret;
5694 }
5695
5696 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5697 {
5698         struct super_block *sb = dquot->dq_sb;
5699         struct ext4_sb_info *sbi = EXT4_SB(sb);
5700
5701         /* Are we journaling quotas? */
5702         if (ext4_has_feature_quota(sb) ||
5703             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5704                 dquot_mark_dquot_dirty(dquot);
5705                 return ext4_write_dquot(dquot);
5706         } else {
5707                 return dquot_mark_dquot_dirty(dquot);
5708         }
5709 }
5710
5711 static int ext4_write_info(struct super_block *sb, int type)
5712 {
5713         int ret, err;
5714         handle_t *handle;
5715
5716         /* Data block + inode block */
5717         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5718         if (IS_ERR(handle))
5719                 return PTR_ERR(handle);
5720         ret = dquot_commit_info(sb, type);
5721         err = ext4_journal_stop(handle);
5722         if (!ret)
5723                 ret = err;
5724         return ret;
5725 }
5726
5727 /*
5728  * Turn on quotas during mount time - we need to find
5729  * the quota file and such...
5730  */
5731 static int ext4_quota_on_mount(struct super_block *sb, int type)
5732 {
5733         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
5734                                         EXT4_SB(sb)->s_jquota_fmt, type);
5735 }
5736
5737 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5738 {
5739         struct ext4_inode_info *ei = EXT4_I(inode);
5740
5741         /* The first argument of lockdep_set_subclass has to be
5742          * *exactly* the same as the argument to init_rwsem() --- in
5743          * this case, in init_once() --- or lockdep gets unhappy
5744          * because the name of the lock is set using the
5745          * stringification of the argument to init_rwsem().
5746          */
5747         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
5748         lockdep_set_subclass(&ei->i_data_sem, subclass);
5749 }
5750
5751 /*
5752  * Standard function to be called on quota_on
5753  */
5754 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5755                          const struct path *path)
5756 {
5757         int err;
5758
5759         if (!test_opt(sb, QUOTA))
5760                 return -EINVAL;
5761
5762         /* Quotafile not on the same filesystem? */
5763         if (path->dentry->d_sb != sb)
5764                 return -EXDEV;
5765         /* Journaling quota? */
5766         if (EXT4_SB(sb)->s_qf_names[type]) {
5767                 /* Quotafile not in fs root? */
5768                 if (path->dentry->d_parent != sb->s_root)
5769                         ext4_msg(sb, KERN_WARNING,
5770                                 "Quota file not on filesystem root. "
5771                                 "Journaled quota will not work");
5772                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5773         } else {
5774                 /*
5775                  * Clear the flag just in case mount options changed since
5776                  * last time.
5777                  */
5778                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5779         }
5780
5781         /*
5782          * When we journal data on quota file, we have to flush journal to see
5783          * all updates to the file when we bypass pagecache...
5784          */
5785         if (EXT4_SB(sb)->s_journal &&
5786             ext4_should_journal_data(d_inode(path->dentry))) {
5787                 /*
5788                  * We don't need to lock updates but journal_flush() could
5789                  * otherwise be livelocked...
5790                  */
5791                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5792                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5793                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5794                 if (err)
5795                         return err;
5796         }
5797
5798         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5799         err = dquot_quota_on(sb, type, format_id, path);
5800         if (err) {
5801                 lockdep_set_quota_inode(path->dentry->d_inode,
5802                                              I_DATA_SEM_NORMAL);
5803         } else {
5804                 struct inode *inode = d_inode(path->dentry);
5805                 handle_t *handle;
5806
5807                 /*
5808                  * Set inode flags to prevent userspace from messing with quota
5809                  * files. If this fails, we return success anyway since quotas
5810                  * are already enabled and this is not a hard failure.
5811                  */
5812                 inode_lock(inode);
5813                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5814                 if (IS_ERR(handle))
5815                         goto unlock_inode;
5816                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5817                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5818                                 S_NOATIME | S_IMMUTABLE);
5819                 ext4_mark_inode_dirty(handle, inode);
5820                 ext4_journal_stop(handle);
5821         unlock_inode:
5822                 inode_unlock(inode);
5823         }
5824         return err;
5825 }
5826
5827 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5828                              unsigned int flags)
5829 {
5830         int err;
5831         struct inode *qf_inode;
5832         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5833                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5834                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5835                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5836         };
5837
5838         BUG_ON(!ext4_has_feature_quota(sb));
5839
5840         if (!qf_inums[type])
5841                 return -EPERM;
5842
5843         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
5844         if (IS_ERR(qf_inode)) {
5845                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5846                 return PTR_ERR(qf_inode);
5847         }
5848
5849         /* Don't account quota for quota files to avoid recursion */
5850         qf_inode->i_flags |= S_NOQUOTA;
5851         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5852         err = dquot_enable(qf_inode, type, format_id, flags);
5853         if (err)
5854                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5855         iput(qf_inode);
5856
5857         return err;
5858 }
5859
5860 /* Enable usage tracking for all quota types. */
5861 static int ext4_enable_quotas(struct super_block *sb)
5862 {
5863         int type, err = 0;
5864         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5865                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5866                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5867                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5868         };
5869         bool quota_mopt[EXT4_MAXQUOTAS] = {
5870                 test_opt(sb, USRQUOTA),
5871                 test_opt(sb, GRPQUOTA),
5872                 test_opt(sb, PRJQUOTA),
5873         };
5874
5875         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
5876         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5877                 if (qf_inums[type]) {
5878                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5879                                 DQUOT_USAGE_ENABLED |
5880                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5881                         if (err) {
5882                                 ext4_warning(sb,
5883                                         "Failed to enable quota tracking "
5884                                         "(type=%d, err=%d). Please run "
5885                                         "e2fsck to fix.", type, err);
5886                                 for (type--; type >= 0; type--)
5887                                         dquot_quota_off(sb, type);
5888
5889                                 return err;
5890                         }
5891                 }
5892         }
5893         return 0;
5894 }
5895
5896 static int ext4_quota_off(struct super_block *sb, int type)
5897 {
5898         struct inode *inode = sb_dqopt(sb)->files[type];
5899         handle_t *handle;
5900         int err;
5901
5902         /* Force all delayed allocation blocks to be allocated.
5903          * Caller already holds s_umount sem */
5904         if (test_opt(sb, DELALLOC))
5905                 sync_filesystem(sb);
5906
5907         if (!inode || !igrab(inode))
5908                 goto out;
5909
5910         err = dquot_quota_off(sb, type);
5911         if (err || ext4_has_feature_quota(sb))
5912                 goto out_put;
5913
5914         inode_lock(inode);
5915         /*
5916          * Update modification times of quota files when userspace can
5917          * start looking at them. If we fail, we return success anyway since
5918          * this is not a hard failure and quotas are already disabled.
5919          */
5920         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5921         if (IS_ERR(handle))
5922                 goto out_unlock;
5923         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
5924         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
5925         inode->i_mtime = inode->i_ctime = current_time(inode);
5926         ext4_mark_inode_dirty(handle, inode);
5927         ext4_journal_stop(handle);
5928 out_unlock:
5929         inode_unlock(inode);
5930 out_put:
5931         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
5932         iput(inode);
5933         return err;
5934 out:
5935         return dquot_quota_off(sb, type);
5936 }
5937
5938 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5939  * acquiring the locks... As quota files are never truncated and quota code
5940  * itself serializes the operations (and no one else should touch the files)
5941  * we don't have to be afraid of races */
5942 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5943                                size_t len, loff_t off)
5944 {
5945         struct inode *inode = sb_dqopt(sb)->files[type];
5946         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5947         int offset = off & (sb->s_blocksize - 1);
5948         int tocopy;
5949         size_t toread;
5950         struct buffer_head *bh;
5951         loff_t i_size = i_size_read(inode);
5952
5953         if (off > i_size)
5954                 return 0;
5955         if (off+len > i_size)
5956                 len = i_size-off;
5957         toread = len;
5958         while (toread > 0) {
5959                 tocopy = sb->s_blocksize - offset < toread ?
5960                                 sb->s_blocksize - offset : toread;
5961                 bh = ext4_bread(NULL, inode, blk, 0);
5962                 if (IS_ERR(bh))
5963                         return PTR_ERR(bh);
5964                 if (!bh)        /* A hole? */
5965                         memset(data, 0, tocopy);
5966                 else
5967                         memcpy(data, bh->b_data+offset, tocopy);
5968                 brelse(bh);
5969                 offset = 0;
5970                 toread -= tocopy;
5971                 data += tocopy;
5972                 blk++;
5973         }
5974         return len;
5975 }
5976
5977 /* Write to quotafile (we know the transaction is already started and has
5978  * enough credits) */
5979 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5980                                 const char *data, size_t len, loff_t off)
5981 {
5982         struct inode *inode = sb_dqopt(sb)->files[type];
5983         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5984         int err, offset = off & (sb->s_blocksize - 1);
5985         int retries = 0;
5986         struct buffer_head *bh;
5987         handle_t *handle = journal_current_handle();
5988
5989         if (EXT4_SB(sb)->s_journal && !handle) {
5990                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5991                         " cancelled because transaction is not started",
5992                         (unsigned long long)off, (unsigned long long)len);
5993                 return -EIO;
5994         }
5995         /*
5996          * Since we account only one data block in transaction credits,
5997          * then it is impossible to cross a block boundary.
5998          */
5999         if (sb->s_blocksize - offset < len) {
6000                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6001                         " cancelled because not block aligned",
6002                         (unsigned long long)off, (unsigned long long)len);
6003                 return -EIO;
6004         }
6005
6006         do {
6007                 bh = ext4_bread(handle, inode, blk,
6008                                 EXT4_GET_BLOCKS_CREATE |
6009                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6010         } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
6011                  ext4_should_retry_alloc(inode->i_sb, &retries));
6012         if (IS_ERR(bh))
6013                 return PTR_ERR(bh);
6014         if (!bh)
6015                 goto out;
6016         BUFFER_TRACE(bh, "get write access");
6017         err = ext4_journal_get_write_access(handle, bh);
6018         if (err) {
6019                 brelse(bh);
6020                 return err;
6021         }
6022         lock_buffer(bh);
6023         memcpy(bh->b_data+offset, data, len);
6024         flush_dcache_page(bh->b_page);
6025         unlock_buffer(bh);
6026         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6027         brelse(bh);
6028 out:
6029         if (inode->i_size < off + len) {
6030                 i_size_write(inode, off + len);
6031                 EXT4_I(inode)->i_disksize = inode->i_size;
6032                 ext4_mark_inode_dirty(handle, inode);
6033         }
6034         return len;
6035 }
6036
6037 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid)
6038 {
6039         const struct quota_format_ops   *ops;
6040
6041         if (!sb_has_quota_loaded(sb, qid->type))
6042                 return -ESRCH;
6043         ops = sb_dqopt(sb)->ops[qid->type];
6044         if (!ops || !ops->get_next_id)
6045                 return -ENOSYS;
6046         return dquot_get_next_id(sb, qid);
6047 }
6048 #endif
6049
6050 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6051                        const char *dev_name, void *data)
6052 {
6053         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6054 }
6055
6056 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6057 static inline void register_as_ext2(void)
6058 {
6059         int err = register_filesystem(&ext2_fs_type);
6060         if (err)
6061                 printk(KERN_WARNING
6062                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6063 }
6064
6065 static inline void unregister_as_ext2(void)
6066 {
6067         unregister_filesystem(&ext2_fs_type);
6068 }
6069
6070 static inline int ext2_feature_set_ok(struct super_block *sb)
6071 {
6072         if (ext4_has_unknown_ext2_incompat_features(sb))
6073                 return 0;
6074         if (sb_rdonly(sb))
6075                 return 1;
6076         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6077                 return 0;
6078         return 1;
6079 }
6080 #else
6081 static inline void register_as_ext2(void) { }
6082 static inline void unregister_as_ext2(void) { }
6083 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6084 #endif
6085
6086 static inline void register_as_ext3(void)
6087 {
6088         int err = register_filesystem(&ext3_fs_type);
6089         if (err)
6090                 printk(KERN_WARNING
6091                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6092 }
6093
6094 static inline void unregister_as_ext3(void)
6095 {
6096         unregister_filesystem(&ext3_fs_type);
6097 }
6098
6099 static inline int ext3_feature_set_ok(struct super_block *sb)
6100 {
6101         if (ext4_has_unknown_ext3_incompat_features(sb))
6102                 return 0;
6103         if (!ext4_has_feature_journal(sb))
6104                 return 0;
6105         if (sb_rdonly(sb))
6106                 return 1;
6107         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6108                 return 0;
6109         return 1;
6110 }
6111
6112 static struct file_system_type ext4_fs_type = {
6113         .owner          = THIS_MODULE,
6114         .name           = "ext4",
6115         .mount          = ext4_mount,
6116         .kill_sb        = kill_block_super,
6117         .fs_flags       = FS_REQUIRES_DEV,
6118 };
6119 MODULE_ALIAS_FS("ext4");
6120
6121 /* Shared across all ext4 file systems */
6122 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6123
6124 static int __init ext4_init_fs(void)
6125 {
6126         int i, err;
6127
6128         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6129         ext4_li_info = NULL;
6130         mutex_init(&ext4_li_mtx);
6131
6132         /* Build-time check for flags consistency */
6133         ext4_check_flag_values();
6134
6135         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6136                 init_waitqueue_head(&ext4__ioend_wq[i]);
6137
6138         err = ext4_init_es();
6139         if (err)
6140                 return err;
6141
6142         err = ext4_init_pending();
6143         if (err)
6144                 goto out7;
6145
6146         err = ext4_init_post_read_processing();
6147         if (err)
6148                 goto out6;
6149
6150         err = ext4_init_pageio();
6151         if (err)
6152                 goto out5;
6153
6154         err = ext4_init_system_zone();
6155         if (err)
6156                 goto out4;
6157
6158         err = ext4_init_sysfs();
6159         if (err)
6160                 goto out3;
6161
6162         err = ext4_init_mballoc();
6163         if (err)
6164                 goto out2;
6165         err = init_inodecache();
6166         if (err)
6167                 goto out1;
6168         register_as_ext3();
6169         register_as_ext2();
6170         err = register_filesystem(&ext4_fs_type);
6171         if (err)
6172                 goto out;
6173
6174         return 0;
6175 out:
6176         unregister_as_ext2();
6177         unregister_as_ext3();
6178         destroy_inodecache();
6179 out1:
6180         ext4_exit_mballoc();
6181 out2:
6182         ext4_exit_sysfs();
6183 out3:
6184         ext4_exit_system_zone();
6185 out4:
6186         ext4_exit_pageio();
6187 out5:
6188         ext4_exit_post_read_processing();
6189 out6:
6190         ext4_exit_pending();
6191 out7:
6192         ext4_exit_es();
6193
6194         return err;
6195 }
6196
6197 static void __exit ext4_exit_fs(void)
6198 {
6199         ext4_destroy_lazyinit_thread();
6200         unregister_as_ext2();
6201         unregister_as_ext3();
6202         unregister_filesystem(&ext4_fs_type);
6203         destroy_inodecache();
6204         ext4_exit_mballoc();
6205         ext4_exit_sysfs();
6206         ext4_exit_system_zone();
6207         ext4_exit_pageio();
6208         ext4_exit_post_read_processing();
6209         ext4_exit_es();
6210         ext4_exit_pending();
6211 }
6212
6213 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6214 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6215 MODULE_LICENSE("GPL");
6216 MODULE_SOFTDEP("pre: crc32c");
6217 module_init(ext4_init_fs)
6218 module_exit(ext4_exit_fs)