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         trace_ext4_drop_inode(inode, drop);
1111         return drop;
1112 }
1113
1114 static void ext4_free_in_core_inode(struct inode *inode)
1115 {
1116         fscrypt_free_inode(inode);
1117         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1118 }
1119
1120 static void ext4_destroy_inode(struct inode *inode)
1121 {
1122         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1123                 ext4_msg(inode->i_sb, KERN_ERR,
1124                          "Inode %lu (%p): orphan list check failed!",
1125                          inode->i_ino, EXT4_I(inode));
1126                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1127                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1128                                 true);
1129                 dump_stack();
1130         }
1131 }
1132
1133 static void init_once(void *foo)
1134 {
1135         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1136
1137         INIT_LIST_HEAD(&ei->i_orphan);
1138         init_rwsem(&ei->xattr_sem);
1139         init_rwsem(&ei->i_data_sem);
1140         init_rwsem(&ei->i_mmap_sem);
1141         inode_init_once(&ei->vfs_inode);
1142 }
1143
1144 static int __init init_inodecache(void)
1145 {
1146         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1147                                 sizeof(struct ext4_inode_info), 0,
1148                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1149                                         SLAB_ACCOUNT),
1150                                 offsetof(struct ext4_inode_info, i_data),
1151                                 sizeof_field(struct ext4_inode_info, i_data),
1152                                 init_once);
1153         if (ext4_inode_cachep == NULL)
1154                 return -ENOMEM;
1155         return 0;
1156 }
1157
1158 static void destroy_inodecache(void)
1159 {
1160         /*
1161          * Make sure all delayed rcu free inodes are flushed before we
1162          * destroy cache.
1163          */
1164         rcu_barrier();
1165         kmem_cache_destroy(ext4_inode_cachep);
1166 }
1167
1168 void ext4_clear_inode(struct inode *inode)
1169 {
1170         invalidate_inode_buffers(inode);
1171         clear_inode(inode);
1172         dquot_drop(inode);
1173         ext4_discard_preallocations(inode);
1174         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1175         if (EXT4_I(inode)->jinode) {
1176                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1177                                                EXT4_I(inode)->jinode);
1178                 jbd2_free_inode(EXT4_I(inode)->jinode);
1179                 EXT4_I(inode)->jinode = NULL;
1180         }
1181         fscrypt_put_encryption_info(inode);
1182 }
1183
1184 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1185                                         u64 ino, u32 generation)
1186 {
1187         struct inode *inode;
1188
1189         /*
1190          * Currently we don't know the generation for parent directory, so
1191          * a generation of 0 means "accept any"
1192          */
1193         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1194         if (IS_ERR(inode))
1195                 return ERR_CAST(inode);
1196         if (generation && inode->i_generation != generation) {
1197                 iput(inode);
1198                 return ERR_PTR(-ESTALE);
1199         }
1200
1201         return inode;
1202 }
1203
1204 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1205                                         int fh_len, int fh_type)
1206 {
1207         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1208                                     ext4_nfs_get_inode);
1209 }
1210
1211 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1212                                         int fh_len, int fh_type)
1213 {
1214         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1215                                     ext4_nfs_get_inode);
1216 }
1217
1218 static int ext4_nfs_commit_metadata(struct inode *inode)
1219 {
1220         struct writeback_control wbc = {
1221                 .sync_mode = WB_SYNC_ALL
1222         };
1223
1224         trace_ext4_nfs_commit_metadata(inode);
1225         return ext4_write_inode(inode, &wbc);
1226 }
1227
1228 /*
1229  * Try to release metadata pages (indirect blocks, directories) which are
1230  * mapped via the block device.  Since these pages could have journal heads
1231  * which would prevent try_to_free_buffers() from freeing them, we must use
1232  * jbd2 layer's try_to_free_buffers() function to release them.
1233  */
1234 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1235                                  gfp_t wait)
1236 {
1237         journal_t *journal = EXT4_SB(sb)->s_journal;
1238
1239         WARN_ON(PageChecked(page));
1240         if (!page_has_buffers(page))
1241                 return 0;
1242         if (journal)
1243                 return jbd2_journal_try_to_free_buffers(journal, page,
1244                                                 wait & ~__GFP_DIRECT_RECLAIM);
1245         return try_to_free_buffers(page);
1246 }
1247
1248 #ifdef CONFIG_FS_ENCRYPTION
1249 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1250 {
1251         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1252                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1253 }
1254
1255 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1256                                                         void *fs_data)
1257 {
1258         handle_t *handle = fs_data;
1259         int res, res2, credits, retries = 0;
1260
1261         /*
1262          * Encrypting the root directory is not allowed because e2fsck expects
1263          * lost+found to exist and be unencrypted, and encrypting the root
1264          * directory would imply encrypting the lost+found directory as well as
1265          * the filename "lost+found" itself.
1266          */
1267         if (inode->i_ino == EXT4_ROOT_INO)
1268                 return -EPERM;
1269
1270         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1271                 return -EINVAL;
1272
1273         res = ext4_convert_inline_data(inode);
1274         if (res)
1275                 return res;
1276
1277         /*
1278          * If a journal handle was specified, then the encryption context is
1279          * being set on a new inode via inheritance and is part of a larger
1280          * transaction to create the inode.  Otherwise the encryption context is
1281          * being set on an existing inode in its own transaction.  Only in the
1282          * latter case should the "retry on ENOSPC" logic be used.
1283          */
1284
1285         if (handle) {
1286                 res = ext4_xattr_set_handle(handle, inode,
1287                                             EXT4_XATTR_INDEX_ENCRYPTION,
1288                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1289                                             ctx, len, 0);
1290                 if (!res) {
1291                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1292                         ext4_clear_inode_state(inode,
1293                                         EXT4_STATE_MAY_INLINE_DATA);
1294                         /*
1295                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1296                          * S_DAX may be disabled
1297                          */
1298                         ext4_set_inode_flags(inode);
1299                 }
1300                 return res;
1301         }
1302
1303         res = dquot_initialize(inode);
1304         if (res)
1305                 return res;
1306 retry:
1307         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1308                                      &credits);
1309         if (res)
1310                 return res;
1311
1312         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1313         if (IS_ERR(handle))
1314                 return PTR_ERR(handle);
1315
1316         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1317                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1318                                     ctx, len, 0);
1319         if (!res) {
1320                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1321                 /*
1322                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1323                  * S_DAX may be disabled
1324                  */
1325                 ext4_set_inode_flags(inode);
1326                 res = ext4_mark_inode_dirty(handle, inode);
1327                 if (res)
1328                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1329         }
1330         res2 = ext4_journal_stop(handle);
1331
1332         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1333                 goto retry;
1334         if (!res)
1335                 res = res2;
1336         return res;
1337 }
1338
1339 static bool ext4_dummy_context(struct inode *inode)
1340 {
1341         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1342 }
1343
1344 static const struct fscrypt_operations ext4_cryptops = {
1345         .key_prefix             = "ext4:",
1346         .get_context            = ext4_get_context,
1347         .set_context            = ext4_set_context,
1348         .dummy_context          = ext4_dummy_context,
1349         .empty_dir              = ext4_empty_dir,
1350         .max_namelen            = EXT4_NAME_LEN,
1351 };
1352 #endif
1353
1354 #ifdef CONFIG_QUOTA
1355 static const char * const quotatypes[] = INITQFNAMES;
1356 #define QTYPE2NAME(t) (quotatypes[t])
1357
1358 static int ext4_write_dquot(struct dquot *dquot);
1359 static int ext4_acquire_dquot(struct dquot *dquot);
1360 static int ext4_release_dquot(struct dquot *dquot);
1361 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1362 static int ext4_write_info(struct super_block *sb, int type);
1363 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1364                          const struct path *path);
1365 static int ext4_quota_on_mount(struct super_block *sb, int type);
1366 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1367                                size_t len, loff_t off);
1368 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1369                                 const char *data, size_t len, loff_t off);
1370 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1371                              unsigned int flags);
1372 static int ext4_enable_quotas(struct super_block *sb);
1373 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid);
1374
1375 static struct dquot **ext4_get_dquots(struct inode *inode)
1376 {
1377         return EXT4_I(inode)->i_dquot;
1378 }
1379
1380 static const struct dquot_operations ext4_quota_operations = {
1381         .get_reserved_space     = ext4_get_reserved_space,
1382         .write_dquot            = ext4_write_dquot,
1383         .acquire_dquot          = ext4_acquire_dquot,
1384         .release_dquot          = ext4_release_dquot,
1385         .mark_dirty             = ext4_mark_dquot_dirty,
1386         .write_info             = ext4_write_info,
1387         .alloc_dquot            = dquot_alloc,
1388         .destroy_dquot          = dquot_destroy,
1389         .get_projid             = ext4_get_projid,
1390         .get_inode_usage        = ext4_get_inode_usage,
1391         .get_next_id            = ext4_get_next_id,
1392 };
1393
1394 static const struct quotactl_ops ext4_qctl_operations = {
1395         .quota_on       = ext4_quota_on,
1396         .quota_off      = ext4_quota_off,
1397         .quota_sync     = dquot_quota_sync,
1398         .get_state      = dquot_get_state,
1399         .set_info       = dquot_set_dqinfo,
1400         .get_dqblk      = dquot_get_dqblk,
1401         .set_dqblk      = dquot_set_dqblk,
1402         .get_nextdqblk  = dquot_get_next_dqblk,
1403 };
1404 #endif
1405
1406 static const struct super_operations ext4_sops = {
1407         .alloc_inode    = ext4_alloc_inode,
1408         .free_inode     = ext4_free_in_core_inode,
1409         .destroy_inode  = ext4_destroy_inode,
1410         .write_inode    = ext4_write_inode,
1411         .dirty_inode    = ext4_dirty_inode,
1412         .drop_inode     = ext4_drop_inode,
1413         .evict_inode    = ext4_evict_inode,
1414         .put_super      = ext4_put_super,
1415         .sync_fs        = ext4_sync_fs,
1416         .freeze_fs      = ext4_freeze,
1417         .unfreeze_fs    = ext4_unfreeze,
1418         .statfs         = ext4_statfs,
1419         .remount_fs     = ext4_remount,
1420         .show_options   = ext4_show_options,
1421 #ifdef CONFIG_QUOTA
1422         .quota_read     = ext4_quota_read,
1423         .quota_write    = ext4_quota_write,
1424         .get_dquots     = ext4_get_dquots,
1425 #endif
1426         .bdev_try_to_free_page = bdev_try_to_free_page,
1427 };
1428
1429 static const struct export_operations ext4_export_ops = {
1430         .fh_to_dentry = ext4_fh_to_dentry,
1431         .fh_to_parent = ext4_fh_to_parent,
1432         .get_parent = ext4_get_parent,
1433         .commit_metadata = ext4_nfs_commit_metadata,
1434 };
1435
1436 enum {
1437         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1438         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1439         Opt_nouid32, Opt_debug, Opt_removed,
1440         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1441         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1442         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1443         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1444         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1445         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1446         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1447         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1448         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1449         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1450         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1451         Opt_nowarn_on_error, Opt_mblk_io_submit,
1452         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1453         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1454         Opt_inode_readahead_blks, Opt_journal_ioprio,
1455         Opt_dioread_nolock, Opt_dioread_lock,
1456         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1457         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1458 };
1459
1460 static const match_table_t tokens = {
1461         {Opt_bsd_df, "bsddf"},
1462         {Opt_minix_df, "minixdf"},
1463         {Opt_grpid, "grpid"},
1464         {Opt_grpid, "bsdgroups"},
1465         {Opt_nogrpid, "nogrpid"},
1466         {Opt_nogrpid, "sysvgroups"},
1467         {Opt_resgid, "resgid=%u"},
1468         {Opt_resuid, "resuid=%u"},
1469         {Opt_sb, "sb=%u"},
1470         {Opt_err_cont, "errors=continue"},
1471         {Opt_err_panic, "errors=panic"},
1472         {Opt_err_ro, "errors=remount-ro"},
1473         {Opt_nouid32, "nouid32"},
1474         {Opt_debug, "debug"},
1475         {Opt_removed, "oldalloc"},
1476         {Opt_removed, "orlov"},
1477         {Opt_user_xattr, "user_xattr"},
1478         {Opt_nouser_xattr, "nouser_xattr"},
1479         {Opt_acl, "acl"},
1480         {Opt_noacl, "noacl"},
1481         {Opt_noload, "norecovery"},
1482         {Opt_noload, "noload"},
1483         {Opt_removed, "nobh"},
1484         {Opt_removed, "bh"},
1485         {Opt_commit, "commit=%u"},
1486         {Opt_min_batch_time, "min_batch_time=%u"},
1487         {Opt_max_batch_time, "max_batch_time=%u"},
1488         {Opt_journal_dev, "journal_dev=%u"},
1489         {Opt_journal_path, "journal_path=%s"},
1490         {Opt_journal_checksum, "journal_checksum"},
1491         {Opt_nojournal_checksum, "nojournal_checksum"},
1492         {Opt_journal_async_commit, "journal_async_commit"},
1493         {Opt_abort, "abort"},
1494         {Opt_data_journal, "data=journal"},
1495         {Opt_data_ordered, "data=ordered"},
1496         {Opt_data_writeback, "data=writeback"},
1497         {Opt_data_err_abort, "data_err=abort"},
1498         {Opt_data_err_ignore, "data_err=ignore"},
1499         {Opt_offusrjquota, "usrjquota="},
1500         {Opt_usrjquota, "usrjquota=%s"},
1501         {Opt_offgrpjquota, "grpjquota="},
1502         {Opt_grpjquota, "grpjquota=%s"},
1503         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1504         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1505         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1506         {Opt_grpquota, "grpquota"},
1507         {Opt_noquota, "noquota"},
1508         {Opt_quota, "quota"},
1509         {Opt_usrquota, "usrquota"},
1510         {Opt_prjquota, "prjquota"},
1511         {Opt_barrier, "barrier=%u"},
1512         {Opt_barrier, "barrier"},
1513         {Opt_nobarrier, "nobarrier"},
1514         {Opt_i_version, "i_version"},
1515         {Opt_dax, "dax"},
1516         {Opt_stripe, "stripe=%u"},
1517         {Opt_delalloc, "delalloc"},
1518         {Opt_warn_on_error, "warn_on_error"},
1519         {Opt_nowarn_on_error, "nowarn_on_error"},
1520         {Opt_lazytime, "lazytime"},
1521         {Opt_nolazytime, "nolazytime"},
1522         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1523         {Opt_nodelalloc, "nodelalloc"},
1524         {Opt_removed, "mblk_io_submit"},
1525         {Opt_removed, "nomblk_io_submit"},
1526         {Opt_block_validity, "block_validity"},
1527         {Opt_noblock_validity, "noblock_validity"},
1528         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1529         {Opt_journal_ioprio, "journal_ioprio=%u"},
1530         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1531         {Opt_auto_da_alloc, "auto_da_alloc"},
1532         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1533         {Opt_dioread_nolock, "dioread_nolock"},
1534         {Opt_dioread_lock, "dioread_lock"},
1535         {Opt_discard, "discard"},
1536         {Opt_nodiscard, "nodiscard"},
1537         {Opt_init_itable, "init_itable=%u"},
1538         {Opt_init_itable, "init_itable"},
1539         {Opt_noinit_itable, "noinit_itable"},
1540         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1541         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1542         {Opt_nombcache, "nombcache"},
1543         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1544         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1545         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1546         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1547         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1548         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1549         {Opt_err, NULL},
1550 };
1551
1552 static ext4_fsblk_t get_sb_block(void **data)
1553 {
1554         ext4_fsblk_t    sb_block;
1555         char            *options = (char *) *data;
1556
1557         if (!options || strncmp(options, "sb=", 3) != 0)
1558                 return 1;       /* Default location */
1559
1560         options += 3;
1561         /* TODO: use simple_strtoll with >32bit ext4 */
1562         sb_block = simple_strtoul(options, &options, 0);
1563         if (*options && *options != ',') {
1564                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1565                        (char *) *data);
1566                 return 1;
1567         }
1568         if (*options == ',')
1569                 options++;
1570         *data = (void *) options;
1571
1572         return sb_block;
1573 }
1574
1575 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1576 static const char deprecated_msg[] =
1577         "Mount option \"%s\" will be removed by %s\n"
1578         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1579
1580 #ifdef CONFIG_QUOTA
1581 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1582 {
1583         struct ext4_sb_info *sbi = EXT4_SB(sb);
1584         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1585         int ret = -1;
1586
1587         if (sb_any_quota_loaded(sb) && !old_qname) {
1588                 ext4_msg(sb, KERN_ERR,
1589                         "Cannot change journaled "
1590                         "quota options when quota turned on");
1591                 return -1;
1592         }
1593         if (ext4_has_feature_quota(sb)) {
1594                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1595                          "ignored when QUOTA feature is enabled");
1596                 return 1;
1597         }
1598         qname = match_strdup(args);
1599         if (!qname) {
1600                 ext4_msg(sb, KERN_ERR,
1601                         "Not enough memory for storing quotafile name");
1602                 return -1;
1603         }
1604         if (old_qname) {
1605                 if (strcmp(old_qname, qname) == 0)
1606                         ret = 1;
1607                 else
1608                         ext4_msg(sb, KERN_ERR,
1609                                  "%s quota file already specified",
1610                                  QTYPE2NAME(qtype));
1611                 goto errout;
1612         }
1613         if (strchr(qname, '/')) {
1614                 ext4_msg(sb, KERN_ERR,
1615                         "quotafile must be on filesystem root");
1616                 goto errout;
1617         }
1618         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1619         set_opt(sb, QUOTA);
1620         return 1;
1621 errout:
1622         kfree(qname);
1623         return ret;
1624 }
1625
1626 static int clear_qf_name(struct super_block *sb, int qtype)
1627 {
1628
1629         struct ext4_sb_info *sbi = EXT4_SB(sb);
1630         char *old_qname = get_qf_name(sb, sbi, qtype);
1631
1632         if (sb_any_quota_loaded(sb) && old_qname) {
1633                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1634                         " when quota turned on");
1635                 return -1;
1636         }
1637         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1638         synchronize_rcu();
1639         kfree(old_qname);
1640         return 1;
1641 }
1642 #endif
1643
1644 #define MOPT_SET        0x0001
1645 #define MOPT_CLEAR      0x0002
1646 #define MOPT_NOSUPPORT  0x0004
1647 #define MOPT_EXPLICIT   0x0008
1648 #define MOPT_CLEAR_ERR  0x0010
1649 #define MOPT_GTE0       0x0020
1650 #ifdef CONFIG_QUOTA
1651 #define MOPT_Q          0
1652 #define MOPT_QFMT       0x0040
1653 #else
1654 #define MOPT_Q          MOPT_NOSUPPORT
1655 #define MOPT_QFMT       MOPT_NOSUPPORT
1656 #endif
1657 #define MOPT_DATAJ      0x0080
1658 #define MOPT_NO_EXT2    0x0100
1659 #define MOPT_NO_EXT3    0x0200
1660 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1661 #define MOPT_STRING     0x0400
1662
1663 static const struct mount_opts {
1664         int     token;
1665         int     mount_opt;
1666         int     flags;
1667 } ext4_mount_opts[] = {
1668         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1669         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1670         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1671         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1672         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1673         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1674         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1675          MOPT_EXT4_ONLY | MOPT_SET},
1676         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1677          MOPT_EXT4_ONLY | MOPT_CLEAR},
1678         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1679         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1680         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1681          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1682         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1683          MOPT_EXT4_ONLY | MOPT_CLEAR},
1684         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1685         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1686         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1687          MOPT_EXT4_ONLY | MOPT_CLEAR},
1688         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1689          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1690         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1691                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1692          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1693         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1694         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1695         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1696         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1697         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1698          MOPT_NO_EXT2},
1699         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1700          MOPT_NO_EXT2},
1701         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1702         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1703         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1704         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1705         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1706         {Opt_commit, 0, MOPT_GTE0},
1707         {Opt_max_batch_time, 0, MOPT_GTE0},
1708         {Opt_min_batch_time, 0, MOPT_GTE0},
1709         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1710         {Opt_init_itable, 0, MOPT_GTE0},
1711         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1712         {Opt_stripe, 0, MOPT_GTE0},
1713         {Opt_resuid, 0, MOPT_GTE0},
1714         {Opt_resgid, 0, MOPT_GTE0},
1715         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1716         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1717         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1718         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1719         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1720         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1721          MOPT_NO_EXT2 | MOPT_DATAJ},
1722         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1723         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1724 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1725         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1726         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1727 #else
1728         {Opt_acl, 0, MOPT_NOSUPPORT},
1729         {Opt_noacl, 0, MOPT_NOSUPPORT},
1730 #endif
1731         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1732         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1733         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1734         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1735         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1736                                                         MOPT_SET | MOPT_Q},
1737         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1738                                                         MOPT_SET | MOPT_Q},
1739         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1740                                                         MOPT_SET | MOPT_Q},
1741         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1742                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1743                                                         MOPT_CLEAR | MOPT_Q},
1744         {Opt_usrjquota, 0, MOPT_Q},
1745         {Opt_grpjquota, 0, MOPT_Q},
1746         {Opt_offusrjquota, 0, MOPT_Q},
1747         {Opt_offgrpjquota, 0, MOPT_Q},
1748         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1749         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1750         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1751         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1752         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1753         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1754         {Opt_err, 0, 0}
1755 };
1756
1757 #ifdef CONFIG_UNICODE
1758 static const struct ext4_sb_encodings {
1759         __u16 magic;
1760         char *name;
1761         char *version;
1762 } ext4_sb_encoding_map[] = {
1763         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
1764 };
1765
1766 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
1767                                  const struct ext4_sb_encodings **encoding,
1768                                  __u16 *flags)
1769 {
1770         __u16 magic = le16_to_cpu(es->s_encoding);
1771         int i;
1772
1773         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1774                 if (magic == ext4_sb_encoding_map[i].magic)
1775                         break;
1776
1777         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
1778                 return -EINVAL;
1779
1780         *encoding = &ext4_sb_encoding_map[i];
1781         *flags = le16_to_cpu(es->s_encoding_flags);
1782
1783         return 0;
1784 }
1785 #endif
1786
1787 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1788                             substring_t *args, unsigned long *journal_devnum,
1789                             unsigned int *journal_ioprio, int is_remount)
1790 {
1791         struct ext4_sb_info *sbi = EXT4_SB(sb);
1792         const struct mount_opts *m;
1793         kuid_t uid;
1794         kgid_t gid;
1795         int arg = 0;
1796
1797 #ifdef CONFIG_QUOTA
1798         if (token == Opt_usrjquota)
1799                 return set_qf_name(sb, USRQUOTA, &args[0]);
1800         else if (token == Opt_grpjquota)
1801                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1802         else if (token == Opt_offusrjquota)
1803                 return clear_qf_name(sb, USRQUOTA);
1804         else if (token == Opt_offgrpjquota)
1805                 return clear_qf_name(sb, GRPQUOTA);
1806 #endif
1807         switch (token) {
1808         case Opt_noacl:
1809         case Opt_nouser_xattr:
1810                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1811                 break;
1812         case Opt_sb:
1813                 return 1;       /* handled by get_sb_block() */
1814         case Opt_removed:
1815                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1816                 return 1;
1817         case Opt_abort:
1818                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1819                 return 1;
1820         case Opt_i_version:
1821                 sb->s_flags |= SB_I_VERSION;
1822                 return 1;
1823         case Opt_lazytime:
1824                 sb->s_flags |= SB_LAZYTIME;
1825                 return 1;
1826         case Opt_nolazytime:
1827                 sb->s_flags &= ~SB_LAZYTIME;
1828                 return 1;
1829         }
1830
1831         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1832                 if (token == m->token)
1833                         break;
1834
1835         if (m->token == Opt_err) {
1836                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1837                          "or missing value", opt);
1838                 return -1;
1839         }
1840
1841         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1842                 ext4_msg(sb, KERN_ERR,
1843                          "Mount option \"%s\" incompatible with ext2", opt);
1844                 return -1;
1845         }
1846         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1847                 ext4_msg(sb, KERN_ERR,
1848                          "Mount option \"%s\" incompatible with ext3", opt);
1849                 return -1;
1850         }
1851
1852         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1853                 return -1;
1854         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1855                 return -1;
1856         if (m->flags & MOPT_EXPLICIT) {
1857                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1858                         set_opt2(sb, EXPLICIT_DELALLOC);
1859                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1860                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1861                 } else
1862                         return -1;
1863         }
1864         if (m->flags & MOPT_CLEAR_ERR)
1865                 clear_opt(sb, ERRORS_MASK);
1866         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1867                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1868                          "options when quota turned on");
1869                 return -1;
1870         }
1871
1872         if (m->flags & MOPT_NOSUPPORT) {
1873                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1874         } else if (token == Opt_commit) {
1875                 if (arg == 0)
1876                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1877                 sbi->s_commit_interval = HZ * arg;
1878         } else if (token == Opt_debug_want_extra_isize) {
1879                 sbi->s_want_extra_isize = arg;
1880         } else if (token == Opt_max_batch_time) {
1881                 sbi->s_max_batch_time = arg;
1882         } else if (token == Opt_min_batch_time) {
1883                 sbi->s_min_batch_time = arg;
1884         } else if (token == Opt_inode_readahead_blks) {
1885                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1886                         ext4_msg(sb, KERN_ERR,
1887                                  "EXT4-fs: inode_readahead_blks must be "
1888                                  "0 or a power of 2 smaller than 2^31");
1889                         return -1;
1890                 }
1891                 sbi->s_inode_readahead_blks = arg;
1892         } else if (token == Opt_init_itable) {
1893                 set_opt(sb, INIT_INODE_TABLE);
1894                 if (!args->from)
1895                         arg = EXT4_DEF_LI_WAIT_MULT;
1896                 sbi->s_li_wait_mult = arg;
1897         } else if (token == Opt_max_dir_size_kb) {
1898                 sbi->s_max_dir_size_kb = arg;
1899         } else if (token == Opt_stripe) {
1900                 sbi->s_stripe = arg;
1901         } else if (token == Opt_resuid) {
1902                 uid = make_kuid(current_user_ns(), arg);
1903                 if (!uid_valid(uid)) {
1904                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1905                         return -1;
1906                 }
1907                 sbi->s_resuid = uid;
1908         } else if (token == Opt_resgid) {
1909                 gid = make_kgid(current_user_ns(), arg);
1910                 if (!gid_valid(gid)) {
1911                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1912                         return -1;
1913                 }
1914                 sbi->s_resgid = gid;
1915         } else if (token == Opt_journal_dev) {
1916                 if (is_remount) {
1917                         ext4_msg(sb, KERN_ERR,
1918                                  "Cannot specify journal on remount");
1919                         return -1;
1920                 }
1921                 *journal_devnum = arg;
1922         } else if (token == Opt_journal_path) {
1923                 char *journal_path;
1924                 struct inode *journal_inode;
1925                 struct path path;
1926                 int error;
1927
1928                 if (is_remount) {
1929                         ext4_msg(sb, KERN_ERR,
1930                                  "Cannot specify journal on remount");
1931                         return -1;
1932                 }
1933                 journal_path = match_strdup(&args[0]);
1934                 if (!journal_path) {
1935                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1936                                 "journal device string");
1937                         return -1;
1938                 }
1939
1940                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1941                 if (error) {
1942                         ext4_msg(sb, KERN_ERR, "error: could not find "
1943                                 "journal device path: error %d", error);
1944                         kfree(journal_path);
1945                         return -1;
1946                 }
1947
1948                 journal_inode = d_inode(path.dentry);
1949                 if (!S_ISBLK(journal_inode->i_mode)) {
1950                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1951                                 "is not a block device", journal_path);
1952                         path_put(&path);
1953                         kfree(journal_path);
1954                         return -1;
1955                 }
1956
1957                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1958                 path_put(&path);
1959                 kfree(journal_path);
1960         } else if (token == Opt_journal_ioprio) {
1961                 if (arg > 7) {
1962                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1963                                  " (must be 0-7)");
1964                         return -1;
1965                 }
1966                 *journal_ioprio =
1967                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1968         } else if (token == Opt_test_dummy_encryption) {
1969 #ifdef CONFIG_FS_ENCRYPTION
1970                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1971                 ext4_msg(sb, KERN_WARNING,
1972                          "Test dummy encryption mode enabled");
1973 #else
1974                 ext4_msg(sb, KERN_WARNING,
1975                          "Test dummy encryption mount option ignored");
1976 #endif
1977         } else if (m->flags & MOPT_DATAJ) {
1978                 if (is_remount) {
1979                         if (!sbi->s_journal)
1980                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1981                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1982                                 ext4_msg(sb, KERN_ERR,
1983                                          "Cannot change data mode on remount");
1984                                 return -1;
1985                         }
1986                 } else {
1987                         clear_opt(sb, DATA_FLAGS);
1988                         sbi->s_mount_opt |= m->mount_opt;
1989                 }
1990 #ifdef CONFIG_QUOTA
1991         } else if (m->flags & MOPT_QFMT) {
1992                 if (sb_any_quota_loaded(sb) &&
1993                     sbi->s_jquota_fmt != m->mount_opt) {
1994                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1995                                  "quota options when quota turned on");
1996                         return -1;
1997                 }
1998                 if (ext4_has_feature_quota(sb)) {
1999                         ext4_msg(sb, KERN_INFO,
2000                                  "Quota format mount options ignored "
2001                                  "when QUOTA feature is enabled");
2002                         return 1;
2003                 }
2004                 sbi->s_jquota_fmt = m->mount_opt;
2005 #endif
2006         } else if (token == Opt_dax) {
2007 #ifdef CONFIG_FS_DAX
2008                 ext4_msg(sb, KERN_WARNING,
2009                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2010                 sbi->s_mount_opt |= m->mount_opt;
2011 #else
2012                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2013                 return -1;
2014 #endif
2015         } else if (token == Opt_data_err_abort) {
2016                 sbi->s_mount_opt |= m->mount_opt;
2017         } else if (token == Opt_data_err_ignore) {
2018                 sbi->s_mount_opt &= ~m->mount_opt;
2019         } else {
2020                 if (!args->from)
2021                         arg = 1;
2022                 if (m->flags & MOPT_CLEAR)
2023                         arg = !arg;
2024                 else if (unlikely(!(m->flags & MOPT_SET))) {
2025                         ext4_msg(sb, KERN_WARNING,
2026                                  "buggy handling of option %s", opt);
2027                         WARN_ON(1);
2028                         return -1;
2029                 }
2030                 if (arg != 0)
2031                         sbi->s_mount_opt |= m->mount_opt;
2032                 else
2033                         sbi->s_mount_opt &= ~m->mount_opt;
2034         }
2035         return 1;
2036 }
2037
2038 static int parse_options(char *options, struct super_block *sb,
2039                          unsigned long *journal_devnum,
2040                          unsigned int *journal_ioprio,
2041                          int is_remount)
2042 {
2043         struct ext4_sb_info *sbi = EXT4_SB(sb);
2044         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2045         substring_t args[MAX_OPT_ARGS];
2046         int token;
2047
2048         if (!options)
2049                 return 1;
2050
2051         while ((p = strsep(&options, ",")) != NULL) {
2052                 if (!*p)
2053                         continue;
2054                 /*
2055                  * Initialize args struct so we know whether arg was
2056                  * found; some options take optional arguments.
2057                  */
2058                 args[0].to = args[0].from = NULL;
2059                 token = match_token(p, tokens, args);
2060                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2061                                      journal_ioprio, is_remount) < 0)
2062                         return 0;
2063         }
2064 #ifdef CONFIG_QUOTA
2065         /*
2066          * We do the test below only for project quotas. 'usrquota' and
2067          * 'grpquota' mount options are allowed even without quota feature
2068          * to support legacy quotas in quota files.
2069          */
2070         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2071                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2072                          "Cannot enable project quota enforcement.");
2073                 return 0;
2074         }
2075         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2076         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2077         if (usr_qf_name || grp_qf_name) {
2078                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2079                         clear_opt(sb, USRQUOTA);
2080
2081                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2082                         clear_opt(sb, GRPQUOTA);
2083
2084                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2085                         ext4_msg(sb, KERN_ERR, "old and new quota "
2086                                         "format mixing");
2087                         return 0;
2088                 }
2089
2090                 if (!sbi->s_jquota_fmt) {
2091                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2092                                         "not specified");
2093                         return 0;
2094                 }
2095         }
2096 #endif
2097         if (test_opt(sb, DIOREAD_NOLOCK)) {
2098                 int blocksize =
2099                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2100
2101                 if (blocksize < PAGE_SIZE) {
2102                         ext4_msg(sb, KERN_ERR, "can't mount with "
2103                                  "dioread_nolock if block size != PAGE_SIZE");
2104                         return 0;
2105                 }
2106         }
2107         return 1;
2108 }
2109
2110 static inline void ext4_show_quota_options(struct seq_file *seq,
2111                                            struct super_block *sb)
2112 {
2113 #if defined(CONFIG_QUOTA)
2114         struct ext4_sb_info *sbi = EXT4_SB(sb);
2115         char *usr_qf_name, *grp_qf_name;
2116
2117         if (sbi->s_jquota_fmt) {
2118                 char *fmtname = "";
2119
2120                 switch (sbi->s_jquota_fmt) {
2121                 case QFMT_VFS_OLD:
2122                         fmtname = "vfsold";
2123                         break;
2124                 case QFMT_VFS_V0:
2125                         fmtname = "vfsv0";
2126                         break;
2127                 case QFMT_VFS_V1:
2128                         fmtname = "vfsv1";
2129                         break;
2130                 }
2131                 seq_printf(seq, ",jqfmt=%s", fmtname);
2132         }
2133
2134         rcu_read_lock();
2135         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2136         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2137         if (usr_qf_name)
2138                 seq_show_option(seq, "usrjquota", usr_qf_name);
2139         if (grp_qf_name)
2140                 seq_show_option(seq, "grpjquota", grp_qf_name);
2141         rcu_read_unlock();
2142 #endif
2143 }
2144
2145 static const char *token2str(int token)
2146 {
2147         const struct match_token *t;
2148
2149         for (t = tokens; t->token != Opt_err; t++)
2150                 if (t->token == token && !strchr(t->pattern, '='))
2151                         break;
2152         return t->pattern;
2153 }
2154
2155 /*
2156  * Show an option if
2157  *  - it's set to a non-default value OR
2158  *  - if the per-sb default is different from the global default
2159  */
2160 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2161                               int nodefs)
2162 {
2163         struct ext4_sb_info *sbi = EXT4_SB(sb);
2164         struct ext4_super_block *es = sbi->s_es;
2165         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2166         const struct mount_opts *m;
2167         char sep = nodefs ? '\n' : ',';
2168
2169 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2170 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2171
2172         if (sbi->s_sb_block != 1)
2173                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2174
2175         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2176                 int want_set = m->flags & MOPT_SET;
2177                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2178                     (m->flags & MOPT_CLEAR_ERR))
2179                         continue;
2180                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2181                         continue; /* skip if same as the default */
2182                 if ((want_set &&
2183                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2184                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2185                         continue; /* select Opt_noFoo vs Opt_Foo */
2186                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2187         }
2188
2189         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2190             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2191                 SEQ_OPTS_PRINT("resuid=%u",
2192                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2193         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2194             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2195                 SEQ_OPTS_PRINT("resgid=%u",
2196                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2197         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2198         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2199                 SEQ_OPTS_PUTS("errors=remount-ro");
2200         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2201                 SEQ_OPTS_PUTS("errors=continue");
2202         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2203                 SEQ_OPTS_PUTS("errors=panic");
2204         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2205                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2206         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2207                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2208         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2209                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2210         if (sb->s_flags & SB_I_VERSION)
2211                 SEQ_OPTS_PUTS("i_version");
2212         if (nodefs || sbi->s_stripe)
2213                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2214         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2215                         (sbi->s_mount_opt ^ def_mount_opt)) {
2216                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2217                         SEQ_OPTS_PUTS("data=journal");
2218                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2219                         SEQ_OPTS_PUTS("data=ordered");
2220                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2221                         SEQ_OPTS_PUTS("data=writeback");
2222         }
2223         if (nodefs ||
2224             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2225                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2226                                sbi->s_inode_readahead_blks);
2227
2228         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2229                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2230                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2231         if (nodefs || sbi->s_max_dir_size_kb)
2232                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2233         if (test_opt(sb, DATA_ERR_ABORT))
2234                 SEQ_OPTS_PUTS("data_err=abort");
2235         if (DUMMY_ENCRYPTION_ENABLED(sbi))
2236                 SEQ_OPTS_PUTS("test_dummy_encryption");
2237
2238         ext4_show_quota_options(seq, sb);
2239         return 0;
2240 }
2241
2242 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2243 {
2244         return _ext4_show_options(seq, root->d_sb, 0);
2245 }
2246
2247 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2248 {
2249         struct super_block *sb = seq->private;
2250         int rc;
2251
2252         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2253         rc = _ext4_show_options(seq, sb, 1);
2254         seq_puts(seq, "\n");
2255         return rc;
2256 }
2257
2258 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2259                             int read_only)
2260 {
2261         struct ext4_sb_info *sbi = EXT4_SB(sb);
2262         int err = 0;
2263
2264         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2265                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2266                          "forcing read-only mode");
2267                 err = -EROFS;
2268         }
2269         if (read_only)
2270                 goto done;
2271         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2272                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2273                          "running e2fsck is recommended");
2274         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2275                 ext4_msg(sb, KERN_WARNING,
2276                          "warning: mounting fs with errors, "
2277                          "running e2fsck is recommended");
2278         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2279                  le16_to_cpu(es->s_mnt_count) >=
2280                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2281                 ext4_msg(sb, KERN_WARNING,
2282                          "warning: maximal mount count reached, "
2283                          "running e2fsck is recommended");
2284         else if (le32_to_cpu(es->s_checkinterval) &&
2285                  (ext4_get_tstamp(es, s_lastcheck) +
2286                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2287                 ext4_msg(sb, KERN_WARNING,
2288                          "warning: checktime reached, "
2289                          "running e2fsck is recommended");
2290         if (!sbi->s_journal)
2291                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2292         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2293                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2294         le16_add_cpu(&es->s_mnt_count, 1);
2295         ext4_update_tstamp(es, s_mtime);
2296         if (sbi->s_journal)
2297                 ext4_set_feature_journal_needs_recovery(sb);
2298
2299         err = ext4_commit_super(sb, 1);
2300 done:
2301         if (test_opt(sb, DEBUG))
2302                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2303                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2304                         sb->s_blocksize,
2305                         sbi->s_groups_count,
2306                         EXT4_BLOCKS_PER_GROUP(sb),
2307                         EXT4_INODES_PER_GROUP(sb),
2308                         sbi->s_mount_opt, sbi->s_mount_opt2);
2309
2310         cleancache_init_fs(sb);
2311         return err;
2312 }
2313
2314 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2315 {
2316         struct ext4_sb_info *sbi = EXT4_SB(sb);
2317         struct flex_groups *new_groups;
2318         int size;
2319
2320         if (!sbi->s_log_groups_per_flex)
2321                 return 0;
2322
2323         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2324         if (size <= sbi->s_flex_groups_allocated)
2325                 return 0;
2326
2327         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
2328         new_groups = kvzalloc(size, GFP_KERNEL);
2329         if (!new_groups) {
2330                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
2331                          size / (int) sizeof(struct flex_groups));
2332                 return -ENOMEM;
2333         }
2334
2335         if (sbi->s_flex_groups) {
2336                 memcpy(new_groups, sbi->s_flex_groups,
2337                        (sbi->s_flex_groups_allocated *
2338                         sizeof(struct flex_groups)));
2339                 kvfree(sbi->s_flex_groups);
2340         }
2341         sbi->s_flex_groups = new_groups;
2342         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
2343         return 0;
2344 }
2345
2346 static int ext4_fill_flex_info(struct super_block *sb)
2347 {
2348         struct ext4_sb_info *sbi = EXT4_SB(sb);
2349         struct ext4_group_desc *gdp = NULL;
2350         ext4_group_t flex_group;
2351         int i, err;
2352
2353         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2354         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2355                 sbi->s_log_groups_per_flex = 0;
2356                 return 1;
2357         }
2358
2359         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2360         if (err)
2361                 goto failed;
2362
2363         for (i = 0; i < sbi->s_groups_count; i++) {
2364                 gdp = ext4_get_group_desc(sb, i, NULL);
2365
2366                 flex_group = ext4_flex_group(sbi, i);
2367                 atomic_add(ext4_free_inodes_count(sb, gdp),
2368                            &sbi->s_flex_groups[flex_group].free_inodes);
2369                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2370                              &sbi->s_flex_groups[flex_group].free_clusters);
2371                 atomic_add(ext4_used_dirs_count(sb, gdp),
2372                            &sbi->s_flex_groups[flex_group].used_dirs);
2373         }
2374
2375         return 1;
2376 failed:
2377         return 0;
2378 }
2379
2380 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2381                                    struct ext4_group_desc *gdp)
2382 {
2383         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2384         __u16 crc = 0;
2385         __le32 le_group = cpu_to_le32(block_group);
2386         struct ext4_sb_info *sbi = EXT4_SB(sb);
2387
2388         if (ext4_has_metadata_csum(sbi->s_sb)) {
2389                 /* Use new metadata_csum algorithm */
2390                 __u32 csum32;
2391                 __u16 dummy_csum = 0;
2392
2393                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2394                                      sizeof(le_group));
2395                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2396                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2397                                      sizeof(dummy_csum));
2398                 offset += sizeof(dummy_csum);
2399                 if (offset < sbi->s_desc_size)
2400                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2401                                              sbi->s_desc_size - offset);
2402
2403                 crc = csum32 & 0xFFFF;
2404                 goto out;
2405         }
2406
2407         /* old crc16 code */
2408         if (!ext4_has_feature_gdt_csum(sb))
2409                 return 0;
2410
2411         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2412         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2413         crc = crc16(crc, (__u8 *)gdp, offset);
2414         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2415         /* for checksum of struct ext4_group_desc do the rest...*/
2416         if (ext4_has_feature_64bit(sb) &&
2417             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2418                 crc = crc16(crc, (__u8 *)gdp + offset,
2419                             le16_to_cpu(sbi->s_es->s_desc_size) -
2420                                 offset);
2421
2422 out:
2423         return cpu_to_le16(crc);
2424 }
2425
2426 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2427                                 struct ext4_group_desc *gdp)
2428 {
2429         if (ext4_has_group_desc_csum(sb) &&
2430             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2431                 return 0;
2432
2433         return 1;
2434 }
2435
2436 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2437                               struct ext4_group_desc *gdp)
2438 {
2439         if (!ext4_has_group_desc_csum(sb))
2440                 return;
2441         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2442 }
2443
2444 /* Called at mount-time, super-block is locked */
2445 static int ext4_check_descriptors(struct super_block *sb,
2446                                   ext4_fsblk_t sb_block,
2447                                   ext4_group_t *first_not_zeroed)
2448 {
2449         struct ext4_sb_info *sbi = EXT4_SB(sb);
2450         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2451         ext4_fsblk_t last_block;
2452         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2453         ext4_fsblk_t block_bitmap;
2454         ext4_fsblk_t inode_bitmap;
2455         ext4_fsblk_t inode_table;
2456         int flexbg_flag = 0;
2457         ext4_group_t i, grp = sbi->s_groups_count;
2458
2459         if (ext4_has_feature_flex_bg(sb))
2460                 flexbg_flag = 1;
2461
2462         ext4_debug("Checking group descriptors");
2463
2464         for (i = 0; i < sbi->s_groups_count; i++) {
2465                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2466
2467                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2468                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2469                 else
2470                         last_block = first_block +
2471                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2472
2473                 if ((grp == sbi->s_groups_count) &&
2474                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2475                         grp = i;
2476
2477                 block_bitmap = ext4_block_bitmap(sb, gdp);
2478                 if (block_bitmap == sb_block) {
2479                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2480                                  "Block bitmap for group %u overlaps "
2481                                  "superblock", i);
2482                         if (!sb_rdonly(sb))
2483                                 return 0;
2484                 }
2485                 if (block_bitmap >= sb_block + 1 &&
2486                     block_bitmap <= last_bg_block) {
2487                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2488                                  "Block bitmap for group %u overlaps "
2489                                  "block group descriptors", i);
2490                         if (!sb_rdonly(sb))
2491                                 return 0;
2492                 }
2493                 if (block_bitmap < first_block || block_bitmap > last_block) {
2494                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2495                                "Block bitmap for group %u not in group "
2496                                "(block %llu)!", i, block_bitmap);
2497                         return 0;
2498                 }
2499                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2500                 if (inode_bitmap == sb_block) {
2501                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2502                                  "Inode bitmap for group %u overlaps "
2503                                  "superblock", i);
2504                         if (!sb_rdonly(sb))
2505                                 return 0;
2506                 }
2507                 if (inode_bitmap >= sb_block + 1 &&
2508                     inode_bitmap <= last_bg_block) {
2509                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2510                                  "Inode bitmap for group %u overlaps "
2511                                  "block group descriptors", i);
2512                         if (!sb_rdonly(sb))
2513                                 return 0;
2514                 }
2515                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2516                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2517                                "Inode bitmap for group %u not in group "
2518                                "(block %llu)!", i, inode_bitmap);
2519                         return 0;
2520                 }
2521                 inode_table = ext4_inode_table(sb, gdp);
2522                 if (inode_table == sb_block) {
2523                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2524                                  "Inode table for group %u overlaps "
2525                                  "superblock", i);
2526                         if (!sb_rdonly(sb))
2527                                 return 0;
2528                 }
2529                 if (inode_table >= sb_block + 1 &&
2530                     inode_table <= last_bg_block) {
2531                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2532                                  "Inode table for group %u overlaps "
2533                                  "block group descriptors", i);
2534                         if (!sb_rdonly(sb))
2535                                 return 0;
2536                 }
2537                 if (inode_table < first_block ||
2538                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2539                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2540                                "Inode table for group %u not in group "
2541                                "(block %llu)!", i, inode_table);
2542                         return 0;
2543                 }
2544                 ext4_lock_group(sb, i);
2545                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2546                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2547                                  "Checksum for group %u failed (%u!=%u)",
2548                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2549                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2550                         if (!sb_rdonly(sb)) {
2551                                 ext4_unlock_group(sb, i);
2552                                 return 0;
2553                         }
2554                 }
2555                 ext4_unlock_group(sb, i);
2556                 if (!flexbg_flag)
2557                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2558         }
2559         if (NULL != first_not_zeroed)
2560                 *first_not_zeroed = grp;
2561         return 1;
2562 }
2563
2564 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2565  * the superblock) which were deleted from all directories, but held open by
2566  * a process at the time of a crash.  We walk the list and try to delete these
2567  * inodes at recovery time (only with a read-write filesystem).
2568  *
2569  * In order to keep the orphan inode chain consistent during traversal (in
2570  * case of crash during recovery), we link each inode into the superblock
2571  * orphan list_head and handle it the same way as an inode deletion during
2572  * normal operation (which journals the operations for us).
2573  *
2574  * We only do an iget() and an iput() on each inode, which is very safe if we
2575  * accidentally point at an in-use or already deleted inode.  The worst that
2576  * can happen in this case is that we get a "bit already cleared" message from
2577  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2578  * e2fsck was run on this filesystem, and it must have already done the orphan
2579  * inode cleanup for us, so we can safely abort without any further action.
2580  */
2581 static void ext4_orphan_cleanup(struct super_block *sb,
2582                                 struct ext4_super_block *es)
2583 {
2584         unsigned int s_flags = sb->s_flags;
2585         int ret, nr_orphans = 0, nr_truncates = 0;
2586 #ifdef CONFIG_QUOTA
2587         int quota_update = 0;
2588         int i;
2589 #endif
2590         if (!es->s_last_orphan) {
2591                 jbd_debug(4, "no orphan inodes to clean up\n");
2592                 return;
2593         }
2594
2595         if (bdev_read_only(sb->s_bdev)) {
2596                 ext4_msg(sb, KERN_ERR, "write access "
2597                         "unavailable, skipping orphan cleanup");
2598                 return;
2599         }
2600
2601         /* Check if feature set would not allow a r/w mount */
2602         if (!ext4_feature_set_ok(sb, 0)) {
2603                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2604                          "unknown ROCOMPAT features");
2605                 return;
2606         }
2607
2608         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2609                 /* don't clear list on RO mount w/ errors */
2610                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2611                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2612                                   "clearing orphan list.\n");
2613                         es->s_last_orphan = 0;
2614                 }
2615                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2616                 return;
2617         }
2618
2619         if (s_flags & SB_RDONLY) {
2620                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2621                 sb->s_flags &= ~SB_RDONLY;
2622         }
2623 #ifdef CONFIG_QUOTA
2624         /* Needed for iput() to work correctly and not trash data */
2625         sb->s_flags |= SB_ACTIVE;
2626
2627         /*
2628          * Turn on quotas which were not enabled for read-only mounts if
2629          * filesystem has quota feature, so that they are updated correctly.
2630          */
2631         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2632                 int ret = ext4_enable_quotas(sb);
2633
2634                 if (!ret)
2635                         quota_update = 1;
2636                 else
2637                         ext4_msg(sb, KERN_ERR,
2638                                 "Cannot turn on quotas: error %d", ret);
2639         }
2640
2641         /* Turn on journaled quotas used for old sytle */
2642         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2643                 if (EXT4_SB(sb)->s_qf_names[i]) {
2644                         int ret = ext4_quota_on_mount(sb, i);
2645
2646                         if (!ret)
2647                                 quota_update = 1;
2648                         else
2649                                 ext4_msg(sb, KERN_ERR,
2650                                         "Cannot turn on journaled "
2651                                         "quota: type %d: error %d", i, ret);
2652                 }
2653         }
2654 #endif
2655
2656         while (es->s_last_orphan) {
2657                 struct inode *inode;
2658
2659                 /*
2660                  * We may have encountered an error during cleanup; if
2661                  * so, skip the rest.
2662                  */
2663                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2664                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2665                         es->s_last_orphan = 0;
2666                         break;
2667                 }
2668
2669                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2670                 if (IS_ERR(inode)) {
2671                         es->s_last_orphan = 0;
2672                         break;
2673                 }
2674
2675                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2676                 dquot_initialize(inode);
2677                 if (inode->i_nlink) {
2678                         if (test_opt(sb, DEBUG))
2679                                 ext4_msg(sb, KERN_DEBUG,
2680                                         "%s: truncating inode %lu to %lld bytes",
2681                                         __func__, inode->i_ino, inode->i_size);
2682                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2683                                   inode->i_ino, inode->i_size);
2684                         inode_lock(inode);
2685                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2686                         ret = ext4_truncate(inode);
2687                         if (ret)
2688                                 ext4_std_error(inode->i_sb, ret);
2689                         inode_unlock(inode);
2690                         nr_truncates++;
2691                 } else {
2692                         if (test_opt(sb, DEBUG))
2693                                 ext4_msg(sb, KERN_DEBUG,
2694                                         "%s: deleting unreferenced inode %lu",
2695                                         __func__, inode->i_ino);
2696                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2697                                   inode->i_ino);
2698                         nr_orphans++;
2699                 }
2700                 iput(inode);  /* The delete magic happens here! */
2701         }
2702
2703 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2704
2705         if (nr_orphans)
2706                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2707                        PLURAL(nr_orphans));
2708         if (nr_truncates)
2709                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2710                        PLURAL(nr_truncates));
2711 #ifdef CONFIG_QUOTA
2712         /* Turn off quotas if they were enabled for orphan cleanup */
2713         if (quota_update) {
2714                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2715                         if (sb_dqopt(sb)->files[i])
2716                                 dquot_quota_off(sb, i);
2717                 }
2718         }
2719 #endif
2720         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2721 }
2722
2723 /*
2724  * Maximal extent format file size.
2725  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2726  * extent format containers, within a sector_t, and within i_blocks
2727  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2728  * so that won't be a limiting factor.
2729  *
2730  * However there is other limiting factor. We do store extents in the form
2731  * of starting block and length, hence the resulting length of the extent
2732  * covering maximum file size must fit into on-disk format containers as
2733  * well. Given that length is always by 1 unit bigger than max unit (because
2734  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2735  *
2736  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2737  */
2738 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2739 {
2740         loff_t res;
2741         loff_t upper_limit = MAX_LFS_FILESIZE;
2742
2743         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
2744
2745         if (!has_huge_files) {
2746                 upper_limit = (1LL << 32) - 1;
2747
2748                 /* total blocks in file system block size */
2749                 upper_limit >>= (blkbits - 9);
2750                 upper_limit <<= blkbits;
2751         }
2752
2753         /*
2754          * 32-bit extent-start container, ee_block. We lower the maxbytes
2755          * by one fs block, so ee_len can cover the extent of maximum file
2756          * size
2757          */
2758         res = (1LL << 32) - 1;
2759         res <<= blkbits;
2760
2761         /* Sanity check against vm- & vfs- imposed limits */
2762         if (res > upper_limit)
2763                 res = upper_limit;
2764
2765         return res;
2766 }
2767
2768 /*
2769  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2770  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2771  * We need to be 1 filesystem block less than the 2^48 sector limit.
2772  */
2773 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2774 {
2775         loff_t res = EXT4_NDIR_BLOCKS;
2776         int meta_blocks;
2777         loff_t upper_limit;
2778         /* This is calculated to be the largest file size for a dense, block
2779          * mapped file such that the file's total number of 512-byte sectors,
2780          * including data and all indirect blocks, does not exceed (2^48 - 1).
2781          *
2782          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2783          * number of 512-byte sectors of the file.
2784          */
2785
2786         if (!has_huge_files) {
2787                 /*
2788                  * !has_huge_files or implies that the inode i_block field
2789                  * represents total file blocks in 2^32 512-byte sectors ==
2790                  * size of vfs inode i_blocks * 8
2791                  */
2792                 upper_limit = (1LL << 32) - 1;
2793
2794                 /* total blocks in file system block size */
2795                 upper_limit >>= (bits - 9);
2796
2797         } else {
2798                 /*
2799                  * We use 48 bit ext4_inode i_blocks
2800                  * With EXT4_HUGE_FILE_FL set the i_blocks
2801                  * represent total number of blocks in
2802                  * file system block size
2803                  */
2804                 upper_limit = (1LL << 48) - 1;
2805
2806         }
2807
2808         /* indirect blocks */
2809         meta_blocks = 1;
2810         /* double indirect blocks */
2811         meta_blocks += 1 + (1LL << (bits-2));
2812         /* tripple indirect blocks */
2813         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2814
2815         upper_limit -= meta_blocks;
2816         upper_limit <<= bits;
2817
2818         res += 1LL << (bits-2);
2819         res += 1LL << (2*(bits-2));
2820         res += 1LL << (3*(bits-2));
2821         res <<= bits;
2822         if (res > upper_limit)
2823                 res = upper_limit;
2824
2825         if (res > MAX_LFS_FILESIZE)
2826                 res = MAX_LFS_FILESIZE;
2827
2828         return res;
2829 }
2830
2831 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2832                                    ext4_fsblk_t logical_sb_block, int nr)
2833 {
2834         struct ext4_sb_info *sbi = EXT4_SB(sb);
2835         ext4_group_t bg, first_meta_bg;
2836         int has_super = 0;
2837
2838         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2839
2840         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2841                 return logical_sb_block + nr + 1;
2842         bg = sbi->s_desc_per_block * nr;
2843         if (ext4_bg_has_super(sb, bg))
2844                 has_super = 1;
2845
2846         /*
2847          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2848          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2849          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2850          * compensate.
2851          */
2852         if (sb->s_blocksize == 1024 && nr == 0 &&
2853             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
2854                 has_super++;
2855
2856         return (has_super + ext4_group_first_block_no(sb, bg));
2857 }
2858
2859 /**
2860  * ext4_get_stripe_size: Get the stripe size.
2861  * @sbi: In memory super block info
2862  *
2863  * If we have specified it via mount option, then
2864  * use the mount option value. If the value specified at mount time is
2865  * greater than the blocks per group use the super block value.
2866  * If the super block value is greater than blocks per group return 0.
2867  * Allocator needs it be less than blocks per group.
2868  *
2869  */
2870 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2871 {
2872         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2873         unsigned long stripe_width =
2874                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2875         int ret;
2876
2877         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2878                 ret = sbi->s_stripe;
2879         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2880                 ret = stripe_width;
2881         else if (stride && stride <= sbi->s_blocks_per_group)
2882                 ret = stride;
2883         else
2884                 ret = 0;
2885
2886         /*
2887          * If the stripe width is 1, this makes no sense and
2888          * we set it to 0 to turn off stripe handling code.
2889          */
2890         if (ret <= 1)
2891                 ret = 0;
2892
2893         return ret;
2894 }
2895
2896 /*
2897  * Check whether this filesystem can be mounted based on
2898  * the features present and the RDONLY/RDWR mount requested.
2899  * Returns 1 if this filesystem can be mounted as requested,
2900  * 0 if it cannot be.
2901  */
2902 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2903 {
2904         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2905                 ext4_msg(sb, KERN_ERR,
2906                         "Couldn't mount because of "
2907                         "unsupported optional features (%x)",
2908                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2909                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2910                 return 0;
2911         }
2912
2913 #ifndef CONFIG_UNICODE
2914         if (ext4_has_feature_casefold(sb)) {
2915                 ext4_msg(sb, KERN_ERR,
2916                          "Filesystem with casefold feature cannot be "
2917                          "mounted without CONFIG_UNICODE");
2918                 return 0;
2919         }
2920 #endif
2921
2922         if (readonly)
2923                 return 1;
2924
2925         if (ext4_has_feature_readonly(sb)) {
2926                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2927                 sb->s_flags |= SB_RDONLY;
2928                 return 1;
2929         }
2930
2931         /* Check that feature set is OK for a read-write mount */
2932         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2933                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2934                          "unsupported optional features (%x)",
2935                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2936                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2937                 return 0;
2938         }
2939         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2940                 ext4_msg(sb, KERN_ERR,
2941                          "Can't support bigalloc feature without "
2942                          "extents feature\n");
2943                 return 0;
2944         }
2945
2946 #ifndef CONFIG_QUOTA
2947         if (ext4_has_feature_quota(sb) && !readonly) {
2948                 ext4_msg(sb, KERN_ERR,
2949                          "Filesystem with quota feature cannot be mounted RDWR "
2950                          "without CONFIG_QUOTA");
2951                 return 0;
2952         }
2953         if (ext4_has_feature_project(sb) && !readonly) {
2954                 ext4_msg(sb, KERN_ERR,
2955                          "Filesystem with project quota feature cannot be mounted RDWR "
2956                          "without CONFIG_QUOTA");
2957                 return 0;
2958         }
2959 #endif  /* CONFIG_QUOTA */
2960         return 1;
2961 }
2962
2963 /*
2964  * This function is called once a day if we have errors logged
2965  * on the file system
2966  */
2967 static void print_daily_error_info(struct timer_list *t)
2968 {
2969         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
2970         struct super_block *sb = sbi->s_sb;
2971         struct ext4_super_block *es = sbi->s_es;
2972
2973         if (es->s_error_count)
2974                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2975                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2976                          le32_to_cpu(es->s_error_count));
2977         if (es->s_first_error_time) {
2978                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
2979                        sb->s_id,
2980                        ext4_get_tstamp(es, s_first_error_time),
2981                        (int) sizeof(es->s_first_error_func),
2982                        es->s_first_error_func,
2983                        le32_to_cpu(es->s_first_error_line));
2984                 if (es->s_first_error_ino)
2985                         printk(KERN_CONT ": inode %u",
2986                                le32_to_cpu(es->s_first_error_ino));
2987                 if (es->s_first_error_block)
2988                         printk(KERN_CONT ": block %llu", (unsigned long long)
2989                                le64_to_cpu(es->s_first_error_block));
2990                 printk(KERN_CONT "\n");
2991         }
2992         if (es->s_last_error_time) {
2993                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
2994                        sb->s_id,
2995                        ext4_get_tstamp(es, s_last_error_time),
2996                        (int) sizeof(es->s_last_error_func),
2997                        es->s_last_error_func,
2998                        le32_to_cpu(es->s_last_error_line));
2999                 if (es->s_last_error_ino)
3000                         printk(KERN_CONT ": inode %u",
3001                                le32_to_cpu(es->s_last_error_ino));
3002                 if (es->s_last_error_block)
3003                         printk(KERN_CONT ": block %llu", (unsigned long long)
3004                                le64_to_cpu(es->s_last_error_block));
3005                 printk(KERN_CONT "\n");
3006         }
3007         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3008 }
3009
3010 /* Find next suitable group and run ext4_init_inode_table */
3011 static int ext4_run_li_request(struct ext4_li_request *elr)
3012 {
3013         struct ext4_group_desc *gdp = NULL;
3014         ext4_group_t group, ngroups;
3015         struct super_block *sb;
3016         unsigned long timeout = 0;
3017         int ret = 0;
3018
3019         sb = elr->lr_super;
3020         ngroups = EXT4_SB(sb)->s_groups_count;
3021
3022         for (group = elr->lr_next_group; group < ngroups; group++) {
3023                 gdp = ext4_get_group_desc(sb, group, NULL);
3024                 if (!gdp) {
3025                         ret = 1;
3026                         break;
3027                 }
3028
3029                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3030                         break;
3031         }
3032
3033         if (group >= ngroups)
3034                 ret = 1;
3035
3036         if (!ret) {
3037                 timeout = jiffies;
3038                 ret = ext4_init_inode_table(sb, group,
3039                                             elr->lr_timeout ? 0 : 1);
3040                 if (elr->lr_timeout == 0) {
3041                         timeout = (jiffies - timeout) *
3042                                   elr->lr_sbi->s_li_wait_mult;
3043                         elr->lr_timeout = timeout;
3044                 }
3045                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3046                 elr->lr_next_group = group + 1;
3047         }
3048         return ret;
3049 }
3050
3051 /*
3052  * Remove lr_request from the list_request and free the
3053  * request structure. Should be called with li_list_mtx held
3054  */
3055 static void ext4_remove_li_request(struct ext4_li_request *elr)
3056 {
3057         struct ext4_sb_info *sbi;
3058
3059         if (!elr)
3060                 return;
3061
3062         sbi = elr->lr_sbi;
3063
3064         list_del(&elr->lr_request);
3065         sbi->s_li_request = NULL;
3066         kfree(elr);
3067 }
3068
3069 static void ext4_unregister_li_request(struct super_block *sb)
3070 {
3071         mutex_lock(&ext4_li_mtx);
3072         if (!ext4_li_info) {
3073                 mutex_unlock(&ext4_li_mtx);
3074                 return;
3075         }
3076
3077         mutex_lock(&ext4_li_info->li_list_mtx);
3078         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3079         mutex_unlock(&ext4_li_info->li_list_mtx);
3080         mutex_unlock(&ext4_li_mtx);
3081 }
3082
3083 static struct task_struct *ext4_lazyinit_task;
3084
3085 /*
3086  * This is the function where ext4lazyinit thread lives. It walks
3087  * through the request list searching for next scheduled filesystem.
3088  * When such a fs is found, run the lazy initialization request
3089  * (ext4_rn_li_request) and keep track of the time spend in this
3090  * function. Based on that time we compute next schedule time of
3091  * the request. When walking through the list is complete, compute
3092  * next waking time and put itself into sleep.
3093  */
3094 static int ext4_lazyinit_thread(void *arg)
3095 {
3096         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3097         struct list_head *pos, *n;
3098         struct ext4_li_request *elr;
3099         unsigned long next_wakeup, cur;
3100
3101         BUG_ON(NULL == eli);
3102
3103 cont_thread:
3104         while (true) {
3105                 next_wakeup = MAX_JIFFY_OFFSET;
3106
3107                 mutex_lock(&eli->li_list_mtx);
3108                 if (list_empty(&eli->li_request_list)) {
3109                         mutex_unlock(&eli->li_list_mtx);
3110                         goto exit_thread;
3111                 }
3112                 list_for_each_safe(pos, n, &eli->li_request_list) {
3113                         int err = 0;
3114                         int progress = 0;
3115                         elr = list_entry(pos, struct ext4_li_request,
3116                                          lr_request);
3117
3118                         if (time_before(jiffies, elr->lr_next_sched)) {
3119                                 if (time_before(elr->lr_next_sched, next_wakeup))
3120                                         next_wakeup = elr->lr_next_sched;
3121                                 continue;
3122                         }
3123                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3124                                 if (sb_start_write_trylock(elr->lr_super)) {
3125                                         progress = 1;
3126                                         /*
3127                                          * We hold sb->s_umount, sb can not
3128                                          * be removed from the list, it is
3129                                          * now safe to drop li_list_mtx
3130                                          */
3131                                         mutex_unlock(&eli->li_list_mtx);
3132                                         err = ext4_run_li_request(elr);
3133                                         sb_end_write(elr->lr_super);
3134                                         mutex_lock(&eli->li_list_mtx);
3135                                         n = pos->next;
3136                                 }
3137                                 up_read((&elr->lr_super->s_umount));
3138                         }
3139                         /* error, remove the lazy_init job */
3140                         if (err) {
3141                                 ext4_remove_li_request(elr);
3142                                 continue;
3143                         }
3144                         if (!progress) {
3145                                 elr->lr_next_sched = jiffies +
3146                                         (prandom_u32()
3147                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3148                         }
3149                         if (time_before(elr->lr_next_sched, next_wakeup))
3150                                 next_wakeup = elr->lr_next_sched;
3151                 }
3152                 mutex_unlock(&eli->li_list_mtx);
3153
3154                 try_to_freeze();
3155
3156                 cur = jiffies;
3157                 if ((time_after_eq(cur, next_wakeup)) ||
3158                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3159                         cond_resched();
3160                         continue;
3161                 }
3162
3163                 schedule_timeout_interruptible(next_wakeup - cur);
3164
3165                 if (kthread_should_stop()) {
3166                         ext4_clear_request_list();
3167                         goto exit_thread;
3168                 }
3169         }
3170
3171 exit_thread:
3172         /*
3173          * It looks like the request list is empty, but we need
3174          * to check it under the li_list_mtx lock, to prevent any
3175          * additions into it, and of course we should lock ext4_li_mtx
3176          * to atomically free the list and ext4_li_info, because at
3177          * this point another ext4 filesystem could be registering
3178          * new one.
3179          */
3180         mutex_lock(&ext4_li_mtx);
3181         mutex_lock(&eli->li_list_mtx);
3182         if (!list_empty(&eli->li_request_list)) {
3183                 mutex_unlock(&eli->li_list_mtx);
3184                 mutex_unlock(&ext4_li_mtx);
3185                 goto cont_thread;
3186         }
3187         mutex_unlock(&eli->li_list_mtx);
3188         kfree(ext4_li_info);
3189         ext4_li_info = NULL;
3190         mutex_unlock(&ext4_li_mtx);
3191
3192         return 0;
3193 }
3194
3195 static void ext4_clear_request_list(void)
3196 {
3197         struct list_head *pos, *n;
3198         struct ext4_li_request *elr;
3199
3200         mutex_lock(&ext4_li_info->li_list_mtx);
3201         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3202                 elr = list_entry(pos, struct ext4_li_request,
3203                                  lr_request);
3204                 ext4_remove_li_request(elr);
3205         }
3206         mutex_unlock(&ext4_li_info->li_list_mtx);
3207 }
3208
3209 static int ext4_run_lazyinit_thread(void)
3210 {
3211         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3212                                          ext4_li_info, "ext4lazyinit");
3213         if (IS_ERR(ext4_lazyinit_task)) {
3214                 int err = PTR_ERR(ext4_lazyinit_task);
3215                 ext4_clear_request_list();
3216                 kfree(ext4_li_info);
3217                 ext4_li_info = NULL;
3218                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3219                                  "initialization thread\n",
3220                                  err);
3221                 return err;
3222         }
3223         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3224         return 0;
3225 }
3226
3227 /*
3228  * Check whether it make sense to run itable init. thread or not.
3229  * If there is at least one uninitialized inode table, return
3230  * corresponding group number, else the loop goes through all
3231  * groups and return total number of groups.
3232  */
3233 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3234 {
3235         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3236         struct ext4_group_desc *gdp = NULL;
3237
3238         if (!ext4_has_group_desc_csum(sb))
3239                 return ngroups;
3240
3241         for (group = 0; group < ngroups; group++) {
3242                 gdp = ext4_get_group_desc(sb, group, NULL);
3243                 if (!gdp)
3244                         continue;
3245
3246                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3247                         break;
3248         }
3249
3250         return group;
3251 }
3252
3253 static int ext4_li_info_new(void)
3254 {
3255         struct ext4_lazy_init *eli = NULL;
3256
3257         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3258         if (!eli)
3259                 return -ENOMEM;
3260
3261         INIT_LIST_HEAD(&eli->li_request_list);
3262         mutex_init(&eli->li_list_mtx);
3263
3264         eli->li_state |= EXT4_LAZYINIT_QUIT;
3265
3266         ext4_li_info = eli;
3267
3268         return 0;
3269 }
3270
3271 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3272                                             ext4_group_t start)
3273 {
3274         struct ext4_sb_info *sbi = EXT4_SB(sb);
3275         struct ext4_li_request *elr;
3276
3277         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3278         if (!elr)
3279                 return NULL;
3280
3281         elr->lr_super = sb;
3282         elr->lr_sbi = sbi;
3283         elr->lr_next_group = start;
3284
3285         /*
3286          * Randomize first schedule time of the request to
3287          * spread the inode table initialization requests
3288          * better.
3289          */
3290         elr->lr_next_sched = jiffies + (prandom_u32() %
3291                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3292         return elr;
3293 }
3294
3295 int ext4_register_li_request(struct super_block *sb,
3296                              ext4_group_t first_not_zeroed)
3297 {
3298         struct ext4_sb_info *sbi = EXT4_SB(sb);
3299         struct ext4_li_request *elr = NULL;
3300         ext4_group_t ngroups = sbi->s_groups_count;
3301         int ret = 0;
3302
3303         mutex_lock(&ext4_li_mtx);
3304         if (sbi->s_li_request != NULL) {
3305                 /*
3306                  * Reset timeout so it can be computed again, because
3307                  * s_li_wait_mult might have changed.
3308                  */
3309                 sbi->s_li_request->lr_timeout = 0;
3310                 goto out;
3311         }
3312
3313         if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3314             !test_opt(sb, INIT_INODE_TABLE))
3315                 goto out;
3316
3317         elr = ext4_li_request_new(sb, first_not_zeroed);
3318         if (!elr) {
3319                 ret = -ENOMEM;
3320                 goto out;
3321         }
3322
3323         if (NULL == ext4_li_info) {
3324                 ret = ext4_li_info_new();
3325                 if (ret)
3326                         goto out;
3327         }
3328
3329         mutex_lock(&ext4_li_info->li_list_mtx);
3330         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3331         mutex_unlock(&ext4_li_info->li_list_mtx);
3332
3333         sbi->s_li_request = elr;
3334         /*
3335          * set elr to NULL here since it has been inserted to
3336          * the request_list and the removal and free of it is
3337          * handled by ext4_clear_request_list from now on.
3338          */
3339         elr = NULL;
3340
3341         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3342                 ret = ext4_run_lazyinit_thread();
3343                 if (ret)
3344                         goto out;
3345         }
3346 out:
3347         mutex_unlock(&ext4_li_mtx);
3348         if (ret)
3349                 kfree(elr);
3350         return ret;
3351 }
3352
3353 /*
3354  * We do not need to lock anything since this is called on
3355  * module unload.
3356  */
3357 static void ext4_destroy_lazyinit_thread(void)
3358 {
3359         /*
3360          * If thread exited earlier
3361          * there's nothing to be done.
3362          */
3363         if (!ext4_li_info || !ext4_lazyinit_task)
3364                 return;
3365
3366         kthread_stop(ext4_lazyinit_task);
3367 }
3368
3369 static int set_journal_csum_feature_set(struct super_block *sb)
3370 {
3371         int ret = 1;
3372         int compat, incompat;
3373         struct ext4_sb_info *sbi = EXT4_SB(sb);
3374
3375         if (ext4_has_metadata_csum(sb)) {
3376                 /* journal checksum v3 */
3377                 compat = 0;
3378                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3379         } else {
3380                 /* journal checksum v1 */
3381                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3382                 incompat = 0;
3383         }
3384
3385         jbd2_journal_clear_features(sbi->s_journal,
3386                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3387                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3388                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3389         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3390                 ret = jbd2_journal_set_features(sbi->s_journal,
3391                                 compat, 0,
3392                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3393                                 incompat);
3394         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3395                 ret = jbd2_journal_set_features(sbi->s_journal,
3396                                 compat, 0,
3397                                 incompat);
3398                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3399                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3400         } else {
3401                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3402                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3403         }
3404
3405         return ret;
3406 }
3407
3408 /*
3409  * Note: calculating the overhead so we can be compatible with
3410  * historical BSD practice is quite difficult in the face of
3411  * clusters/bigalloc.  This is because multiple metadata blocks from
3412  * different block group can end up in the same allocation cluster.
3413  * Calculating the exact overhead in the face of clustered allocation
3414  * requires either O(all block bitmaps) in memory or O(number of block
3415  * groups**2) in time.  We will still calculate the superblock for
3416  * older file systems --- and if we come across with a bigalloc file
3417  * system with zero in s_overhead_clusters the estimate will be close to
3418  * correct especially for very large cluster sizes --- but for newer
3419  * file systems, it's better to calculate this figure once at mkfs
3420  * time, and store it in the superblock.  If the superblock value is
3421  * present (even for non-bigalloc file systems), we will use it.
3422  */
3423 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3424                           char *buf)
3425 {
3426         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3427         struct ext4_group_desc  *gdp;
3428         ext4_fsblk_t            first_block, last_block, b;
3429         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3430         int                     s, j, count = 0;
3431
3432         if (!ext4_has_feature_bigalloc(sb))
3433                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3434                         sbi->s_itb_per_group + 2);
3435
3436         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3437                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3438         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3439         for (i = 0; i < ngroups; i++) {
3440                 gdp = ext4_get_group_desc(sb, i, NULL);
3441                 b = ext4_block_bitmap(sb, gdp);
3442                 if (b >= first_block && b <= last_block) {
3443                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3444                         count++;
3445                 }
3446                 b = ext4_inode_bitmap(sb, gdp);
3447                 if (b >= first_block && b <= last_block) {
3448                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3449                         count++;
3450                 }
3451                 b = ext4_inode_table(sb, gdp);
3452                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3453                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3454                                 int c = EXT4_B2C(sbi, b - first_block);
3455                                 ext4_set_bit(c, buf);
3456                                 count++;
3457                         }
3458                 if (i != grp)
3459                         continue;
3460                 s = 0;
3461                 if (ext4_bg_has_super(sb, grp)) {
3462                         ext4_set_bit(s++, buf);
3463                         count++;
3464                 }
3465                 j = ext4_bg_num_gdb(sb, grp);
3466                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3467                         ext4_error(sb, "Invalid number of block group "
3468                                    "descriptor blocks: %d", j);
3469                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3470                 }
3471                 count += j;
3472                 for (; j > 0; j--)
3473                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3474         }
3475         if (!count)
3476                 return 0;
3477         return EXT4_CLUSTERS_PER_GROUP(sb) -
3478                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3479 }
3480
3481 /*
3482  * Compute the overhead and stash it in sbi->s_overhead
3483  */
3484 int ext4_calculate_overhead(struct super_block *sb)
3485 {
3486         struct ext4_sb_info *sbi = EXT4_SB(sb);
3487         struct ext4_super_block *es = sbi->s_es;
3488         struct inode *j_inode;
3489         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3490         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3491         ext4_fsblk_t overhead = 0;
3492         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3493
3494         if (!buf)
3495                 return -ENOMEM;
3496
3497         /*
3498          * Compute the overhead (FS structures).  This is constant
3499          * for a given filesystem unless the number of block groups
3500          * changes so we cache the previous value until it does.
3501          */
3502
3503         /*
3504          * All of the blocks before first_data_block are overhead
3505          */
3506         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3507
3508         /*
3509          * Add the overhead found in each block group
3510          */
3511         for (i = 0; i < ngroups; i++) {
3512                 int blks;
3513
3514                 blks = count_overhead(sb, i, buf);
3515                 overhead += blks;
3516                 if (blks)
3517                         memset(buf, 0, PAGE_SIZE);
3518                 cond_resched();
3519         }
3520
3521         /*
3522          * Add the internal journal blocks whether the journal has been
3523          * loaded or not
3524          */
3525         if (sbi->s_journal && !sbi->journal_bdev)
3526                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3527         else if (ext4_has_feature_journal(sb) && !sbi->s_journal) {
3528                 j_inode = ext4_get_journal_inode(sb, j_inum);
3529                 if (j_inode) {
3530                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3531                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3532                         iput(j_inode);
3533                 } else {
3534                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3535                 }
3536         }
3537         sbi->s_overhead = overhead;
3538         smp_wmb();
3539         free_page((unsigned long) buf);
3540         return 0;
3541 }
3542
3543 static void ext4_clamp_want_extra_isize(struct super_block *sb)
3544 {
3545         struct ext4_sb_info *sbi = EXT4_SB(sb);
3546         struct ext4_super_block *es = sbi->s_es;
3547
3548         /* determine the minimum size of new large inodes, if present */
3549         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE &&
3550             sbi->s_want_extra_isize == 0) {
3551                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3552                                                      EXT4_GOOD_OLD_INODE_SIZE;
3553                 if (ext4_has_feature_extra_isize(sb)) {
3554                         if (sbi->s_want_extra_isize <
3555                             le16_to_cpu(es->s_want_extra_isize))
3556                                 sbi->s_want_extra_isize =
3557                                         le16_to_cpu(es->s_want_extra_isize);
3558                         if (sbi->s_want_extra_isize <
3559                             le16_to_cpu(es->s_min_extra_isize))
3560                                 sbi->s_want_extra_isize =
3561                                         le16_to_cpu(es->s_min_extra_isize);
3562                 }
3563         }
3564         /* Check if enough inode space is available */
3565         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3566                                                         sbi->s_inode_size) {
3567                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3568                                                        EXT4_GOOD_OLD_INODE_SIZE;
3569                 ext4_msg(sb, KERN_INFO,
3570                          "required extra inode space not available");
3571         }
3572 }
3573
3574 static void ext4_set_resv_clusters(struct super_block *sb)
3575 {
3576         ext4_fsblk_t resv_clusters;
3577         struct ext4_sb_info *sbi = EXT4_SB(sb);
3578
3579         /*
3580          * There's no need to reserve anything when we aren't using extents.
3581          * The space estimates are exact, there are no unwritten extents,
3582          * hole punching doesn't need new metadata... This is needed especially
3583          * to keep ext2/3 backward compatibility.
3584          */
3585         if (!ext4_has_feature_extents(sb))
3586                 return;
3587         /*
3588          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3589          * This should cover the situations where we can not afford to run
3590          * out of space like for example punch hole, or converting
3591          * unwritten extents in delalloc path. In most cases such
3592          * allocation would require 1, or 2 blocks, higher numbers are
3593          * very rare.
3594          */
3595         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3596                          sbi->s_cluster_bits);
3597
3598         do_div(resv_clusters, 50);
3599         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3600
3601         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3602 }
3603
3604 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3605 {
3606         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3607         char *orig_data = kstrdup(data, GFP_KERNEL);
3608         struct buffer_head *bh;
3609         struct ext4_super_block *es = NULL;
3610         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3611         ext4_fsblk_t block;
3612         ext4_fsblk_t sb_block = get_sb_block(&data);
3613         ext4_fsblk_t logical_sb_block;
3614         unsigned long offset = 0;
3615         unsigned long journal_devnum = 0;
3616         unsigned long def_mount_opts;
3617         struct inode *root;
3618         const char *descr;
3619         int ret = -ENOMEM;
3620         int blocksize, clustersize;
3621         unsigned int db_count;
3622         unsigned int i;
3623         int needs_recovery, has_huge_files, has_bigalloc;
3624         __u64 blocks_count;
3625         int err = 0;
3626         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3627         ext4_group_t first_not_zeroed;
3628
3629         if ((data && !orig_data) || !sbi)
3630                 goto out_free_base;
3631
3632         sbi->s_daxdev = dax_dev;
3633         sbi->s_blockgroup_lock =
3634                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3635         if (!sbi->s_blockgroup_lock)
3636                 goto out_free_base;
3637
3638         sb->s_fs_info = sbi;
3639         sbi->s_sb = sb;
3640         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3641         sbi->s_sb_block = sb_block;
3642         if (sb->s_bdev->bd_part)
3643                 sbi->s_sectors_written_start =
3644                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
3645
3646         /* Cleanup superblock name */
3647         strreplace(sb->s_id, '/', '!');
3648
3649         /* -EINVAL is default */
3650         ret = -EINVAL;
3651         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3652         if (!blocksize) {
3653                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3654                 goto out_fail;
3655         }
3656
3657         /*
3658          * The ext4 superblock will not be buffer aligned for other than 1kB
3659          * block sizes.  We need to calculate the offset from buffer start.
3660          */
3661         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3662                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3663                 offset = do_div(logical_sb_block, blocksize);
3664         } else {
3665                 logical_sb_block = sb_block;
3666         }
3667
3668         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3669                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3670                 goto out_fail;
3671         }
3672         /*
3673          * Note: s_es must be initialized as soon as possible because
3674          *       some ext4 macro-instructions depend on its value
3675          */
3676         es = (struct ext4_super_block *) (bh->b_data + offset);
3677         sbi->s_es = es;
3678         sb->s_magic = le16_to_cpu(es->s_magic);
3679         if (sb->s_magic != EXT4_SUPER_MAGIC)
3680                 goto cantfind_ext4;
3681         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3682
3683         /* Warn if metadata_csum and gdt_csum are both set. */
3684         if (ext4_has_feature_metadata_csum(sb) &&
3685             ext4_has_feature_gdt_csum(sb))
3686                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3687                              "redundant flags; please run fsck.");
3688
3689         /* Check for a known checksum algorithm */
3690         if (!ext4_verify_csum_type(sb, es)) {
3691                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3692                          "unknown checksum algorithm.");
3693                 silent = 1;
3694                 goto cantfind_ext4;
3695         }
3696
3697         /* Load the checksum driver */
3698         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3699         if (IS_ERR(sbi->s_chksum_driver)) {
3700                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3701                 ret = PTR_ERR(sbi->s_chksum_driver);
3702                 sbi->s_chksum_driver = NULL;
3703                 goto failed_mount;
3704         }
3705
3706         /* Check superblock checksum */
3707         if (!ext4_superblock_csum_verify(sb, es)) {
3708                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3709                          "invalid superblock checksum.  Run e2fsck?");
3710                 silent = 1;
3711                 ret = -EFSBADCRC;
3712                 goto cantfind_ext4;
3713         }
3714
3715         /* Precompute checksum seed for all metadata */
3716         if (ext4_has_feature_csum_seed(sb))
3717                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3718         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3719                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3720                                                sizeof(es->s_uuid));
3721
3722         /* Set defaults before we parse the mount options */
3723         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3724         set_opt(sb, INIT_INODE_TABLE);
3725         if (def_mount_opts & EXT4_DEFM_DEBUG)
3726                 set_opt(sb, DEBUG);
3727         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3728                 set_opt(sb, GRPID);
3729         if (def_mount_opts & EXT4_DEFM_UID16)
3730                 set_opt(sb, NO_UID32);
3731         /* xattr user namespace & acls are now defaulted on */
3732         set_opt(sb, XATTR_USER);
3733 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3734         set_opt(sb, POSIX_ACL);
3735 #endif
3736         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3737         if (ext4_has_metadata_csum(sb))
3738                 set_opt(sb, JOURNAL_CHECKSUM);
3739
3740         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3741                 set_opt(sb, JOURNAL_DATA);
3742         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3743                 set_opt(sb, ORDERED_DATA);
3744         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3745                 set_opt(sb, WRITEBACK_DATA);
3746
3747         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3748                 set_opt(sb, ERRORS_PANIC);
3749         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3750                 set_opt(sb, ERRORS_CONT);
3751         else
3752                 set_opt(sb, ERRORS_RO);
3753         /* block_validity enabled by default; disable with noblock_validity */
3754         set_opt(sb, BLOCK_VALIDITY);
3755         if (def_mount_opts & EXT4_DEFM_DISCARD)
3756                 set_opt(sb, DISCARD);
3757
3758         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3759         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3760         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3761         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3762         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3763
3764         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3765                 set_opt(sb, BARRIER);
3766
3767         /*
3768          * enable delayed allocation by default
3769          * Use -o nodelalloc to turn it off
3770          */
3771         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3772             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3773                 set_opt(sb, DELALLOC);
3774
3775         /*
3776          * set default s_li_wait_mult for lazyinit, for the case there is
3777          * no mount option specified.
3778          */
3779         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3780
3781         if (sbi->s_es->s_mount_opts[0]) {
3782                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3783                                               sizeof(sbi->s_es->s_mount_opts),
3784                                               GFP_KERNEL);
3785                 if (!s_mount_opts)
3786                         goto failed_mount;
3787                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
3788                                    &journal_ioprio, 0)) {
3789                         ext4_msg(sb, KERN_WARNING,
3790                                  "failed to parse options in superblock: %s",
3791                                  s_mount_opts);
3792                 }
3793                 kfree(s_mount_opts);
3794         }
3795         sbi->s_def_mount_opt = sbi->s_mount_opt;
3796         if (!parse_options((char *) data, sb, &journal_devnum,
3797                            &journal_ioprio, 0))
3798                 goto failed_mount;
3799
3800 #ifdef CONFIG_UNICODE
3801         if (ext4_has_feature_casefold(sb) && !sbi->s_encoding) {
3802                 const struct ext4_sb_encodings *encoding_info;
3803                 struct unicode_map *encoding;
3804                 __u16 encoding_flags;
3805
3806                 if (ext4_has_feature_encrypt(sb)) {
3807                         ext4_msg(sb, KERN_ERR,
3808                                  "Can't mount with encoding and encryption");
3809                         goto failed_mount;
3810                 }
3811
3812                 if (ext4_sb_read_encoding(es, &encoding_info,
3813                                           &encoding_flags)) {
3814                         ext4_msg(sb, KERN_ERR,
3815                                  "Encoding requested by superblock is unknown");
3816                         goto failed_mount;
3817                 }
3818
3819                 encoding = utf8_load(encoding_info->version);
3820                 if (IS_ERR(encoding)) {
3821                         ext4_msg(sb, KERN_ERR,
3822                                  "can't mount with superblock charset: %s-%s "
3823                                  "not supported by the kernel. flags: 0x%x.",
3824                                  encoding_info->name, encoding_info->version,
3825                                  encoding_flags);
3826                         goto failed_mount;
3827                 }
3828                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
3829                          "%s-%s with flags 0x%hx", encoding_info->name,
3830                          encoding_info->version?:"\b", encoding_flags);
3831
3832                 sbi->s_encoding = encoding;
3833                 sbi->s_encoding_flags = encoding_flags;
3834         }
3835 #endif
3836
3837         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3838                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3839                             "with data=journal disables delayed "
3840                             "allocation and O_DIRECT support!\n");
3841                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3842                         ext4_msg(sb, KERN_ERR, "can't mount with "
3843                                  "both data=journal and delalloc");
3844                         goto failed_mount;
3845                 }
3846                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3847                         ext4_msg(sb, KERN_ERR, "can't mount with "
3848                                  "both data=journal and dioread_nolock");
3849                         goto failed_mount;
3850                 }
3851                 if (test_opt(sb, DAX)) {
3852                         ext4_msg(sb, KERN_ERR, "can't mount with "
3853                                  "both data=journal and dax");
3854                         goto failed_mount;
3855                 }
3856                 if (ext4_has_feature_encrypt(sb)) {
3857                         ext4_msg(sb, KERN_WARNING,
3858                                  "encrypted files will use data=ordered "
3859                                  "instead of data journaling mode");
3860                 }
3861                 if (test_opt(sb, DELALLOC))
3862                         clear_opt(sb, DELALLOC);
3863         } else {
3864                 sb->s_iflags |= SB_I_CGROUPWB;
3865         }
3866
3867         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
3868                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
3869
3870         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3871             (ext4_has_compat_features(sb) ||
3872              ext4_has_ro_compat_features(sb) ||
3873              ext4_has_incompat_features(sb)))
3874                 ext4_msg(sb, KERN_WARNING,
3875                        "feature flags set on rev 0 fs, "
3876                        "running e2fsck is recommended");
3877
3878         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3879                 set_opt2(sb, HURD_COMPAT);
3880                 if (ext4_has_feature_64bit(sb)) {
3881                         ext4_msg(sb, KERN_ERR,
3882                                  "The Hurd can't support 64-bit file systems");
3883                         goto failed_mount;
3884                 }
3885
3886                 /*
3887                  * ea_inode feature uses l_i_version field which is not
3888                  * available in HURD_COMPAT mode.
3889                  */
3890                 if (ext4_has_feature_ea_inode(sb)) {
3891                         ext4_msg(sb, KERN_ERR,
3892                                  "ea_inode feature is not supported for Hurd");
3893                         goto failed_mount;
3894                 }
3895         }
3896
3897         if (IS_EXT2_SB(sb)) {
3898                 if (ext2_feature_set_ok(sb))
3899                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3900                                  "using the ext4 subsystem");
3901                 else {
3902                         /*
3903                          * If we're probing be silent, if this looks like
3904                          * it's actually an ext[34] filesystem.
3905                          */
3906                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3907                                 goto failed_mount;
3908                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3909                                  "to feature incompatibilities");
3910                         goto failed_mount;
3911                 }
3912         }
3913
3914         if (IS_EXT3_SB(sb)) {
3915                 if (ext3_feature_set_ok(sb))
3916                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3917                                  "using the ext4 subsystem");
3918                 else {
3919                         /*
3920                          * If we're probing be silent, if this looks like
3921                          * it's actually an ext4 filesystem.
3922                          */
3923                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3924                                 goto failed_mount;
3925                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3926                                  "to feature incompatibilities");
3927                         goto failed_mount;
3928                 }
3929         }
3930
3931         /*
3932          * Check feature flags regardless of the revision level, since we
3933          * previously didn't change the revision level when setting the flags,
3934          * so there is a chance incompat flags are set on a rev 0 filesystem.
3935          */
3936         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
3937                 goto failed_mount;
3938
3939         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3940         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3941             blocksize > EXT4_MAX_BLOCK_SIZE) {
3942                 ext4_msg(sb, KERN_ERR,
3943                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3944                          blocksize, le32_to_cpu(es->s_log_block_size));
3945                 goto failed_mount;
3946         }
3947         if (le32_to_cpu(es->s_log_block_size) >
3948             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3949                 ext4_msg(sb, KERN_ERR,
3950                          "Invalid log block size: %u",
3951                          le32_to_cpu(es->s_log_block_size));
3952                 goto failed_mount;
3953         }
3954         if (le32_to_cpu(es->s_log_cluster_size) >
3955             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3956                 ext4_msg(sb, KERN_ERR,
3957                          "Invalid log cluster size: %u",
3958                          le32_to_cpu(es->s_log_cluster_size));
3959                 goto failed_mount;
3960         }
3961
3962         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
3963                 ext4_msg(sb, KERN_ERR,
3964                          "Number of reserved GDT blocks insanely large: %d",
3965                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
3966                 goto failed_mount;
3967         }
3968
3969         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3970                 if (ext4_has_feature_inline_data(sb)) {
3971                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
3972                                         " that may contain inline data");
3973                         goto failed_mount;
3974                 }
3975                 if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
3976                         ext4_msg(sb, KERN_ERR,
3977                                 "DAX unsupported by block device.");
3978                         goto failed_mount;
3979                 }
3980         }
3981
3982         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
3983                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
3984                          es->s_encryption_level);
3985                 goto failed_mount;
3986         }
3987
3988         if (sb->s_blocksize != blocksize) {
3989                 /* Validate the filesystem blocksize */
3990                 if (!sb_set_blocksize(sb, blocksize)) {
3991                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3992                                         blocksize);
3993                         goto failed_mount;
3994                 }
3995
3996                 brelse(bh);
3997                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3998                 offset = do_div(logical_sb_block, blocksize);
3999                 bh = sb_bread_unmovable(sb, logical_sb_block);
4000                 if (!bh) {
4001                         ext4_msg(sb, KERN_ERR,
4002                                "Can't read superblock on 2nd try");
4003                         goto failed_mount;
4004                 }
4005                 es = (struct ext4_super_block *)(bh->b_data + offset);
4006                 sbi->s_es = es;
4007                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4008                         ext4_msg(sb, KERN_ERR,
4009                                "Magic mismatch, very weird!");
4010                         goto failed_mount;
4011                 }
4012         }
4013
4014         has_huge_files = ext4_has_feature_huge_file(sb);
4015         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4016                                                       has_huge_files);
4017         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4018
4019         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4020                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4021                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4022         } else {
4023                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4024                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4025                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4026                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4027                                  sbi->s_first_ino);
4028                         goto failed_mount;
4029                 }
4030                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4031                     (!is_power_of_2(sbi->s_inode_size)) ||
4032                     (sbi->s_inode_size > blocksize)) {
4033                         ext4_msg(sb, KERN_ERR,
4034                                "unsupported inode size: %d",
4035                                sbi->s_inode_size);
4036                         goto failed_mount;
4037                 }
4038                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
4039                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
4040         }
4041
4042         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4043         if (ext4_has_feature_64bit(sb)) {
4044                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4045                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4046                     !is_power_of_2(sbi->s_desc_size)) {
4047                         ext4_msg(sb, KERN_ERR,
4048                                "unsupported descriptor size %lu",
4049                                sbi->s_desc_size);
4050                         goto failed_mount;
4051                 }
4052         } else
4053                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4054
4055         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4056         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4057
4058         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4059         if (sbi->s_inodes_per_block == 0)
4060                 goto cantfind_ext4;
4061         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4062             sbi->s_inodes_per_group > blocksize * 8) {
4063                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4064                          sbi->s_blocks_per_group);
4065                 goto failed_mount;
4066         }
4067         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4068                                         sbi->s_inodes_per_block;
4069         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4070         sbi->s_sbh = bh;
4071         sbi->s_mount_state = le16_to_cpu(es->s_state);
4072         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4073         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4074
4075         for (i = 0; i < 4; i++)
4076                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4077         sbi->s_def_hash_version = es->s_def_hash_version;
4078         if (ext4_has_feature_dir_index(sb)) {
4079                 i = le32_to_cpu(es->s_flags);
4080                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4081                         sbi->s_hash_unsigned = 3;
4082                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4083 #ifdef __CHAR_UNSIGNED__
4084                         if (!sb_rdonly(sb))
4085                                 es->s_flags |=
4086                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4087                         sbi->s_hash_unsigned = 3;
4088 #else
4089                         if (!sb_rdonly(sb))
4090                                 es->s_flags |=
4091                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4092 #endif
4093                 }
4094         }
4095
4096         /* Handle clustersize */
4097         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4098         has_bigalloc = ext4_has_feature_bigalloc(sb);
4099         if (has_bigalloc) {
4100                 if (clustersize < blocksize) {
4101                         ext4_msg(sb, KERN_ERR,
4102                                  "cluster size (%d) smaller than "
4103                                  "block size (%d)", clustersize, blocksize);
4104                         goto failed_mount;
4105                 }
4106                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4107                         le32_to_cpu(es->s_log_block_size);
4108                 sbi->s_clusters_per_group =
4109                         le32_to_cpu(es->s_clusters_per_group);
4110                 if (sbi->s_clusters_per_group > blocksize * 8) {
4111                         ext4_msg(sb, KERN_ERR,
4112                                  "#clusters per group too big: %lu",
4113                                  sbi->s_clusters_per_group);
4114                         goto failed_mount;
4115                 }
4116                 if (sbi->s_blocks_per_group !=
4117                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4118                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4119                                  "clusters per group (%lu) inconsistent",
4120                                  sbi->s_blocks_per_group,
4121                                  sbi->s_clusters_per_group);
4122                         goto failed_mount;
4123                 }
4124         } else {
4125                 if (clustersize != blocksize) {
4126                         ext4_msg(sb, KERN_ERR,
4127                                  "fragment/cluster size (%d) != "
4128                                  "block size (%d)", clustersize, blocksize);
4129                         goto failed_mount;
4130                 }
4131                 if (sbi->s_blocks_per_group > blocksize * 8) {
4132                         ext4_msg(sb, KERN_ERR,
4133                                  "#blocks per group too big: %lu",
4134                                  sbi->s_blocks_per_group);
4135                         goto failed_mount;
4136                 }
4137                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4138                 sbi->s_cluster_bits = 0;
4139         }
4140         sbi->s_cluster_ratio = clustersize / blocksize;
4141
4142         /* Do we have standard group size of clustersize * 8 blocks ? */
4143         if (sbi->s_blocks_per_group == clustersize << 3)
4144                 set_opt2(sb, STD_GROUP_SIZE);
4145
4146         /*
4147          * Test whether we have more sectors than will fit in sector_t,
4148          * and whether the max offset is addressable by the page cache.
4149          */
4150         err = generic_check_addressable(sb->s_blocksize_bits,
4151                                         ext4_blocks_count(es));
4152         if (err) {
4153                 ext4_msg(sb, KERN_ERR, "filesystem"
4154                          " too large to mount safely on this system");
4155                 goto failed_mount;
4156         }
4157
4158         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4159                 goto cantfind_ext4;
4160
4161         /* check blocks count against device size */
4162         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4163         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4164                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4165                        "exceeds size of device (%llu blocks)",
4166                        ext4_blocks_count(es), blocks_count);
4167                 goto failed_mount;
4168         }
4169
4170         /*
4171          * It makes no sense for the first data block to be beyond the end
4172          * of the filesystem.
4173          */
4174         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4175                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4176                          "block %u is beyond end of filesystem (%llu)",
4177                          le32_to_cpu(es->s_first_data_block),
4178                          ext4_blocks_count(es));
4179                 goto failed_mount;
4180         }
4181         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4182             (sbi->s_cluster_ratio == 1)) {
4183                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4184                          "block is 0 with a 1k block and cluster size");
4185                 goto failed_mount;
4186         }
4187
4188         blocks_count = (ext4_blocks_count(es) -
4189                         le32_to_cpu(es->s_first_data_block) +
4190                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4191         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4192         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4193                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
4194                        "(block count %llu, first data block %u, "
4195                        "blocks per group %lu)", sbi->s_groups_count,
4196                        ext4_blocks_count(es),
4197                        le32_to_cpu(es->s_first_data_block),
4198                        EXT4_BLOCKS_PER_GROUP(sb));
4199                 goto failed_mount;
4200         }
4201         sbi->s_groups_count = blocks_count;
4202         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4203                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4204         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4205             le32_to_cpu(es->s_inodes_count)) {
4206                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4207                          le32_to_cpu(es->s_inodes_count),
4208                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4209                 ret = -EINVAL;
4210                 goto failed_mount;
4211         }
4212         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4213                    EXT4_DESC_PER_BLOCK(sb);
4214         if (ext4_has_feature_meta_bg(sb)) {
4215                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4216                         ext4_msg(sb, KERN_WARNING,
4217                                  "first meta block group too large: %u "
4218                                  "(group descriptor block count %u)",
4219                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4220                         goto failed_mount;
4221                 }
4222         }
4223         sbi->s_group_desc = kvmalloc_array(db_count,
4224                                            sizeof(struct buffer_head *),
4225                                            GFP_KERNEL);
4226         if (sbi->s_group_desc == NULL) {
4227                 ext4_msg(sb, KERN_ERR, "not enough memory");
4228                 ret = -ENOMEM;
4229                 goto failed_mount;
4230         }
4231
4232         bgl_lock_init(sbi->s_blockgroup_lock);
4233
4234         /* Pre-read the descriptors into the buffer cache */
4235         for (i = 0; i < db_count; i++) {
4236                 block = descriptor_loc(sb, logical_sb_block, i);
4237                 sb_breadahead(sb, block);
4238         }
4239
4240         for (i = 0; i < db_count; i++) {
4241                 block = descriptor_loc(sb, logical_sb_block, i);
4242                 sbi->s_group_desc[i] = sb_bread_unmovable(sb, block);
4243                 if (!sbi->s_group_desc[i]) {
4244                         ext4_msg(sb, KERN_ERR,
4245                                "can't read group descriptor %d", i);
4246                         db_count = i;
4247                         goto failed_mount2;
4248                 }
4249         }
4250         sbi->s_gdb_count = db_count;
4251         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4252                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4253                 ret = -EFSCORRUPTED;
4254                 goto failed_mount2;
4255         }
4256
4257         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4258
4259         /* Register extent status tree shrinker */
4260         if (ext4_es_register_shrinker(sbi))
4261                 goto failed_mount3;
4262
4263         sbi->s_stripe = ext4_get_stripe_size(sbi);
4264         sbi->s_extent_max_zeroout_kb = 32;
4265
4266         /*
4267          * set up enough so that it can read an inode
4268          */
4269         sb->s_op = &ext4_sops;
4270         sb->s_export_op = &ext4_export_ops;
4271         sb->s_xattr = ext4_xattr_handlers;
4272 #ifdef CONFIG_FS_ENCRYPTION
4273         sb->s_cop = &ext4_cryptops;
4274 #endif
4275 #ifdef CONFIG_QUOTA
4276         sb->dq_op = &ext4_quota_operations;
4277         if (ext4_has_feature_quota(sb))
4278                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4279         else
4280                 sb->s_qcop = &ext4_qctl_operations;
4281         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4282 #endif
4283         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4284
4285         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4286         mutex_init(&sbi->s_orphan_lock);
4287
4288         sb->s_root = NULL;
4289
4290         needs_recovery = (es->s_last_orphan != 0 ||
4291                           ext4_has_feature_journal_needs_recovery(sb));
4292
4293         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4294                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4295                         goto failed_mount3a;
4296
4297         /*
4298          * The first inode we look at is the journal inode.  Don't try
4299          * root first: it may be modified in the journal!
4300          */
4301         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4302                 err = ext4_load_journal(sb, es, journal_devnum);
4303                 if (err)
4304                         goto failed_mount3a;
4305         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4306                    ext4_has_feature_journal_needs_recovery(sb)) {
4307                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4308                        "suppressed and not mounted read-only");
4309                 goto failed_mount_wq;
4310         } else {
4311                 /* Nojournal mode, all journal mount options are illegal */
4312                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4313                         ext4_msg(sb, KERN_ERR, "can't mount with "
4314                                  "journal_checksum, fs mounted w/o journal");
4315                         goto failed_mount_wq;
4316                 }
4317                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4318                         ext4_msg(sb, KERN_ERR, "can't mount with "
4319                                  "journal_async_commit, fs mounted w/o journal");
4320                         goto failed_mount_wq;
4321                 }
4322                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4323                         ext4_msg(sb, KERN_ERR, "can't mount with "
4324                                  "commit=%lu, fs mounted w/o journal",
4325                                  sbi->s_commit_interval / HZ);
4326                         goto failed_mount_wq;
4327                 }
4328                 if (EXT4_MOUNT_DATA_FLAGS &
4329                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4330                         ext4_msg(sb, KERN_ERR, "can't mount with "
4331                                  "data=, fs mounted w/o journal");
4332                         goto failed_mount_wq;
4333                 }
4334                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4335                 clear_opt(sb, JOURNAL_CHECKSUM);
4336                 clear_opt(sb, DATA_FLAGS);
4337                 sbi->s_journal = NULL;
4338                 needs_recovery = 0;
4339                 goto no_journal;
4340         }
4341
4342         if (ext4_has_feature_64bit(sb) &&
4343             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4344                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4345                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4346                 goto failed_mount_wq;
4347         }
4348
4349         if (!set_journal_csum_feature_set(sb)) {
4350                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4351                          "feature set");
4352                 goto failed_mount_wq;
4353         }
4354
4355         /* We have now updated the journal if required, so we can
4356          * validate the data journaling mode. */
4357         switch (test_opt(sb, DATA_FLAGS)) {
4358         case 0:
4359                 /* No mode set, assume a default based on the journal
4360                  * capabilities: ORDERED_DATA if the journal can
4361                  * cope, else JOURNAL_DATA
4362                  */
4363                 if (jbd2_journal_check_available_features
4364                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4365                         set_opt(sb, ORDERED_DATA);
4366                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4367                 } else {
4368                         set_opt(sb, JOURNAL_DATA);
4369                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4370                 }
4371                 break;
4372
4373         case EXT4_MOUNT_ORDERED_DATA:
4374         case EXT4_MOUNT_WRITEBACK_DATA:
4375                 if (!jbd2_journal_check_available_features
4376                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4377                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4378                                "requested data journaling mode");
4379                         goto failed_mount_wq;
4380                 }
4381         default:
4382                 break;
4383         }
4384
4385         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4386             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4387                 ext4_msg(sb, KERN_ERR, "can't mount with "
4388                         "journal_async_commit in data=ordered mode");
4389                 goto failed_mount_wq;
4390         }
4391
4392         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4393
4394         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4395
4396 no_journal:
4397         if (!test_opt(sb, NO_MBCACHE)) {
4398                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4399                 if (!sbi->s_ea_block_cache) {
4400                         ext4_msg(sb, KERN_ERR,
4401                                  "Failed to create ea_block_cache");
4402                         goto failed_mount_wq;
4403                 }
4404
4405                 if (ext4_has_feature_ea_inode(sb)) {
4406                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4407                         if (!sbi->s_ea_inode_cache) {
4408                                 ext4_msg(sb, KERN_ERR,
4409                                          "Failed to create ea_inode_cache");
4410                                 goto failed_mount_wq;
4411                         }
4412                 }
4413         }
4414
4415         if ((DUMMY_ENCRYPTION_ENABLED(sbi) || ext4_has_feature_encrypt(sb)) &&
4416             (blocksize != PAGE_SIZE)) {
4417                 ext4_msg(sb, KERN_ERR,
4418                          "Unsupported blocksize for fs encryption");
4419                 goto failed_mount_wq;
4420         }
4421
4422         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4423             !ext4_has_feature_encrypt(sb)) {
4424                 ext4_set_feature_encrypt(sb);
4425                 ext4_commit_super(sb, 1);
4426         }
4427
4428         /*
4429          * Get the # of file system overhead blocks from the
4430          * superblock if present.
4431          */
4432         if (es->s_overhead_clusters)
4433                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4434         else {
4435                 err = ext4_calculate_overhead(sb);
4436                 if (err)
4437                         goto failed_mount_wq;
4438         }
4439
4440         /*
4441          * The maximum number of concurrent works can be high and
4442          * concurrency isn't really necessary.  Limit it to 1.
4443          */
4444         EXT4_SB(sb)->rsv_conversion_wq =
4445                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4446         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4447                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4448                 ret = -ENOMEM;
4449                 goto failed_mount4;
4450         }
4451
4452         /*
4453          * The jbd2_journal_load will have done any necessary log recovery,
4454          * so we can safely mount the rest of the filesystem now.
4455          */
4456
4457         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4458         if (IS_ERR(root)) {
4459                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4460                 ret = PTR_ERR(root);
4461                 root = NULL;
4462                 goto failed_mount4;
4463         }
4464         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4465                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4466                 iput(root);
4467                 goto failed_mount4;
4468         }
4469
4470 #ifdef CONFIG_UNICODE
4471         if (sbi->s_encoding)
4472                 sb->s_d_op = &ext4_dentry_ops;
4473 #endif
4474
4475         sb->s_root = d_make_root(root);
4476         if (!sb->s_root) {
4477                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4478                 ret = -ENOMEM;
4479                 goto failed_mount4;
4480         }
4481
4482         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4483         if (ret == -EROFS) {
4484                 sb->s_flags |= SB_RDONLY;
4485                 ret = 0;
4486         } else if (ret)
4487                 goto failed_mount4a;
4488
4489         ext4_clamp_want_extra_isize(sb);
4490
4491         ext4_set_resv_clusters(sb);
4492
4493         err = ext4_setup_system_zone(sb);
4494         if (err) {
4495                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4496                          "zone (%d)", err);
4497                 goto failed_mount4a;
4498         }
4499
4500         ext4_ext_init(sb);
4501         err = ext4_mb_init(sb);
4502         if (err) {
4503                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4504                          err);
4505                 goto failed_mount5;
4506         }
4507
4508         block = ext4_count_free_clusters(sb);
4509         ext4_free_blocks_count_set(sbi->s_es,
4510                                    EXT4_C2B(sbi, block));
4511         ext4_superblock_csum_set(sb);
4512         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4513                                   GFP_KERNEL);
4514         if (!err) {
4515                 unsigned long freei = ext4_count_free_inodes(sb);
4516                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4517                 ext4_superblock_csum_set(sb);
4518                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4519                                           GFP_KERNEL);
4520         }
4521         if (!err)
4522                 err = percpu_counter_init(&sbi->s_dirs_counter,
4523                                           ext4_count_dirs(sb), GFP_KERNEL);
4524         if (!err)
4525                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4526                                           GFP_KERNEL);
4527         if (!err)
4528                 err = percpu_init_rwsem(&sbi->s_journal_flag_rwsem);
4529
4530         if (err) {
4531                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4532                 goto failed_mount6;
4533         }
4534
4535         if (ext4_has_feature_flex_bg(sb))
4536                 if (!ext4_fill_flex_info(sb)) {
4537                         ext4_msg(sb, KERN_ERR,
4538                                "unable to initialize "
4539                                "flex_bg meta info!");
4540                         goto failed_mount6;
4541                 }
4542
4543         err = ext4_register_li_request(sb, first_not_zeroed);
4544         if (err)
4545                 goto failed_mount6;
4546
4547         err = ext4_register_sysfs(sb);
4548         if (err)
4549                 goto failed_mount7;
4550
4551 #ifdef CONFIG_QUOTA
4552         /* Enable quota usage during mount. */
4553         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4554                 err = ext4_enable_quotas(sb);
4555                 if (err)
4556                         goto failed_mount8;
4557         }
4558 #endif  /* CONFIG_QUOTA */
4559
4560         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4561         ext4_orphan_cleanup(sb, es);
4562         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4563         if (needs_recovery) {
4564                 ext4_msg(sb, KERN_INFO, "recovery complete");
4565                 ext4_mark_recovery_complete(sb, es);
4566         }
4567         if (EXT4_SB(sb)->s_journal) {
4568                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4569                         descr = " journalled data mode";
4570                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4571                         descr = " ordered data mode";
4572                 else
4573                         descr = " writeback data mode";
4574         } else
4575                 descr = "out journal";
4576
4577         if (test_opt(sb, DISCARD)) {
4578                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4579                 if (!blk_queue_discard(q))
4580                         ext4_msg(sb, KERN_WARNING,
4581                                  "mounting with \"discard\" option, but "
4582                                  "the device does not support discard");
4583         }
4584
4585         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4586                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4587                          "Opts: %.*s%s%s", descr,
4588                          (int) sizeof(sbi->s_es->s_mount_opts),
4589                          sbi->s_es->s_mount_opts,
4590                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4591
4592         if (es->s_error_count)
4593                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4594
4595         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4596         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4597         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4598         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4599
4600         kfree(orig_data);
4601         return 0;
4602
4603 cantfind_ext4:
4604         if (!silent)
4605                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4606         goto failed_mount;
4607
4608 #ifdef CONFIG_QUOTA
4609 failed_mount8:
4610         ext4_unregister_sysfs(sb);
4611 #endif
4612 failed_mount7:
4613         ext4_unregister_li_request(sb);
4614 failed_mount6:
4615         ext4_mb_release(sb);
4616         if (sbi->s_flex_groups)
4617                 kvfree(sbi->s_flex_groups);
4618         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4619         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4620         percpu_counter_destroy(&sbi->s_dirs_counter);
4621         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4622         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
4623 failed_mount5:
4624         ext4_ext_release(sb);
4625         ext4_release_system_zone(sb);
4626 failed_mount4a:
4627         dput(sb->s_root);
4628         sb->s_root = NULL;
4629 failed_mount4:
4630         ext4_msg(sb, KERN_ERR, "mount failed");
4631         if (EXT4_SB(sb)->rsv_conversion_wq)
4632                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4633 failed_mount_wq:
4634         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4635         sbi->s_ea_inode_cache = NULL;
4636
4637         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4638         sbi->s_ea_block_cache = NULL;
4639
4640         if (sbi->s_journal) {
4641                 jbd2_journal_destroy(sbi->s_journal);
4642                 sbi->s_journal = NULL;
4643         }
4644 failed_mount3a:
4645         ext4_es_unregister_shrinker(sbi);
4646 failed_mount3:
4647         del_timer_sync(&sbi->s_err_report);
4648         if (sbi->s_mmp_tsk)
4649                 kthread_stop(sbi->s_mmp_tsk);
4650 failed_mount2:
4651         for (i = 0; i < db_count; i++)
4652                 brelse(sbi->s_group_desc[i]);
4653         kvfree(sbi->s_group_desc);
4654 failed_mount:
4655         if (sbi->s_chksum_driver)
4656                 crypto_free_shash(sbi->s_chksum_driver);
4657
4658 #ifdef CONFIG_UNICODE
4659         utf8_unload(sbi->s_encoding);
4660 #endif
4661
4662 #ifdef CONFIG_QUOTA
4663         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4664                 kfree(get_qf_name(sb, sbi, i));
4665 #endif
4666         ext4_blkdev_remove(sbi);
4667         brelse(bh);
4668 out_fail:
4669         sb->s_fs_info = NULL;
4670         kfree(sbi->s_blockgroup_lock);
4671 out_free_base:
4672         kfree(sbi);
4673         kfree(orig_data);
4674         fs_put_dax(dax_dev);
4675         return err ? err : ret;
4676 }
4677
4678 /*
4679  * Setup any per-fs journal parameters now.  We'll do this both on
4680  * initial mount, once the journal has been initialised but before we've
4681  * done any recovery; and again on any subsequent remount.
4682  */
4683 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4684 {
4685         struct ext4_sb_info *sbi = EXT4_SB(sb);
4686
4687         journal->j_commit_interval = sbi->s_commit_interval;
4688         journal->j_min_batch_time = sbi->s_min_batch_time;
4689         journal->j_max_batch_time = sbi->s_max_batch_time;
4690
4691         write_lock(&journal->j_state_lock);
4692         if (test_opt(sb, BARRIER))
4693                 journal->j_flags |= JBD2_BARRIER;
4694         else
4695                 journal->j_flags &= ~JBD2_BARRIER;
4696         if (test_opt(sb, DATA_ERR_ABORT))
4697                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4698         else
4699                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4700         write_unlock(&journal->j_state_lock);
4701 }
4702
4703 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4704                                              unsigned int journal_inum)
4705 {
4706         struct inode *journal_inode;
4707
4708         /*
4709          * Test for the existence of a valid inode on disk.  Bad things
4710          * happen if we iget() an unused inode, as the subsequent iput()
4711          * will try to delete it.
4712          */
4713         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
4714         if (IS_ERR(journal_inode)) {
4715                 ext4_msg(sb, KERN_ERR, "no journal found");
4716                 return NULL;
4717         }
4718         if (!journal_inode->i_nlink) {
4719                 make_bad_inode(journal_inode);
4720                 iput(journal_inode);
4721                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4722                 return NULL;
4723         }
4724
4725         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4726                   journal_inode, journal_inode->i_size);
4727         if (!S_ISREG(journal_inode->i_mode)) {
4728                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4729                 iput(journal_inode);
4730                 return NULL;
4731         }
4732         return journal_inode;
4733 }
4734
4735 static journal_t *ext4_get_journal(struct super_block *sb,
4736                                    unsigned int journal_inum)
4737 {
4738         struct inode *journal_inode;
4739         journal_t *journal;
4740
4741         BUG_ON(!ext4_has_feature_journal(sb));
4742
4743         journal_inode = ext4_get_journal_inode(sb, journal_inum);
4744         if (!journal_inode)
4745                 return NULL;
4746
4747         journal = jbd2_journal_init_inode(journal_inode);
4748         if (!journal) {
4749                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4750                 iput(journal_inode);
4751                 return NULL;
4752         }
4753         journal->j_private = sb;
4754         ext4_init_journal_params(sb, journal);
4755         return journal;
4756 }
4757
4758 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4759                                        dev_t j_dev)
4760 {
4761         struct buffer_head *bh;
4762         journal_t *journal;
4763         ext4_fsblk_t start;
4764         ext4_fsblk_t len;
4765         int hblock, blocksize;
4766         ext4_fsblk_t sb_block;
4767         unsigned long offset;
4768         struct ext4_super_block *es;
4769         struct block_device *bdev;
4770
4771         BUG_ON(!ext4_has_feature_journal(sb));
4772
4773         bdev = ext4_blkdev_get(j_dev, sb);
4774         if (bdev == NULL)
4775                 return NULL;
4776
4777         blocksize = sb->s_blocksize;
4778         hblock = bdev_logical_block_size(bdev);
4779         if (blocksize < hblock) {
4780                 ext4_msg(sb, KERN_ERR,
4781                         "blocksize too small for journal device");
4782                 goto out_bdev;
4783         }
4784
4785         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4786         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4787         set_blocksize(bdev, blocksize);
4788         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4789                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4790                        "external journal");
4791                 goto out_bdev;
4792         }
4793
4794         es = (struct ext4_super_block *) (bh->b_data + offset);
4795         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4796             !(le32_to_cpu(es->s_feature_incompat) &
4797               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4798                 ext4_msg(sb, KERN_ERR, "external journal has "
4799                                         "bad superblock");
4800                 brelse(bh);
4801                 goto out_bdev;
4802         }
4803
4804         if ((le32_to_cpu(es->s_feature_ro_compat) &
4805              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4806             es->s_checksum != ext4_superblock_csum(sb, es)) {
4807                 ext4_msg(sb, KERN_ERR, "external journal has "
4808                                        "corrupt superblock");
4809                 brelse(bh);
4810                 goto out_bdev;
4811         }
4812
4813         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4814                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4815                 brelse(bh);
4816                 goto out_bdev;
4817         }
4818
4819         len = ext4_blocks_count(es);
4820         start = sb_block + 1;
4821         brelse(bh);     /* we're done with the superblock */
4822
4823         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4824                                         start, len, blocksize);
4825         if (!journal) {
4826                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4827                 goto out_bdev;
4828         }
4829         journal->j_private = sb;
4830         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4831         wait_on_buffer(journal->j_sb_buffer);
4832         if (!buffer_uptodate(journal->j_sb_buffer)) {
4833                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4834                 goto out_journal;
4835         }
4836         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4837                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4838                                         "user (unsupported) - %d",
4839                         be32_to_cpu(journal->j_superblock->s_nr_users));
4840                 goto out_journal;
4841         }
4842         EXT4_SB(sb)->journal_bdev = bdev;
4843         ext4_init_journal_params(sb, journal);
4844         return journal;
4845
4846 out_journal:
4847         jbd2_journal_destroy(journal);
4848 out_bdev:
4849         ext4_blkdev_put(bdev);
4850         return NULL;
4851 }
4852
4853 static int ext4_load_journal(struct super_block *sb,
4854                              struct ext4_super_block *es,
4855                              unsigned long journal_devnum)
4856 {
4857         journal_t *journal;
4858         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4859         dev_t journal_dev;
4860         int err = 0;
4861         int really_read_only;
4862
4863         BUG_ON(!ext4_has_feature_journal(sb));
4864
4865         if (journal_devnum &&
4866             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4867                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4868                         "numbers have changed");
4869                 journal_dev = new_decode_dev(journal_devnum);
4870         } else
4871                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4872
4873         really_read_only = bdev_read_only(sb->s_bdev);
4874
4875         /*
4876          * Are we loading a blank journal or performing recovery after a
4877          * crash?  For recovery, we need to check in advance whether we
4878          * can get read-write access to the device.
4879          */
4880         if (ext4_has_feature_journal_needs_recovery(sb)) {
4881                 if (sb_rdonly(sb)) {
4882                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4883                                         "required on readonly filesystem");
4884                         if (really_read_only) {
4885                                 ext4_msg(sb, KERN_ERR, "write access "
4886                                         "unavailable, cannot proceed "
4887                                         "(try mounting with noload)");
4888                                 return -EROFS;
4889                         }
4890                         ext4_msg(sb, KERN_INFO, "write access will "
4891                                "be enabled during recovery");
4892                 }
4893         }
4894
4895         if (journal_inum && journal_dev) {
4896                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4897                        "and inode journals!");
4898                 return -EINVAL;
4899         }
4900
4901         if (journal_inum) {
4902                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4903                         return -EINVAL;
4904         } else {
4905                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4906                         return -EINVAL;
4907         }
4908
4909         if (!(journal->j_flags & JBD2_BARRIER))
4910                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4911
4912         if (!ext4_has_feature_journal_needs_recovery(sb))
4913                 err = jbd2_journal_wipe(journal, !really_read_only);
4914         if (!err) {
4915                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4916                 if (save)
4917                         memcpy(save, ((char *) es) +
4918                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4919                 err = jbd2_journal_load(journal);
4920                 if (save)
4921                         memcpy(((char *) es) + EXT4_S_ERR_START,
4922                                save, EXT4_S_ERR_LEN);
4923                 kfree(save);
4924         }
4925
4926         if (err) {
4927                 ext4_msg(sb, KERN_ERR, "error loading journal");
4928                 jbd2_journal_destroy(journal);
4929                 return err;
4930         }
4931
4932         EXT4_SB(sb)->s_journal = journal;
4933         ext4_clear_journal_err(sb, es);
4934
4935         if (!really_read_only && journal_devnum &&
4936             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4937                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4938
4939                 /* Make sure we flush the recovery flag to disk. */
4940                 ext4_commit_super(sb, 1);
4941         }
4942
4943         return 0;
4944 }
4945
4946 static int ext4_commit_super(struct super_block *sb, int sync)
4947 {
4948         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4949         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4950         int error = 0;
4951
4952         if (!sbh || block_device_ejected(sb))
4953                 return error;
4954
4955         /*
4956          * The superblock bh should be mapped, but it might not be if the
4957          * device was hot-removed. Not much we can do but fail the I/O.
4958          */
4959         if (!buffer_mapped(sbh))
4960                 return error;
4961
4962         /*
4963          * If the file system is mounted read-only, don't update the
4964          * superblock write time.  This avoids updating the superblock
4965          * write time when we are mounting the root file system
4966          * read/only but we need to replay the journal; at that point,
4967          * for people who are east of GMT and who make their clock
4968          * tick in localtime for Windows bug-for-bug compatibility,
4969          * the clock is set in the future, and this will cause e2fsck
4970          * to complain and force a full file system check.
4971          */
4972         if (!(sb->s_flags & SB_RDONLY))
4973                 ext4_update_tstamp(es, s_wtime);
4974         if (sb->s_bdev->bd_part)
4975                 es->s_kbytes_written =
4976                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4977                             ((part_stat_read(sb->s_bdev->bd_part,
4978                                              sectors[STAT_WRITE]) -
4979                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4980         else
4981                 es->s_kbytes_written =
4982                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4983         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
4984                 ext4_free_blocks_count_set(es,
4985                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4986                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4987         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
4988                 es->s_free_inodes_count =
4989                         cpu_to_le32(percpu_counter_sum_positive(
4990                                 &EXT4_SB(sb)->s_freeinodes_counter));
4991         BUFFER_TRACE(sbh, "marking dirty");
4992         ext4_superblock_csum_set(sb);
4993         if (sync)
4994                 lock_buffer(sbh);
4995         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
4996                 /*
4997                  * Oh, dear.  A previous attempt to write the
4998                  * superblock failed.  This could happen because the
4999                  * USB device was yanked out.  Or it could happen to
5000                  * be a transient write error and maybe the block will
5001                  * be remapped.  Nothing we can do but to retry the
5002                  * write and hope for the best.
5003                  */
5004                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5005                        "superblock detected");
5006                 clear_buffer_write_io_error(sbh);
5007                 set_buffer_uptodate(sbh);
5008         }
5009         mark_buffer_dirty(sbh);
5010         if (sync) {
5011                 unlock_buffer(sbh);
5012                 error = __sync_dirty_buffer(sbh,
5013                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5014                 if (buffer_write_io_error(sbh)) {
5015                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5016                                "superblock");
5017                         clear_buffer_write_io_error(sbh);
5018                         set_buffer_uptodate(sbh);
5019                 }
5020         }
5021         return error;
5022 }
5023
5024 /*
5025  * Have we just finished recovery?  If so, and if we are mounting (or
5026  * remounting) the filesystem readonly, then we will end up with a
5027  * consistent fs on disk.  Record that fact.
5028  */
5029 static void ext4_mark_recovery_complete(struct super_block *sb,
5030                                         struct ext4_super_block *es)
5031 {
5032         journal_t *journal = EXT4_SB(sb)->s_journal;
5033
5034         if (!ext4_has_feature_journal(sb)) {
5035                 BUG_ON(journal != NULL);
5036                 return;
5037         }
5038         jbd2_journal_lock_updates(journal);
5039         if (jbd2_journal_flush(journal) < 0)
5040                 goto out;
5041
5042         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5043                 ext4_clear_feature_journal_needs_recovery(sb);
5044                 ext4_commit_super(sb, 1);
5045         }
5046
5047 out:
5048         jbd2_journal_unlock_updates(journal);
5049 }
5050
5051 /*
5052  * If we are mounting (or read-write remounting) a filesystem whose journal
5053  * has recorded an error from a previous lifetime, move that error to the
5054  * main filesystem now.
5055  */
5056 static void ext4_clear_journal_err(struct super_block *sb,
5057                                    struct ext4_super_block *es)
5058 {
5059         journal_t *journal;
5060         int j_errno;
5061         const char *errstr;
5062
5063         BUG_ON(!ext4_has_feature_journal(sb));
5064
5065         journal = EXT4_SB(sb)->s_journal;
5066
5067         /*
5068          * Now check for any error status which may have been recorded in the
5069          * journal by a prior ext4_error() or ext4_abort()
5070          */
5071
5072         j_errno = jbd2_journal_errno(journal);
5073         if (j_errno) {
5074                 char nbuf[16];
5075
5076                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5077                 ext4_warning(sb, "Filesystem error recorded "
5078                              "from previous mount: %s", errstr);
5079                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5080
5081                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5082                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5083                 ext4_commit_super(sb, 1);
5084
5085                 jbd2_journal_clear_err(journal);
5086                 jbd2_journal_update_sb_errno(journal);
5087         }
5088 }
5089
5090 /*
5091  * Force the running and committing transactions to commit,
5092  * and wait on the commit.
5093  */
5094 int ext4_force_commit(struct super_block *sb)
5095 {
5096         journal_t *journal;
5097
5098         if (sb_rdonly(sb))
5099                 return 0;
5100
5101         journal = EXT4_SB(sb)->s_journal;
5102         return ext4_journal_force_commit(journal);
5103 }
5104
5105 static int ext4_sync_fs(struct super_block *sb, int wait)
5106 {
5107         int ret = 0;
5108         tid_t target;
5109         bool needs_barrier = false;
5110         struct ext4_sb_info *sbi = EXT4_SB(sb);
5111
5112         if (unlikely(ext4_forced_shutdown(sbi)))
5113                 return 0;
5114
5115         trace_ext4_sync_fs(sb, wait);
5116         flush_workqueue(sbi->rsv_conversion_wq);
5117         /*
5118          * Writeback quota in non-journalled quota case - journalled quota has
5119          * no dirty dquots
5120          */
5121         dquot_writeback_dquots(sb, -1);
5122         /*
5123          * Data writeback is possible w/o journal transaction, so barrier must
5124          * being sent at the end of the function. But we can skip it if
5125          * transaction_commit will do it for us.
5126          */
5127         if (sbi->s_journal) {
5128                 target = jbd2_get_latest_transaction(sbi->s_journal);
5129                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5130                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5131                         needs_barrier = true;
5132
5133                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5134                         if (wait)
5135                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5136                                                            target);
5137                 }
5138         } else if (wait && test_opt(sb, BARRIER))
5139                 needs_barrier = true;
5140         if (needs_barrier) {
5141                 int err;
5142                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
5143                 if (!ret)
5144                         ret = err;
5145         }
5146
5147         return ret;
5148 }
5149
5150 /*
5151  * LVM calls this function before a (read-only) snapshot is created.  This
5152  * gives us a chance to flush the journal completely and mark the fs clean.
5153  *
5154  * Note that only this function cannot bring a filesystem to be in a clean
5155  * state independently. It relies on upper layer to stop all data & metadata
5156  * modifications.
5157  */
5158 static int ext4_freeze(struct super_block *sb)
5159 {
5160         int error = 0;
5161         journal_t *journal;
5162
5163         if (sb_rdonly(sb))
5164                 return 0;
5165
5166         journal = EXT4_SB(sb)->s_journal;
5167
5168         if (journal) {
5169                 /* Now we set up the journal barrier. */
5170                 jbd2_journal_lock_updates(journal);
5171
5172                 /*
5173                  * Don't clear the needs_recovery flag if we failed to
5174                  * flush the journal.
5175                  */
5176                 error = jbd2_journal_flush(journal);
5177                 if (error < 0)
5178                         goto out;
5179
5180                 /* Journal blocked and flushed, clear needs_recovery flag. */
5181                 ext4_clear_feature_journal_needs_recovery(sb);
5182         }
5183
5184         error = ext4_commit_super(sb, 1);
5185 out:
5186         if (journal)
5187                 /* we rely on upper layer to stop further updates */
5188                 jbd2_journal_unlock_updates(journal);
5189         return error;
5190 }
5191
5192 /*
5193  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5194  * flag here, even though the filesystem is not technically dirty yet.
5195  */
5196 static int ext4_unfreeze(struct super_block *sb)
5197 {
5198         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5199                 return 0;
5200
5201         if (EXT4_SB(sb)->s_journal) {
5202                 /* Reset the needs_recovery flag before the fs is unlocked. */
5203                 ext4_set_feature_journal_needs_recovery(sb);
5204         }
5205
5206         ext4_commit_super(sb, 1);
5207         return 0;
5208 }
5209
5210 /*
5211  * Structure to save mount options for ext4_remount's benefit
5212  */
5213 struct ext4_mount_options {
5214         unsigned long s_mount_opt;
5215         unsigned long s_mount_opt2;
5216         kuid_t s_resuid;
5217         kgid_t s_resgid;
5218         unsigned long s_commit_interval;
5219         u32 s_min_batch_time, s_max_batch_time;
5220 #ifdef CONFIG_QUOTA
5221         int s_jquota_fmt;
5222         char *s_qf_names[EXT4_MAXQUOTAS];
5223 #endif
5224 };
5225
5226 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5227 {
5228         struct ext4_super_block *es;
5229         struct ext4_sb_info *sbi = EXT4_SB(sb);
5230         unsigned long old_sb_flags;
5231         struct ext4_mount_options old_opts;
5232         int enable_quota = 0;
5233         ext4_group_t g;
5234         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5235         int err = 0;
5236 #ifdef CONFIG_QUOTA
5237         int i, j;
5238         char *to_free[EXT4_MAXQUOTAS];
5239 #endif
5240         char *orig_data = kstrdup(data, GFP_KERNEL);
5241
5242         if (data && !orig_data)
5243                 return -ENOMEM;
5244
5245         /* Store the original options */
5246         old_sb_flags = sb->s_flags;
5247         old_opts.s_mount_opt = sbi->s_mount_opt;
5248         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5249         old_opts.s_resuid = sbi->s_resuid;
5250         old_opts.s_resgid = sbi->s_resgid;
5251         old_opts.s_commit_interval = sbi->s_commit_interval;
5252         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5253         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5254 #ifdef CONFIG_QUOTA
5255         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5256         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5257                 if (sbi->s_qf_names[i]) {
5258                         char *qf_name = get_qf_name(sb, sbi, i);
5259
5260                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5261                         if (!old_opts.s_qf_names[i]) {
5262                                 for (j = 0; j < i; j++)
5263                                         kfree(old_opts.s_qf_names[j]);
5264                                 kfree(orig_data);
5265                                 return -ENOMEM;
5266                         }
5267                 } else
5268                         old_opts.s_qf_names[i] = NULL;
5269 #endif
5270         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5271                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5272
5273         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5274                 err = -EINVAL;
5275                 goto restore_opts;
5276         }
5277
5278         ext4_clamp_want_extra_isize(sb);
5279
5280         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5281             test_opt(sb, JOURNAL_CHECKSUM)) {
5282                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5283                          "during remount not supported; ignoring");
5284                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5285         }
5286
5287         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5288                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5289                         ext4_msg(sb, KERN_ERR, "can't mount with "
5290                                  "both data=journal and delalloc");
5291                         err = -EINVAL;
5292                         goto restore_opts;
5293                 }
5294                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5295                         ext4_msg(sb, KERN_ERR, "can't mount with "
5296                                  "both data=journal and dioread_nolock");
5297                         err = -EINVAL;
5298                         goto restore_opts;
5299                 }
5300                 if (test_opt(sb, DAX)) {
5301                         ext4_msg(sb, KERN_ERR, "can't mount with "
5302                                  "both data=journal and dax");
5303                         err = -EINVAL;
5304                         goto restore_opts;
5305                 }
5306         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5307                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5308                         ext4_msg(sb, KERN_ERR, "can't mount with "
5309                                 "journal_async_commit in data=ordered mode");
5310                         err = -EINVAL;
5311                         goto restore_opts;
5312                 }
5313         }
5314
5315         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5316                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5317                 err = -EINVAL;
5318                 goto restore_opts;
5319         }
5320
5321         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
5322                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
5323                         "dax flag with busy inodes while remounting");
5324                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
5325         }
5326
5327         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5328                 ext4_abort(sb, "Abort forced by user");
5329
5330         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5331                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5332
5333         es = sbi->s_es;
5334
5335         if (sbi->s_journal) {
5336                 ext4_init_journal_params(sb, sbi->s_journal);
5337                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5338         }
5339
5340         if (*flags & SB_LAZYTIME)
5341                 sb->s_flags |= SB_LAZYTIME;
5342
5343         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5344                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5345                         err = -EROFS;
5346                         goto restore_opts;
5347                 }
5348
5349                 if (*flags & SB_RDONLY) {
5350                         err = sync_filesystem(sb);
5351                         if (err < 0)
5352                                 goto restore_opts;
5353                         err = dquot_suspend(sb, -1);
5354                         if (err < 0)
5355                                 goto restore_opts;
5356
5357                         /*
5358                          * First of all, the unconditional stuff we have to do
5359                          * to disable replay of the journal when we next remount
5360                          */
5361                         sb->s_flags |= SB_RDONLY;
5362
5363                         /*
5364                          * OK, test if we are remounting a valid rw partition
5365                          * readonly, and if so set the rdonly flag and then
5366                          * mark the partition as valid again.
5367                          */
5368                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5369                             (sbi->s_mount_state & EXT4_VALID_FS))
5370                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5371
5372                         if (sbi->s_journal)
5373                                 ext4_mark_recovery_complete(sb, es);
5374                         if (sbi->s_mmp_tsk)
5375                                 kthread_stop(sbi->s_mmp_tsk);
5376                 } else {
5377                         /* Make sure we can mount this feature set readwrite */
5378                         if (ext4_has_feature_readonly(sb) ||
5379                             !ext4_feature_set_ok(sb, 0)) {
5380                                 err = -EROFS;
5381                                 goto restore_opts;
5382                         }
5383                         /*
5384                          * Make sure the group descriptor checksums
5385                          * are sane.  If they aren't, refuse to remount r/w.
5386                          */
5387                         for (g = 0; g < sbi->s_groups_count; g++) {
5388                                 struct ext4_group_desc *gdp =
5389                                         ext4_get_group_desc(sb, g, NULL);
5390
5391                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5392                                         ext4_msg(sb, KERN_ERR,
5393                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5394                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5395                                                le16_to_cpu(gdp->bg_checksum));
5396                                         err = -EFSBADCRC;
5397                                         goto restore_opts;
5398                                 }
5399                         }
5400
5401                         /*
5402                          * If we have an unprocessed orphan list hanging
5403                          * around from a previously readonly bdev mount,
5404                          * require a full umount/remount for now.
5405                          */
5406                         if (es->s_last_orphan) {
5407                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5408                                        "remount RDWR because of unprocessed "
5409                                        "orphan inode list.  Please "
5410                                        "umount/remount instead");
5411                                 err = -EINVAL;
5412                                 goto restore_opts;
5413                         }
5414
5415                         /*
5416                          * Mounting a RDONLY partition read-write, so reread
5417                          * and store the current valid flag.  (It may have
5418                          * been changed by e2fsck since we originally mounted
5419                          * the partition.)
5420                          */
5421                         if (sbi->s_journal)
5422                                 ext4_clear_journal_err(sb, es);
5423                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5424
5425                         err = ext4_setup_super(sb, es, 0);
5426                         if (err)
5427                                 goto restore_opts;
5428
5429                         sb->s_flags &= ~SB_RDONLY;
5430                         if (ext4_has_feature_mmp(sb))
5431                                 if (ext4_multi_mount_protect(sb,
5432                                                 le64_to_cpu(es->s_mmp_block))) {
5433                                         err = -EROFS;
5434                                         goto restore_opts;
5435                                 }
5436                         enable_quota = 1;
5437                 }
5438         }
5439
5440         /*
5441          * Reinitialize lazy itable initialization thread based on
5442          * current settings
5443          */
5444         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5445                 ext4_unregister_li_request(sb);
5446         else {
5447                 ext4_group_t first_not_zeroed;
5448                 first_not_zeroed = ext4_has_uninit_itable(sb);
5449                 ext4_register_li_request(sb, first_not_zeroed);
5450         }
5451
5452         ext4_setup_system_zone(sb);
5453         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5454                 err = ext4_commit_super(sb, 1);
5455                 if (err)
5456                         goto restore_opts;
5457         }
5458
5459 #ifdef CONFIG_QUOTA
5460         /* Release old quota file names */
5461         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5462                 kfree(old_opts.s_qf_names[i]);
5463         if (enable_quota) {
5464                 if (sb_any_quota_suspended(sb))
5465                         dquot_resume(sb, -1);
5466                 else if (ext4_has_feature_quota(sb)) {
5467                         err = ext4_enable_quotas(sb);
5468                         if (err)
5469                                 goto restore_opts;
5470                 }
5471         }
5472 #endif
5473
5474         *flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME);
5475         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5476         kfree(orig_data);
5477         return 0;
5478
5479 restore_opts:
5480         sb->s_flags = old_sb_flags;
5481         sbi->s_mount_opt = old_opts.s_mount_opt;
5482         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5483         sbi->s_resuid = old_opts.s_resuid;
5484         sbi->s_resgid = old_opts.s_resgid;
5485         sbi->s_commit_interval = old_opts.s_commit_interval;
5486         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5487         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5488 #ifdef CONFIG_QUOTA
5489         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5490         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5491                 to_free[i] = get_qf_name(sb, sbi, i);
5492                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
5493         }
5494         synchronize_rcu();
5495         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5496                 kfree(to_free[i]);
5497 #endif
5498         kfree(orig_data);
5499         return err;
5500 }
5501
5502 #ifdef CONFIG_QUOTA
5503 static int ext4_statfs_project(struct super_block *sb,
5504                                kprojid_t projid, struct kstatfs *buf)
5505 {
5506         struct kqid qid;
5507         struct dquot *dquot;
5508         u64 limit;
5509         u64 curblock;
5510
5511         qid = make_kqid_projid(projid);
5512         dquot = dqget(sb, qid);
5513         if (IS_ERR(dquot))
5514                 return PTR_ERR(dquot);
5515         spin_lock(&dquot->dq_dqb_lock);
5516
5517         limit = (dquot->dq_dqb.dqb_bsoftlimit ?
5518                  dquot->dq_dqb.dqb_bsoftlimit :
5519                  dquot->dq_dqb.dqb_bhardlimit) >> sb->s_blocksize_bits;
5520         if (limit && buf->f_blocks > limit) {
5521                 curblock = (dquot->dq_dqb.dqb_curspace +
5522                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5523                 buf->f_blocks = limit;
5524                 buf->f_bfree = buf->f_bavail =
5525                         (buf->f_blocks > curblock) ?
5526                          (buf->f_blocks - curblock) : 0;
5527         }
5528
5529         limit = dquot->dq_dqb.dqb_isoftlimit ?
5530                 dquot->dq_dqb.dqb_isoftlimit :
5531                 dquot->dq_dqb.dqb_ihardlimit;
5532         if (limit && buf->f_files > limit) {
5533                 buf->f_files = limit;
5534                 buf->f_ffree =
5535                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5536                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5537         }
5538
5539         spin_unlock(&dquot->dq_dqb_lock);
5540         dqput(dquot);
5541         return 0;
5542 }
5543 #endif
5544
5545 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5546 {
5547         struct super_block *sb = dentry->d_sb;
5548         struct ext4_sb_info *sbi = EXT4_SB(sb);
5549         struct ext4_super_block *es = sbi->s_es;
5550         ext4_fsblk_t overhead = 0, resv_blocks;
5551         u64 fsid;
5552         s64 bfree;
5553         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5554
5555         if (!test_opt(sb, MINIX_DF))
5556                 overhead = sbi->s_overhead;
5557
5558         buf->f_type = EXT4_SUPER_MAGIC;
5559         buf->f_bsize = sb->s_blocksize;
5560         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5561         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5562                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5563         /* prevent underflow in case that few free space is available */
5564         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5565         buf->f_bavail = buf->f_bfree -
5566                         (ext4_r_blocks_count(es) + resv_blocks);
5567         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5568                 buf->f_bavail = 0;
5569         buf->f_files = le32_to_cpu(es->s_inodes_count);
5570         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5571         buf->f_namelen = EXT4_NAME_LEN;
5572         fsid = le64_to_cpup((void *)es->s_uuid) ^
5573                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5574         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5575         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5576
5577 #ifdef CONFIG_QUOTA
5578         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5579             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5580                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5581 #endif
5582         return 0;
5583 }
5584
5585
5586 #ifdef CONFIG_QUOTA
5587
5588 /*
5589  * Helper functions so that transaction is started before we acquire dqio_sem
5590  * to keep correct lock ordering of transaction > dqio_sem
5591  */
5592 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5593 {
5594         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5595 }
5596
5597 static int ext4_write_dquot(struct dquot *dquot)
5598 {
5599         int ret, err;
5600         handle_t *handle;
5601         struct inode *inode;
5602
5603         inode = dquot_to_inode(dquot);
5604         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5605                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5606         if (IS_ERR(handle))
5607                 return PTR_ERR(handle);
5608         ret = dquot_commit(dquot);
5609         err = ext4_journal_stop(handle);
5610         if (!ret)
5611                 ret = err;
5612         return ret;
5613 }
5614
5615 static int ext4_acquire_dquot(struct dquot *dquot)
5616 {
5617         int ret, err;
5618         handle_t *handle;
5619
5620         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5621                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5622         if (IS_ERR(handle))
5623                 return PTR_ERR(handle);
5624         ret = dquot_acquire(dquot);
5625         err = ext4_journal_stop(handle);
5626         if (!ret)
5627                 ret = err;
5628         return ret;
5629 }
5630
5631 static int ext4_release_dquot(struct dquot *dquot)
5632 {
5633         int ret, err;
5634         handle_t *handle;
5635
5636         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5637                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5638         if (IS_ERR(handle)) {
5639                 /* Release dquot anyway to avoid endless cycle in dqput() */
5640                 dquot_release(dquot);
5641                 return PTR_ERR(handle);
5642         }
5643         ret = dquot_release(dquot);
5644         err = ext4_journal_stop(handle);
5645         if (!ret)
5646                 ret = err;
5647         return ret;
5648 }
5649
5650 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5651 {
5652         struct super_block *sb = dquot->dq_sb;
5653         struct ext4_sb_info *sbi = EXT4_SB(sb);
5654
5655         /* Are we journaling quotas? */
5656         if (ext4_has_feature_quota(sb) ||
5657             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5658                 dquot_mark_dquot_dirty(dquot);
5659                 return ext4_write_dquot(dquot);
5660         } else {
5661                 return dquot_mark_dquot_dirty(dquot);
5662         }
5663 }
5664
5665 static int ext4_write_info(struct super_block *sb, int type)
5666 {
5667         int ret, err;
5668         handle_t *handle;
5669
5670         /* Data block + inode block */
5671         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5672         if (IS_ERR(handle))
5673                 return PTR_ERR(handle);
5674         ret = dquot_commit_info(sb, type);
5675         err = ext4_journal_stop(handle);
5676         if (!ret)
5677                 ret = err;
5678         return ret;
5679 }
5680
5681 /*
5682  * Turn on quotas during mount time - we need to find
5683  * the quota file and such...
5684  */
5685 static int ext4_quota_on_mount(struct super_block *sb, int type)
5686 {
5687         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
5688                                         EXT4_SB(sb)->s_jquota_fmt, type);
5689 }
5690
5691 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5692 {
5693         struct ext4_inode_info *ei = EXT4_I(inode);
5694
5695         /* The first argument of lockdep_set_subclass has to be
5696          * *exactly* the same as the argument to init_rwsem() --- in
5697          * this case, in init_once() --- or lockdep gets unhappy
5698          * because the name of the lock is set using the
5699          * stringification of the argument to init_rwsem().
5700          */
5701         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
5702         lockdep_set_subclass(&ei->i_data_sem, subclass);
5703 }
5704
5705 /*
5706  * Standard function to be called on quota_on
5707  */
5708 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5709                          const struct path *path)
5710 {
5711         int err;
5712
5713         if (!test_opt(sb, QUOTA))
5714                 return -EINVAL;
5715
5716         /* Quotafile not on the same filesystem? */
5717         if (path->dentry->d_sb != sb)
5718                 return -EXDEV;
5719         /* Journaling quota? */
5720         if (EXT4_SB(sb)->s_qf_names[type]) {
5721                 /* Quotafile not in fs root? */
5722                 if (path->dentry->d_parent != sb->s_root)
5723                         ext4_msg(sb, KERN_WARNING,
5724                                 "Quota file not on filesystem root. "
5725                                 "Journaled quota will not work");
5726                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5727         } else {
5728                 /*
5729                  * Clear the flag just in case mount options changed since
5730                  * last time.
5731                  */
5732                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5733         }
5734
5735         /*
5736          * When we journal data on quota file, we have to flush journal to see
5737          * all updates to the file when we bypass pagecache...
5738          */
5739         if (EXT4_SB(sb)->s_journal &&
5740             ext4_should_journal_data(d_inode(path->dentry))) {
5741                 /*
5742                  * We don't need to lock updates but journal_flush() could
5743                  * otherwise be livelocked...
5744                  */
5745                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5746                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5747                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5748                 if (err)
5749                         return err;
5750         }
5751
5752         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5753         err = dquot_quota_on(sb, type, format_id, path);
5754         if (err) {
5755                 lockdep_set_quota_inode(path->dentry->d_inode,
5756                                              I_DATA_SEM_NORMAL);
5757         } else {
5758                 struct inode *inode = d_inode(path->dentry);
5759                 handle_t *handle;
5760
5761                 /*
5762                  * Set inode flags to prevent userspace from messing with quota
5763                  * files. If this fails, we return success anyway since quotas
5764                  * are already enabled and this is not a hard failure.
5765                  */
5766                 inode_lock(inode);
5767                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5768                 if (IS_ERR(handle))
5769                         goto unlock_inode;
5770                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5771                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5772                                 S_NOATIME | S_IMMUTABLE);
5773                 ext4_mark_inode_dirty(handle, inode);
5774                 ext4_journal_stop(handle);
5775         unlock_inode:
5776                 inode_unlock(inode);
5777         }
5778         return err;
5779 }
5780
5781 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5782                              unsigned int flags)
5783 {
5784         int err;
5785         struct inode *qf_inode;
5786         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5787                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5788                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5789                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5790         };
5791
5792         BUG_ON(!ext4_has_feature_quota(sb));
5793
5794         if (!qf_inums[type])
5795                 return -EPERM;
5796
5797         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
5798         if (IS_ERR(qf_inode)) {
5799                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5800                 return PTR_ERR(qf_inode);
5801         }
5802
5803         /* Don't account quota for quota files to avoid recursion */
5804         qf_inode->i_flags |= S_NOQUOTA;
5805         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5806         err = dquot_enable(qf_inode, type, format_id, flags);
5807         if (err)
5808                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5809         iput(qf_inode);
5810
5811         return err;
5812 }
5813
5814 /* Enable usage tracking for all quota types. */
5815 static int ext4_enable_quotas(struct super_block *sb)
5816 {
5817         int type, err = 0;
5818         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5819                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5820                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5821                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5822         };
5823         bool quota_mopt[EXT4_MAXQUOTAS] = {
5824                 test_opt(sb, USRQUOTA),
5825                 test_opt(sb, GRPQUOTA),
5826                 test_opt(sb, PRJQUOTA),
5827         };
5828
5829         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
5830         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5831                 if (qf_inums[type]) {
5832                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5833                                 DQUOT_USAGE_ENABLED |
5834                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5835                         if (err) {
5836                                 ext4_warning(sb,
5837                                         "Failed to enable quota tracking "
5838                                         "(type=%d, err=%d). Please run "
5839                                         "e2fsck to fix.", type, err);
5840                                 for (type--; type >= 0; type--)
5841                                         dquot_quota_off(sb, type);
5842
5843                                 return err;
5844                         }
5845                 }
5846         }
5847         return 0;
5848 }
5849
5850 static int ext4_quota_off(struct super_block *sb, int type)
5851 {
5852         struct inode *inode = sb_dqopt(sb)->files[type];
5853         handle_t *handle;
5854         int err;
5855
5856         /* Force all delayed allocation blocks to be allocated.
5857          * Caller already holds s_umount sem */
5858         if (test_opt(sb, DELALLOC))
5859                 sync_filesystem(sb);
5860
5861         if (!inode || !igrab(inode))
5862                 goto out;
5863
5864         err = dquot_quota_off(sb, type);
5865         if (err || ext4_has_feature_quota(sb))
5866                 goto out_put;
5867
5868         inode_lock(inode);
5869         /*
5870          * Update modification times of quota files when userspace can
5871          * start looking at them. If we fail, we return success anyway since
5872          * this is not a hard failure and quotas are already disabled.
5873          */
5874         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5875         if (IS_ERR(handle))
5876                 goto out_unlock;
5877         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
5878         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
5879         inode->i_mtime = inode->i_ctime = current_time(inode);
5880         ext4_mark_inode_dirty(handle, inode);
5881         ext4_journal_stop(handle);
5882 out_unlock:
5883         inode_unlock(inode);
5884 out_put:
5885         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
5886         iput(inode);
5887         return err;
5888 out:
5889         return dquot_quota_off(sb, type);
5890 }
5891
5892 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5893  * acquiring the locks... As quota files are never truncated and quota code
5894  * itself serializes the operations (and no one else should touch the files)
5895  * we don't have to be afraid of races */
5896 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5897                                size_t len, loff_t off)
5898 {
5899         struct inode *inode = sb_dqopt(sb)->files[type];
5900         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5901         int offset = off & (sb->s_blocksize - 1);
5902         int tocopy;
5903         size_t toread;
5904         struct buffer_head *bh;
5905         loff_t i_size = i_size_read(inode);
5906
5907         if (off > i_size)
5908                 return 0;
5909         if (off+len > i_size)
5910                 len = i_size-off;
5911         toread = len;
5912         while (toread > 0) {
5913                 tocopy = sb->s_blocksize - offset < toread ?
5914                                 sb->s_blocksize - offset : toread;
5915                 bh = ext4_bread(NULL, inode, blk, 0);
5916                 if (IS_ERR(bh))
5917                         return PTR_ERR(bh);
5918                 if (!bh)        /* A hole? */
5919                         memset(data, 0, tocopy);
5920                 else
5921                         memcpy(data, bh->b_data+offset, tocopy);
5922                 brelse(bh);
5923                 offset = 0;
5924                 toread -= tocopy;
5925                 data += tocopy;
5926                 blk++;
5927         }
5928         return len;
5929 }
5930
5931 /* Write to quotafile (we know the transaction is already started and has
5932  * enough credits) */
5933 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5934                                 const char *data, size_t len, loff_t off)
5935 {
5936         struct inode *inode = sb_dqopt(sb)->files[type];
5937         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5938         int err, offset = off & (sb->s_blocksize - 1);
5939         int retries = 0;
5940         struct buffer_head *bh;
5941         handle_t *handle = journal_current_handle();
5942
5943         if (EXT4_SB(sb)->s_journal && !handle) {
5944                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5945                         " cancelled because transaction is not started",
5946                         (unsigned long long)off, (unsigned long long)len);
5947                 return -EIO;
5948         }
5949         /*
5950          * Since we account only one data block in transaction credits,
5951          * then it is impossible to cross a block boundary.
5952          */
5953         if (sb->s_blocksize - offset < len) {
5954                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5955                         " cancelled because not block aligned",
5956                         (unsigned long long)off, (unsigned long long)len);
5957                 return -EIO;
5958         }
5959
5960         do {
5961                 bh = ext4_bread(handle, inode, blk,
5962                                 EXT4_GET_BLOCKS_CREATE |
5963                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
5964         } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
5965                  ext4_should_retry_alloc(inode->i_sb, &retries));
5966         if (IS_ERR(bh))
5967                 return PTR_ERR(bh);
5968         if (!bh)
5969                 goto out;
5970         BUFFER_TRACE(bh, "get write access");
5971         err = ext4_journal_get_write_access(handle, bh);
5972         if (err) {
5973                 brelse(bh);
5974                 return err;
5975         }
5976         lock_buffer(bh);
5977         memcpy(bh->b_data+offset, data, len);
5978         flush_dcache_page(bh->b_page);
5979         unlock_buffer(bh);
5980         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5981         brelse(bh);
5982 out:
5983         if (inode->i_size < off + len) {
5984                 i_size_write(inode, off + len);
5985                 EXT4_I(inode)->i_disksize = inode->i_size;
5986                 ext4_mark_inode_dirty(handle, inode);
5987         }
5988         return len;
5989 }
5990
5991 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid)
5992 {
5993         const struct quota_format_ops   *ops;
5994
5995         if (!sb_has_quota_loaded(sb, qid->type))
5996                 return -ESRCH;
5997         ops = sb_dqopt(sb)->ops[qid->type];
5998         if (!ops || !ops->get_next_id)
5999                 return -ENOSYS;
6000         return dquot_get_next_id(sb, qid);
6001 }
6002 #endif
6003
6004 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6005                        const char *dev_name, void *data)
6006 {
6007         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6008 }
6009
6010 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6011 static inline void register_as_ext2(void)
6012 {
6013         int err = register_filesystem(&ext2_fs_type);
6014         if (err)
6015                 printk(KERN_WARNING
6016                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6017 }
6018
6019 static inline void unregister_as_ext2(void)
6020 {
6021         unregister_filesystem(&ext2_fs_type);
6022 }
6023
6024 static inline int ext2_feature_set_ok(struct super_block *sb)
6025 {
6026         if (ext4_has_unknown_ext2_incompat_features(sb))
6027                 return 0;
6028         if (sb_rdonly(sb))
6029                 return 1;
6030         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6031                 return 0;
6032         return 1;
6033 }
6034 #else
6035 static inline void register_as_ext2(void) { }
6036 static inline void unregister_as_ext2(void) { }
6037 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6038 #endif
6039
6040 static inline void register_as_ext3(void)
6041 {
6042         int err = register_filesystem(&ext3_fs_type);
6043         if (err)
6044                 printk(KERN_WARNING
6045                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6046 }
6047
6048 static inline void unregister_as_ext3(void)
6049 {
6050         unregister_filesystem(&ext3_fs_type);
6051 }
6052
6053 static inline int ext3_feature_set_ok(struct super_block *sb)
6054 {
6055         if (ext4_has_unknown_ext3_incompat_features(sb))
6056                 return 0;
6057         if (!ext4_has_feature_journal(sb))
6058                 return 0;
6059         if (sb_rdonly(sb))
6060                 return 1;
6061         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6062                 return 0;
6063         return 1;
6064 }
6065
6066 static struct file_system_type ext4_fs_type = {
6067         .owner          = THIS_MODULE,
6068         .name           = "ext4",
6069         .mount          = ext4_mount,
6070         .kill_sb        = kill_block_super,
6071         .fs_flags       = FS_REQUIRES_DEV,
6072 };
6073 MODULE_ALIAS_FS("ext4");
6074
6075 /* Shared across all ext4 file systems */
6076 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6077
6078 static int __init ext4_init_fs(void)
6079 {
6080         int i, err;
6081
6082         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6083         ext4_li_info = NULL;
6084         mutex_init(&ext4_li_mtx);
6085
6086         /* Build-time check for flags consistency */
6087         ext4_check_flag_values();
6088
6089         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6090                 init_waitqueue_head(&ext4__ioend_wq[i]);
6091
6092         err = ext4_init_es();
6093         if (err)
6094                 return err;
6095
6096         err = ext4_init_pending();
6097         if (err)
6098                 goto out6;
6099
6100         err = ext4_init_pageio();
6101         if (err)
6102                 goto out5;
6103
6104         err = ext4_init_system_zone();
6105         if (err)
6106                 goto out4;
6107
6108         err = ext4_init_sysfs();
6109         if (err)
6110                 goto out3;
6111
6112         err = ext4_init_mballoc();
6113         if (err)
6114                 goto out2;
6115         err = init_inodecache();
6116         if (err)
6117                 goto out1;
6118         register_as_ext3();
6119         register_as_ext2();
6120         err = register_filesystem(&ext4_fs_type);
6121         if (err)
6122                 goto out;
6123
6124         return 0;
6125 out:
6126         unregister_as_ext2();
6127         unregister_as_ext3();
6128         destroy_inodecache();
6129 out1:
6130         ext4_exit_mballoc();
6131 out2:
6132         ext4_exit_sysfs();
6133 out3:
6134         ext4_exit_system_zone();
6135 out4:
6136         ext4_exit_pageio();
6137 out5:
6138         ext4_exit_pending();
6139 out6:
6140         ext4_exit_es();
6141
6142         return err;
6143 }
6144
6145 static void __exit ext4_exit_fs(void)
6146 {
6147         ext4_destroy_lazyinit_thread();
6148         unregister_as_ext2();
6149         unregister_as_ext3();
6150         unregister_filesystem(&ext4_fs_type);
6151         destroy_inodecache();
6152         ext4_exit_mballoc();
6153         ext4_exit_sysfs();
6154         ext4_exit_system_zone();
6155         ext4_exit_pageio();
6156         ext4_exit_es();
6157         ext4_exit_pending();
6158 }
6159
6160 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6161 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6162 MODULE_LICENSE("GPL");
6163 MODULE_SOFTDEP("pre: crc32c");
6164 module_init(ext4_init_fs)
6165 module_exit(ext4_exit_fs)