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 (ext4_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 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 208                                struct ext4_group_desc *bg)
 209 {
 210         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 211                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 212                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 213 }
 214
 215 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 216                                struct ext4_group_desc *bg)
 217 {
 218         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 219                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 220                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 221 }
 222
 223 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 224                               struct ext4_group_desc *bg)
 225 {
 226         return le32_to_cpu(bg->bg_inode_table_lo) |
 227                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 228                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 229 }
 230
 231 __u32 ext4_free_group_clusters(struct super_block *sb,
 232                                struct ext4_group_desc *bg)
 233 {
 234         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 235                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 236                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 237 }
 238
 239 __u32 ext4_free_inodes_count(struct super_block *sb,
 240                               struct ext4_group_desc *bg)
 241 {
 242         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 243                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 244                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 245 }
 246
 247 __u32 ext4_used_dirs_count(struct super_block *sb,
 248                               struct ext4_group_desc *bg)
 249 {
 250         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 251                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 252                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 253 }
 254
 255 __u32 ext4_itable_unused_count(struct super_block *sb,
 256                               struct ext4_group_desc *bg)
 257 {
 258         return le16_to_cpu(bg->bg_itable_unused_lo) |
 259                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 260                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 261 }
 262
 263 void ext4_block_bitmap_set(struct super_block *sb,
 264                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 265 {
 266         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 267         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 268                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 269 }
 270
 271 void ext4_inode_bitmap_set(struct super_block *sb,
 272                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 273 {
 274         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 275         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 276                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 277 }
 278
 279 void ext4_inode_table_set(struct super_block *sb,
 280                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 281 {
 282         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 283         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 284                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 285 }
 286
 287 void ext4_free_group_clusters_set(struct super_block *sb,
 288                                   struct ext4_group_desc *bg, __u32 count)
 289 {
 290         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 291         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 292                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 293 }
 294
 295 void ext4_free_inodes_set(struct super_block *sb,
 296                           struct ext4_group_desc *bg, __u32 count)
 297 {
 298         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 299         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 300                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 301 }
 302
 303 void ext4_used_dirs_set(struct super_block *sb,
 304                           struct ext4_group_desc *bg, __u32 count)
 305 {
 306         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 307         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 308                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 309 }
 310
 311 void ext4_itable_unused_set(struct super_block *sb,
 312                           struct ext4_group_desc *bg, __u32 count)
 313 {
 314         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 315         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 316                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 317 }
 318
 319 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi)
 320 {
 321         time64_t now = ktime_get_real_seconds();
 322
 323         now = clamp_val(now, 0, (1ull << 40) - 1);
 324
 325         *lo = cpu_to_le32(lower_32_bits(now));
 326         *hi = upper_32_bits(now);
 327 }
 328
 329 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 330 {
 331         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 332 }
 333 #define ext4_update_tstamp(es, tstamp) \
 334         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 335 #define ext4_get_tstamp(es, tstamp) \
 336         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 337
 338 static void __save_error_info(struct super_block *sb, const char *func,
 339                             unsigned int line)
 340 {
 341         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 342
 343         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 344         if (bdev_read_only(sb->s_bdev))
 345                 return;
 346         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 347         ext4_update_tstamp(es, s_last_error_time);
 348         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 349         es->s_last_error_line = cpu_to_le32(line);
 350         if (es->s_last_error_errcode == 0)
 351                 es->s_last_error_errcode = EXT4_ERR_EFSCORRUPTED;
 352         if (!es->s_first_error_time) {
 353                 es->s_first_error_time = es->s_last_error_time;
 354                 es->s_first_error_time_hi = es->s_last_error_time_hi;
 355                 strncpy(es->s_first_error_func, func,
 356                         sizeof(es->s_first_error_func));
 357                 es->s_first_error_line = cpu_to_le32(line);
 358                 es->s_first_error_ino = es->s_last_error_ino;
 359                 es->s_first_error_block = es->s_last_error_block;
 360                 es->s_first_error_errcode = es->s_last_error_errcode;
 361         }
 362         /*
 363          * Start the daily error reporting function if it hasn't been
 364          * started already
 365          */
 366         if (!es->s_error_count)
 367                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 368         le32_add_cpu(&es->s_error_count, 1);
 369 }
 370
 371 static void save_error_info(struct super_block *sb, const char *func,
 372                             unsigned int line)
 373 {
 374         __save_error_info(sb, func, line);
 375         ext4_commit_super(sb, 1);
 376 }
 377
 378 /*
 379  * The del_gendisk() function uninitializes the disk-specific data
 380  * structures, including the bdi structure, without telling anyone
 381  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 382  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 383  * This is a kludge to prevent these oops until we can put in a proper
 384  * hook in del_gendisk() to inform the VFS and file system layers.
 385  */
 386 static int block_device_ejected(struct super_block *sb)
 387 {
 388         struct inode *bd_inode = sb->s_bdev->bd_inode;
 389         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 390
 391         return bdi->dev == NULL;
 392 }
 393
 394 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 395 {
 396         struct super_block              *sb = journal->j_private;
 397         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 398         int                             error = is_journal_aborted(journal);
 399         struct ext4_journal_cb_entry    *jce;
 400
 401         BUG_ON(txn->t_state == T_FINISHED);
 402
 403         ext4_process_freed_data(sb, txn->t_tid);
 404
 405         spin_lock(&sbi->s_md_lock);
 406         while (!list_empty(&txn->t_private_list)) {
 407                 jce = list_entry(txn->t_private_list.next,
 408                                  struct ext4_journal_cb_entry, jce_list);
 409                 list_del_init(&jce->jce_list);
 410                 spin_unlock(&sbi->s_md_lock);
 411                 jce->jce_func(sb, jce, error);
 412                 spin_lock(&sbi->s_md_lock);
 413         }
 414         spin_unlock(&sbi->s_md_lock);
 415 }
 416
 417 static bool system_going_down(void)
 418 {
 419         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 420                 || system_state == SYSTEM_RESTART;
 421 }
 422
 423 /* Deal with the reporting of failure conditions on a filesystem such as
 424  * inconsistencies detected or read IO failures.
 425  *
 426  * On ext2, we can store the error state of the filesystem in the
 427  * superblock.  That is not possible on ext4, because we may have other
 428  * write ordering constraints on the superblock which prevent us from
 429  * writing it out straight away; and given that the journal is about to
 430  * be aborted, we can't rely on the current, or future, transactions to
 431  * write out the superblock safely.
 432  *
 433  * We'll just use the jbd2_journal_abort() error code to record an error in
 434  * the journal instead.  On recovery, the journal will complain about
 435  * that error until we've noted it down and cleared it.
 436  */
 437
 438 static void ext4_handle_error(struct super_block *sb)
 439 {
 440         if (test_opt(sb, WARN_ON_ERROR))
 441                 WARN_ON_ONCE(1);
 442
 443         if (sb_rdonly(sb))
 444                 return;
 445
 446         if (!test_opt(sb, ERRORS_CONT)) {
 447                 journal_t *journal = EXT4_SB(sb)->s_journal;
 448
 449                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 450                 if (journal)
 451                         jbd2_journal_abort(journal, -EIO);
 452         }
 453         /*
 454          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 455          * could panic during 'reboot -f' as the underlying device got already
 456          * disabled.
 457          */
 458         if (test_opt(sb, ERRORS_RO) || system_going_down()) {
 459                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 460                 /*
 461                  * Make sure updated value of ->s_mount_flags will be visible
 462                  * before ->s_flags update
 463                  */
 464                 smp_wmb();
 465                 sb->s_flags |= SB_RDONLY;
 466         } else if (test_opt(sb, ERRORS_PANIC)) {
 467                 if (EXT4_SB(sb)->s_journal &&
 468                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 469                         return;
 470                 panic("EXT4-fs (device %s): panic forced after error\n",
 471                         sb->s_id);
 472         }
 473 }
 474
 475 #define ext4_error_ratelimit(sb)                                        \
 476                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 477                              "EXT4-fs error")
 478
 479 void __ext4_error(struct super_block *sb, const char *function,
 480                   unsigned int line, const char *fmt, ...)
 481 {
 482         struct va_format vaf;
 483         va_list args;
 484
 485         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 486                 return;
 487
 488         trace_ext4_error(sb, function, line);
 489         if (ext4_error_ratelimit(sb)) {
 490                 va_start(args, fmt);
 491                 vaf.fmt = fmt;
 492                 vaf.va = &args;
 493                 printk(KERN_CRIT
 494                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 495                        sb->s_id, function, line, current->comm, &vaf);
 496                 va_end(args);
 497         }
 498         save_error_info(sb, function, line);
 499         ext4_handle_error(sb);
 500 }
 501
 502 void __ext4_error_inode(struct inode *inode, const char *function,
 503                         unsigned int line, ext4_fsblk_t block,
 504                         const char *fmt, ...)
 505 {
 506         va_list args;
 507         struct va_format vaf;
 508         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 509
 510         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 511                 return;
 512
 513         trace_ext4_error(inode->i_sb, function, line);
 514         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 515         es->s_last_error_block = cpu_to_le64(block);
 516         if (ext4_error_ratelimit(inode->i_sb)) {
 517                 va_start(args, fmt);
 518                 vaf.fmt = fmt;
 519                 vaf.va = &args;
 520                 if (block)
 521                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 522                                "inode #%lu: block %llu: comm %s: %pV\n",
 523                                inode->i_sb->s_id, function, line, inode->i_ino,
 524                                block, current->comm, &vaf);
 525                 else
 526                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 527                                "inode #%lu: comm %s: %pV\n",
 528                                inode->i_sb->s_id, function, line, inode->i_ino,
 529                                current->comm, &vaf);
 530                 va_end(args);
 531         }
 532         save_error_info(inode->i_sb, function, line);
 533         ext4_handle_error(inode->i_sb);
 534 }
 535
 536 void __ext4_error_file(struct file *file, const char *function,
 537                        unsigned int line, ext4_fsblk_t block,
 538                        const char *fmt, ...)
 539 {
 540         va_list args;
 541         struct va_format vaf;
 542         struct ext4_super_block *es;
 543         struct inode *inode = file_inode(file);
 544         char pathname[80], *path;
 545
 546         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 547                 return;
 548
 549         trace_ext4_error(inode->i_sb, function, line);
 550         es = EXT4_SB(inode->i_sb)->s_es;
 551         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 552         if (ext4_error_ratelimit(inode->i_sb)) {
 553                 path = file_path(file, pathname, sizeof(pathname));
 554                 if (IS_ERR(path))
 555                         path = "(unknown)";
 556                 va_start(args, fmt);
 557                 vaf.fmt = fmt;
 558                 vaf.va = &args;
 559                 if (block)
 560                         printk(KERN_CRIT
 561                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 562                                "block %llu: comm %s: path %s: %pV\n",
 563                                inode->i_sb->s_id, function, line, inode->i_ino,
 564                                block, current->comm, path, &vaf);
 565                 else
 566                         printk(KERN_CRIT
 567                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 568                                "comm %s: path %s: %pV\n",
 569                                inode->i_sb->s_id, function, line, inode->i_ino,
 570                                current->comm, path, &vaf);
 571                 va_end(args);
 572         }
 573         save_error_info(inode->i_sb, function, line);
 574         ext4_handle_error(inode->i_sb);
 575 }
 576
 577 const char *ext4_decode_error(struct super_block *sb, int errno,
 578                               char nbuf[16])
 579 {
 580         char *errstr = NULL;
 581
 582         switch (errno) {
 583         case -EFSCORRUPTED:
 584                 errstr = "Corrupt filesystem";
 585                 break;
 586         case -EFSBADCRC:
 587                 errstr = "Filesystem failed CRC";
 588                 break;
 589         case -EIO:
 590                 errstr = "IO failure";
 591                 break;
 592         case -ENOMEM:
 593                 errstr = "Out of memory";
 594                 break;
 595         case -EROFS:
 596                 if (!sb || (EXT4_SB(sb)->s_journal &&
 597                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 598                         errstr = "Journal has aborted";
 599                 else
 600                         errstr = "Readonly filesystem";
 601                 break;
 602         default:
 603                 /* If the caller passed in an extra buffer for unknown
 604                  * errors, textualise them now.  Else we just return
 605                  * NULL. */
 606                 if (nbuf) {
 607                         /* Check for truncated error codes... */
 608                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 609                                 errstr = nbuf;
 610                 }
 611                 break;
 612         }
 613
 614         return errstr;
 615 }
 616
 617 void ext4_set_errno(struct super_block *sb, int err)
 618 {
 619         if (err < 0)
 620                 err = -err;
 621
 622         switch (err) {
 623         case EIO:
 624                 err = EXT4_ERR_EIO;
 625                 break;
 626         case ENOMEM:
 627                 err = EXT4_ERR_ENOMEM;
 628                 break;
 629         case EFSBADCRC:
 630                 err = EXT4_ERR_EFSBADCRC;
 631                 break;
 632         case EFSCORRUPTED:
 633                 err = EXT4_ERR_EFSCORRUPTED;
 634                 break;
 635         case ENOSPC:
 636                 err = EXT4_ERR_ENOSPC;
 637                 break;
 638         case ENOKEY:
 639                 err = EXT4_ERR_ENOKEY;
 640                 break;
 641         case EROFS:
 642                 err = EXT4_ERR_EROFS;
 643                 break;
 644         case EFBIG:
 645                 err = EXT4_ERR_EFBIG;
 646                 break;
 647         case EEXIST:
 648                 err = EXT4_ERR_EEXIST;
 649                 break;
 650         case ERANGE:
 651                 err = EXT4_ERR_ERANGE;
 652                 break;
 653         case EOVERFLOW:
 654                 err = EXT4_ERR_EOVERFLOW;
 655                 break;
 656         case EBUSY:
 657                 err = EXT4_ERR_EBUSY;
 658                 break;
 659         case ENOTDIR:
 660                 err = EXT4_ERR_ENOTDIR;
 661                 break;
 662         case ENOTEMPTY:
 663                 err = EXT4_ERR_ENOTEMPTY;
 664                 break;
 665         case ESHUTDOWN:
 666                 err = EXT4_ERR_ESHUTDOWN;
 667                 break;
 668         case EFAULT:
 669                 err = EXT4_ERR_EFAULT;
 670                 break;
 671         default:
 672                 err = EXT4_ERR_UNKNOWN;
 673         }
 674         EXT4_SB(sb)->s_es->s_last_error_errcode = err;
 675 }
 676
 677 /* __ext4_std_error decodes expected errors from journaling functions
 678  * automatically and invokes the appropriate error response.  */
 679
 680 void __ext4_std_error(struct super_block *sb, const char *function,
 681                       unsigned int line, int errno)
 682 {
 683         char nbuf[16];
 684         const char *errstr;
 685
 686         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 687                 return;
 688
 689         /* Special case: if the error is EROFS, and we're not already
 690          * inside a transaction, then there's really no point in logging
 691          * an error. */
 692         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 693                 return;
 694
 695         if (ext4_error_ratelimit(sb)) {
 696                 errstr = ext4_decode_error(sb, errno, nbuf);
 697                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 698                        sb->s_id, function, line, errstr);
 699         }
 700
 701         ext4_set_errno(sb, -errno);
 702         save_error_info(sb, function, line);
 703         ext4_handle_error(sb);
 704 }
 705
 706 /*
 707  * ext4_abort is a much stronger failure handler than ext4_error.  The
 708  * abort function may be used to deal with unrecoverable failures such
 709  * as journal IO errors or ENOMEM at a critical moment in log management.
 710  *
 711  * We unconditionally force the filesystem into an ABORT|READONLY state,
 712  * unless the error response on the fs has been set to panic in which
 713  * case we take the easy way out and panic immediately.
 714  */
 715
 716 void __ext4_abort(struct super_block *sb, const char *function,
 717                 unsigned int line, const char *fmt, ...)
 718 {
 719         struct va_format vaf;
 720         va_list args;
 721
 722         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 723                 return;
 724
 725         save_error_info(sb, function, line);
 726         va_start(args, fmt);
 727         vaf.fmt = fmt;
 728         vaf.va = &args;
 729         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 730                sb->s_id, function, line, &vaf);
 731         va_end(args);
 732
 733         if (sb_rdonly(sb) == 0) {
 734                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 735                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 736                 /*
 737                  * Make sure updated value of ->s_mount_flags will be visible
 738                  * before ->s_flags update
 739                  */
 740                 smp_wmb();
 741                 sb->s_flags |= SB_RDONLY;
 742                 if (EXT4_SB(sb)->s_journal)
 743                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 744                 save_error_info(sb, function, line);
 745         }
 746         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
 747                 if (EXT4_SB(sb)->s_journal &&
 748                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 749                         return;
 750                 panic("EXT4-fs panic from previous error\n");
 751         }
 752 }
 753
 754 void __ext4_msg(struct super_block *sb,
 755                 const char *prefix, const char *fmt, ...)
 756 {
 757         struct va_format vaf;
 758         va_list args;
 759
 760         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 761                 return;
 762
 763         va_start(args, fmt);
 764         vaf.fmt = fmt;
 765         vaf.va = &args;
 766         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 767         va_end(args);
 768 }
 769
 770 #define ext4_warning_ratelimit(sb)                                      \
 771                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 772                              "EXT4-fs warning")
 773
 774 void __ext4_warning(struct super_block *sb, const char *function,
 775                     unsigned int line, const char *fmt, ...)
 776 {
 777         struct va_format vaf;
 778         va_list args;
 779
 780         if (!ext4_warning_ratelimit(sb))
 781                 return;
 782
 783         va_start(args, fmt);
 784         vaf.fmt = fmt;
 785         vaf.va = &args;
 786         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 787                sb->s_id, function, line, &vaf);
 788         va_end(args);
 789 }
 790
 791 void __ext4_warning_inode(const struct inode *inode, const char *function,
 792                           unsigned int line, const char *fmt, ...)
 793 {
 794         struct va_format vaf;
 795         va_list args;
 796
 797         if (!ext4_warning_ratelimit(inode->i_sb))
 798                 return;
 799
 800         va_start(args, fmt);
 801         vaf.fmt = fmt;
 802         vaf.va = &args;
 803         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 804                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 805                function, line, inode->i_ino, current->comm, &vaf);
 806         va_end(args);
 807 }
 808
 809 void __ext4_grp_locked_error(const char *function, unsigned int line,
 810                              struct super_block *sb, ext4_group_t grp,
 811                              unsigned long ino, ext4_fsblk_t block,
 812                              const char *fmt, ...)
 813 __releases(bitlock)
 814 __acquires(bitlock)
 815 {
 816         struct va_format vaf;
 817         va_list args;
 818         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 819
 820         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 821                 return;
 822
 823         trace_ext4_error(sb, function, line);
 824         es->s_last_error_ino = cpu_to_le32(ino);
 825         es->s_last_error_block = cpu_to_le64(block);
 826         __save_error_info(sb, function, line);
 827
 828         if (ext4_error_ratelimit(sb)) {
 829                 va_start(args, fmt);
 830                 vaf.fmt = fmt;
 831                 vaf.va = &args;
 832                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 833                        sb->s_id, function, line, grp);
 834                 if (ino)
 835                         printk(KERN_CONT "inode %lu: ", ino);
 836                 if (block)
 837                         printk(KERN_CONT "block %llu:",
 838                                (unsigned long long) block);
 839                 printk(KERN_CONT "%pV\n", &vaf);
 840                 va_end(args);
 841         }
 842
 843         if (test_opt(sb, WARN_ON_ERROR))
 844                 WARN_ON_ONCE(1);
 845
 846         if (test_opt(sb, ERRORS_CONT)) {
 847                 ext4_commit_super(sb, 0);
 848                 return;
 849         }
 850
 851         ext4_unlock_group(sb, grp);
 852         ext4_commit_super(sb, 1);
 853         ext4_handle_error(sb);
 854         /*
 855          * We only get here in the ERRORS_RO case; relocking the group
 856          * may be dangerous, but nothing bad will happen since the
 857          * filesystem will have already been marked read/only and the
 858          * journal has been aborted.  We return 1 as a hint to callers
 859          * who might what to use the return value from
 860          * ext4_grp_locked_error() to distinguish between the
 861          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 862          * aggressively from the ext4 function in question, with a
 863          * more appropriate error code.
 864          */
 865         ext4_lock_group(sb, grp);
 866         return;
 867 }
 868
 869 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
 870                                      ext4_group_t group,
 871                                      unsigned int flags)
 872 {
 873         struct ext4_sb_info *sbi = EXT4_SB(sb);
 874         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
 875         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
 876         int ret;
 877
 878         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
 879                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
 880                                             &grp->bb_state);
 881                 if (!ret)
 882                         percpu_counter_sub(&sbi->s_freeclusters_counter,
 883                                            grp->bb_free);
 884         }
 885
 886         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
 887                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
 888                                             &grp->bb_state);
 889                 if (!ret && gdp) {
 890                         int count;
 891
 892                         count = ext4_free_inodes_count(sb, gdp);
 893                         percpu_counter_sub(&sbi->s_freeinodes_counter,
 894                                            count);
 895                 }
 896         }
 897 }
 898
 899 void ext4_update_dynamic_rev(struct super_block *sb)
 900 {
 901         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 902
 903         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 904                 return;
 905
 906         ext4_warning(sb,
 907                      "updating to rev %d because of new feature flag, "
 908                      "running e2fsck is recommended",
 909                      EXT4_DYNAMIC_REV);
 910
 911         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 912         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 913         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 914         /* leave es->s_feature_*compat flags alone */
 915         /* es->s_uuid will be set by e2fsck if empty */
 916
 917         /*
 918          * The rest of the superblock fields should be zero, and if not it
 919          * means they are likely already in use, so leave them alone.  We
 920          * can leave it up to e2fsck to clean up any inconsistencies there.
 921          */
 922 }
 923
 924 /*
 925  * Open the external journal device
 926  */
 927 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 928 {
 929         struct block_device *bdev;
 930         char b[BDEVNAME_SIZE];
 931
 932         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 933         if (IS_ERR(bdev))
 934                 goto fail;
 935         return bdev;
 936
 937 fail:
 938         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 939                         __bdevname(dev, b), PTR_ERR(bdev));
 940         return NULL;
 941 }
 942
 943 /*
 944  * Release the journal device
 945  */
 946 static void ext4_blkdev_put(struct block_device *bdev)
 947 {
 948         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 949 }
 950
 951 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 952 {
 953         struct block_device *bdev;
 954         bdev = sbi->journal_bdev;
 955         if (bdev) {
 956                 ext4_blkdev_put(bdev);
 957                 sbi->journal_bdev = NULL;
 958         }
 959 }
 960
 961 static inline struct inode *orphan_list_entry(struct list_head *l)
 962 {
 963         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 964 }
 965
 966 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 967 {
 968         struct list_head *l;
 969
 970         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 971                  le32_to_cpu(sbi->s_es->s_last_orphan));
 972
 973         printk(KERN_ERR "sb_info orphan list:\n");
 974         list_for_each(l, &sbi->s_orphan) {
 975                 struct inode *inode = orphan_list_entry(l);
 976                 printk(KERN_ERR "  "
 977                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 978                        inode->i_sb->s_id, inode->i_ino, inode,
 979                        inode->i_mode, inode->i_nlink,
 980                        NEXT_ORPHAN(inode));
 981         }
 982 }
 983
 984 #ifdef CONFIG_QUOTA
 985 static int ext4_quota_off(struct super_block *sb, int type);
 986
 987 static inline void ext4_quota_off_umount(struct super_block *sb)
 988 {
 989         int type;
 990
 991         /* Use our quota_off function to clear inode flags etc. */
 992         for (type = 0; type < EXT4_MAXQUOTAS; type++)
 993                 ext4_quota_off(sb, type);
 994 }
 995
 996 /*
 997  * This is a helper function which is used in the mount/remount
 998  * codepaths (which holds s_umount) to fetch the quota file name.
 999  */
1000 static inline char *get_qf_name(struct super_block *sb,
1001                                 struct ext4_sb_info *sbi,
1002                                 int type)
1003 {
1004         return rcu_dereference_protected(sbi->s_qf_names[type],
1005                                          lockdep_is_held(&sb->s_umount));
1006 }
1007 #else
1008 static inline void ext4_quota_off_umount(struct super_block *sb)
1009 {
1010 }
1011 #endif
1012
1013 static void ext4_put_super(struct super_block *sb)
1014 {
1015         struct ext4_sb_info *sbi = EXT4_SB(sb);
1016         struct ext4_super_block *es = sbi->s_es;
1017         int aborted = 0;
1018         int i, err;
1019
1020         ext4_unregister_li_request(sb);
1021         ext4_quota_off_umount(sb);
1022
1023         destroy_workqueue(sbi->rsv_conversion_wq);
1024
1025         if (sbi->s_journal) {
1026                 aborted = is_journal_aborted(sbi->s_journal);
1027                 err = jbd2_journal_destroy(sbi->s_journal);
1028                 sbi->s_journal = NULL;
1029                 if ((err < 0) && !aborted) {
1030                         ext4_set_errno(sb, -err);
1031                         ext4_abort(sb, "Couldn't clean up the journal");
1032                 }
1033         }
1034
1035         ext4_unregister_sysfs(sb);
1036         ext4_es_unregister_shrinker(sbi);
1037         del_timer_sync(&sbi->s_err_report);
1038         ext4_release_system_zone(sb);
1039         ext4_mb_release(sb);
1040         ext4_ext_release(sb);
1041
1042         if (!sb_rdonly(sb) && !aborted) {
1043                 ext4_clear_feature_journal_needs_recovery(sb);
1044                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1045         }
1046         if (!sb_rdonly(sb))
1047                 ext4_commit_super(sb, 1);
1048
1049         for (i = 0; i < sbi->s_gdb_count; i++)
1050                 brelse(sbi->s_group_desc[i]);
1051         kvfree(sbi->s_group_desc);
1052         kvfree(sbi->s_flex_groups);
1053         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1054         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1055         percpu_counter_destroy(&sbi->s_dirs_counter);
1056         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1057         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
1058 #ifdef CONFIG_QUOTA
1059         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1060                 kfree(get_qf_name(sb, sbi, i));
1061 #endif
1062
1063         /* Debugging code just in case the in-memory inode orphan list
1064          * isn't empty.  The on-disk one can be non-empty if we've
1065          * detected an error and taken the fs readonly, but the
1066          * in-memory list had better be clean by this point. */
1067         if (!list_empty(&sbi->s_orphan))
1068                 dump_orphan_list(sb, sbi);
1069         J_ASSERT(list_empty(&sbi->s_orphan));
1070
1071         sync_blockdev(sb->s_bdev);
1072         invalidate_bdev(sb->s_bdev);
1073         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
1074                 /*
1075                  * Invalidate the journal device's buffers.  We don't want them
1076                  * floating about in memory - the physical journal device may
1077                  * hotswapped, and it breaks the `ro-after' testing code.
1078                  */
1079                 sync_blockdev(sbi->journal_bdev);
1080                 invalidate_bdev(sbi->journal_bdev);
1081                 ext4_blkdev_remove(sbi);
1082         }
1083
1084         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1085         sbi->s_ea_inode_cache = NULL;
1086
1087         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1088         sbi->s_ea_block_cache = NULL;
1089
1090         if (sbi->s_mmp_tsk)
1091                 kthread_stop(sbi->s_mmp_tsk);
1092         brelse(sbi->s_sbh);
1093         sb->s_fs_info = NULL;
1094         /*
1095          * Now that we are completely done shutting down the
1096          * superblock, we need to actually destroy the kobject.
1097          */
1098         kobject_put(&sbi->s_kobj);
1099         wait_for_completion(&sbi->s_kobj_unregister);
1100         if (sbi->s_chksum_driver)
1101                 crypto_free_shash(sbi->s_chksum_driver);
1102         kfree(sbi->s_blockgroup_lock);
1103         fs_put_dax(sbi->s_daxdev);
1104 #ifdef CONFIG_UNICODE
1105         utf8_unload(sbi->s_encoding);
1106 #endif
1107         kfree(sbi);
1108 }
1109
1110 static struct kmem_cache *ext4_inode_cachep;
1111
1112 /*
1113  * Called inside transaction, so use GFP_NOFS
1114  */
1115 static struct inode *ext4_alloc_inode(struct super_block *sb)
1116 {
1117         struct ext4_inode_info *ei;
1118
1119         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1120         if (!ei)
1121                 return NULL;
1122
1123         inode_set_iversion(&ei->vfs_inode, 1);
1124         spin_lock_init(&ei->i_raw_lock);
1125         INIT_LIST_HEAD(&ei->i_prealloc_list);
1126         spin_lock_init(&ei->i_prealloc_lock);
1127         ext4_es_init_tree(&ei->i_es_tree);
1128         rwlock_init(&ei->i_es_lock);
1129         INIT_LIST_HEAD(&ei->i_es_list);
1130         ei->i_es_all_nr = 0;
1131         ei->i_es_shk_nr = 0;
1132         ei->i_es_shrink_lblk = 0;
1133         ei->i_reserved_data_blocks = 0;
1134         spin_lock_init(&(ei->i_block_reservation_lock));
1135         ext4_init_pending_tree(&ei->i_pending_tree);
1136 #ifdef CONFIG_QUOTA
1137         ei->i_reserved_quota = 0;
1138         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1139 #endif
1140         ei->jinode = NULL;
1141         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1142         spin_lock_init(&ei->i_completed_io_lock);
1143         ei->i_sync_tid = 0;
1144         ei->i_datasync_tid = 0;
1145         atomic_set(&ei->i_unwritten, 0);
1146         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1147         return &ei->vfs_inode;
1148 }
1149
1150 static int ext4_drop_inode(struct inode *inode)
1151 {
1152         int drop = generic_drop_inode(inode);
1153
1154         if (!drop)
1155                 drop = fscrypt_drop_inode(inode);
1156
1157         trace_ext4_drop_inode(inode, drop);
1158         return drop;
1159 }
1160
1161 static void ext4_free_in_core_inode(struct inode *inode)
1162 {
1163         fscrypt_free_inode(inode);
1164         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1165 }
1166
1167 static void ext4_destroy_inode(struct inode *inode)
1168 {
1169         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1170                 ext4_msg(inode->i_sb, KERN_ERR,
1171                          "Inode %lu (%p): orphan list check failed!",
1172                          inode->i_ino, EXT4_I(inode));
1173                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1174                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1175                                 true);
1176                 dump_stack();
1177         }
1178 }
1179
1180 static void init_once(void *foo)
1181 {
1182         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1183
1184         INIT_LIST_HEAD(&ei->i_orphan);
1185         init_rwsem(&ei->xattr_sem);
1186         init_rwsem(&ei->i_data_sem);
1187         init_rwsem(&ei->i_mmap_sem);
1188         inode_init_once(&ei->vfs_inode);
1189 }
1190
1191 static int __init init_inodecache(void)
1192 {
1193         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1194                                 sizeof(struct ext4_inode_info), 0,
1195                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1196                                         SLAB_ACCOUNT),
1197                                 offsetof(struct ext4_inode_info, i_data),
1198                                 sizeof_field(struct ext4_inode_info, i_data),
1199                                 init_once);
1200         if (ext4_inode_cachep == NULL)
1201                 return -ENOMEM;
1202         return 0;
1203 }
1204
1205 static void destroy_inodecache(void)
1206 {
1207         /*
1208          * Make sure all delayed rcu free inodes are flushed before we
1209          * destroy cache.
1210          */
1211         rcu_barrier();
1212         kmem_cache_destroy(ext4_inode_cachep);
1213 }
1214
1215 void ext4_clear_inode(struct inode *inode)
1216 {
1217         invalidate_inode_buffers(inode);
1218         clear_inode(inode);
1219         ext4_discard_preallocations(inode);
1220         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1221         dquot_drop(inode);
1222         if (EXT4_I(inode)->jinode) {
1223                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1224                                                EXT4_I(inode)->jinode);
1225                 jbd2_free_inode(EXT4_I(inode)->jinode);
1226                 EXT4_I(inode)->jinode = NULL;
1227         }
1228         fscrypt_put_encryption_info(inode);
1229         fsverity_cleanup_inode(inode);
1230 }
1231
1232 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1233                                         u64 ino, u32 generation)
1234 {
1235         struct inode *inode;
1236
1237         /*
1238          * Currently we don't know the generation for parent directory, so
1239          * a generation of 0 means "accept any"
1240          */
1241         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1242         if (IS_ERR(inode))
1243                 return ERR_CAST(inode);
1244         if (generation && inode->i_generation != generation) {
1245                 iput(inode);
1246                 return ERR_PTR(-ESTALE);
1247         }
1248
1249         return inode;
1250 }
1251
1252 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1253                                         int fh_len, int fh_type)
1254 {
1255         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1256                                     ext4_nfs_get_inode);
1257 }
1258
1259 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1260                                         int fh_len, int fh_type)
1261 {
1262         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1263                                     ext4_nfs_get_inode);
1264 }
1265
1266 static int ext4_nfs_commit_metadata(struct inode *inode)
1267 {
1268         struct writeback_control wbc = {
1269                 .sync_mode = WB_SYNC_ALL
1270         };
1271
1272         trace_ext4_nfs_commit_metadata(inode);
1273         return ext4_write_inode(inode, &wbc);
1274 }
1275
1276 /*
1277  * Try to release metadata pages (indirect blocks, directories) which are
1278  * mapped via the block device.  Since these pages could have journal heads
1279  * which would prevent try_to_free_buffers() from freeing them, we must use
1280  * jbd2 layer's try_to_free_buffers() function to release them.
1281  */
1282 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1283                                  gfp_t wait)
1284 {
1285         journal_t *journal = EXT4_SB(sb)->s_journal;
1286
1287         WARN_ON(PageChecked(page));
1288         if (!page_has_buffers(page))
1289                 return 0;
1290         if (journal)
1291                 return jbd2_journal_try_to_free_buffers(journal, page,
1292                                                 wait & ~__GFP_DIRECT_RECLAIM);
1293         return try_to_free_buffers(page);
1294 }
1295
1296 #ifdef CONFIG_FS_ENCRYPTION
1297 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1298 {
1299         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1300                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1301 }
1302
1303 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1304                                                         void *fs_data)
1305 {
1306         handle_t *handle = fs_data;
1307         int res, res2, credits, retries = 0;
1308
1309         /*
1310          * Encrypting the root directory is not allowed because e2fsck expects
1311          * lost+found to exist and be unencrypted, and encrypting the root
1312          * directory would imply encrypting the lost+found directory as well as
1313          * the filename "lost+found" itself.
1314          */
1315         if (inode->i_ino == EXT4_ROOT_INO)
1316                 return -EPERM;
1317
1318         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1319                 return -EINVAL;
1320
1321         res = ext4_convert_inline_data(inode);
1322         if (res)
1323                 return res;
1324
1325         /*
1326          * If a journal handle was specified, then the encryption context is
1327          * being set on a new inode via inheritance and is part of a larger
1328          * transaction to create the inode.  Otherwise the encryption context is
1329          * being set on an existing inode in its own transaction.  Only in the
1330          * latter case should the "retry on ENOSPC" logic be used.
1331          */
1332
1333         if (handle) {
1334                 res = ext4_xattr_set_handle(handle, inode,
1335                                             EXT4_XATTR_INDEX_ENCRYPTION,
1336                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1337                                             ctx, len, 0);
1338                 if (!res) {
1339                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1340                         ext4_clear_inode_state(inode,
1341                                         EXT4_STATE_MAY_INLINE_DATA);
1342                         /*
1343                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1344                          * S_DAX may be disabled
1345                          */
1346                         ext4_set_inode_flags(inode);
1347                 }
1348                 return res;
1349         }
1350
1351         res = dquot_initialize(inode);
1352         if (res)
1353                 return res;
1354 retry:
1355         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1356                                      &credits);
1357         if (res)
1358                 return res;
1359
1360         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1361         if (IS_ERR(handle))
1362                 return PTR_ERR(handle);
1363
1364         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1365                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1366                                     ctx, len, 0);
1367         if (!res) {
1368                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1369                 /*
1370                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1371                  * S_DAX may be disabled
1372                  */
1373                 ext4_set_inode_flags(inode);
1374                 res = ext4_mark_inode_dirty(handle, inode);
1375                 if (res)
1376                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1377         }
1378         res2 = ext4_journal_stop(handle);
1379
1380         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1381                 goto retry;
1382         if (!res)
1383                 res = res2;
1384         return res;
1385 }
1386
1387 static bool ext4_dummy_context(struct inode *inode)
1388 {
1389         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1390 }
1391
1392 static bool ext4_has_stable_inodes(struct super_block *sb)
1393 {
1394         return ext4_has_feature_stable_inodes(sb);
1395 }
1396
1397 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1398                                        int *ino_bits_ret, int *lblk_bits_ret)
1399 {
1400         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1401         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1402 }
1403
1404 static const struct fscrypt_operations ext4_cryptops = {
1405         .key_prefix             = "ext4:",
1406         .get_context            = ext4_get_context,
1407         .set_context            = ext4_set_context,
1408         .dummy_context          = ext4_dummy_context,
1409         .empty_dir              = ext4_empty_dir,
1410         .max_namelen            = EXT4_NAME_LEN,
1411         .has_stable_inodes      = ext4_has_stable_inodes,
1412         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1413 };
1414 #endif
1415
1416 #ifdef CONFIG_QUOTA
1417 static const char * const quotatypes[] = INITQFNAMES;
1418 #define QTYPE2NAME(t) (quotatypes[t])
1419
1420 static int ext4_write_dquot(struct dquot *dquot);
1421 static int ext4_acquire_dquot(struct dquot *dquot);
1422 static int ext4_release_dquot(struct dquot *dquot);
1423 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1424 static int ext4_write_info(struct super_block *sb, int type);
1425 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1426                          const struct path *path);
1427 static int ext4_quota_on_mount(struct super_block *sb, int type);
1428 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1429                                size_t len, loff_t off);
1430 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1431                                 const char *data, size_t len, loff_t off);
1432 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1433                              unsigned int flags);
1434 static int ext4_enable_quotas(struct super_block *sb);
1435
1436 static struct dquot **ext4_get_dquots(struct inode *inode)
1437 {
1438         return EXT4_I(inode)->i_dquot;
1439 }
1440
1441 static const struct dquot_operations ext4_quota_operations = {
1442         .get_reserved_space     = ext4_get_reserved_space,
1443         .write_dquot            = ext4_write_dquot,
1444         .acquire_dquot          = ext4_acquire_dquot,
1445         .release_dquot          = ext4_release_dquot,
1446         .mark_dirty             = ext4_mark_dquot_dirty,
1447         .write_info             = ext4_write_info,
1448         .alloc_dquot            = dquot_alloc,
1449         .destroy_dquot          = dquot_destroy,
1450         .get_projid             = ext4_get_projid,
1451         .get_inode_usage        = ext4_get_inode_usage,
1452         .get_next_id            = dquot_get_next_id,
1453 };
1454
1455 static const struct quotactl_ops ext4_qctl_operations = {
1456         .quota_on       = ext4_quota_on,
1457         .quota_off      = ext4_quota_off,
1458         .quota_sync     = dquot_quota_sync,
1459         .get_state      = dquot_get_state,
1460         .set_info       = dquot_set_dqinfo,
1461         .get_dqblk      = dquot_get_dqblk,
1462         .set_dqblk      = dquot_set_dqblk,
1463         .get_nextdqblk  = dquot_get_next_dqblk,
1464 };
1465 #endif
1466
1467 static const struct super_operations ext4_sops = {
1468         .alloc_inode    = ext4_alloc_inode,
1469         .free_inode     = ext4_free_in_core_inode,
1470         .destroy_inode  = ext4_destroy_inode,
1471         .write_inode    = ext4_write_inode,
1472         .dirty_inode    = ext4_dirty_inode,
1473         .drop_inode     = ext4_drop_inode,
1474         .evict_inode    = ext4_evict_inode,
1475         .put_super      = ext4_put_super,
1476         .sync_fs        = ext4_sync_fs,
1477         .freeze_fs      = ext4_freeze,
1478         .unfreeze_fs    = ext4_unfreeze,
1479         .statfs         = ext4_statfs,
1480         .remount_fs     = ext4_remount,
1481         .show_options   = ext4_show_options,
1482 #ifdef CONFIG_QUOTA
1483         .quota_read     = ext4_quota_read,
1484         .quota_write    = ext4_quota_write,
1485         .get_dquots     = ext4_get_dquots,
1486 #endif
1487         .bdev_try_to_free_page = bdev_try_to_free_page,
1488 };
1489
1490 static const struct export_operations ext4_export_ops = {
1491         .fh_to_dentry = ext4_fh_to_dentry,
1492         .fh_to_parent = ext4_fh_to_parent,
1493         .get_parent = ext4_get_parent,
1494         .commit_metadata = ext4_nfs_commit_metadata,
1495 };
1496
1497 enum {
1498         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1499         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1500         Opt_nouid32, Opt_debug, Opt_removed,
1501         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1502         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1503         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1504         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1505         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1506         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1507         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1508         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1509         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1510         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1511         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1512         Opt_nowarn_on_error, Opt_mblk_io_submit,
1513         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1514         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1515         Opt_inode_readahead_blks, Opt_journal_ioprio,
1516         Opt_dioread_nolock, Opt_dioread_lock,
1517         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1518         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1519 };
1520
1521 static const match_table_t tokens = {
1522         {Opt_bsd_df, "bsddf"},
1523         {Opt_minix_df, "minixdf"},
1524         {Opt_grpid, "grpid"},
1525         {Opt_grpid, "bsdgroups"},
1526         {Opt_nogrpid, "nogrpid"},
1527         {Opt_nogrpid, "sysvgroups"},
1528         {Opt_resgid, "resgid=%u"},
1529         {Opt_resuid, "resuid=%u"},
1530         {Opt_sb, "sb=%u"},
1531         {Opt_err_cont, "errors=continue"},
1532         {Opt_err_panic, "errors=panic"},
1533         {Opt_err_ro, "errors=remount-ro"},
1534         {Opt_nouid32, "nouid32"},
1535         {Opt_debug, "debug"},
1536         {Opt_removed, "oldalloc"},
1537         {Opt_removed, "orlov"},
1538         {Opt_user_xattr, "user_xattr"},
1539         {Opt_nouser_xattr, "nouser_xattr"},
1540         {Opt_acl, "acl"},
1541         {Opt_noacl, "noacl"},
1542         {Opt_noload, "norecovery"},
1543         {Opt_noload, "noload"},
1544         {Opt_removed, "nobh"},
1545         {Opt_removed, "bh"},
1546         {Opt_commit, "commit=%u"},
1547         {Opt_min_batch_time, "min_batch_time=%u"},
1548         {Opt_max_batch_time, "max_batch_time=%u"},
1549         {Opt_journal_dev, "journal_dev=%u"},
1550         {Opt_journal_path, "journal_path=%s"},
1551         {Opt_journal_checksum, "journal_checksum"},
1552         {Opt_nojournal_checksum, "nojournal_checksum"},
1553         {Opt_journal_async_commit, "journal_async_commit"},
1554         {Opt_abort, "abort"},
1555         {Opt_data_journal, "data=journal"},
1556         {Opt_data_ordered, "data=ordered"},
1557         {Opt_data_writeback, "data=writeback"},
1558         {Opt_data_err_abort, "data_err=abort"},
1559         {Opt_data_err_ignore, "data_err=ignore"},
1560         {Opt_offusrjquota, "usrjquota="},
1561         {Opt_usrjquota, "usrjquota=%s"},
1562         {Opt_offgrpjquota, "grpjquota="},
1563         {Opt_grpjquota, "grpjquota=%s"},
1564         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1565         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1566         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1567         {Opt_grpquota, "grpquota"},
1568         {Opt_noquota, "noquota"},
1569         {Opt_quota, "quota"},
1570         {Opt_usrquota, "usrquota"},
1571         {Opt_prjquota, "prjquota"},
1572         {Opt_barrier, "barrier=%u"},
1573         {Opt_barrier, "barrier"},
1574         {Opt_nobarrier, "nobarrier"},
1575         {Opt_i_version, "i_version"},
1576         {Opt_dax, "dax"},
1577         {Opt_stripe, "stripe=%u"},
1578         {Opt_delalloc, "delalloc"},
1579         {Opt_warn_on_error, "warn_on_error"},
1580         {Opt_nowarn_on_error, "nowarn_on_error"},
1581         {Opt_lazytime, "lazytime"},
1582         {Opt_nolazytime, "nolazytime"},
1583         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1584         {Opt_nodelalloc, "nodelalloc"},
1585         {Opt_removed, "mblk_io_submit"},
1586         {Opt_removed, "nomblk_io_submit"},
1587         {Opt_block_validity, "block_validity"},
1588         {Opt_noblock_validity, "noblock_validity"},
1589         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1590         {Opt_journal_ioprio, "journal_ioprio=%u"},
1591         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1592         {Opt_auto_da_alloc, "auto_da_alloc"},
1593         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1594         {Opt_dioread_nolock, "dioread_nolock"},
1595         {Opt_dioread_lock, "nodioread_nolock"},
1596         {Opt_dioread_lock, "dioread_lock"},
1597         {Opt_discard, "discard"},
1598         {Opt_nodiscard, "nodiscard"},
1599         {Opt_init_itable, "init_itable=%u"},
1600         {Opt_init_itable, "init_itable"},
1601         {Opt_noinit_itable, "noinit_itable"},
1602         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1603         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1604         {Opt_nombcache, "nombcache"},
1605         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1606         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1607         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1608         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1609         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1610         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1611         {Opt_err, NULL},
1612 };
1613
1614 static ext4_fsblk_t get_sb_block(void **data)
1615 {
1616         ext4_fsblk_t    sb_block;
1617         char            *options = (char *) *data;
1618
1619         if (!options || strncmp(options, "sb=", 3) != 0)
1620                 return 1;       /* Default location */
1621
1622         options += 3;
1623         /* TODO: use simple_strtoll with >32bit ext4 */
1624         sb_block = simple_strtoul(options, &options, 0);
1625         if (*options && *options != ',') {
1626                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1627                        (char *) *data);
1628                 return 1;
1629         }
1630         if (*options == ',')
1631                 options++;
1632         *data = (void *) options;
1633
1634         return sb_block;
1635 }
1636
1637 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1638 static const char deprecated_msg[] =
1639         "Mount option \"%s\" will be removed by %s\n"
1640         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1641
1642 #ifdef CONFIG_QUOTA
1643 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1644 {
1645         struct ext4_sb_info *sbi = EXT4_SB(sb);
1646         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1647         int ret = -1;
1648
1649         if (sb_any_quota_loaded(sb) && !old_qname) {
1650                 ext4_msg(sb, KERN_ERR,
1651                         "Cannot change journaled "
1652                         "quota options when quota turned on");
1653                 return -1;
1654         }
1655         if (ext4_has_feature_quota(sb)) {
1656                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1657                          "ignored when QUOTA feature is enabled");
1658                 return 1;
1659         }
1660         qname = match_strdup(args);
1661         if (!qname) {
1662                 ext4_msg(sb, KERN_ERR,
1663                         "Not enough memory for storing quotafile name");
1664                 return -1;
1665         }
1666         if (old_qname) {
1667                 if (strcmp(old_qname, qname) == 0)
1668                         ret = 1;
1669                 else
1670                         ext4_msg(sb, KERN_ERR,
1671                                  "%s quota file already specified",
1672                                  QTYPE2NAME(qtype));
1673                 goto errout;
1674         }
1675         if (strchr(qname, '/')) {
1676                 ext4_msg(sb, KERN_ERR,
1677                         "quotafile must be on filesystem root");
1678                 goto errout;
1679         }
1680         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1681         set_opt(sb, QUOTA);
1682         return 1;
1683 errout:
1684         kfree(qname);
1685         return ret;
1686 }
1687
1688 static int clear_qf_name(struct super_block *sb, int qtype)
1689 {
1690
1691         struct ext4_sb_info *sbi = EXT4_SB(sb);
1692         char *old_qname = get_qf_name(sb, sbi, qtype);
1693
1694         if (sb_any_quota_loaded(sb) && old_qname) {
1695                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1696                         " when quota turned on");
1697                 return -1;
1698         }
1699         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1700         synchronize_rcu();
1701         kfree(old_qname);
1702         return 1;
1703 }
1704 #endif
1705
1706 #define MOPT_SET        0x0001
1707 #define MOPT_CLEAR      0x0002
1708 #define MOPT_NOSUPPORT  0x0004
1709 #define MOPT_EXPLICIT   0x0008
1710 #define MOPT_CLEAR_ERR  0x0010
1711 #define MOPT_GTE0       0x0020
1712 #ifdef CONFIG_QUOTA
1713 #define MOPT_Q          0
1714 #define MOPT_QFMT       0x0040
1715 #else
1716 #define MOPT_Q          MOPT_NOSUPPORT
1717 #define MOPT_QFMT       MOPT_NOSUPPORT
1718 #endif
1719 #define MOPT_DATAJ      0x0080
1720 #define MOPT_NO_EXT2    0x0100
1721 #define MOPT_NO_EXT3    0x0200
1722 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1723 #define MOPT_STRING     0x0400
1724
1725 static const struct mount_opts {
1726         int     token;
1727         int     mount_opt;
1728         int     flags;
1729 } ext4_mount_opts[] = {
1730         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1731         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1732         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1733         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1734         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1735         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1736         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1737          MOPT_EXT4_ONLY | MOPT_SET},
1738         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1739          MOPT_EXT4_ONLY | MOPT_CLEAR},
1740         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1741         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1742         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1743          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1744         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1745          MOPT_EXT4_ONLY | MOPT_CLEAR},
1746         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1747         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1748         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1749          MOPT_EXT4_ONLY | MOPT_CLEAR},
1750         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1751          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1752         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1753                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1754          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1755         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1756         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1757         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1758         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1759         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1760          MOPT_NO_EXT2},
1761         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1762          MOPT_NO_EXT2},
1763         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1764         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1765         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1766         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1767         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1768         {Opt_commit, 0, MOPT_GTE0},
1769         {Opt_max_batch_time, 0, MOPT_GTE0},
1770         {Opt_min_batch_time, 0, MOPT_GTE0},
1771         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1772         {Opt_init_itable, 0, MOPT_GTE0},
1773         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1774         {Opt_stripe, 0, MOPT_GTE0},
1775         {Opt_resuid, 0, MOPT_GTE0},
1776         {Opt_resgid, 0, MOPT_GTE0},
1777         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1778         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1779         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1780         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1781         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1782         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1783          MOPT_NO_EXT2 | MOPT_DATAJ},
1784         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1785         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1786 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1787         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1788         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1789 #else
1790         {Opt_acl, 0, MOPT_NOSUPPORT},
1791         {Opt_noacl, 0, MOPT_NOSUPPORT},
1792 #endif
1793         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1794         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1795         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1796         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1797         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1798                                                         MOPT_SET | MOPT_Q},
1799         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1800                                                         MOPT_SET | MOPT_Q},
1801         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1802                                                         MOPT_SET | MOPT_Q},
1803         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1804                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1805                                                         MOPT_CLEAR | MOPT_Q},
1806         {Opt_usrjquota, 0, MOPT_Q},
1807         {Opt_grpjquota, 0, MOPT_Q},
1808         {Opt_offusrjquota, 0, MOPT_Q},
1809         {Opt_offgrpjquota, 0, MOPT_Q},
1810         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1811         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1812         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1813         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1814         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1815         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1816         {Opt_err, 0, 0}
1817 };
1818
1819 #ifdef CONFIG_UNICODE
1820 static const struct ext4_sb_encodings {
1821         __u16 magic;
1822         char *name;
1823         char *version;
1824 } ext4_sb_encoding_map[] = {
1825         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
1826 };
1827
1828 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
1829                                  const struct ext4_sb_encodings **encoding,
1830                                  __u16 *flags)
1831 {
1832         __u16 magic = le16_to_cpu(es->s_encoding);
1833         int i;
1834
1835         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1836                 if (magic == ext4_sb_encoding_map[i].magic)
1837                         break;
1838
1839         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
1840                 return -EINVAL;
1841
1842         *encoding = &ext4_sb_encoding_map[i];
1843         *flags = le16_to_cpu(es->s_encoding_flags);
1844
1845         return 0;
1846 }
1847 #endif
1848
1849 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1850                             substring_t *args, unsigned long *journal_devnum,
1851                             unsigned int *journal_ioprio, int is_remount)
1852 {
1853         struct ext4_sb_info *sbi = EXT4_SB(sb);
1854         const struct mount_opts *m;
1855         kuid_t uid;
1856         kgid_t gid;
1857         int arg = 0;
1858
1859 #ifdef CONFIG_QUOTA
1860         if (token == Opt_usrjquota)
1861                 return set_qf_name(sb, USRQUOTA, &args[0]);
1862         else if (token == Opt_grpjquota)
1863                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1864         else if (token == Opt_offusrjquota)
1865                 return clear_qf_name(sb, USRQUOTA);
1866         else if (token == Opt_offgrpjquota)
1867                 return clear_qf_name(sb, GRPQUOTA);
1868 #endif
1869         switch (token) {
1870         case Opt_noacl:
1871         case Opt_nouser_xattr:
1872                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1873                 break;
1874         case Opt_sb:
1875                 return 1;       /* handled by get_sb_block() */
1876         case Opt_removed:
1877                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1878                 return 1;
1879         case Opt_abort:
1880                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1881                 return 1;
1882         case Opt_i_version:
1883                 sb->s_flags |= SB_I_VERSION;
1884                 return 1;
1885         case Opt_lazytime:
1886                 sb->s_flags |= SB_LAZYTIME;
1887                 return 1;
1888         case Opt_nolazytime:
1889                 sb->s_flags &= ~SB_LAZYTIME;
1890                 return 1;
1891         }
1892
1893         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1894                 if (token == m->token)
1895                         break;
1896
1897         if (m->token == Opt_err) {
1898                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1899                          "or missing value", opt);
1900                 return -1;
1901         }
1902
1903         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1904                 ext4_msg(sb, KERN_ERR,
1905                          "Mount option \"%s\" incompatible with ext2", opt);
1906                 return -1;
1907         }
1908         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1909                 ext4_msg(sb, KERN_ERR,
1910                          "Mount option \"%s\" incompatible with ext3", opt);
1911                 return -1;
1912         }
1913
1914         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1915                 return -1;
1916         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1917                 return -1;
1918         if (m->flags & MOPT_EXPLICIT) {
1919                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1920                         set_opt2(sb, EXPLICIT_DELALLOC);
1921                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1922                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1923                 } else
1924                         return -1;
1925         }
1926         if (m->flags & MOPT_CLEAR_ERR)
1927                 clear_opt(sb, ERRORS_MASK);
1928         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1929                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1930                          "options when quota turned on");
1931                 return -1;
1932         }
1933
1934         if (m->flags & MOPT_NOSUPPORT) {
1935                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1936         } else if (token == Opt_commit) {
1937                 if (arg == 0)
1938                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1939                 else if (arg > INT_MAX / HZ) {
1940                         ext4_msg(sb, KERN_ERR,
1941                                  "Invalid commit interval %d, "
1942                                  "must be smaller than %d",
1943                                  arg, INT_MAX / HZ);
1944                         return -1;
1945                 }
1946                 sbi->s_commit_interval = HZ * arg;
1947         } else if (token == Opt_debug_want_extra_isize) {
1948                 if ((arg & 1) ||
1949                     (arg < 4) ||
1950                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
1951                         ext4_msg(sb, KERN_ERR,
1952                                  "Invalid want_extra_isize %d", arg);
1953                         return -1;
1954                 }
1955                 sbi->s_want_extra_isize = arg;
1956         } else if (token == Opt_max_batch_time) {
1957                 sbi->s_max_batch_time = arg;
1958         } else if (token == Opt_min_batch_time) {
1959                 sbi->s_min_batch_time = arg;
1960         } else if (token == Opt_inode_readahead_blks) {
1961                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1962                         ext4_msg(sb, KERN_ERR,
1963                                  "EXT4-fs: inode_readahead_blks must be "
1964                                  "0 or a power of 2 smaller than 2^31");
1965                         return -1;
1966                 }
1967                 sbi->s_inode_readahead_blks = arg;
1968         } else if (token == Opt_init_itable) {
1969                 set_opt(sb, INIT_INODE_TABLE);
1970                 if (!args->from)
1971                         arg = EXT4_DEF_LI_WAIT_MULT;
1972                 sbi->s_li_wait_mult = arg;
1973         } else if (token == Opt_max_dir_size_kb) {
1974                 sbi->s_max_dir_size_kb = arg;
1975         } else if (token == Opt_stripe) {
1976                 sbi->s_stripe = arg;
1977         } else if (token == Opt_resuid) {
1978                 uid = make_kuid(current_user_ns(), arg);
1979                 if (!uid_valid(uid)) {
1980                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1981                         return -1;
1982                 }
1983                 sbi->s_resuid = uid;
1984         } else if (token == Opt_resgid) {
1985                 gid = make_kgid(current_user_ns(), arg);
1986                 if (!gid_valid(gid)) {
1987                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1988                         return -1;
1989                 }
1990                 sbi->s_resgid = gid;
1991         } else if (token == Opt_journal_dev) {
1992                 if (is_remount) {
1993                         ext4_msg(sb, KERN_ERR,
1994                                  "Cannot specify journal on remount");
1995                         return -1;
1996                 }
1997                 *journal_devnum = arg;
1998         } else if (token == Opt_journal_path) {
1999                 char *journal_path;
2000                 struct inode *journal_inode;
2001                 struct path path;
2002                 int error;
2003
2004                 if (is_remount) {
2005                         ext4_msg(sb, KERN_ERR,
2006                                  "Cannot specify journal on remount");
2007                         return -1;
2008                 }
2009                 journal_path = match_strdup(&args[0]);
2010                 if (!journal_path) {
2011                         ext4_msg(sb, KERN_ERR, "error: could not dup "
2012                                 "journal device string");
2013                         return -1;
2014                 }
2015
2016                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2017                 if (error) {
2018                         ext4_msg(sb, KERN_ERR, "error: could not find "
2019                                 "journal device path: error %d", error);
2020                         kfree(journal_path);
2021                         return -1;
2022                 }
2023
2024                 journal_inode = d_inode(path.dentry);
2025                 if (!S_ISBLK(journal_inode->i_mode)) {
2026                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
2027                                 "is not a block device", journal_path);
2028                         path_put(&path);
2029                         kfree(journal_path);
2030                         return -1;
2031                 }
2032
2033                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
2034                 path_put(&path);
2035                 kfree(journal_path);
2036         } else if (token == Opt_journal_ioprio) {
2037                 if (arg > 7) {
2038                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2039                                  " (must be 0-7)");
2040                         return -1;
2041                 }
2042                 *journal_ioprio =
2043                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2044         } else if (token == Opt_test_dummy_encryption) {
2045 #ifdef CONFIG_FS_ENCRYPTION
2046                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
2047                 ext4_msg(sb, KERN_WARNING,
2048                          "Test dummy encryption mode enabled");
2049 #else
2050                 ext4_msg(sb, KERN_WARNING,
2051                          "Test dummy encryption mount option ignored");
2052 #endif
2053         } else if (m->flags & MOPT_DATAJ) {
2054                 if (is_remount) {
2055                         if (!sbi->s_journal)
2056                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2057                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2058                                 ext4_msg(sb, KERN_ERR,
2059                                          "Cannot change data mode on remount");
2060                                 return -1;
2061                         }
2062                 } else {
2063                         clear_opt(sb, DATA_FLAGS);
2064                         sbi->s_mount_opt |= m->mount_opt;
2065                 }
2066 #ifdef CONFIG_QUOTA
2067         } else if (m->flags & MOPT_QFMT) {
2068                 if (sb_any_quota_loaded(sb) &&
2069                     sbi->s_jquota_fmt != m->mount_opt) {
2070                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2071                                  "quota options when quota turned on");
2072                         return -1;
2073                 }
2074                 if (ext4_has_feature_quota(sb)) {
2075                         ext4_msg(sb, KERN_INFO,
2076                                  "Quota format mount options ignored "
2077                                  "when QUOTA feature is enabled");
2078                         return 1;
2079                 }
2080                 sbi->s_jquota_fmt = m->mount_opt;
2081 #endif
2082         } else if (token == Opt_dax) {
2083 #ifdef CONFIG_FS_DAX
2084                 ext4_msg(sb, KERN_WARNING,
2085                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2086                 sbi->s_mount_opt |= m->mount_opt;
2087 #else
2088                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2089                 return -1;
2090 #endif
2091         } else if (token == Opt_data_err_abort) {
2092                 sbi->s_mount_opt |= m->mount_opt;
2093         } else if (token == Opt_data_err_ignore) {
2094                 sbi->s_mount_opt &= ~m->mount_opt;
2095         } else {
2096                 if (!args->from)
2097                         arg = 1;
2098                 if (m->flags & MOPT_CLEAR)
2099                         arg = !arg;
2100                 else if (unlikely(!(m->flags & MOPT_SET))) {
2101                         ext4_msg(sb, KERN_WARNING,
2102                                  "buggy handling of option %s", opt);
2103                         WARN_ON(1);
2104                         return -1;
2105                 }
2106                 if (arg != 0)
2107                         sbi->s_mount_opt |= m->mount_opt;
2108                 else
2109                         sbi->s_mount_opt &= ~m->mount_opt;
2110         }
2111         return 1;
2112 }
2113
2114 static int parse_options(char *options, struct super_block *sb,
2115                          unsigned long *journal_devnum,
2116                          unsigned int *journal_ioprio,
2117                          int is_remount)
2118 {
2119         struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2120         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2121         substring_t args[MAX_OPT_ARGS];
2122         int token;
2123
2124         if (!options)
2125                 return 1;
2126
2127         while ((p = strsep(&options, ",")) != NULL) {
2128                 if (!*p)
2129                         continue;
2130                 /*
2131                  * Initialize args struct so we know whether arg was
2132                  * found; some options take optional arguments.
2133                  */
2134                 args[0].to = args[0].from = NULL;
2135                 token = match_token(p, tokens, args);
2136                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2137                                      journal_ioprio, is_remount) < 0)
2138                         return 0;
2139         }
2140 #ifdef CONFIG_QUOTA
2141         /*
2142          * We do the test below only for project quotas. 'usrquota' and
2143          * 'grpquota' mount options are allowed even without quota feature
2144          * to support legacy quotas in quota files.
2145          */
2146         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2147                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2148                          "Cannot enable project quota enforcement.");
2149                 return 0;
2150         }
2151         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2152         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2153         if (usr_qf_name || grp_qf_name) {
2154                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2155                         clear_opt(sb, USRQUOTA);
2156
2157                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2158                         clear_opt(sb, GRPQUOTA);
2159
2160                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2161                         ext4_msg(sb, KERN_ERR, "old and new quota "
2162                                         "format mixing");
2163                         return 0;
2164                 }
2165
2166                 if (!sbi->s_jquota_fmt) {
2167                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2168                                         "not specified");
2169                         return 0;
2170                 }
2171         }
2172 #endif
2173         return 1;
2174 }
2175
2176 static inline void ext4_show_quota_options(struct seq_file *seq,
2177                                            struct super_block *sb)
2178 {
2179 #if defined(CONFIG_QUOTA)
2180         struct ext4_sb_info *sbi = EXT4_SB(sb);
2181         char *usr_qf_name, *grp_qf_name;
2182
2183         if (sbi->s_jquota_fmt) {
2184                 char *fmtname = "";
2185
2186                 switch (sbi->s_jquota_fmt) {
2187                 case QFMT_VFS_OLD:
2188                         fmtname = "vfsold";
2189                         break;
2190                 case QFMT_VFS_V0:
2191                         fmtname = "vfsv0";
2192                         break;
2193                 case QFMT_VFS_V1:
2194                         fmtname = "vfsv1";
2195                         break;
2196                 }
2197                 seq_printf(seq, ",jqfmt=%s", fmtname);
2198         }
2199
2200         rcu_read_lock();
2201         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2202         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2203         if (usr_qf_name)
2204                 seq_show_option(seq, "usrjquota", usr_qf_name);
2205         if (grp_qf_name)
2206                 seq_show_option(seq, "grpjquota", grp_qf_name);
2207         rcu_read_unlock();
2208 #endif
2209 }
2210
2211 static const char *token2str(int token)
2212 {
2213         const struct match_token *t;
2214
2215         for (t = tokens; t->token != Opt_err; t++)
2216                 if (t->token == token && !strchr(t->pattern, '='))
2217                         break;
2218         return t->pattern;
2219 }
2220
2221 /*
2222  * Show an option if
2223  *  - it's set to a non-default value OR
2224  *  - if the per-sb default is different from the global default
2225  */
2226 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2227                               int nodefs)
2228 {
2229         struct ext4_sb_info *sbi = EXT4_SB(sb);
2230         struct ext4_super_block *es = sbi->s_es;
2231         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2232         const struct mount_opts *m;
2233         char sep = nodefs ? '\n' : ',';
2234
2235 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2236 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2237
2238         if (sbi->s_sb_block != 1)
2239                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2240
2241         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2242                 int want_set = m->flags & MOPT_SET;
2243                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2244                     (m->flags & MOPT_CLEAR_ERR))
2245                         continue;
2246                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2247                         continue; /* skip if same as the default */
2248                 if ((want_set &&
2249                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2250                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2251                         continue; /* select Opt_noFoo vs Opt_Foo */
2252                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2253         }
2254
2255         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2256             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2257                 SEQ_OPTS_PRINT("resuid=%u",
2258                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2259         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2260             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2261                 SEQ_OPTS_PRINT("resgid=%u",
2262                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2263         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2264         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2265                 SEQ_OPTS_PUTS("errors=remount-ro");
2266         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2267                 SEQ_OPTS_PUTS("errors=continue");
2268         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2269                 SEQ_OPTS_PUTS("errors=panic");
2270         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2271                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2272         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2273                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2274         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2275                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2276         if (sb->s_flags & SB_I_VERSION)
2277                 SEQ_OPTS_PUTS("i_version");
2278         if (nodefs || sbi->s_stripe)
2279                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2280         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2281                         (sbi->s_mount_opt ^ def_mount_opt)) {
2282                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2283                         SEQ_OPTS_PUTS("data=journal");
2284                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2285                         SEQ_OPTS_PUTS("data=ordered");
2286                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2287                         SEQ_OPTS_PUTS("data=writeback");
2288         }
2289         if (nodefs ||
2290             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2291                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2292                                sbi->s_inode_readahead_blks);
2293
2294         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2295                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2296                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2297         if (nodefs || sbi->s_max_dir_size_kb)
2298                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2299         if (test_opt(sb, DATA_ERR_ABORT))
2300                 SEQ_OPTS_PUTS("data_err=abort");
2301         if (DUMMY_ENCRYPTION_ENABLED(sbi))
2302                 SEQ_OPTS_PUTS("test_dummy_encryption");
2303
2304         ext4_show_quota_options(seq, sb);
2305         return 0;
2306 }
2307
2308 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2309 {
2310         return _ext4_show_options(seq, root->d_sb, 0);
2311 }
2312
2313 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2314 {
2315         struct super_block *sb = seq->private;
2316         int rc;
2317
2318         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2319         rc = _ext4_show_options(seq, sb, 1);
2320         seq_puts(seq, "\n");
2321         return rc;
2322 }
2323
2324 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2325                             int read_only)
2326 {
2327         struct ext4_sb_info *sbi = EXT4_SB(sb);
2328         int err = 0;
2329
2330         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2331                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2332                          "forcing read-only mode");
2333                 err = -EROFS;
2334         }
2335         if (read_only)
2336                 goto done;
2337         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2338                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2339                          "running e2fsck is recommended");
2340         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2341                 ext4_msg(sb, KERN_WARNING,
2342                          "warning: mounting fs with errors, "
2343                          "running e2fsck is recommended");
2344         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2345                  le16_to_cpu(es->s_mnt_count) >=
2346                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2347                 ext4_msg(sb, KERN_WARNING,
2348                          "warning: maximal mount count reached, "
2349                          "running e2fsck is recommended");
2350         else if (le32_to_cpu(es->s_checkinterval) &&
2351                  (ext4_get_tstamp(es, s_lastcheck) +
2352                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2353                 ext4_msg(sb, KERN_WARNING,
2354                          "warning: checktime reached, "
2355                          "running e2fsck is recommended");
2356         if (!sbi->s_journal)
2357                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2358         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2359                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2360         le16_add_cpu(&es->s_mnt_count, 1);
2361         ext4_update_tstamp(es, s_mtime);
2362         if (sbi->s_journal)
2363                 ext4_set_feature_journal_needs_recovery(sb);
2364
2365         err = ext4_commit_super(sb, 1);
2366 done:
2367         if (test_opt(sb, DEBUG))
2368                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2369                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2370                         sb->s_blocksize,
2371                         sbi->s_groups_count,
2372                         EXT4_BLOCKS_PER_GROUP(sb),
2373                         EXT4_INODES_PER_GROUP(sb),
2374                         sbi->s_mount_opt, sbi->s_mount_opt2);
2375
2376         cleancache_init_fs(sb);
2377         return err;
2378 }
2379
2380 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2381 {
2382         struct ext4_sb_info *sbi = EXT4_SB(sb);
2383         struct flex_groups *new_groups;
2384         int size;
2385
2386         if (!sbi->s_log_groups_per_flex)
2387                 return 0;
2388
2389         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2390         if (size <= sbi->s_flex_groups_allocated)
2391                 return 0;
2392
2393         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
2394         new_groups = kvzalloc(size, GFP_KERNEL);
2395         if (!new_groups) {
2396                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
2397                          size / (int) sizeof(struct flex_groups));
2398                 return -ENOMEM;
2399         }
2400
2401         if (sbi->s_flex_groups) {
2402                 memcpy(new_groups, sbi->s_flex_groups,
2403                        (sbi->s_flex_groups_allocated *
2404                         sizeof(struct flex_groups)));
2405                 kvfree(sbi->s_flex_groups);
2406         }
2407         sbi->s_flex_groups = new_groups;
2408         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
2409         return 0;
2410 }
2411
2412 static int ext4_fill_flex_info(struct super_block *sb)
2413 {
2414         struct ext4_sb_info *sbi = EXT4_SB(sb);
2415         struct ext4_group_desc *gdp = NULL;
2416         ext4_group_t flex_group;
2417         int i, err;
2418
2419         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2420         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2421                 sbi->s_log_groups_per_flex = 0;
2422                 return 1;
2423         }
2424
2425         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2426         if (err)
2427                 goto failed;
2428
2429         for (i = 0; i < sbi->s_groups_count; i++) {
2430                 gdp = ext4_get_group_desc(sb, i, NULL);
2431
2432                 flex_group = ext4_flex_group(sbi, i);
2433                 atomic_add(ext4_free_inodes_count(sb, gdp),
2434                            &sbi->s_flex_groups[flex_group].free_inodes);
2435                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2436                              &sbi->s_flex_groups[flex_group].free_clusters);
2437                 atomic_add(ext4_used_dirs_count(sb, gdp),
2438                            &sbi->s_flex_groups[flex_group].used_dirs);
2439         }
2440
2441         return 1;
2442 failed:
2443         return 0;
2444 }
2445
2446 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2447                                    struct ext4_group_desc *gdp)
2448 {
2449         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2450         __u16 crc = 0;
2451         __le32 le_group = cpu_to_le32(block_group);
2452         struct ext4_sb_info *sbi = EXT4_SB(sb);
2453
2454         if (ext4_has_metadata_csum(sbi->s_sb)) {
2455                 /* Use new metadata_csum algorithm */
2456                 __u32 csum32;
2457                 __u16 dummy_csum = 0;
2458
2459                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2460                                      sizeof(le_group));
2461                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2462                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2463                                      sizeof(dummy_csum));
2464                 offset += sizeof(dummy_csum);
2465                 if (offset < sbi->s_desc_size)
2466                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2467                                              sbi->s_desc_size - offset);
2468
2469                 crc = csum32 & 0xFFFF;
2470                 goto out;
2471         }
2472
2473         /* old crc16 code */
2474         if (!ext4_has_feature_gdt_csum(sb))
2475                 return 0;
2476
2477         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2478         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2479         crc = crc16(crc, (__u8 *)gdp, offset);
2480         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2481         /* for checksum of struct ext4_group_desc do the rest...*/
2482         if (ext4_has_feature_64bit(sb) &&
2483             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2484                 crc = crc16(crc, (__u8 *)gdp + offset,
2485                             le16_to_cpu(sbi->s_es->s_desc_size) -
2486                                 offset);
2487
2488 out:
2489         return cpu_to_le16(crc);
2490 }
2491
2492 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2493                                 struct ext4_group_desc *gdp)
2494 {
2495         if (ext4_has_group_desc_csum(sb) &&
2496             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2497                 return 0;
2498
2499         return 1;
2500 }
2501
2502 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2503                               struct ext4_group_desc *gdp)
2504 {
2505         if (!ext4_has_group_desc_csum(sb))
2506                 return;
2507         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2508 }
2509
2510 /* Called at mount-time, super-block is locked */
2511 static int ext4_check_descriptors(struct super_block *sb,
2512                                   ext4_fsblk_t sb_block,
2513                                   ext4_group_t *first_not_zeroed)
2514 {
2515         struct ext4_sb_info *sbi = EXT4_SB(sb);
2516         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2517         ext4_fsblk_t last_block;
2518         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2519         ext4_fsblk_t block_bitmap;
2520         ext4_fsblk_t inode_bitmap;
2521         ext4_fsblk_t inode_table;
2522         int flexbg_flag = 0;
2523         ext4_group_t i, grp = sbi->s_groups_count;
2524
2525         if (ext4_has_feature_flex_bg(sb))
2526                 flexbg_flag = 1;
2527
2528         ext4_debug("Checking group descriptors");
2529
2530         for (i = 0; i < sbi->s_groups_count; i++) {
2531                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2532
2533                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2534                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2535                 else
2536                         last_block = first_block +
2537                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2538
2539                 if ((grp == sbi->s_groups_count) &&
2540                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2541                         grp = i;
2542
2543                 block_bitmap = ext4_block_bitmap(sb, gdp);
2544                 if (block_bitmap == sb_block) {
2545                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2546                                  "Block bitmap for group %u overlaps "
2547                                  "superblock", i);
2548                         if (!sb_rdonly(sb))
2549                                 return 0;
2550                 }
2551                 if (block_bitmap >= sb_block + 1 &&
2552                     block_bitmap <= last_bg_block) {
2553                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2554                                  "Block bitmap for group %u overlaps "
2555                                  "block group descriptors", i);
2556                         if (!sb_rdonly(sb))
2557                                 return 0;
2558                 }
2559                 if (block_bitmap < first_block || block_bitmap > last_block) {
2560                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2561                                "Block bitmap for group %u not in group "
2562                                "(block %llu)!", i, block_bitmap);
2563                         return 0;
2564                 }
2565                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2566                 if (inode_bitmap == sb_block) {
2567                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2568                                  "Inode bitmap for group %u overlaps "
2569                                  "superblock", i);
2570                         if (!sb_rdonly(sb))
2571                                 return 0;
2572                 }
2573                 if (inode_bitmap >= sb_block + 1 &&
2574                     inode_bitmap <= last_bg_block) {
2575                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2576                                  "Inode bitmap for group %u overlaps "
2577                                  "block group descriptors", i);
2578                         if (!sb_rdonly(sb))
2579                                 return 0;
2580                 }
2581                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2582                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2583                                "Inode bitmap for group %u not in group "
2584                                "(block %llu)!", i, inode_bitmap);
2585                         return 0;
2586                 }
2587                 inode_table = ext4_inode_table(sb, gdp);
2588                 if (inode_table == sb_block) {
2589                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2590                                  "Inode table for group %u overlaps "
2591                                  "superblock", i);
2592                         if (!sb_rdonly(sb))
2593                                 return 0;
2594                 }
2595                 if (inode_table >= sb_block + 1 &&
2596                     inode_table <= last_bg_block) {
2597                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2598                                  "Inode table for group %u overlaps "
2599                                  "block group descriptors", i);
2600                         if (!sb_rdonly(sb))
2601                                 return 0;
2602                 }
2603                 if (inode_table < first_block ||
2604                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2605                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2606                                "Inode table for group %u not in group "
2607                                "(block %llu)!", i, inode_table);
2608                         return 0;
2609                 }
2610                 ext4_lock_group(sb, i);
2611                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2612                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2613                                  "Checksum for group %u failed (%u!=%u)",
2614                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2615                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2616                         if (!sb_rdonly(sb)) {
2617                                 ext4_unlock_group(sb, i);
2618                                 return 0;
2619                         }
2620                 }
2621                 ext4_unlock_group(sb, i);
2622                 if (!flexbg_flag)
2623                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2624         }
2625         if (NULL != first_not_zeroed)
2626                 *first_not_zeroed = grp;
2627         return 1;
2628 }
2629
2630 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2631  * the superblock) which were deleted from all directories, but held open by
2632  * a process at the time of a crash.  We walk the list and try to delete these
2633  * inodes at recovery time (only with a read-write filesystem).
2634  *
2635  * In order to keep the orphan inode chain consistent during traversal (in
2636  * case of crash during recovery), we link each inode into the superblock
2637  * orphan list_head and handle it the same way as an inode deletion during
2638  * normal operation (which journals the operations for us).
2639  *
2640  * We only do an iget() and an iput() on each inode, which is very safe if we
2641  * accidentally point at an in-use or already deleted inode.  The worst that
2642  * can happen in this case is that we get a "bit already cleared" message from
2643  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2644  * e2fsck was run on this filesystem, and it must have already done the orphan
2645  * inode cleanup for us, so we can safely abort without any further action.
2646  */
2647 static void ext4_orphan_cleanup(struct super_block *sb,
2648                                 struct ext4_super_block *es)
2649 {
2650         unsigned int s_flags = sb->s_flags;
2651         int ret, nr_orphans = 0, nr_truncates = 0;
2652 #ifdef CONFIG_QUOTA
2653         int quota_update = 0;
2654         int i;
2655 #endif
2656         if (!es->s_last_orphan) {
2657                 jbd_debug(4, "no orphan inodes to clean up\n");
2658                 return;
2659         }
2660
2661         if (bdev_read_only(sb->s_bdev)) {
2662                 ext4_msg(sb, KERN_ERR, "write access "
2663                         "unavailable, skipping orphan cleanup");
2664                 return;
2665         }
2666
2667         /* Check if feature set would not allow a r/w mount */
2668         if (!ext4_feature_set_ok(sb, 0)) {
2669                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2670                          "unknown ROCOMPAT features");
2671                 return;
2672         }
2673
2674         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2675                 /* don't clear list on RO mount w/ errors */
2676                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2677                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2678                                   "clearing orphan list.\n");
2679                         es->s_last_orphan = 0;
2680                 }
2681                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2682                 return;
2683         }
2684
2685         if (s_flags & SB_RDONLY) {
2686                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2687                 sb->s_flags &= ~SB_RDONLY;
2688         }
2689 #ifdef CONFIG_QUOTA
2690         /* Needed for iput() to work correctly and not trash data */
2691         sb->s_flags |= SB_ACTIVE;
2692
2693         /*
2694          * Turn on quotas which were not enabled for read-only mounts if
2695          * filesystem has quota feature, so that they are updated correctly.
2696          */
2697         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2698                 int ret = ext4_enable_quotas(sb);
2699
2700                 if (!ret)
2701                         quota_update = 1;
2702                 else
2703                         ext4_msg(sb, KERN_ERR,
2704                                 "Cannot turn on quotas: error %d", ret);
2705         }
2706
2707         /* Turn on journaled quotas used for old sytle */
2708         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2709                 if (EXT4_SB(sb)->s_qf_names[i]) {
2710                         int ret = ext4_quota_on_mount(sb, i);
2711
2712                         if (!ret)
2713                                 quota_update = 1;
2714                         else
2715                                 ext4_msg(sb, KERN_ERR,
2716                                         "Cannot turn on journaled "
2717                                         "quota: type %d: error %d", i, ret);
2718                 }
2719         }
2720 #endif
2721
2722         while (es->s_last_orphan) {
2723                 struct inode *inode;
2724
2725                 /*
2726                  * We may have encountered an error during cleanup; if
2727                  * so, skip the rest.
2728                  */
2729                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2730                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2731                         es->s_last_orphan = 0;
2732                         break;
2733                 }
2734
2735                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2736                 if (IS_ERR(inode)) {
2737                         es->s_last_orphan = 0;
2738                         break;
2739                 }
2740
2741                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2742                 dquot_initialize(inode);
2743                 if (inode->i_nlink) {
2744                         if (test_opt(sb, DEBUG))
2745                                 ext4_msg(sb, KERN_DEBUG,
2746                                         "%s: truncating inode %lu to %lld bytes",
2747                                         __func__, inode->i_ino, inode->i_size);
2748                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2749                                   inode->i_ino, inode->i_size);
2750                         inode_lock(inode);
2751                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2752                         ret = ext4_truncate(inode);
2753                         if (ret)
2754                                 ext4_std_error(inode->i_sb, ret);
2755                         inode_unlock(inode);
2756                         nr_truncates++;
2757                 } else {
2758                         if (test_opt(sb, DEBUG))
2759                                 ext4_msg(sb, KERN_DEBUG,
2760                                         "%s: deleting unreferenced inode %lu",
2761                                         __func__, inode->i_ino);
2762                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2763                                   inode->i_ino);
2764                         nr_orphans++;
2765                 }
2766                 iput(inode);  /* The delete magic happens here! */
2767         }
2768
2769 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2770
2771         if (nr_orphans)
2772                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2773                        PLURAL(nr_orphans));
2774         if (nr_truncates)
2775                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2776                        PLURAL(nr_truncates));
2777 #ifdef CONFIG_QUOTA
2778         /* Turn off quotas if they were enabled for orphan cleanup */
2779         if (quota_update) {
2780                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2781                         if (sb_dqopt(sb)->files[i])
2782                                 dquot_quota_off(sb, i);
2783                 }
2784         }
2785 #endif
2786         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2787 }
2788
2789 /*
2790  * Maximal extent format file size.
2791  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2792  * extent format containers, within a sector_t, and within i_blocks
2793  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2794  * so that won't be a limiting factor.
2795  *
2796  * However there is other limiting factor. We do store extents in the form
2797  * of starting block and length, hence the resulting length of the extent
2798  * covering maximum file size must fit into on-disk format containers as
2799  * well. Given that length is always by 1 unit bigger than max unit (because
2800  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2801  *
2802  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2803  */
2804 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2805 {
2806         loff_t res;
2807         loff_t upper_limit = MAX_LFS_FILESIZE;
2808
2809         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
2810
2811         if (!has_huge_files) {
2812                 upper_limit = (1LL << 32) - 1;
2813
2814                 /* total blocks in file system block size */
2815                 upper_limit >>= (blkbits - 9);
2816                 upper_limit <<= blkbits;
2817         }
2818
2819         /*
2820          * 32-bit extent-start container, ee_block. We lower the maxbytes
2821          * by one fs block, so ee_len can cover the extent of maximum file
2822          * size
2823          */
2824         res = (1LL << 32) - 1;
2825         res <<= blkbits;
2826
2827         /* Sanity check against vm- & vfs- imposed limits */
2828         if (res > upper_limit)
2829                 res = upper_limit;
2830
2831         return res;
2832 }
2833
2834 /*
2835  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2836  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2837  * We need to be 1 filesystem block less than the 2^48 sector limit.
2838  */
2839 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2840 {
2841         loff_t res = EXT4_NDIR_BLOCKS;
2842         int meta_blocks;
2843         loff_t upper_limit;
2844         /* This is calculated to be the largest file size for a dense, block
2845          * mapped file such that the file's total number of 512-byte sectors,
2846          * including data and all indirect blocks, does not exceed (2^48 - 1).
2847          *
2848          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2849          * number of 512-byte sectors of the file.
2850          */
2851
2852         if (!has_huge_files) {
2853                 /*
2854                  * !has_huge_files or implies that the inode i_block field
2855                  * represents total file blocks in 2^32 512-byte sectors ==
2856                  * size of vfs inode i_blocks * 8
2857                  */
2858                 upper_limit = (1LL << 32) - 1;
2859
2860                 /* total blocks in file system block size */
2861                 upper_limit >>= (bits - 9);
2862
2863         } else {
2864                 /*
2865                  * We use 48 bit ext4_inode i_blocks
2866                  * With EXT4_HUGE_FILE_FL set the i_blocks
2867                  * represent total number of blocks in
2868                  * file system block size
2869                  */
2870                 upper_limit = (1LL << 48) - 1;
2871
2872         }
2873
2874         /* indirect blocks */
2875         meta_blocks = 1;
2876         /* double indirect blocks */
2877         meta_blocks += 1 + (1LL << (bits-2));
2878         /* tripple indirect blocks */
2879         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2880
2881         upper_limit -= meta_blocks;
2882         upper_limit <<= bits;
2883
2884         res += 1LL << (bits-2);
2885         res += 1LL << (2*(bits-2));
2886         res += 1LL << (3*(bits-2));
2887         res <<= bits;
2888         if (res > upper_limit)
2889                 res = upper_limit;
2890
2891         if (res > MAX_LFS_FILESIZE)
2892                 res = MAX_LFS_FILESIZE;
2893
2894         return res;
2895 }
2896
2897 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2898                                    ext4_fsblk_t logical_sb_block, int nr)
2899 {
2900         struct ext4_sb_info *sbi = EXT4_SB(sb);
2901         ext4_group_t bg, first_meta_bg;
2902         int has_super = 0;
2903
2904         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2905
2906         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2907                 return logical_sb_block + nr + 1;
2908         bg = sbi->s_desc_per_block * nr;
2909         if (ext4_bg_has_super(sb, bg))
2910                 has_super = 1;
2911
2912         /*
2913          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2914          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2915          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2916          * compensate.
2917          */
2918         if (sb->s_blocksize == 1024 && nr == 0 &&
2919             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
2920                 has_super++;
2921
2922         return (has_super + ext4_group_first_block_no(sb, bg));
2923 }
2924
2925 /**
2926  * ext4_get_stripe_size: Get the stripe size.
2927  * @sbi: In memory super block info
2928  *
2929  * If we have specified it via mount option, then
2930  * use the mount option value. If the value specified at mount time is
2931  * greater than the blocks per group use the super block value.
2932  * If the super block value is greater than blocks per group return 0.
2933  * Allocator needs it be less than blocks per group.
2934  *
2935  */
2936 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2937 {
2938         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2939         unsigned long stripe_width =
2940                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2941         int ret;
2942
2943         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2944                 ret = sbi->s_stripe;
2945         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2946                 ret = stripe_width;
2947         else if (stride && stride <= sbi->s_blocks_per_group)
2948                 ret = stride;
2949         else
2950                 ret = 0;
2951
2952         /*
2953          * If the stripe width is 1, this makes no sense and
2954          * we set it to 0 to turn off stripe handling code.
2955          */
2956         if (ret <= 1)
2957                 ret = 0;
2958
2959         return ret;
2960 }
2961
2962 /*
2963  * Check whether this filesystem can be mounted based on
2964  * the features present and the RDONLY/RDWR mount requested.
2965  * Returns 1 if this filesystem can be mounted as requested,
2966  * 0 if it cannot be.
2967  */
2968 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2969 {
2970         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2971                 ext4_msg(sb, KERN_ERR,
2972                         "Couldn't mount because of "
2973                         "unsupported optional features (%x)",
2974                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2975                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2976                 return 0;
2977         }
2978
2979 #ifndef CONFIG_UNICODE
2980         if (ext4_has_feature_casefold(sb)) {
2981                 ext4_msg(sb, KERN_ERR,
2982                          "Filesystem with casefold feature cannot be "
2983                          "mounted without CONFIG_UNICODE");
2984                 return 0;
2985         }
2986 #endif
2987
2988         if (readonly)
2989                 return 1;
2990
2991         if (ext4_has_feature_readonly(sb)) {
2992                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2993                 sb->s_flags |= SB_RDONLY;
2994                 return 1;
2995         }
2996
2997         /* Check that feature set is OK for a read-write mount */
2998         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2999                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3000                          "unsupported optional features (%x)",
3001                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3002                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3003                 return 0;
3004         }
3005         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3006                 ext4_msg(sb, KERN_ERR,
3007                          "Can't support bigalloc feature without "
3008                          "extents feature\n");
3009                 return 0;
3010         }
3011
3012 #if !defined(CONFIG_QUOTA) || !defined(CONFIG_QFMT_V2)
3013         if (!readonly && (ext4_has_feature_quota(sb) ||
3014                           ext4_has_feature_project(sb))) {
3015                 ext4_msg(sb, KERN_ERR,
3016                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3017                 return 0;
3018         }
3019 #endif  /* CONFIG_QUOTA */
3020         return 1;
3021 }
3022
3023 /*
3024  * This function is called once a day if we have errors logged
3025  * on the file system
3026  */
3027 static void print_daily_error_info(struct timer_list *t)
3028 {
3029         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3030         struct super_block *sb = sbi->s_sb;
3031         struct ext4_super_block *es = sbi->s_es;
3032
3033         if (es->s_error_count)
3034                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3035                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3036                          le32_to_cpu(es->s_error_count));
3037         if (es->s_first_error_time) {
3038                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3039                        sb->s_id,
3040                        ext4_get_tstamp(es, s_first_error_time),
3041                        (int) sizeof(es->s_first_error_func),
3042                        es->s_first_error_func,
3043                        le32_to_cpu(es->s_first_error_line));
3044                 if (es->s_first_error_ino)
3045                         printk(KERN_CONT ": inode %u",
3046                                le32_to_cpu(es->s_first_error_ino));
3047                 if (es->s_first_error_block)
3048                         printk(KERN_CONT ": block %llu", (unsigned long long)
3049                                le64_to_cpu(es->s_first_error_block));
3050                 printk(KERN_CONT "\n");
3051         }
3052         if (es->s_last_error_time) {
3053                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3054                        sb->s_id,
3055                        ext4_get_tstamp(es, s_last_error_time),
3056                        (int) sizeof(es->s_last_error_func),
3057                        es->s_last_error_func,
3058                        le32_to_cpu(es->s_last_error_line));
3059                 if (es->s_last_error_ino)
3060                         printk(KERN_CONT ": inode %u",
3061                                le32_to_cpu(es->s_last_error_ino));
3062                 if (es->s_last_error_block)
3063                         printk(KERN_CONT ": block %llu", (unsigned long long)
3064                                le64_to_cpu(es->s_last_error_block));
3065                 printk(KERN_CONT "\n");
3066         }
3067         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3068 }
3069
3070 /* Find next suitable group and run ext4_init_inode_table */
3071 static int ext4_run_li_request(struct ext4_li_request *elr)
3072 {
3073         struct ext4_group_desc *gdp = NULL;
3074         ext4_group_t group, ngroups;
3075         struct super_block *sb;
3076         unsigned long timeout = 0;
3077         int ret = 0;
3078
3079         sb = elr->lr_super;
3080         ngroups = EXT4_SB(sb)->s_groups_count;
3081
3082         for (group = elr->lr_next_group; group < ngroups; group++) {
3083                 gdp = ext4_get_group_desc(sb, group, NULL);
3084                 if (!gdp) {
3085                         ret = 1;
3086                         break;
3087                 }
3088
3089                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3090                         break;
3091         }
3092
3093         if (group >= ngroups)
3094                 ret = 1;
3095
3096         if (!ret) {
3097                 timeout = jiffies;
3098                 ret = ext4_init_inode_table(sb, group,
3099                                             elr->lr_timeout ? 0 : 1);
3100                 if (elr->lr_timeout == 0) {
3101                         timeout = (jiffies - timeout) *
3102                                   elr->lr_sbi->s_li_wait_mult;
3103                         elr->lr_timeout = timeout;
3104                 }
3105                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3106                 elr->lr_next_group = group + 1;
3107         }
3108         return ret;
3109 }
3110
3111 /*
3112  * Remove lr_request from the list_request and free the
3113  * request structure. Should be called with li_list_mtx held
3114  */
3115 static void ext4_remove_li_request(struct ext4_li_request *elr)
3116 {
3117         struct ext4_sb_info *sbi;
3118
3119         if (!elr)
3120                 return;
3121
3122         sbi = elr->lr_sbi;
3123
3124         list_del(&elr->lr_request);
3125         sbi->s_li_request = NULL;
3126         kfree(elr);
3127 }
3128
3129 static void ext4_unregister_li_request(struct super_block *sb)
3130 {
3131         mutex_lock(&ext4_li_mtx);
3132         if (!ext4_li_info) {
3133                 mutex_unlock(&ext4_li_mtx);
3134                 return;
3135         }
3136
3137         mutex_lock(&ext4_li_info->li_list_mtx);
3138         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3139         mutex_unlock(&ext4_li_info->li_list_mtx);
3140         mutex_unlock(&ext4_li_mtx);
3141 }
3142
3143 static struct task_struct *ext4_lazyinit_task;
3144
3145 /*
3146  * This is the function where ext4lazyinit thread lives. It walks
3147  * through the request list searching for next scheduled filesystem.
3148  * When such a fs is found, run the lazy initialization request
3149  * (ext4_rn_li_request) and keep track of the time spend in this
3150  * function. Based on that time we compute next schedule time of
3151  * the request. When walking through the list is complete, compute
3152  * next waking time and put itself into sleep.
3153  */
3154 static int ext4_lazyinit_thread(void *arg)
3155 {
3156         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3157         struct list_head *pos, *n;
3158         struct ext4_li_request *elr;
3159         unsigned long next_wakeup, cur;
3160
3161         BUG_ON(NULL == eli);
3162
3163 cont_thread:
3164         while (true) {
3165                 next_wakeup = MAX_JIFFY_OFFSET;
3166
3167                 mutex_lock(&eli->li_list_mtx);
3168                 if (list_empty(&eli->li_request_list)) {
3169                         mutex_unlock(&eli->li_list_mtx);
3170                         goto exit_thread;
3171                 }
3172                 list_for_each_safe(pos, n, &eli->li_request_list) {
3173                         int err = 0;
3174                         int progress = 0;
3175                         elr = list_entry(pos, struct ext4_li_request,
3176                                          lr_request);
3177
3178                         if (time_before(jiffies, elr->lr_next_sched)) {
3179                                 if (time_before(elr->lr_next_sched, next_wakeup))
3180                                         next_wakeup = elr->lr_next_sched;
3181                                 continue;
3182                         }
3183                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3184                                 if (sb_start_write_trylock(elr->lr_super)) {
3185                                         progress = 1;
3186                                         /*
3187                                          * We hold sb->s_umount, sb can not
3188                                          * be removed from the list, it is
3189                                          * now safe to drop li_list_mtx
3190                                          */
3191                                         mutex_unlock(&eli->li_list_mtx);
3192                                         err = ext4_run_li_request(elr);
3193                                         sb_end_write(elr->lr_super);
3194                                         mutex_lock(&eli->li_list_mtx);
3195                                         n = pos->next;
3196                                 }
3197                                 up_read((&elr->lr_super->s_umount));
3198                         }
3199                         /* error, remove the lazy_init job */
3200                         if (err) {
3201                                 ext4_remove_li_request(elr);
3202                                 continue;
3203                         }
3204                         if (!progress) {
3205                                 elr->lr_next_sched = jiffies +
3206                                         (prandom_u32()
3207                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3208                         }
3209                         if (time_before(elr->lr_next_sched, next_wakeup))
3210                                 next_wakeup = elr->lr_next_sched;
3211                 }
3212                 mutex_unlock(&eli->li_list_mtx);
3213
3214                 try_to_freeze();
3215
3216                 cur = jiffies;
3217                 if ((time_after_eq(cur, next_wakeup)) ||
3218                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3219                         cond_resched();
3220                         continue;
3221                 }
3222
3223                 schedule_timeout_interruptible(next_wakeup - cur);
3224
3225                 if (kthread_should_stop()) {
3226                         ext4_clear_request_list();
3227                         goto exit_thread;
3228                 }
3229         }
3230
3231 exit_thread:
3232         /*
3233          * It looks like the request list is empty, but we need
3234          * to check it under the li_list_mtx lock, to prevent any
3235          * additions into it, and of course we should lock ext4_li_mtx
3236          * to atomically free the list and ext4_li_info, because at
3237          * this point another ext4 filesystem could be registering
3238          * new one.
3239          */
3240         mutex_lock(&ext4_li_mtx);
3241         mutex_lock(&eli->li_list_mtx);
3242         if (!list_empty(&eli->li_request_list)) {
3243                 mutex_unlock(&eli->li_list_mtx);
3244                 mutex_unlock(&ext4_li_mtx);
3245                 goto cont_thread;
3246         }
3247         mutex_unlock(&eli->li_list_mtx);
3248         kfree(ext4_li_info);
3249         ext4_li_info = NULL;
3250         mutex_unlock(&ext4_li_mtx);
3251
3252         return 0;
3253 }
3254
3255 static void ext4_clear_request_list(void)
3256 {
3257         struct list_head *pos, *n;
3258         struct ext4_li_request *elr;
3259
3260         mutex_lock(&ext4_li_info->li_list_mtx);
3261         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3262                 elr = list_entry(pos, struct ext4_li_request,
3263                                  lr_request);
3264                 ext4_remove_li_request(elr);
3265         }
3266         mutex_unlock(&ext4_li_info->li_list_mtx);
3267 }
3268
3269 static int ext4_run_lazyinit_thread(void)
3270 {
3271         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3272                                          ext4_li_info, "ext4lazyinit");
3273         if (IS_ERR(ext4_lazyinit_task)) {
3274                 int err = PTR_ERR(ext4_lazyinit_task);
3275                 ext4_clear_request_list();
3276                 kfree(ext4_li_info);
3277                 ext4_li_info = NULL;
3278                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3279                                  "initialization thread\n",
3280                                  err);
3281                 return err;
3282         }
3283         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3284         return 0;
3285 }
3286
3287 /*
3288  * Check whether it make sense to run itable init. thread or not.
3289  * If there is at least one uninitialized inode table, return
3290  * corresponding group number, else the loop goes through all
3291  * groups and return total number of groups.
3292  */
3293 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3294 {
3295         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3296         struct ext4_group_desc *gdp = NULL;
3297
3298         if (!ext4_has_group_desc_csum(sb))
3299                 return ngroups;
3300
3301         for (group = 0; group < ngroups; group++) {
3302                 gdp = ext4_get_group_desc(sb, group, NULL);
3303                 if (!gdp)
3304                         continue;
3305
3306                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3307                         break;
3308         }
3309
3310         return group;
3311 }
3312
3313 static int ext4_li_info_new(void)
3314 {
3315         struct ext4_lazy_init *eli = NULL;
3316
3317         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3318         if (!eli)
3319                 return -ENOMEM;
3320
3321         INIT_LIST_HEAD(&eli->li_request_list);
3322         mutex_init(&eli->li_list_mtx);
3323
3324         eli->li_state |= EXT4_LAZYINIT_QUIT;
3325
3326         ext4_li_info = eli;
3327
3328         return 0;
3329 }
3330
3331 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3332                                             ext4_group_t start)
3333 {
3334         struct ext4_sb_info *sbi = EXT4_SB(sb);
3335         struct ext4_li_request *elr;
3336
3337         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3338         if (!elr)
3339                 return NULL;
3340
3341         elr->lr_super = sb;
3342         elr->lr_sbi = sbi;
3343         elr->lr_next_group = start;
3344
3345         /*
3346          * Randomize first schedule time of the request to
3347          * spread the inode table initialization requests
3348          * better.
3349          */
3350         elr->lr_next_sched = jiffies + (prandom_u32() %
3351                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3352         return elr;
3353 }
3354
3355 int ext4_register_li_request(struct super_block *sb,
3356                              ext4_group_t first_not_zeroed)
3357 {
3358         struct ext4_sb_info *sbi = EXT4_SB(sb);
3359         struct ext4_li_request *elr = NULL;
3360         ext4_group_t ngroups = sbi->s_groups_count;
3361         int ret = 0;
3362
3363         mutex_lock(&ext4_li_mtx);
3364         if (sbi->s_li_request != NULL) {
3365                 /*
3366                  * Reset timeout so it can be computed again, because
3367                  * s_li_wait_mult might have changed.
3368                  */
3369                 sbi->s_li_request->lr_timeout = 0;
3370                 goto out;
3371         }
3372
3373         if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3374             !test_opt(sb, INIT_INODE_TABLE))
3375                 goto out;
3376
3377         elr = ext4_li_request_new(sb, first_not_zeroed);
3378         if (!elr) {
3379                 ret = -ENOMEM;
3380                 goto out;
3381         }
3382
3383         if (NULL == ext4_li_info) {
3384                 ret = ext4_li_info_new();
3385                 if (ret)
3386                         goto out;
3387         }
3388
3389         mutex_lock(&ext4_li_info->li_list_mtx);
3390         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3391         mutex_unlock(&ext4_li_info->li_list_mtx);
3392
3393         sbi->s_li_request = elr;
3394         /*
3395          * set elr to NULL here since it has been inserted to
3396          * the request_list and the removal and free of it is
3397          * handled by ext4_clear_request_list from now on.
3398          */
3399         elr = NULL;
3400
3401         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3402                 ret = ext4_run_lazyinit_thread();
3403                 if (ret)
3404                         goto out;
3405         }
3406 out:
3407         mutex_unlock(&ext4_li_mtx);
3408         if (ret)
3409                 kfree(elr);
3410         return ret;
3411 }
3412
3413 /*
3414  * We do not need to lock anything since this is called on
3415  * module unload.
3416  */
3417 static void ext4_destroy_lazyinit_thread(void)
3418 {
3419         /*
3420          * If thread exited earlier
3421          * there's nothing to be done.
3422          */
3423         if (!ext4_li_info || !ext4_lazyinit_task)
3424                 return;
3425
3426         kthread_stop(ext4_lazyinit_task);
3427 }
3428
3429 static int set_journal_csum_feature_set(struct super_block *sb)
3430 {
3431         int ret = 1;
3432         int compat, incompat;
3433         struct ext4_sb_info *sbi = EXT4_SB(sb);
3434
3435         if (ext4_has_metadata_csum(sb)) {
3436                 /* journal checksum v3 */
3437                 compat = 0;
3438                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3439         } else {
3440                 /* journal checksum v1 */
3441                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3442                 incompat = 0;
3443         }
3444
3445         jbd2_journal_clear_features(sbi->s_journal,
3446                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3447                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3448                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3449         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3450                 ret = jbd2_journal_set_features(sbi->s_journal,
3451                                 compat, 0,
3452                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3453                                 incompat);
3454         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3455                 ret = jbd2_journal_set_features(sbi->s_journal,
3456                                 compat, 0,
3457                                 incompat);
3458                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3459                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3460         } else {
3461                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3462                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3463         }
3464
3465         return ret;
3466 }
3467
3468 /*
3469  * Note: calculating the overhead so we can be compatible with
3470  * historical BSD practice is quite difficult in the face of
3471  * clusters/bigalloc.  This is because multiple metadata blocks from
3472  * different block group can end up in the same allocation cluster.
3473  * Calculating the exact overhead in the face of clustered allocation
3474  * requires either O(all block bitmaps) in memory or O(number of block
3475  * groups**2) in time.  We will still calculate the superblock for
3476  * older file systems --- and if we come across with a bigalloc file
3477  * system with zero in s_overhead_clusters the estimate will be close to
3478  * correct especially for very large cluster sizes --- but for newer
3479  * file systems, it's better to calculate this figure once at mkfs
3480  * time, and store it in the superblock.  If the superblock value is
3481  * present (even for non-bigalloc file systems), we will use it.
3482  */
3483 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3484                           char *buf)
3485 {
3486         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3487         struct ext4_group_desc  *gdp;
3488         ext4_fsblk_t            first_block, last_block, b;
3489         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3490         int                     s, j, count = 0;
3491
3492         if (!ext4_has_feature_bigalloc(sb))
3493                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3494                         sbi->s_itb_per_group + 2);
3495
3496         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3497                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3498         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3499         for (i = 0; i < ngroups; i++) {
3500                 gdp = ext4_get_group_desc(sb, i, NULL);
3501                 b = ext4_block_bitmap(sb, gdp);
3502                 if (b >= first_block && b <= last_block) {
3503                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3504                         count++;
3505                 }
3506                 b = ext4_inode_bitmap(sb, gdp);
3507                 if (b >= first_block && b <= last_block) {
3508                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3509                         count++;
3510                 }
3511                 b = ext4_inode_table(sb, gdp);
3512                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3513                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3514                                 int c = EXT4_B2C(sbi, b - first_block);
3515                                 ext4_set_bit(c, buf);
3516                                 count++;
3517                         }
3518                 if (i != grp)
3519                         continue;
3520                 s = 0;
3521                 if (ext4_bg_has_super(sb, grp)) {
3522                         ext4_set_bit(s++, buf);
3523                         count++;
3524                 }
3525                 j = ext4_bg_num_gdb(sb, grp);
3526                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3527                         ext4_error(sb, "Invalid number of block group "
3528                                    "descriptor blocks: %d", j);
3529                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3530                 }
3531                 count += j;
3532                 for (; j > 0; j--)
3533                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3534         }
3535         if (!count)
3536                 return 0;
3537         return EXT4_CLUSTERS_PER_GROUP(sb) -
3538                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3539 }
3540
3541 /*
3542  * Compute the overhead and stash it in sbi->s_overhead
3543  */
3544 int ext4_calculate_overhead(struct super_block *sb)
3545 {
3546         struct ext4_sb_info *sbi = EXT4_SB(sb);
3547         struct ext4_super_block *es = sbi->s_es;
3548         struct inode *j_inode;
3549         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3550         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3551         ext4_fsblk_t overhead = 0;
3552         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3553
3554         if (!buf)
3555                 return -ENOMEM;
3556
3557         /*
3558          * Compute the overhead (FS structures).  This is constant
3559          * for a given filesystem unless the number of block groups
3560          * changes so we cache the previous value until it does.
3561          */
3562
3563         /*
3564          * All of the blocks before first_data_block are overhead
3565          */
3566         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3567
3568         /*
3569          * Add the overhead found in each block group
3570          */
3571         for (i = 0; i < ngroups; i++) {
3572                 int blks;
3573
3574                 blks = count_overhead(sb, i, buf);
3575                 overhead += blks;
3576                 if (blks)
3577                         memset(buf, 0, PAGE_SIZE);
3578                 cond_resched();
3579         }
3580
3581         /*
3582          * Add the internal journal blocks whether the journal has been
3583          * loaded or not
3584          */
3585         if (sbi->s_journal && !sbi->journal_bdev)
3586                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3587         else if (ext4_has_feature_journal(sb) && !sbi->s_journal) {
3588                 j_inode = ext4_get_journal_inode(sb, j_inum);
3589                 if (j_inode) {
3590                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3591                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3592                         iput(j_inode);
3593                 } else {
3594                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3595                 }
3596         }
3597         sbi->s_overhead = overhead;
3598         smp_wmb();
3599         free_page((unsigned long) buf);
3600         return 0;
3601 }
3602
3603 static void ext4_set_resv_clusters(struct super_block *sb)
3604 {
3605         ext4_fsblk_t resv_clusters;
3606         struct ext4_sb_info *sbi = EXT4_SB(sb);
3607
3608         /*
3609          * There's no need to reserve anything when we aren't using extents.
3610          * The space estimates are exact, there are no unwritten extents,
3611          * hole punching doesn't need new metadata... This is needed especially
3612          * to keep ext2/3 backward compatibility.
3613          */
3614         if (!ext4_has_feature_extents(sb))
3615                 return;
3616         /*
3617          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3618          * This should cover the situations where we can not afford to run
3619          * out of space like for example punch hole, or converting
3620          * unwritten extents in delalloc path. In most cases such
3621          * allocation would require 1, or 2 blocks, higher numbers are
3622          * very rare.
3623          */
3624         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3625                          sbi->s_cluster_bits);
3626
3627         do_div(resv_clusters, 50);
3628         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3629
3630         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3631 }
3632
3633 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3634 {
3635         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3636         char *orig_data = kstrdup(data, GFP_KERNEL);
3637         struct buffer_head *bh;
3638         struct ext4_super_block *es = NULL;
3639         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3640         ext4_fsblk_t block;
3641         ext4_fsblk_t sb_block = get_sb_block(&data);
3642         ext4_fsblk_t logical_sb_block;
3643         unsigned long offset = 0;
3644         unsigned long journal_devnum = 0;
3645         unsigned long def_mount_opts;
3646         struct inode *root;
3647         const char *descr;
3648         int ret = -ENOMEM;
3649         int blocksize, clustersize;
3650         unsigned int db_count;
3651         unsigned int i;
3652         int needs_recovery, has_huge_files, has_bigalloc;
3653         __u64 blocks_count;
3654         int err = 0;
3655         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3656         ext4_group_t first_not_zeroed;
3657
3658         if ((data && !orig_data) || !sbi)
3659                 goto out_free_base;
3660
3661         sbi->s_daxdev = dax_dev;
3662         sbi->s_blockgroup_lock =
3663                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3664         if (!sbi->s_blockgroup_lock)
3665                 goto out_free_base;
3666
3667         sb->s_fs_info = sbi;
3668         sbi->s_sb = sb;
3669         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3670         sbi->s_sb_block = sb_block;
3671         if (sb->s_bdev->bd_part)
3672                 sbi->s_sectors_written_start =
3673                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
3674
3675         /* Cleanup superblock name */
3676         strreplace(sb->s_id, '/', '!');
3677
3678         /* -EINVAL is default */
3679         ret = -EINVAL;
3680         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3681         if (!blocksize) {
3682                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3683                 goto out_fail;
3684         }
3685
3686         /*
3687          * The ext4 superblock will not be buffer aligned for other than 1kB
3688          * block sizes.  We need to calculate the offset from buffer start.
3689          */
3690         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3691                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3692                 offset = do_div(logical_sb_block, blocksize);
3693         } else {
3694                 logical_sb_block = sb_block;
3695         }
3696
3697         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3698                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3699                 goto out_fail;
3700         }
3701         /*
3702          * Note: s_es must be initialized as soon as possible because
3703          *       some ext4 macro-instructions depend on its value
3704          */
3705         es = (struct ext4_super_block *) (bh->b_data + offset);
3706         sbi->s_es = es;
3707         sb->s_magic = le16_to_cpu(es->s_magic);
3708         if (sb->s_magic != EXT4_SUPER_MAGIC)
3709                 goto cantfind_ext4;
3710         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3711
3712         /* Warn if metadata_csum and gdt_csum are both set. */
3713         if (ext4_has_feature_metadata_csum(sb) &&
3714             ext4_has_feature_gdt_csum(sb))
3715                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3716                              "redundant flags; please run fsck.");
3717
3718         /* Check for a known checksum algorithm */
3719         if (!ext4_verify_csum_type(sb, es)) {
3720                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3721                          "unknown checksum algorithm.");
3722                 silent = 1;
3723                 goto cantfind_ext4;
3724         }
3725
3726         /* Load the checksum driver */
3727         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3728         if (IS_ERR(sbi->s_chksum_driver)) {
3729                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3730                 ret = PTR_ERR(sbi->s_chksum_driver);
3731                 sbi->s_chksum_driver = NULL;
3732                 goto failed_mount;
3733         }
3734
3735         /* Check superblock checksum */
3736         if (!ext4_superblock_csum_verify(sb, es)) {
3737                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3738                          "invalid superblock checksum.  Run e2fsck?");
3739                 silent = 1;
3740                 ret = -EFSBADCRC;
3741                 goto cantfind_ext4;
3742         }
3743
3744         /* Precompute checksum seed for all metadata */
3745         if (ext4_has_feature_csum_seed(sb))
3746                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3747         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3748                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3749                                                sizeof(es->s_uuid));
3750
3751         /* Set defaults before we parse the mount options */
3752         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3753         set_opt(sb, INIT_INODE_TABLE);
3754         if (def_mount_opts & EXT4_DEFM_DEBUG)
3755                 set_opt(sb, DEBUG);
3756         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3757                 set_opt(sb, GRPID);
3758         if (def_mount_opts & EXT4_DEFM_UID16)
3759                 set_opt(sb, NO_UID32);
3760         /* xattr user namespace & acls are now defaulted on */
3761         set_opt(sb, XATTR_USER);
3762         set_opt(sb, DIOREAD_NOLOCK);
3763 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3764         set_opt(sb, POSIX_ACL);
3765 #endif
3766         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3767         if (ext4_has_metadata_csum(sb))
3768                 set_opt(sb, JOURNAL_CHECKSUM);
3769
3770         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3771                 set_opt(sb, JOURNAL_DATA);
3772         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3773                 set_opt(sb, ORDERED_DATA);
3774         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3775                 set_opt(sb, WRITEBACK_DATA);
3776
3777         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3778                 set_opt(sb, ERRORS_PANIC);
3779         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3780                 set_opt(sb, ERRORS_CONT);
3781         else
3782                 set_opt(sb, ERRORS_RO);
3783         /* block_validity enabled by default; disable with noblock_validity */
3784         set_opt(sb, BLOCK_VALIDITY);
3785         if (def_mount_opts & EXT4_DEFM_DISCARD)
3786                 set_opt(sb, DISCARD);
3787
3788         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3789         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3790         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3791         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3792         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3793
3794         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3795                 set_opt(sb, BARRIER);
3796
3797         /*
3798          * enable delayed allocation by default
3799          * Use -o nodelalloc to turn it off
3800          */
3801         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3802             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3803                 set_opt(sb, DELALLOC);
3804
3805         /*
3806          * set default s_li_wait_mult for lazyinit, for the case there is
3807          * no mount option specified.
3808          */
3809         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3810
3811         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3812         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3813             blocksize > EXT4_MAX_BLOCK_SIZE) {
3814                 ext4_msg(sb, KERN_ERR,
3815                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3816                          blocksize, le32_to_cpu(es->s_log_block_size));
3817                 goto failed_mount;
3818         }
3819
3820         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3821                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3822                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3823         } else {
3824                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3825                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3826                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
3827                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
3828                                  sbi->s_first_ino);
3829                         goto failed_mount;
3830                 }
3831                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3832                     (!is_power_of_2(sbi->s_inode_size)) ||
3833                     (sbi->s_inode_size > blocksize)) {
3834                         ext4_msg(sb, KERN_ERR,
3835                                "unsupported inode size: %d",
3836                                sbi->s_inode_size);
3837                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
3838                         goto failed_mount;
3839                 }
3840                 /*
3841                  * i_atime_extra is the last extra field available for
3842                  * [acm]times in struct ext4_inode. Checking for that
3843                  * field should suffice to ensure we have extra space
3844                  * for all three.
3845                  */
3846                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
3847                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
3848                         sb->s_time_gran = 1;
3849                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
3850                 } else {
3851                         sb->s_time_gran = NSEC_PER_SEC;
3852                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
3853                 }
3854                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
3855         }
3856         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3857                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3858                         EXT4_GOOD_OLD_INODE_SIZE;
3859                 if (ext4_has_feature_extra_isize(sb)) {
3860                         unsigned v, max = (sbi->s_inode_size -
3861                                            EXT4_GOOD_OLD_INODE_SIZE);
3862
3863                         v = le16_to_cpu(es->s_want_extra_isize);
3864                         if (v > max) {
3865                                 ext4_msg(sb, KERN_ERR,
3866                                          "bad s_want_extra_isize: %d", v);
3867                                 goto failed_mount;
3868                         }
3869                         if (sbi->s_want_extra_isize < v)
3870                                 sbi->s_want_extra_isize = v;
3871
3872                         v = le16_to_cpu(es->s_min_extra_isize);
3873                         if (v > max) {
3874                                 ext4_msg(sb, KERN_ERR,
3875                                          "bad s_min_extra_isize: %d", v);
3876                                 goto failed_mount;
3877                         }
3878                         if (sbi->s_want_extra_isize < v)
3879                                 sbi->s_want_extra_isize = v;
3880                 }
3881         }
3882
3883         if (sbi->s_es->s_mount_opts[0]) {
3884                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3885                                               sizeof(sbi->s_es->s_mount_opts),
3886                                               GFP_KERNEL);
3887                 if (!s_mount_opts)
3888                         goto failed_mount;
3889                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
3890                                    &journal_ioprio, 0)) {
3891                         ext4_msg(sb, KERN_WARNING,
3892                                  "failed to parse options in superblock: %s",
3893                                  s_mount_opts);
3894                 }
3895                 kfree(s_mount_opts);
3896         }
3897         sbi->s_def_mount_opt = sbi->s_mount_opt;
3898         if (!parse_options((char *) data, sb, &journal_devnum,
3899                            &journal_ioprio, 0))
3900                 goto failed_mount;
3901
3902 #ifdef CONFIG_UNICODE
3903         if (ext4_has_feature_casefold(sb) && !sbi->s_encoding) {
3904                 const struct ext4_sb_encodings *encoding_info;
3905                 struct unicode_map *encoding;
3906                 __u16 encoding_flags;
3907
3908                 if (ext4_has_feature_encrypt(sb)) {
3909                         ext4_msg(sb, KERN_ERR,
3910                                  "Can't mount with encoding and encryption");
3911                         goto failed_mount;
3912                 }
3913
3914                 if (ext4_sb_read_encoding(es, &encoding_info,
3915                                           &encoding_flags)) {
3916                         ext4_msg(sb, KERN_ERR,
3917                                  "Encoding requested by superblock is unknown");
3918                         goto failed_mount;
3919                 }
3920
3921                 encoding = utf8_load(encoding_info->version);
3922                 if (IS_ERR(encoding)) {
3923                         ext4_msg(sb, KERN_ERR,
3924                                  "can't mount with superblock charset: %s-%s "
3925                                  "not supported by the kernel. flags: 0x%x.",
3926                                  encoding_info->name, encoding_info->version,
3927                                  encoding_flags);
3928                         goto failed_mount;
3929                 }
3930                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
3931                          "%s-%s with flags 0x%hx", encoding_info->name,
3932                          encoding_info->version?:"\b", encoding_flags);
3933
3934                 sbi->s_encoding = encoding;
3935                 sbi->s_encoding_flags = encoding_flags;
3936         }
3937 #endif
3938
3939         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3940                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, and O_DIRECT support!\n");
3941                 clear_opt(sb, DIOREAD_NOLOCK);
3942                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3943                         ext4_msg(sb, KERN_ERR, "can't mount with "
3944                                  "both data=journal and delalloc");
3945                         goto failed_mount;
3946                 }
3947                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3948                         ext4_msg(sb, KERN_ERR, "can't mount with "
3949                                  "both data=journal and dioread_nolock");
3950                         goto failed_mount;
3951                 }
3952                 if (test_opt(sb, DAX)) {
3953                         ext4_msg(sb, KERN_ERR, "can't mount with "
3954                                  "both data=journal and dax");
3955                         goto failed_mount;
3956                 }
3957                 if (ext4_has_feature_encrypt(sb)) {
3958                         ext4_msg(sb, KERN_WARNING,
3959                                  "encrypted files will use data=ordered "
3960                                  "instead of data journaling mode");
3961                 }
3962                 if (test_opt(sb, DELALLOC))
3963                         clear_opt(sb, DELALLOC);
3964         } else {
3965                 sb->s_iflags |= SB_I_CGROUPWB;
3966         }
3967
3968         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
3969                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
3970
3971         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3972             (ext4_has_compat_features(sb) ||
3973              ext4_has_ro_compat_features(sb) ||
3974              ext4_has_incompat_features(sb)))
3975                 ext4_msg(sb, KERN_WARNING,
3976                        "feature flags set on rev 0 fs, "
3977                        "running e2fsck is recommended");
3978
3979         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3980                 set_opt2(sb, HURD_COMPAT);
3981                 if (ext4_has_feature_64bit(sb)) {
3982                         ext4_msg(sb, KERN_ERR,
3983                                  "The Hurd can't support 64-bit file systems");
3984                         goto failed_mount;
3985                 }
3986
3987                 /*
3988                  * ea_inode feature uses l_i_version field which is not
3989                  * available in HURD_COMPAT mode.
3990                  */
3991                 if (ext4_has_feature_ea_inode(sb)) {
3992                         ext4_msg(sb, KERN_ERR,
3993                                  "ea_inode feature is not supported for Hurd");
3994                         goto failed_mount;
3995                 }
3996         }
3997
3998         if (IS_EXT2_SB(sb)) {
3999                 if (ext2_feature_set_ok(sb))
4000                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4001                                  "using the ext4 subsystem");
4002                 else {
4003                         /*
4004                          * If we're probing be silent, if this looks like
4005                          * it's actually an ext[34] filesystem.
4006                          */
4007                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4008                                 goto failed_mount;
4009                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4010                                  "to feature incompatibilities");
4011                         goto failed_mount;
4012                 }
4013         }
4014
4015         if (IS_EXT3_SB(sb)) {
4016                 if (ext3_feature_set_ok(sb))
4017                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4018                                  "using the ext4 subsystem");
4019                 else {
4020                         /*
4021                          * If we're probing be silent, if this looks like
4022                          * it's actually an ext4 filesystem.
4023                          */
4024                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4025                                 goto failed_mount;
4026                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4027                                  "to feature incompatibilities");
4028                         goto failed_mount;
4029                 }
4030         }
4031
4032         /*
4033          * Check feature flags regardless of the revision level, since we
4034          * previously didn't change the revision level when setting the flags,
4035          * so there is a chance incompat flags are set on a rev 0 filesystem.
4036          */
4037         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4038                 goto failed_mount;
4039
4040         if (le32_to_cpu(es->s_log_block_size) >
4041             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4042                 ext4_msg(sb, KERN_ERR,
4043                          "Invalid log block size: %u",
4044                          le32_to_cpu(es->s_log_block_size));
4045                 goto failed_mount;
4046         }
4047         if (le32_to_cpu(es->s_log_cluster_size) >
4048             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4049                 ext4_msg(sb, KERN_ERR,
4050                          "Invalid log cluster size: %u",
4051                          le32_to_cpu(es->s_log_cluster_size));
4052                 goto failed_mount;
4053         }
4054
4055         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4056                 ext4_msg(sb, KERN_ERR,
4057                          "Number of reserved GDT blocks insanely large: %d",
4058                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4059                 goto failed_mount;
4060         }
4061
4062         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
4063                 if (ext4_has_feature_inline_data(sb)) {
4064                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4065                                         " that may contain inline data");
4066                         goto failed_mount;
4067                 }
4068                 if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
4069                         ext4_msg(sb, KERN_ERR,
4070                                 "DAX unsupported by block device.");
4071                         goto failed_mount;
4072                 }
4073         }
4074
4075         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4076                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4077                          es->s_encryption_level);
4078                 goto failed_mount;
4079         }
4080
4081         if (sb->s_blocksize != blocksize) {
4082                 /* Validate the filesystem blocksize */
4083                 if (!sb_set_blocksize(sb, blocksize)) {
4084                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4085                                         blocksize);
4086                         goto failed_mount;
4087                 }
4088
4089                 brelse(bh);
4090                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4091                 offset = do_div(logical_sb_block, blocksize);
4092                 bh = sb_bread_unmovable(sb, logical_sb_block);
4093                 if (!bh) {
4094                         ext4_msg(sb, KERN_ERR,
4095                                "Can't read superblock on 2nd try");
4096                         goto failed_mount;
4097                 }
4098                 es = (struct ext4_super_block *)(bh->b_data + offset);
4099                 sbi->s_es = es;
4100                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4101                         ext4_msg(sb, KERN_ERR,
4102                                "Magic mismatch, very weird!");
4103                         goto failed_mount;
4104                 }
4105         }
4106
4107         has_huge_files = ext4_has_feature_huge_file(sb);
4108         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4109                                                       has_huge_files);
4110         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4111
4112         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4113         if (ext4_has_feature_64bit(sb)) {
4114                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4115                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4116                     !is_power_of_2(sbi->s_desc_size)) {
4117                         ext4_msg(sb, KERN_ERR,
4118                                "unsupported descriptor size %lu",
4119                                sbi->s_desc_size);
4120                         goto failed_mount;
4121                 }
4122         } else
4123                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4124
4125         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4126         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4127
4128         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4129         if (sbi->s_inodes_per_block == 0)
4130                 goto cantfind_ext4;
4131         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4132             sbi->s_inodes_per_group > blocksize * 8) {
4133                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4134                          sbi->s_blocks_per_group);
4135                 goto failed_mount;
4136         }
4137         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4138                                         sbi->s_inodes_per_block;
4139         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4140         sbi->s_sbh = bh;
4141         sbi->s_mount_state = le16_to_cpu(es->s_state);
4142         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4143         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4144
4145         for (i = 0; i < 4; i++)
4146                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4147         sbi->s_def_hash_version = es->s_def_hash_version;
4148         if (ext4_has_feature_dir_index(sb)) {
4149                 i = le32_to_cpu(es->s_flags);
4150                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4151                         sbi->s_hash_unsigned = 3;
4152                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4153 #ifdef __CHAR_UNSIGNED__
4154                         if (!sb_rdonly(sb))
4155                                 es->s_flags |=
4156                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4157                         sbi->s_hash_unsigned = 3;
4158 #else
4159                         if (!sb_rdonly(sb))
4160                                 es->s_flags |=
4161                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4162 #endif
4163                 }
4164         }
4165
4166         /* Handle clustersize */
4167         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4168         has_bigalloc = ext4_has_feature_bigalloc(sb);
4169         if (has_bigalloc) {
4170                 if (clustersize < blocksize) {
4171                         ext4_msg(sb, KERN_ERR,
4172                                  "cluster size (%d) smaller than "
4173                                  "block size (%d)", clustersize, blocksize);
4174                         goto failed_mount;
4175                 }
4176                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4177                         le32_to_cpu(es->s_log_block_size);
4178                 sbi->s_clusters_per_group =
4179                         le32_to_cpu(es->s_clusters_per_group);
4180                 if (sbi->s_clusters_per_group > blocksize * 8) {
4181                         ext4_msg(sb, KERN_ERR,
4182                                  "#clusters per group too big: %lu",
4183                                  sbi->s_clusters_per_group);
4184                         goto failed_mount;
4185                 }
4186                 if (sbi->s_blocks_per_group !=
4187                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4188                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4189                                  "clusters per group (%lu) inconsistent",
4190                                  sbi->s_blocks_per_group,
4191                                  sbi->s_clusters_per_group);
4192                         goto failed_mount;
4193                 }
4194         } else {
4195                 if (clustersize != blocksize) {
4196                         ext4_msg(sb, KERN_ERR,
4197                                  "fragment/cluster size (%d) != "
4198                                  "block size (%d)", clustersize, blocksize);
4199                         goto failed_mount;
4200                 }
4201                 if (sbi->s_blocks_per_group > blocksize * 8) {
4202                         ext4_msg(sb, KERN_ERR,
4203                                  "#blocks per group too big: %lu",
4204                                  sbi->s_blocks_per_group);
4205                         goto failed_mount;
4206                 }
4207                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4208                 sbi->s_cluster_bits = 0;
4209         }
4210         sbi->s_cluster_ratio = clustersize / blocksize;
4211
4212         /* Do we have standard group size of clustersize * 8 blocks ? */
4213         if (sbi->s_blocks_per_group == clustersize << 3)
4214                 set_opt2(sb, STD_GROUP_SIZE);
4215
4216         /*
4217          * Test whether we have more sectors than will fit in sector_t,
4218          * and whether the max offset is addressable by the page cache.
4219          */
4220         err = generic_check_addressable(sb->s_blocksize_bits,
4221                                         ext4_blocks_count(es));
4222         if (err) {
4223                 ext4_msg(sb, KERN_ERR, "filesystem"
4224                          " too large to mount safely on this system");
4225                 goto failed_mount;
4226         }
4227
4228         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4229                 goto cantfind_ext4;
4230
4231         /* check blocks count against device size */
4232         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4233         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4234                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4235                        "exceeds size of device (%llu blocks)",
4236                        ext4_blocks_count(es), blocks_count);
4237                 goto failed_mount;
4238         }
4239
4240         /*
4241          * It makes no sense for the first data block to be beyond the end
4242          * of the filesystem.
4243          */
4244         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4245                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4246                          "block %u is beyond end of filesystem (%llu)",
4247                          le32_to_cpu(es->s_first_data_block),
4248                          ext4_blocks_count(es));
4249                 goto failed_mount;
4250         }
4251         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4252             (sbi->s_cluster_ratio == 1)) {
4253                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4254                          "block is 0 with a 1k block and cluster size");
4255                 goto failed_mount;
4256         }
4257
4258         blocks_count = (ext4_blocks_count(es) -
4259                         le32_to_cpu(es->s_first_data_block) +
4260                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4261         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4262         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4263                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
4264                        "(block count %llu, first data block %u, "
4265                        "blocks per group %lu)", sbi->s_groups_count,
4266                        ext4_blocks_count(es),
4267                        le32_to_cpu(es->s_first_data_block),
4268                        EXT4_BLOCKS_PER_GROUP(sb));
4269                 goto failed_mount;
4270         }
4271         sbi->s_groups_count = blocks_count;
4272         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4273                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4274         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4275             le32_to_cpu(es->s_inodes_count)) {
4276                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4277                          le32_to_cpu(es->s_inodes_count),
4278                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4279                 ret = -EINVAL;
4280                 goto failed_mount;
4281         }
4282         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4283                    EXT4_DESC_PER_BLOCK(sb);
4284         if (ext4_has_feature_meta_bg(sb)) {
4285                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4286                         ext4_msg(sb, KERN_WARNING,
4287                                  "first meta block group too large: %u "
4288                                  "(group descriptor block count %u)",
4289                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4290                         goto failed_mount;
4291                 }
4292         }
4293         sbi->s_group_desc = kvmalloc_array(db_count,
4294                                            sizeof(struct buffer_head *),
4295                                            GFP_KERNEL);
4296         if (sbi->s_group_desc == NULL) {
4297                 ext4_msg(sb, KERN_ERR, "not enough memory");
4298                 ret = -ENOMEM;
4299                 goto failed_mount;
4300         }
4301
4302         bgl_lock_init(sbi->s_blockgroup_lock);
4303
4304         /* Pre-read the descriptors into the buffer cache */
4305         for (i = 0; i < db_count; i++) {
4306                 block = descriptor_loc(sb, logical_sb_block, i);
4307                 sb_breadahead(sb, block);
4308         }
4309
4310         for (i = 0; i < db_count; i++) {
4311                 block = descriptor_loc(sb, logical_sb_block, i);
4312                 sbi->s_group_desc[i] = sb_bread_unmovable(sb, block);
4313                 if (!sbi->s_group_desc[i]) {
4314                         ext4_msg(sb, KERN_ERR,
4315                                "can't read group descriptor %d", i);
4316                         db_count = i;
4317                         goto failed_mount2;
4318                 }
4319         }
4320         sbi->s_gdb_count = db_count;
4321         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4322                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4323                 ret = -EFSCORRUPTED;
4324                 goto failed_mount2;
4325         }
4326
4327         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4328
4329         /* Register extent status tree shrinker */
4330         if (ext4_es_register_shrinker(sbi))
4331                 goto failed_mount3;
4332
4333         sbi->s_stripe = ext4_get_stripe_size(sbi);
4334         sbi->s_extent_max_zeroout_kb = 32;
4335
4336         /*
4337          * set up enough so that it can read an inode
4338          */
4339         sb->s_op = &ext4_sops;
4340         sb->s_export_op = &ext4_export_ops;
4341         sb->s_xattr = ext4_xattr_handlers;
4342 #ifdef CONFIG_FS_ENCRYPTION
4343         sb->s_cop = &ext4_cryptops;
4344 #endif
4345 #ifdef CONFIG_FS_VERITY
4346         sb->s_vop = &ext4_verityops;
4347 #endif
4348 #ifdef CONFIG_QUOTA
4349         sb->dq_op = &ext4_quota_operations;
4350         if (ext4_has_feature_quota(sb))
4351                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4352         else
4353                 sb->s_qcop = &ext4_qctl_operations;
4354         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4355 #endif
4356         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4357
4358         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4359         mutex_init(&sbi->s_orphan_lock);
4360
4361         sb->s_root = NULL;
4362
4363         needs_recovery = (es->s_last_orphan != 0 ||
4364                           ext4_has_feature_journal_needs_recovery(sb));
4365
4366         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4367                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4368                         goto failed_mount3a;
4369
4370         /*
4371          * The first inode we look at is the journal inode.  Don't try
4372          * root first: it may be modified in the journal!
4373          */
4374         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4375                 err = ext4_load_journal(sb, es, journal_devnum);
4376                 if (err)
4377                         goto failed_mount3a;
4378         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4379                    ext4_has_feature_journal_needs_recovery(sb)) {
4380                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4381                        "suppressed and not mounted read-only");
4382                 goto failed_mount_wq;
4383         } else {
4384                 /* Nojournal mode, all journal mount options are illegal */
4385                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4386                         ext4_msg(sb, KERN_ERR, "can't mount with "
4387                                  "journal_checksum, fs mounted w/o journal");
4388                         goto failed_mount_wq;
4389                 }
4390                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4391                         ext4_msg(sb, KERN_ERR, "can't mount with "
4392                                  "journal_async_commit, fs mounted w/o journal");
4393                         goto failed_mount_wq;
4394                 }
4395                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4396                         ext4_msg(sb, KERN_ERR, "can't mount with "
4397                                  "commit=%lu, fs mounted w/o journal",
4398                                  sbi->s_commit_interval / HZ);
4399                         goto failed_mount_wq;
4400                 }
4401                 if (EXT4_MOUNT_DATA_FLAGS &
4402                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4403                         ext4_msg(sb, KERN_ERR, "can't mount with "
4404                                  "data=, fs mounted w/o journal");
4405                         goto failed_mount_wq;
4406                 }
4407                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4408                 clear_opt(sb, JOURNAL_CHECKSUM);
4409                 clear_opt(sb, DATA_FLAGS);
4410                 sbi->s_journal = NULL;
4411                 needs_recovery = 0;
4412                 goto no_journal;
4413         }
4414
4415         if (ext4_has_feature_64bit(sb) &&
4416             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4417                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4418                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4419                 goto failed_mount_wq;
4420         }
4421
4422         if (!set_journal_csum_feature_set(sb)) {
4423                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4424                          "feature set");
4425                 goto failed_mount_wq;
4426         }
4427
4428         /* We have now updated the journal if required, so we can
4429          * validate the data journaling mode. */
4430         switch (test_opt(sb, DATA_FLAGS)) {
4431         case 0:
4432                 /* No mode set, assume a default based on the journal
4433                  * capabilities: ORDERED_DATA if the journal can
4434                  * cope, else JOURNAL_DATA
4435                  */
4436                 if (jbd2_journal_check_available_features
4437                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4438                         set_opt(sb, ORDERED_DATA);
4439                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4440                 } else {
4441                         set_opt(sb, JOURNAL_DATA);
4442                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4443                 }
4444                 break;
4445
4446         case EXT4_MOUNT_ORDERED_DATA:
4447         case EXT4_MOUNT_WRITEBACK_DATA:
4448                 if (!jbd2_journal_check_available_features
4449                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4450                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4451                                "requested data journaling mode");
4452                         goto failed_mount_wq;
4453                 }
4454         default:
4455                 break;
4456         }
4457
4458         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4459             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4460                 ext4_msg(sb, KERN_ERR, "can't mount with "
4461                         "journal_async_commit in data=ordered mode");
4462                 goto failed_mount_wq;
4463         }
4464
4465         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4466
4467         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4468
4469 no_journal:
4470         if (!test_opt(sb, NO_MBCACHE)) {
4471                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4472                 if (!sbi->s_ea_block_cache) {
4473                         ext4_msg(sb, KERN_ERR,
4474                                  "Failed to create ea_block_cache");
4475                         goto failed_mount_wq;
4476                 }
4477
4478                 if (ext4_has_feature_ea_inode(sb)) {
4479                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4480                         if (!sbi->s_ea_inode_cache) {
4481                                 ext4_msg(sb, KERN_ERR,
4482                                          "Failed to create ea_inode_cache");
4483                                 goto failed_mount_wq;
4484                         }
4485                 }
4486         }
4487
4488         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4489                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4490                 goto failed_mount_wq;
4491         }
4492
4493         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4494             !ext4_has_feature_encrypt(sb)) {
4495                 ext4_set_feature_encrypt(sb);
4496                 ext4_commit_super(sb, 1);
4497         }
4498
4499         /*
4500          * Get the # of file system overhead blocks from the
4501          * superblock if present.
4502          */
4503         if (es->s_overhead_clusters)
4504                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4505         else {
4506                 err = ext4_calculate_overhead(sb);
4507                 if (err)
4508                         goto failed_mount_wq;
4509         }
4510
4511         /*
4512          * The maximum number of concurrent works can be high and
4513          * concurrency isn't really necessary.  Limit it to 1.
4514          */
4515         EXT4_SB(sb)->rsv_conversion_wq =
4516                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4517         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4518                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4519                 ret = -ENOMEM;
4520                 goto failed_mount4;
4521         }
4522
4523         /*
4524          * The jbd2_journal_load will have done any necessary log recovery,
4525          * so we can safely mount the rest of the filesystem now.
4526          */
4527
4528         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4529         if (IS_ERR(root)) {
4530                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4531                 ret = PTR_ERR(root);
4532                 root = NULL;
4533                 goto failed_mount4;
4534         }
4535         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4536                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4537                 iput(root);
4538                 goto failed_mount4;
4539         }
4540
4541 #ifdef CONFIG_UNICODE
4542         if (sbi->s_encoding)
4543                 sb->s_d_op = &ext4_dentry_ops;
4544 #endif
4545
4546         sb->s_root = d_make_root(root);
4547         if (!sb->s_root) {
4548                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4549                 ret = -ENOMEM;
4550                 goto failed_mount4;
4551         }
4552
4553         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4554         if (ret == -EROFS) {
4555                 sb->s_flags |= SB_RDONLY;
4556                 ret = 0;
4557         } else if (ret)
4558                 goto failed_mount4a;
4559
4560         ext4_set_resv_clusters(sb);
4561
4562         err = ext4_setup_system_zone(sb);
4563         if (err) {
4564                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4565                          "zone (%d)", err);
4566                 goto failed_mount4a;
4567         }
4568
4569         ext4_ext_init(sb);
4570         err = ext4_mb_init(sb);
4571         if (err) {
4572                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4573                          err);
4574                 goto failed_mount5;
4575         }
4576
4577         block = ext4_count_free_clusters(sb);
4578         ext4_free_blocks_count_set(sbi->s_es,
4579                                    EXT4_C2B(sbi, block));
4580         ext4_superblock_csum_set(sb);
4581         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4582                                   GFP_KERNEL);
4583         if (!err) {
4584                 unsigned long freei = ext4_count_free_inodes(sb);
4585                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4586                 ext4_superblock_csum_set(sb);
4587                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4588                                           GFP_KERNEL);
4589         }
4590         if (!err)
4591                 err = percpu_counter_init(&sbi->s_dirs_counter,
4592                                           ext4_count_dirs(sb), GFP_KERNEL);
4593         if (!err)
4594                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4595                                           GFP_KERNEL);
4596         if (!err)
4597                 err = percpu_init_rwsem(&sbi->s_journal_flag_rwsem);
4598
4599         if (err) {
4600                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4601                 goto failed_mount6;
4602         }
4603
4604         if (ext4_has_feature_flex_bg(sb))
4605                 if (!ext4_fill_flex_info(sb)) {
4606                         ext4_msg(sb, KERN_ERR,
4607                                "unable to initialize "
4608                                "flex_bg meta info!");
4609                         goto failed_mount6;
4610                 }
4611
4612         err = ext4_register_li_request(sb, first_not_zeroed);
4613         if (err)
4614                 goto failed_mount6;
4615
4616         err = ext4_register_sysfs(sb);
4617         if (err)
4618                 goto failed_mount7;
4619
4620 #ifdef CONFIG_QUOTA
4621         /* Enable quota usage during mount. */
4622         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4623                 err = ext4_enable_quotas(sb);
4624                 if (err)
4625                         goto failed_mount8;
4626         }
4627 #endif  /* CONFIG_QUOTA */
4628
4629         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4630         ext4_orphan_cleanup(sb, es);
4631         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4632         if (needs_recovery) {
4633                 ext4_msg(sb, KERN_INFO, "recovery complete");
4634                 ext4_mark_recovery_complete(sb, es);
4635         }
4636         if (EXT4_SB(sb)->s_journal) {
4637                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4638                         descr = " journalled data mode";
4639                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4640                         descr = " ordered data mode";
4641                 else
4642                         descr = " writeback data mode";
4643         } else
4644                 descr = "out journal";
4645
4646         if (test_opt(sb, DISCARD)) {
4647                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4648                 if (!blk_queue_discard(q))
4649                         ext4_msg(sb, KERN_WARNING,
4650                                  "mounting with \"discard\" option, but "
4651                                  "the device does not support discard");
4652         }
4653
4654         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4655                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4656                          "Opts: %.*s%s%s", descr,
4657                          (int) sizeof(sbi->s_es->s_mount_opts),
4658                          sbi->s_es->s_mount_opts,
4659                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4660
4661         if (es->s_error_count)
4662                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4663
4664         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4665         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4666         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4667         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4668
4669         kfree(orig_data);
4670         return 0;
4671
4672 cantfind_ext4:
4673         if (!silent)
4674                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4675         goto failed_mount;
4676
4677 #ifdef CONFIG_QUOTA
4678 failed_mount8:
4679         ext4_unregister_sysfs(sb);
4680 #endif
4681 failed_mount7:
4682         ext4_unregister_li_request(sb);
4683 failed_mount6:
4684         ext4_mb_release(sb);
4685         if (sbi->s_flex_groups)
4686                 kvfree(sbi->s_flex_groups);
4687         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4688         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4689         percpu_counter_destroy(&sbi->s_dirs_counter);
4690         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4691         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
4692 failed_mount5:
4693         ext4_ext_release(sb);
4694         ext4_release_system_zone(sb);
4695 failed_mount4a:
4696         dput(sb->s_root);
4697         sb->s_root = NULL;
4698 failed_mount4:
4699         ext4_msg(sb, KERN_ERR, "mount failed");
4700         if (EXT4_SB(sb)->rsv_conversion_wq)
4701                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4702 failed_mount_wq:
4703         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4704         sbi->s_ea_inode_cache = NULL;
4705
4706         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4707         sbi->s_ea_block_cache = NULL;
4708
4709         if (sbi->s_journal) {
4710                 jbd2_journal_destroy(sbi->s_journal);
4711                 sbi->s_journal = NULL;
4712         }
4713 failed_mount3a:
4714         ext4_es_unregister_shrinker(sbi);
4715 failed_mount3:
4716         del_timer_sync(&sbi->s_err_report);
4717         if (sbi->s_mmp_tsk)
4718                 kthread_stop(sbi->s_mmp_tsk);
4719 failed_mount2:
4720         for (i = 0; i < db_count; i++)
4721                 brelse(sbi->s_group_desc[i]);
4722         kvfree(sbi->s_group_desc);
4723 failed_mount:
4724         if (sbi->s_chksum_driver)
4725                 crypto_free_shash(sbi->s_chksum_driver);
4726
4727 #ifdef CONFIG_UNICODE
4728         utf8_unload(sbi->s_encoding);
4729 #endif
4730
4731 #ifdef CONFIG_QUOTA
4732         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4733                 kfree(get_qf_name(sb, sbi, i));
4734 #endif
4735         ext4_blkdev_remove(sbi);
4736         brelse(bh);
4737 out_fail:
4738         sb->s_fs_info = NULL;
4739         kfree(sbi->s_blockgroup_lock);
4740 out_free_base:
4741         kfree(sbi);
4742         kfree(orig_data);
4743         fs_put_dax(dax_dev);
4744         return err ? err : ret;
4745 }
4746
4747 /*
4748  * Setup any per-fs journal parameters now.  We'll do this both on
4749  * initial mount, once the journal has been initialised but before we've
4750  * done any recovery; and again on any subsequent remount.
4751  */
4752 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4753 {
4754         struct ext4_sb_info *sbi = EXT4_SB(sb);
4755
4756         journal->j_commit_interval = sbi->s_commit_interval;
4757         journal->j_min_batch_time = sbi->s_min_batch_time;
4758         journal->j_max_batch_time = sbi->s_max_batch_time;
4759
4760         write_lock(&journal->j_state_lock);
4761         if (test_opt(sb, BARRIER))
4762                 journal->j_flags |= JBD2_BARRIER;
4763         else
4764                 journal->j_flags &= ~JBD2_BARRIER;
4765         if (test_opt(sb, DATA_ERR_ABORT))
4766                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4767         else
4768                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4769         write_unlock(&journal->j_state_lock);
4770 }
4771
4772 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4773                                              unsigned int journal_inum)
4774 {
4775         struct inode *journal_inode;
4776
4777         /*
4778          * Test for the existence of a valid inode on disk.  Bad things
4779          * happen if we iget() an unused inode, as the subsequent iput()
4780          * will try to delete it.
4781          */
4782         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
4783         if (IS_ERR(journal_inode)) {
4784                 ext4_msg(sb, KERN_ERR, "no journal found");
4785                 return NULL;
4786         }
4787         if (!journal_inode->i_nlink) {
4788                 make_bad_inode(journal_inode);
4789                 iput(journal_inode);
4790                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4791                 return NULL;
4792         }
4793
4794         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4795                   journal_inode, journal_inode->i_size);
4796         if (!S_ISREG(journal_inode->i_mode)) {
4797                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4798                 iput(journal_inode);
4799                 return NULL;
4800         }
4801         return journal_inode;
4802 }
4803
4804 static journal_t *ext4_get_journal(struct super_block *sb,
4805                                    unsigned int journal_inum)
4806 {
4807         struct inode *journal_inode;
4808         journal_t *journal;
4809
4810         BUG_ON(!ext4_has_feature_journal(sb));
4811
4812         journal_inode = ext4_get_journal_inode(sb, journal_inum);
4813         if (!journal_inode)
4814                 return NULL;
4815
4816         journal = jbd2_journal_init_inode(journal_inode);
4817         if (!journal) {
4818                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4819                 iput(journal_inode);
4820                 return NULL;
4821         }
4822         journal->j_private = sb;
4823         ext4_init_journal_params(sb, journal);
4824         return journal;
4825 }
4826
4827 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4828                                        dev_t j_dev)
4829 {
4830         struct buffer_head *bh;
4831         journal_t *journal;
4832         ext4_fsblk_t start;
4833         ext4_fsblk_t len;
4834         int hblock, blocksize;
4835         ext4_fsblk_t sb_block;
4836         unsigned long offset;
4837         struct ext4_super_block *es;
4838         struct block_device *bdev;
4839
4840         BUG_ON(!ext4_has_feature_journal(sb));
4841
4842         bdev = ext4_blkdev_get(j_dev, sb);
4843         if (bdev == NULL)
4844                 return NULL;
4845
4846         blocksize = sb->s_blocksize;
4847         hblock = bdev_logical_block_size(bdev);
4848         if (blocksize < hblock) {
4849                 ext4_msg(sb, KERN_ERR,
4850                         "blocksize too small for journal device");
4851                 goto out_bdev;
4852         }
4853
4854         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4855         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4856         set_blocksize(bdev, blocksize);
4857         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4858                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4859                        "external journal");
4860                 goto out_bdev;
4861         }
4862
4863         es = (struct ext4_super_block *) (bh->b_data + offset);
4864         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4865             !(le32_to_cpu(es->s_feature_incompat) &
4866               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4867                 ext4_msg(sb, KERN_ERR, "external journal has "
4868                                         "bad superblock");
4869                 brelse(bh);
4870                 goto out_bdev;
4871         }
4872
4873         if ((le32_to_cpu(es->s_feature_ro_compat) &
4874              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4875             es->s_checksum != ext4_superblock_csum(sb, es)) {
4876                 ext4_msg(sb, KERN_ERR, "external journal has "
4877                                        "corrupt superblock");
4878                 brelse(bh);
4879                 goto out_bdev;
4880         }
4881
4882         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4883                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4884                 brelse(bh);
4885                 goto out_bdev;
4886         }
4887
4888         len = ext4_blocks_count(es);
4889         start = sb_block + 1;
4890         brelse(bh);     /* we're done with the superblock */
4891
4892         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4893                                         start, len, blocksize);
4894         if (!journal) {
4895                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4896                 goto out_bdev;
4897         }
4898         journal->j_private = sb;
4899         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4900         wait_on_buffer(journal->j_sb_buffer);
4901         if (!buffer_uptodate(journal->j_sb_buffer)) {
4902                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4903                 goto out_journal;
4904         }
4905         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4906                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4907                                         "user (unsupported) - %d",
4908                         be32_to_cpu(journal->j_superblock->s_nr_users));
4909                 goto out_journal;
4910         }
4911         EXT4_SB(sb)->journal_bdev = bdev;
4912         ext4_init_journal_params(sb, journal);
4913         return journal;
4914
4915 out_journal:
4916         jbd2_journal_destroy(journal);
4917 out_bdev:
4918         ext4_blkdev_put(bdev);
4919         return NULL;
4920 }
4921
4922 static int ext4_load_journal(struct super_block *sb,
4923                              struct ext4_super_block *es,
4924                              unsigned long journal_devnum)
4925 {
4926         journal_t *journal;
4927         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4928         dev_t journal_dev;
4929         int err = 0;
4930         int really_read_only;
4931
4932         BUG_ON(!ext4_has_feature_journal(sb));
4933
4934         if (journal_devnum &&
4935             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4936                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4937                         "numbers have changed");
4938                 journal_dev = new_decode_dev(journal_devnum);
4939         } else
4940                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4941
4942         really_read_only = bdev_read_only(sb->s_bdev);
4943
4944         /*
4945          * Are we loading a blank journal or performing recovery after a
4946          * crash?  For recovery, we need to check in advance whether we
4947          * can get read-write access to the device.
4948          */
4949         if (ext4_has_feature_journal_needs_recovery(sb)) {
4950                 if (sb_rdonly(sb)) {
4951                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4952                                         "required on readonly filesystem");
4953                         if (really_read_only) {
4954                                 ext4_msg(sb, KERN_ERR, "write access "
4955                                         "unavailable, cannot proceed "
4956                                         "(try mounting with noload)");
4957                                 return -EROFS;
4958                         }
4959                         ext4_msg(sb, KERN_INFO, "write access will "
4960                                "be enabled during recovery");
4961                 }
4962         }
4963
4964         if (journal_inum && journal_dev) {
4965                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4966                        "and inode journals!");
4967                 return -EINVAL;
4968         }
4969
4970         if (journal_inum) {
4971                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4972                         return -EINVAL;
4973         } else {
4974                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4975                         return -EINVAL;
4976         }
4977
4978         if (!(journal->j_flags & JBD2_BARRIER))
4979                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4980
4981         if (!ext4_has_feature_journal_needs_recovery(sb))
4982                 err = jbd2_journal_wipe(journal, !really_read_only);
4983         if (!err) {
4984                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4985                 if (save)
4986                         memcpy(save, ((char *) es) +
4987                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4988                 err = jbd2_journal_load(journal);
4989                 if (save)
4990                         memcpy(((char *) es) + EXT4_S_ERR_START,
4991                                save, EXT4_S_ERR_LEN);
4992                 kfree(save);
4993         }
4994
4995         if (err) {
4996                 ext4_msg(sb, KERN_ERR, "error loading journal");
4997                 jbd2_journal_destroy(journal);
4998                 return err;
4999         }
5000
5001         EXT4_SB(sb)->s_journal = journal;
5002         ext4_clear_journal_err(sb, es);
5003
5004         if (!really_read_only && journal_devnum &&
5005             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5006                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5007
5008                 /* Make sure we flush the recovery flag to disk. */
5009                 ext4_commit_super(sb, 1);
5010         }
5011
5012         return 0;
5013 }
5014
5015 static int ext4_commit_super(struct super_block *sb, int sync)
5016 {
5017         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
5018         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5019         int error = 0;
5020
5021         if (!sbh || block_device_ejected(sb))
5022                 return error;
5023
5024         /*
5025          * The superblock bh should be mapped, but it might not be if the
5026          * device was hot-removed. Not much we can do but fail the I/O.
5027          */
5028         if (!buffer_mapped(sbh))
5029                 return error;
5030
5031         /*
5032          * If the file system is mounted read-only, don't update the
5033          * superblock write time.  This avoids updating the superblock
5034          * write time when we are mounting the root file system
5035          * read/only but we need to replay the journal; at that point,
5036          * for people who are east of GMT and who make their clock
5037          * tick in localtime for Windows bug-for-bug compatibility,
5038          * the clock is set in the future, and this will cause e2fsck
5039          * to complain and force a full file system check.
5040          */
5041         if (!(sb->s_flags & SB_RDONLY))
5042                 ext4_update_tstamp(es, s_wtime);
5043         if (sb->s_bdev->bd_part)
5044                 es->s_kbytes_written =
5045                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5046                             ((part_stat_read(sb->s_bdev->bd_part,
5047                                              sectors[STAT_WRITE]) -
5048                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
5049         else
5050                 es->s_kbytes_written =
5051                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5052         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5053                 ext4_free_blocks_count_set(es,
5054                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5055                                 &EXT4_SB(sb)->s_freeclusters_counter)));
5056         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5057                 es->s_free_inodes_count =
5058                         cpu_to_le32(percpu_counter_sum_positive(
5059                                 &EXT4_SB(sb)->s_freeinodes_counter));
5060         BUFFER_TRACE(sbh, "marking dirty");
5061         ext4_superblock_csum_set(sb);
5062         if (sync)
5063                 lock_buffer(sbh);
5064         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5065                 /*
5066                  * Oh, dear.  A previous attempt to write the
5067                  * superblock failed.  This could happen because the
5068                  * USB device was yanked out.  Or it could happen to
5069                  * be a transient write error and maybe the block will
5070                  * be remapped.  Nothing we can do but to retry the
5071                  * write and hope for the best.
5072                  */
5073                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5074                        "superblock detected");
5075                 clear_buffer_write_io_error(sbh);
5076                 set_buffer_uptodate(sbh);
5077         }
5078         mark_buffer_dirty(sbh);
5079         if (sync) {
5080                 unlock_buffer(sbh);
5081                 error = __sync_dirty_buffer(sbh,
5082                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5083                 if (buffer_write_io_error(sbh)) {
5084                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5085                                "superblock");
5086                         clear_buffer_write_io_error(sbh);
5087                         set_buffer_uptodate(sbh);
5088                 }
5089         }
5090         return error;
5091 }
5092
5093 /*
5094  * Have we just finished recovery?  If so, and if we are mounting (or
5095  * remounting) the filesystem readonly, then we will end up with a
5096  * consistent fs on disk.  Record that fact.
5097  */
5098 static void ext4_mark_recovery_complete(struct super_block *sb,
5099                                         struct ext4_super_block *es)
5100 {
5101         journal_t *journal = EXT4_SB(sb)->s_journal;
5102
5103         if (!ext4_has_feature_journal(sb)) {
5104                 BUG_ON(journal != NULL);
5105                 return;
5106         }
5107         jbd2_journal_lock_updates(journal);
5108         if (jbd2_journal_flush(journal) < 0)
5109                 goto out;
5110
5111         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5112                 ext4_clear_feature_journal_needs_recovery(sb);
5113                 ext4_commit_super(sb, 1);
5114         }
5115
5116 out:
5117         jbd2_journal_unlock_updates(journal);
5118 }
5119
5120 /*
5121  * If we are mounting (or read-write remounting) a filesystem whose journal
5122  * has recorded an error from a previous lifetime, move that error to the
5123  * main filesystem now.
5124  */
5125 static void ext4_clear_journal_err(struct super_block *sb,
5126                                    struct ext4_super_block *es)
5127 {
5128         journal_t *journal;
5129         int j_errno;
5130         const char *errstr;
5131
5132         BUG_ON(!ext4_has_feature_journal(sb));
5133
5134         journal = EXT4_SB(sb)->s_journal;
5135
5136         /*
5137          * Now check for any error status which may have been recorded in the
5138          * journal by a prior ext4_error() or ext4_abort()
5139          */
5140
5141         j_errno = jbd2_journal_errno(journal);
5142         if (j_errno) {
5143                 char nbuf[16];
5144
5145                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5146                 ext4_warning(sb, "Filesystem error recorded "
5147                              "from previous mount: %s", errstr);
5148                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5149
5150                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5151                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5152                 ext4_commit_super(sb, 1);
5153
5154                 jbd2_journal_clear_err(journal);
5155                 jbd2_journal_update_sb_errno(journal);
5156         }
5157 }
5158
5159 /*
5160  * Force the running and committing transactions to commit,
5161  * and wait on the commit.
5162  */
5163 int ext4_force_commit(struct super_block *sb)
5164 {
5165         journal_t *journal;
5166
5167         if (sb_rdonly(sb))
5168                 return 0;
5169
5170         journal = EXT4_SB(sb)->s_journal;
5171         return ext4_journal_force_commit(journal);
5172 }
5173
5174 static int ext4_sync_fs(struct super_block *sb, int wait)
5175 {
5176         int ret = 0;
5177         tid_t target;
5178         bool needs_barrier = false;
5179         struct ext4_sb_info *sbi = EXT4_SB(sb);
5180
5181         if (unlikely(ext4_forced_shutdown(sbi)))
5182                 return 0;
5183
5184         trace_ext4_sync_fs(sb, wait);
5185         flush_workqueue(sbi->rsv_conversion_wq);
5186         /*
5187          * Writeback quota in non-journalled quota case - journalled quota has
5188          * no dirty dquots
5189          */
5190         dquot_writeback_dquots(sb, -1);
5191         /*
5192          * Data writeback is possible w/o journal transaction, so barrier must
5193          * being sent at the end of the function. But we can skip it if
5194          * transaction_commit will do it for us.
5195          */
5196         if (sbi->s_journal) {
5197                 target = jbd2_get_latest_transaction(sbi->s_journal);
5198                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5199                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5200                         needs_barrier = true;
5201
5202                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5203                         if (wait)
5204                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5205                                                            target);
5206                 }
5207         } else if (wait && test_opt(sb, BARRIER))
5208                 needs_barrier = true;
5209         if (needs_barrier) {
5210                 int err;
5211                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
5212                 if (!ret)
5213                         ret = err;
5214         }
5215
5216         return ret;
5217 }
5218
5219 /*
5220  * LVM calls this function before a (read-only) snapshot is created.  This
5221  * gives us a chance to flush the journal completely and mark the fs clean.
5222  *
5223  * Note that only this function cannot bring a filesystem to be in a clean
5224  * state independently. It relies on upper layer to stop all data & metadata
5225  * modifications.
5226  */
5227 static int ext4_freeze(struct super_block *sb)
5228 {
5229         int error = 0;
5230         journal_t *journal;
5231
5232         if (sb_rdonly(sb))
5233                 return 0;
5234
5235         journal = EXT4_SB(sb)->s_journal;
5236
5237         if (journal) {
5238                 /* Now we set up the journal barrier. */
5239                 jbd2_journal_lock_updates(journal);
5240
5241                 /*
5242                  * Don't clear the needs_recovery flag if we failed to
5243                  * flush the journal.
5244                  */
5245                 error = jbd2_journal_flush(journal);
5246                 if (error < 0)
5247                         goto out;
5248
5249                 /* Journal blocked and flushed, clear needs_recovery flag. */
5250                 ext4_clear_feature_journal_needs_recovery(sb);
5251         }
5252
5253         error = ext4_commit_super(sb, 1);
5254 out:
5255         if (journal)
5256                 /* we rely on upper layer to stop further updates */
5257                 jbd2_journal_unlock_updates(journal);
5258         return error;
5259 }
5260
5261 /*
5262  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5263  * flag here, even though the filesystem is not technically dirty yet.
5264  */
5265 static int ext4_unfreeze(struct super_block *sb)
5266 {
5267         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5268                 return 0;
5269
5270         if (EXT4_SB(sb)->s_journal) {
5271                 /* Reset the needs_recovery flag before the fs is unlocked. */
5272                 ext4_set_feature_journal_needs_recovery(sb);
5273         }
5274
5275         ext4_commit_super(sb, 1);
5276         return 0;
5277 }
5278
5279 /*
5280  * Structure to save mount options for ext4_remount's benefit
5281  */
5282 struct ext4_mount_options {
5283         unsigned long s_mount_opt;
5284         unsigned long s_mount_opt2;
5285         kuid_t s_resuid;
5286         kgid_t s_resgid;
5287         unsigned long s_commit_interval;
5288         u32 s_min_batch_time, s_max_batch_time;
5289 #ifdef CONFIG_QUOTA
5290         int s_jquota_fmt;
5291         char *s_qf_names[EXT4_MAXQUOTAS];
5292 #endif
5293 };
5294
5295 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5296 {
5297         struct ext4_super_block *es;
5298         struct ext4_sb_info *sbi = EXT4_SB(sb);
5299         unsigned long old_sb_flags;
5300         struct ext4_mount_options old_opts;
5301         int enable_quota = 0;
5302         ext4_group_t g;
5303         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5304         int err = 0;
5305 #ifdef CONFIG_QUOTA
5306         int i, j;
5307         char *to_free[EXT4_MAXQUOTAS];
5308 #endif
5309         char *orig_data = kstrdup(data, GFP_KERNEL);
5310
5311         if (data && !orig_data)
5312                 return -ENOMEM;
5313
5314         /* Store the original options */
5315         old_sb_flags = sb->s_flags;
5316         old_opts.s_mount_opt = sbi->s_mount_opt;
5317         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5318         old_opts.s_resuid = sbi->s_resuid;
5319         old_opts.s_resgid = sbi->s_resgid;
5320         old_opts.s_commit_interval = sbi->s_commit_interval;
5321         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5322         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5323 #ifdef CONFIG_QUOTA
5324         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5325         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5326                 if (sbi->s_qf_names[i]) {
5327                         char *qf_name = get_qf_name(sb, sbi, i);
5328
5329                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5330                         if (!old_opts.s_qf_names[i]) {
5331                                 for (j = 0; j < i; j++)
5332                                         kfree(old_opts.s_qf_names[j]);
5333                                 kfree(orig_data);
5334                                 return -ENOMEM;
5335                         }
5336                 } else
5337                         old_opts.s_qf_names[i] = NULL;
5338 #endif
5339         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5340                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5341
5342         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5343                 err = -EINVAL;
5344                 goto restore_opts;
5345         }
5346
5347         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5348             test_opt(sb, JOURNAL_CHECKSUM)) {
5349                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5350                          "during remount not supported; ignoring");
5351                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5352         }
5353
5354         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5355                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5356                         ext4_msg(sb, KERN_ERR, "can't mount with "
5357                                  "both data=journal and delalloc");
5358                         err = -EINVAL;
5359                         goto restore_opts;
5360                 }
5361                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5362                         ext4_msg(sb, KERN_ERR, "can't mount with "
5363                                  "both data=journal and dioread_nolock");
5364                         err = -EINVAL;
5365                         goto restore_opts;
5366                 }
5367                 if (test_opt(sb, DAX)) {
5368                         ext4_msg(sb, KERN_ERR, "can't mount with "
5369                                  "both data=journal and dax");
5370                         err = -EINVAL;
5371                         goto restore_opts;
5372                 }
5373         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5374                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5375                         ext4_msg(sb, KERN_ERR, "can't mount with "
5376                                 "journal_async_commit in data=ordered mode");
5377                         err = -EINVAL;
5378                         goto restore_opts;
5379                 }
5380         }
5381
5382         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5383                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5384                 err = -EINVAL;
5385                 goto restore_opts;
5386         }
5387
5388         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
5389                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
5390                         "dax flag with busy inodes while remounting");
5391                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
5392         }
5393
5394         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5395                 ext4_abort(sb, "Abort forced by user");
5396
5397         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5398                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5399
5400         es = sbi->s_es;
5401
5402         if (sbi->s_journal) {
5403                 ext4_init_journal_params(sb, sbi->s_journal);
5404                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5405         }
5406
5407         if (*flags & SB_LAZYTIME)
5408                 sb->s_flags |= SB_LAZYTIME;
5409
5410         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5411                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5412                         err = -EROFS;
5413                         goto restore_opts;
5414                 }
5415
5416                 if (*flags & SB_RDONLY) {
5417                         err = sync_filesystem(sb);
5418                         if (err < 0)
5419                                 goto restore_opts;
5420                         err = dquot_suspend(sb, -1);
5421                         if (err < 0)
5422                                 goto restore_opts;
5423
5424                         /*
5425                          * First of all, the unconditional stuff we have to do
5426                          * to disable replay of the journal when we next remount
5427                          */
5428                         sb->s_flags |= SB_RDONLY;
5429
5430                         /*
5431                          * OK, test if we are remounting a valid rw partition
5432                          * readonly, and if so set the rdonly flag and then
5433                          * mark the partition as valid again.
5434                          */
5435                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5436                             (sbi->s_mount_state & EXT4_VALID_FS))
5437                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5438
5439                         if (sbi->s_journal)
5440                                 ext4_mark_recovery_complete(sb, es);
5441                         if (sbi->s_mmp_tsk)
5442                                 kthread_stop(sbi->s_mmp_tsk);
5443                 } else {
5444                         /* Make sure we can mount this feature set readwrite */
5445                         if (ext4_has_feature_readonly(sb) ||
5446                             !ext4_feature_set_ok(sb, 0)) {
5447                                 err = -EROFS;
5448                                 goto restore_opts;
5449                         }
5450                         /*
5451                          * Make sure the group descriptor checksums
5452                          * are sane.  If they aren't, refuse to remount r/w.
5453                          */
5454                         for (g = 0; g < sbi->s_groups_count; g++) {
5455                                 struct ext4_group_desc *gdp =
5456                                         ext4_get_group_desc(sb, g, NULL);
5457
5458                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5459                                         ext4_msg(sb, KERN_ERR,
5460                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5461                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5462                                                le16_to_cpu(gdp->bg_checksum));
5463                                         err = -EFSBADCRC;
5464                                         goto restore_opts;
5465                                 }
5466                         }
5467
5468                         /*
5469                          * If we have an unprocessed orphan list hanging
5470                          * around from a previously readonly bdev mount,
5471                          * require a full umount/remount for now.
5472                          */
5473                         if (es->s_last_orphan) {
5474                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5475                                        "remount RDWR because of unprocessed "
5476                                        "orphan inode list.  Please "
5477                                        "umount/remount instead");
5478                                 err = -EINVAL;
5479                                 goto restore_opts;
5480                         }
5481
5482                         /*
5483                          * Mounting a RDONLY partition read-write, so reread
5484                          * and store the current valid flag.  (It may have
5485                          * been changed by e2fsck since we originally mounted
5486                          * the partition.)
5487                          */
5488                         if (sbi->s_journal)
5489                                 ext4_clear_journal_err(sb, es);
5490                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5491
5492                         err = ext4_setup_super(sb, es, 0);
5493                         if (err)
5494                                 goto restore_opts;
5495
5496                         sb->s_flags &= ~SB_RDONLY;
5497                         if (ext4_has_feature_mmp(sb))
5498                                 if (ext4_multi_mount_protect(sb,
5499                                                 le64_to_cpu(es->s_mmp_block))) {
5500                                         err = -EROFS;
5501                                         goto restore_opts;
5502                                 }
5503                         enable_quota = 1;
5504                 }
5505         }
5506
5507         /*
5508          * Reinitialize lazy itable initialization thread based on
5509          * current settings
5510          */
5511         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5512                 ext4_unregister_li_request(sb);
5513         else {
5514                 ext4_group_t first_not_zeroed;
5515                 first_not_zeroed = ext4_has_uninit_itable(sb);
5516                 ext4_register_li_request(sb, first_not_zeroed);
5517         }
5518
5519         ext4_setup_system_zone(sb);
5520         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5521                 err = ext4_commit_super(sb, 1);
5522                 if (err)
5523                         goto restore_opts;
5524         }
5525
5526 #ifdef CONFIG_QUOTA
5527         /* Release old quota file names */
5528         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5529                 kfree(old_opts.s_qf_names[i]);
5530         if (enable_quota) {
5531                 if (sb_any_quota_suspended(sb))
5532                         dquot_resume(sb, -1);
5533                 else if (ext4_has_feature_quota(sb)) {
5534                         err = ext4_enable_quotas(sb);
5535                         if (err)
5536                                 goto restore_opts;
5537                 }
5538         }
5539 #endif
5540
5541         *flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME);
5542         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5543         kfree(orig_data);
5544         return 0;
5545
5546 restore_opts:
5547         sb->s_flags = old_sb_flags;
5548         sbi->s_mount_opt = old_opts.s_mount_opt;
5549         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5550         sbi->s_resuid = old_opts.s_resuid;
5551         sbi->s_resgid = old_opts.s_resgid;
5552         sbi->s_commit_interval = old_opts.s_commit_interval;
5553         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5554         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5555 #ifdef CONFIG_QUOTA
5556         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5557         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5558                 to_free[i] = get_qf_name(sb, sbi, i);
5559                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
5560         }
5561         synchronize_rcu();
5562         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5563                 kfree(to_free[i]);
5564 #endif
5565         kfree(orig_data);
5566         return err;
5567 }
5568
5569 #ifdef CONFIG_QUOTA
5570 static int ext4_statfs_project(struct super_block *sb,
5571                                kprojid_t projid, struct kstatfs *buf)
5572 {
5573         struct kqid qid;
5574         struct dquot *dquot;
5575         u64 limit;
5576         u64 curblock;
5577
5578         qid = make_kqid_projid(projid);
5579         dquot = dqget(sb, qid);
5580         if (IS_ERR(dquot))
5581                 return PTR_ERR(dquot);
5582         spin_lock(&dquot->dq_dqb_lock);
5583
5584         limit = dquot->dq_dqb.dqb_bsoftlimit;
5585         if (dquot->dq_dqb.dqb_bhardlimit &&
5586             (!limit || dquot->dq_dqb.dqb_bhardlimit < limit))
5587                 limit = dquot->dq_dqb.dqb_bhardlimit;
5588         limit >>= sb->s_blocksize_bits;
5589
5590         if (limit && buf->f_blocks > limit) {
5591                 curblock = (dquot->dq_dqb.dqb_curspace +
5592                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5593                 buf->f_blocks = limit;
5594                 buf->f_bfree = buf->f_bavail =
5595                         (buf->f_blocks > curblock) ?
5596                          (buf->f_blocks - curblock) : 0;
5597         }
5598
5599         limit = dquot->dq_dqb.dqb_isoftlimit;
5600         if (dquot->dq_dqb.dqb_ihardlimit &&
5601             (!limit || dquot->dq_dqb.dqb_ihardlimit < limit))
5602                 limit = dquot->dq_dqb.dqb_ihardlimit;
5603
5604         if (limit && buf->f_files > limit) {
5605                 buf->f_files = limit;
5606                 buf->f_ffree =
5607                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5608                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5609         }
5610
5611         spin_unlock(&dquot->dq_dqb_lock);
5612         dqput(dquot);
5613         return 0;
5614 }
5615 #endif
5616
5617 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5618 {
5619         struct super_block *sb = dentry->d_sb;
5620         struct ext4_sb_info *sbi = EXT4_SB(sb);
5621         struct ext4_super_block *es = sbi->s_es;
5622         ext4_fsblk_t overhead = 0, resv_blocks;
5623         u64 fsid;
5624         s64 bfree;
5625         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5626
5627         if (!test_opt(sb, MINIX_DF))
5628                 overhead = sbi->s_overhead;
5629
5630         buf->f_type = EXT4_SUPER_MAGIC;
5631         buf->f_bsize = sb->s_blocksize;
5632         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5633         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5634                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5635         /* prevent underflow in case that few free space is available */
5636         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5637         buf->f_bavail = buf->f_bfree -
5638                         (ext4_r_blocks_count(es) + resv_blocks);
5639         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5640                 buf->f_bavail = 0;
5641         buf->f_files = le32_to_cpu(es->s_inodes_count);
5642         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5643         buf->f_namelen = EXT4_NAME_LEN;
5644         fsid = le64_to_cpup((void *)es->s_uuid) ^
5645                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5646         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5647         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5648
5649 #ifdef CONFIG_QUOTA
5650         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5651             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5652                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5653 #endif
5654         return 0;
5655 }
5656
5657
5658 #ifdef CONFIG_QUOTA
5659
5660 /*
5661  * Helper functions so that transaction is started before we acquire dqio_sem
5662  * to keep correct lock ordering of transaction > dqio_sem
5663  */
5664 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5665 {
5666         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5667 }
5668
5669 static int ext4_write_dquot(struct dquot *dquot)
5670 {
5671         int ret, err;
5672         handle_t *handle;
5673         struct inode *inode;
5674
5675         inode = dquot_to_inode(dquot);
5676         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5677                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5678         if (IS_ERR(handle))
5679                 return PTR_ERR(handle);
5680         ret = dquot_commit(dquot);
5681         err = ext4_journal_stop(handle);
5682         if (!ret)
5683                 ret = err;
5684         return ret;
5685 }
5686
5687 static int ext4_acquire_dquot(struct dquot *dquot)
5688 {
5689         int ret, err;
5690         handle_t *handle;
5691
5692         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5693                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5694         if (IS_ERR(handle))
5695                 return PTR_ERR(handle);
5696         ret = dquot_acquire(dquot);
5697         err = ext4_journal_stop(handle);
5698         if (!ret)
5699                 ret = err;
5700         return ret;
5701 }
5702
5703 static int ext4_release_dquot(struct dquot *dquot)
5704 {
5705         int ret, err;
5706         handle_t *handle;
5707
5708         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5709                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5710         if (IS_ERR(handle)) {
5711                 /* Release dquot anyway to avoid endless cycle in dqput() */
5712                 dquot_release(dquot);
5713                 return PTR_ERR(handle);
5714         }
5715         ret = dquot_release(dquot);
5716         err = ext4_journal_stop(handle);
5717         if (!ret)
5718                 ret = err;
5719         return ret;
5720 }
5721
5722 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5723 {
5724         struct super_block *sb = dquot->dq_sb;
5725         struct ext4_sb_info *sbi = EXT4_SB(sb);
5726
5727         /* Are we journaling quotas? */
5728         if (ext4_has_feature_quota(sb) ||
5729             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5730                 dquot_mark_dquot_dirty(dquot);
5731                 return ext4_write_dquot(dquot);
5732         } else {
5733                 return dquot_mark_dquot_dirty(dquot);
5734         }
5735 }
5736
5737 static int ext4_write_info(struct super_block *sb, int type)
5738 {
5739         int ret, err;
5740         handle_t *handle;
5741
5742         /* Data block + inode block */
5743         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5744         if (IS_ERR(handle))
5745                 return PTR_ERR(handle);
5746         ret = dquot_commit_info(sb, type);
5747         err = ext4_journal_stop(handle);
5748         if (!ret)
5749                 ret = err;
5750         return ret;
5751 }
5752
5753 /*
5754  * Turn on quotas during mount time - we need to find
5755  * the quota file and such...
5756  */
5757 static int ext4_quota_on_mount(struct super_block *sb, int type)
5758 {
5759         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
5760                                         EXT4_SB(sb)->s_jquota_fmt, type);
5761 }
5762
5763 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5764 {
5765         struct ext4_inode_info *ei = EXT4_I(inode);
5766
5767         /* The first argument of lockdep_set_subclass has to be
5768          * *exactly* the same as the argument to init_rwsem() --- in
5769          * this case, in init_once() --- or lockdep gets unhappy
5770          * because the name of the lock is set using the
5771          * stringification of the argument to init_rwsem().
5772          */
5773         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
5774         lockdep_set_subclass(&ei->i_data_sem, subclass);
5775 }
5776
5777 /*
5778  * Standard function to be called on quota_on
5779  */
5780 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5781                          const struct path *path)
5782 {
5783         int err;
5784
5785         if (!test_opt(sb, QUOTA))
5786                 return -EINVAL;
5787
5788         /* Quotafile not on the same filesystem? */
5789         if (path->dentry->d_sb != sb)
5790                 return -EXDEV;
5791         /* Journaling quota? */
5792         if (EXT4_SB(sb)->s_qf_names[type]) {
5793                 /* Quotafile not in fs root? */
5794                 if (path->dentry->d_parent != sb->s_root)
5795                         ext4_msg(sb, KERN_WARNING,
5796                                 "Quota file not on filesystem root. "
5797                                 "Journaled quota will not work");
5798                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5799         } else {
5800                 /*
5801                  * Clear the flag just in case mount options changed since
5802                  * last time.
5803                  */
5804                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5805         }
5806
5807         /*
5808          * When we journal data on quota file, we have to flush journal to see
5809          * all updates to the file when we bypass pagecache...
5810          */
5811         if (EXT4_SB(sb)->s_journal &&
5812             ext4_should_journal_data(d_inode(path->dentry))) {
5813                 /*
5814                  * We don't need to lock updates but journal_flush() could
5815                  * otherwise be livelocked...
5816                  */
5817                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5818                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5819                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5820                 if (err)
5821                         return err;
5822         }
5823
5824         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5825         err = dquot_quota_on(sb, type, format_id, path);
5826         if (err) {
5827                 lockdep_set_quota_inode(path->dentry->d_inode,
5828                                              I_DATA_SEM_NORMAL);
5829         } else {
5830                 struct inode *inode = d_inode(path->dentry);
5831                 handle_t *handle;
5832
5833                 /*
5834                  * Set inode flags to prevent userspace from messing with quota
5835                  * files. If this fails, we return success anyway since quotas
5836                  * are already enabled and this is not a hard failure.
5837                  */
5838                 inode_lock(inode);
5839                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5840                 if (IS_ERR(handle))
5841                         goto unlock_inode;
5842                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5843                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5844                                 S_NOATIME | S_IMMUTABLE);
5845                 ext4_mark_inode_dirty(handle, inode);
5846                 ext4_journal_stop(handle);
5847         unlock_inode:
5848                 inode_unlock(inode);
5849         }
5850         return err;
5851 }
5852
5853 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5854                              unsigned int flags)
5855 {
5856         int err;
5857         struct inode *qf_inode;
5858         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5859                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5860                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5861                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5862         };
5863
5864         BUG_ON(!ext4_has_feature_quota(sb));
5865
5866         if (!qf_inums[type])
5867                 return -EPERM;
5868
5869         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
5870         if (IS_ERR(qf_inode)) {
5871                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5872                 return PTR_ERR(qf_inode);
5873         }
5874
5875         /* Don't account quota for quota files to avoid recursion */
5876         qf_inode->i_flags |= S_NOQUOTA;
5877         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5878         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
5879         if (err)
5880                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5881         iput(qf_inode);
5882
5883         return err;
5884 }
5885
5886 /* Enable usage tracking for all quota types. */
5887 static int ext4_enable_quotas(struct super_block *sb)
5888 {
5889         int type, err = 0;
5890         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5891                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5892                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5893                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5894         };
5895         bool quota_mopt[EXT4_MAXQUOTAS] = {
5896                 test_opt(sb, USRQUOTA),
5897                 test_opt(sb, GRPQUOTA),
5898                 test_opt(sb, PRJQUOTA),
5899         };
5900
5901         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
5902         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5903                 if (qf_inums[type]) {
5904                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5905                                 DQUOT_USAGE_ENABLED |
5906                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5907                         if (err) {
5908                                 ext4_warning(sb,
5909                                         "Failed to enable quota tracking "
5910                                         "(type=%d, err=%d). Please run "
5911                                         "e2fsck to fix.", type, err);
5912                                 for (type--; type >= 0; type--)
5913                                         dquot_quota_off(sb, type);
5914
5915                                 return err;
5916                         }
5917                 }
5918         }
5919         return 0;
5920 }
5921
5922 static int ext4_quota_off(struct super_block *sb, int type)
5923 {
5924         struct inode *inode = sb_dqopt(sb)->files[type];
5925         handle_t *handle;
5926         int err;
5927
5928         /* Force all delayed allocation blocks to be allocated.
5929          * Caller already holds s_umount sem */
5930         if (test_opt(sb, DELALLOC))
5931                 sync_filesystem(sb);
5932
5933         if (!inode || !igrab(inode))
5934                 goto out;
5935
5936         err = dquot_quota_off(sb, type);
5937         if (err || ext4_has_feature_quota(sb))
5938                 goto out_put;
5939
5940         inode_lock(inode);
5941         /*
5942          * Update modification times of quota files when userspace can
5943          * start looking at them. If we fail, we return success anyway since
5944          * this is not a hard failure and quotas are already disabled.
5945          */
5946         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5947         if (IS_ERR(handle))
5948                 goto out_unlock;
5949         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
5950         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
5951         inode->i_mtime = inode->i_ctime = current_time(inode);
5952         ext4_mark_inode_dirty(handle, inode);
5953         ext4_journal_stop(handle);
5954 out_unlock:
5955         inode_unlock(inode);
5956 out_put:
5957         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
5958         iput(inode);
5959         return err;
5960 out:
5961         return dquot_quota_off(sb, type);
5962 }
5963
5964 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5965  * acquiring the locks... As quota files are never truncated and quota code
5966  * itself serializes the operations (and no one else should touch the files)
5967  * we don't have to be afraid of races */
5968 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5969                                size_t len, loff_t off)
5970 {
5971         struct inode *inode = sb_dqopt(sb)->files[type];
5972         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5973         int offset = off & (sb->s_blocksize - 1);
5974         int tocopy;
5975         size_t toread;
5976         struct buffer_head *bh;
5977         loff_t i_size = i_size_read(inode);
5978
5979         if (off > i_size)
5980                 return 0;
5981         if (off+len > i_size)
5982                 len = i_size-off;
5983         toread = len;
5984         while (toread > 0) {
5985                 tocopy = sb->s_blocksize - offset < toread ?
5986                                 sb->s_blocksize - offset : toread;
5987                 bh = ext4_bread(NULL, inode, blk, 0);
5988                 if (IS_ERR(bh))
5989                         return PTR_ERR(bh);
5990                 if (!bh)        /* A hole? */
5991                         memset(data, 0, tocopy);
5992                 else
5993                         memcpy(data, bh->b_data+offset, tocopy);
5994                 brelse(bh);
5995                 offset = 0;
5996                 toread -= tocopy;
5997                 data += tocopy;
5998                 blk++;
5999         }
6000         return len;
6001 }
6002
6003 /* Write to quotafile (we know the transaction is already started and has
6004  * enough credits) */
6005 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6006                                 const char *data, size_t len, loff_t off)
6007 {
6008         struct inode *inode = sb_dqopt(sb)->files[type];
6009         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6010         int err, offset = off & (sb->s_blocksize - 1);
6011         int retries = 0;
6012         struct buffer_head *bh;
6013         handle_t *handle = journal_current_handle();
6014
6015         if (EXT4_SB(sb)->s_journal && !handle) {
6016                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6017                         " cancelled because transaction is not started",
6018                         (unsigned long long)off, (unsigned long long)len);
6019                 return -EIO;
6020         }
6021         /*
6022          * Since we account only one data block in transaction credits,
6023          * then it is impossible to cross a block boundary.
6024          */
6025         if (sb->s_blocksize - offset < len) {
6026                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6027                         " cancelled because not block aligned",
6028                         (unsigned long long)off, (unsigned long long)len);
6029                 return -EIO;
6030         }
6031
6032         do {
6033                 bh = ext4_bread(handle, inode, blk,
6034                                 EXT4_GET_BLOCKS_CREATE |
6035                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6036         } while (PTR_ERR(bh) == -ENOSPC &&
6037                  ext4_should_retry_alloc(inode->i_sb, &retries));
6038         if (IS_ERR(bh))
6039                 return PTR_ERR(bh);
6040         if (!bh)
6041                 goto out;
6042         BUFFER_TRACE(bh, "get write access");
6043         err = ext4_journal_get_write_access(handle, bh);
6044         if (err) {
6045                 brelse(bh);
6046                 return err;
6047         }
6048         lock_buffer(bh);
6049         memcpy(bh->b_data+offset, data, len);
6050         flush_dcache_page(bh->b_page);
6051         unlock_buffer(bh);
6052         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6053         brelse(bh);
6054 out:
6055         if (inode->i_size < off + len) {
6056                 i_size_write(inode, off + len);
6057                 EXT4_I(inode)->i_disksize = inode->i_size;
6058                 ext4_mark_inode_dirty(handle, inode);
6059         }
6060         return len;
6061 }
6062 #endif
6063
6064 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6065                        const char *dev_name, void *data)
6066 {
6067         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6068 }
6069
6070 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6071 static inline void register_as_ext2(void)
6072 {
6073         int err = register_filesystem(&ext2_fs_type);
6074         if (err)
6075                 printk(KERN_WARNING
6076                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6077 }
6078
6079 static inline void unregister_as_ext2(void)
6080 {
6081         unregister_filesystem(&ext2_fs_type);
6082 }
6083
6084 static inline int ext2_feature_set_ok(struct super_block *sb)
6085 {
6086         if (ext4_has_unknown_ext2_incompat_features(sb))
6087                 return 0;
6088         if (sb_rdonly(sb))
6089                 return 1;
6090         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6091                 return 0;
6092         return 1;
6093 }
6094 #else
6095 static inline void register_as_ext2(void) { }
6096 static inline void unregister_as_ext2(void) { }
6097 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6098 #endif
6099
6100 static inline void register_as_ext3(void)
6101 {
6102         int err = register_filesystem(&ext3_fs_type);
6103         if (err)
6104                 printk(KERN_WARNING
6105                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6106 }
6107
6108 static inline void unregister_as_ext3(void)
6109 {
6110         unregister_filesystem(&ext3_fs_type);
6111 }
6112
6113 static inline int ext3_feature_set_ok(struct super_block *sb)
6114 {
6115         if (ext4_has_unknown_ext3_incompat_features(sb))
6116                 return 0;
6117         if (!ext4_has_feature_journal(sb))
6118                 return 0;
6119         if (sb_rdonly(sb))
6120                 return 1;
6121         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6122                 return 0;
6123         return 1;
6124 }
6125
6126 static struct file_system_type ext4_fs_type = {
6127         .owner          = THIS_MODULE,
6128         .name           = "ext4",
6129         .mount          = ext4_mount,
6130         .kill_sb        = kill_block_super,
6131         .fs_flags       = FS_REQUIRES_DEV,
6132 };
6133 MODULE_ALIAS_FS("ext4");
6134
6135 /* Shared across all ext4 file systems */
6136 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6137
6138 static int __init ext4_init_fs(void)
6139 {
6140         int i, err;
6141
6142         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6143         ext4_li_info = NULL;
6144         mutex_init(&ext4_li_mtx);
6145
6146         /* Build-time check for flags consistency */
6147         ext4_check_flag_values();
6148
6149         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6150                 init_waitqueue_head(&ext4__ioend_wq[i]);
6151
6152         err = ext4_init_es();
6153         if (err)
6154                 return err;
6155
6156         err = ext4_init_pending();
6157         if (err)
6158                 goto out7;
6159
6160         err = ext4_init_post_read_processing();
6161         if (err)
6162                 goto out6;
6163
6164         err = ext4_init_pageio();
6165         if (err)
6166                 goto out5;
6167
6168         err = ext4_init_system_zone();
6169         if (err)
6170                 goto out4;
6171
6172         err = ext4_init_sysfs();
6173         if (err)
6174                 goto out3;
6175
6176         err = ext4_init_mballoc();
6177         if (err)
6178                 goto out2;
6179         err = init_inodecache();
6180         if (err)
6181                 goto out1;
6182         register_as_ext3();
6183         register_as_ext2();
6184         err = register_filesystem(&ext4_fs_type);
6185         if (err)
6186                 goto out;
6187
6188         return 0;
6189 out:
6190         unregister_as_ext2();
6191         unregister_as_ext3();
6192         destroy_inodecache();
6193 out1:
6194         ext4_exit_mballoc();
6195 out2:
6196         ext4_exit_sysfs();
6197 out3:
6198         ext4_exit_system_zone();
6199 out4:
6200         ext4_exit_pageio();
6201 out5:
6202         ext4_exit_post_read_processing();
6203 out6:
6204         ext4_exit_pending();
6205 out7:
6206         ext4_exit_es();
6207
6208         return err;
6209 }
6210
6211 static void __exit ext4_exit_fs(void)
6212 {
6213         ext4_destroy_lazyinit_thread();
6214         unregister_as_ext2();
6215         unregister_as_ext3();
6216         unregister_filesystem(&ext4_fs_type);
6217         destroy_inodecache();
6218         ext4_exit_mballoc();
6219         ext4_exit_sysfs();
6220         ext4_exit_system_zone();
6221         ext4_exit_pageio();
6222         ext4_exit_post_read_processing();
6223         ext4_exit_es();
6224         ext4_exit_pending();
6225 }
6226
6227 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6228 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6229 MODULE_LICENSE("GPL");
6230 MODULE_SOFTDEP("pre: crc32c");
6231 module_init(ext4_init_fs)
6232 module_exit(ext4_exit_fs)