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 #include <linux/part_stat.h>
  47 #include <linux/kthread.h>
  48 #include <linux/freezer.h>
  49
  50 #include "ext4.h"
  51 #include "ext4_extents.h"       /* Needed for trace points definition */
  52 #include "ext4_jbd2.h"
  53 #include "xattr.h"
  54 #include "acl.h"
  55 #include "mballoc.h"
  56 #include "fsmap.h"
  57
  58 #define CREATE_TRACE_POINTS
  59 #include <trace/events/ext4.h>
  60
  61 static struct ext4_lazy_init *ext4_li_info;
  62 static 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 int ext4_mark_recovery_complete(struct super_block *sb,
  70                                         struct ext4_super_block *es);
  71 static int 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_lock -> 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_lock
 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_lock
 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, int error,
 339                               __u32 ino, __u64 block,
 340                               const char *func, unsigned int line)
 341 {
 342         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 343         int err;
 344
 345         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 346         if (bdev_read_only(sb->s_bdev))
 347                 return;
 348         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 349         ext4_update_tstamp(es, s_last_error_time);
 350         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 351         es->s_last_error_line = cpu_to_le32(line);
 352         es->s_last_error_ino = cpu_to_le32(ino);
 353         es->s_last_error_block = cpu_to_le64(block);
 354         switch (error) {
 355         case EIO:
 356                 err = EXT4_ERR_EIO;
 357                 break;
 358         case ENOMEM:
 359                 err = EXT4_ERR_ENOMEM;
 360                 break;
 361         case EFSBADCRC:
 362                 err = EXT4_ERR_EFSBADCRC;
 363                 break;
 364         case 0:
 365         case EFSCORRUPTED:
 366                 err = EXT4_ERR_EFSCORRUPTED;
 367                 break;
 368         case ENOSPC:
 369                 err = EXT4_ERR_ENOSPC;
 370                 break;
 371         case ENOKEY:
 372                 err = EXT4_ERR_ENOKEY;
 373                 break;
 374         case EROFS:
 375                 err = EXT4_ERR_EROFS;
 376                 break;
 377         case EFBIG:
 378                 err = EXT4_ERR_EFBIG;
 379                 break;
 380         case EEXIST:
 381                 err = EXT4_ERR_EEXIST;
 382                 break;
 383         case ERANGE:
 384                 err = EXT4_ERR_ERANGE;
 385                 break;
 386         case EOVERFLOW:
 387                 err = EXT4_ERR_EOVERFLOW;
 388                 break;
 389         case EBUSY:
 390                 err = EXT4_ERR_EBUSY;
 391                 break;
 392         case ENOTDIR:
 393                 err = EXT4_ERR_ENOTDIR;
 394                 break;
 395         case ENOTEMPTY:
 396                 err = EXT4_ERR_ENOTEMPTY;
 397                 break;
 398         case ESHUTDOWN:
 399                 err = EXT4_ERR_ESHUTDOWN;
 400                 break;
 401         case EFAULT:
 402                 err = EXT4_ERR_EFAULT;
 403                 break;
 404         default:
 405                 err = EXT4_ERR_UNKNOWN;
 406         }
 407         es->s_last_error_errcode = err;
 408         if (!es->s_first_error_time) {
 409                 es->s_first_error_time = es->s_last_error_time;
 410                 es->s_first_error_time_hi = es->s_last_error_time_hi;
 411                 strncpy(es->s_first_error_func, func,
 412                         sizeof(es->s_first_error_func));
 413                 es->s_first_error_line = cpu_to_le32(line);
 414                 es->s_first_error_ino = es->s_last_error_ino;
 415                 es->s_first_error_block = es->s_last_error_block;
 416                 es->s_first_error_errcode = es->s_last_error_errcode;
 417         }
 418         /*
 419          * Start the daily error reporting function if it hasn't been
 420          * started already
 421          */
 422         if (!es->s_error_count)
 423                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 424         le32_add_cpu(&es->s_error_count, 1);
 425 }
 426
 427 static void save_error_info(struct super_block *sb, int error,
 428                             __u32 ino, __u64 block,
 429                             const char *func, unsigned int line)
 430 {
 431         __save_error_info(sb, error, ino, block, func, line);
 432         if (!bdev_read_only(sb->s_bdev))
 433                 ext4_commit_super(sb, 1);
 434 }
 435
 436 /*
 437  * The del_gendisk() function uninitializes the disk-specific data
 438  * structures, including the bdi structure, without telling anyone
 439  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 440  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 441  * This is a kludge to prevent these oops until we can put in a proper
 442  * hook in del_gendisk() to inform the VFS and file system layers.
 443  */
 444 static int block_device_ejected(struct super_block *sb)
 445 {
 446         struct inode *bd_inode = sb->s_bdev->bd_inode;
 447         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 448
 449         return bdi->dev == NULL;
 450 }
 451
 452 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 453 {
 454         struct super_block              *sb = journal->j_private;
 455         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 456         int                             error = is_journal_aborted(journal);
 457         struct ext4_journal_cb_entry    *jce;
 458
 459         BUG_ON(txn->t_state == T_FINISHED);
 460
 461         ext4_process_freed_data(sb, txn->t_tid);
 462
 463         spin_lock(&sbi->s_md_lock);
 464         while (!list_empty(&txn->t_private_list)) {
 465                 jce = list_entry(txn->t_private_list.next,
 466                                  struct ext4_journal_cb_entry, jce_list);
 467                 list_del_init(&jce->jce_list);
 468                 spin_unlock(&sbi->s_md_lock);
 469                 jce->jce_func(sb, jce, error);
 470                 spin_lock(&sbi->s_md_lock);
 471         }
 472         spin_unlock(&sbi->s_md_lock);
 473 }
 474
 475 static bool system_going_down(void)
 476 {
 477         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 478                 || system_state == SYSTEM_RESTART;
 479 }
 480
 481 /* Deal with the reporting of failure conditions on a filesystem such as
 482  * inconsistencies detected or read IO failures.
 483  *
 484  * On ext2, we can store the error state of the filesystem in the
 485  * superblock.  That is not possible on ext4, because we may have other
 486  * write ordering constraints on the superblock which prevent us from
 487  * writing it out straight away; and given that the journal is about to
 488  * be aborted, we can't rely on the current, or future, transactions to
 489  * write out the superblock safely.
 490  *
 491  * We'll just use the jbd2_journal_abort() error code to record an error in
 492  * the journal instead.  On recovery, the journal will complain about
 493  * that error until we've noted it down and cleared it.
 494  */
 495
 496 static void ext4_handle_error(struct super_block *sb)
 497 {
 498         if (test_opt(sb, WARN_ON_ERROR))
 499                 WARN_ON_ONCE(1);
 500
 501         if (sb_rdonly(sb))
 502                 return;
 503
 504         if (!test_opt(sb, ERRORS_CONT)) {
 505                 journal_t *journal = EXT4_SB(sb)->s_journal;
 506
 507                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 508                 if (journal)
 509                         jbd2_journal_abort(journal, -EIO);
 510         }
 511         /*
 512          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 513          * could panic during 'reboot -f' as the underlying device got already
 514          * disabled.
 515          */
 516         if (test_opt(sb, ERRORS_RO) || system_going_down()) {
 517                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 518                 /*
 519                  * Make sure updated value of ->s_mount_flags will be visible
 520                  * before ->s_flags update
 521                  */
 522                 smp_wmb();
 523                 sb->s_flags |= SB_RDONLY;
 524         } else if (test_opt(sb, ERRORS_PANIC)) {
 525                 panic("EXT4-fs (device %s): panic forced after error\n",
 526                         sb->s_id);
 527         }
 528 }
 529
 530 #define ext4_error_ratelimit(sb)                                        \
 531                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 532                              "EXT4-fs error")
 533
 534 void __ext4_error(struct super_block *sb, const char *function,
 535                   unsigned int line, int error, __u64 block,
 536                   const char *fmt, ...)
 537 {
 538         struct va_format vaf;
 539         va_list args;
 540
 541         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 542                 return;
 543
 544         trace_ext4_error(sb, function, line);
 545         if (ext4_error_ratelimit(sb)) {
 546                 va_start(args, fmt);
 547                 vaf.fmt = fmt;
 548                 vaf.va = &args;
 549                 printk(KERN_CRIT
 550                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 551                        sb->s_id, function, line, current->comm, &vaf);
 552                 va_end(args);
 553         }
 554         save_error_info(sb, error, 0, block, function, line);
 555         ext4_handle_error(sb);
 556 }
 557
 558 void __ext4_error_inode(struct inode *inode, const char *function,
 559                         unsigned int line, ext4_fsblk_t block, int error,
 560                         const char *fmt, ...)
 561 {
 562         va_list args;
 563         struct va_format vaf;
 564
 565         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 566                 return;
 567
 568         trace_ext4_error(inode->i_sb, function, line);
 569         if (ext4_error_ratelimit(inode->i_sb)) {
 570                 va_start(args, fmt);
 571                 vaf.fmt = fmt;
 572                 vaf.va = &args;
 573                 if (block)
 574                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 575                                "inode #%lu: block %llu: comm %s: %pV\n",
 576                                inode->i_sb->s_id, function, line, inode->i_ino,
 577                                block, current->comm, &vaf);
 578                 else
 579                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 580                                "inode #%lu: comm %s: %pV\n",
 581                                inode->i_sb->s_id, function, line, inode->i_ino,
 582                                current->comm, &vaf);
 583                 va_end(args);
 584         }
 585         save_error_info(inode->i_sb, error, inode->i_ino, block,
 586                         function, line);
 587         ext4_handle_error(inode->i_sb);
 588 }
 589
 590 void __ext4_error_file(struct file *file, const char *function,
 591                        unsigned int line, ext4_fsblk_t block,
 592                        const char *fmt, ...)
 593 {
 594         va_list args;
 595         struct va_format vaf;
 596         struct inode *inode = file_inode(file);
 597         char pathname[80], *path;
 598
 599         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 600                 return;
 601
 602         trace_ext4_error(inode->i_sb, function, line);
 603         if (ext4_error_ratelimit(inode->i_sb)) {
 604                 path = file_path(file, pathname, sizeof(pathname));
 605                 if (IS_ERR(path))
 606                         path = "(unknown)";
 607                 va_start(args, fmt);
 608                 vaf.fmt = fmt;
 609                 vaf.va = &args;
 610                 if (block)
 611                         printk(KERN_CRIT
 612                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 613                                "block %llu: comm %s: path %s: %pV\n",
 614                                inode->i_sb->s_id, function, line, inode->i_ino,
 615                                block, current->comm, path, &vaf);
 616                 else
 617                         printk(KERN_CRIT
 618                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 619                                "comm %s: path %s: %pV\n",
 620                                inode->i_sb->s_id, function, line, inode->i_ino,
 621                                current->comm, path, &vaf);
 622                 va_end(args);
 623         }
 624         save_error_info(inode->i_sb, EFSCORRUPTED, inode->i_ino, block,
 625                         function, line);
 626         ext4_handle_error(inode->i_sb);
 627 }
 628
 629 const char *ext4_decode_error(struct super_block *sb, int errno,
 630                               char nbuf[16])
 631 {
 632         char *errstr = NULL;
 633
 634         switch (errno) {
 635         case -EFSCORRUPTED:
 636                 errstr = "Corrupt filesystem";
 637                 break;
 638         case -EFSBADCRC:
 639                 errstr = "Filesystem failed CRC";
 640                 break;
 641         case -EIO:
 642                 errstr = "IO failure";
 643                 break;
 644         case -ENOMEM:
 645                 errstr = "Out of memory";
 646                 break;
 647         case -EROFS:
 648                 if (!sb || (EXT4_SB(sb)->s_journal &&
 649                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 650                         errstr = "Journal has aborted";
 651                 else
 652                         errstr = "Readonly filesystem";
 653                 break;
 654         default:
 655                 /* If the caller passed in an extra buffer for unknown
 656                  * errors, textualise them now.  Else we just return
 657                  * NULL. */
 658                 if (nbuf) {
 659                         /* Check for truncated error codes... */
 660                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 661                                 errstr = nbuf;
 662                 }
 663                 break;
 664         }
 665
 666         return errstr;
 667 }
 668
 669 /* __ext4_std_error decodes expected errors from journaling functions
 670  * automatically and invokes the appropriate error response.  */
 671
 672 void __ext4_std_error(struct super_block *sb, const char *function,
 673                       unsigned int line, int errno)
 674 {
 675         char nbuf[16];
 676         const char *errstr;
 677
 678         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 679                 return;
 680
 681         /* Special case: if the error is EROFS, and we're not already
 682          * inside a transaction, then there's really no point in logging
 683          * an error. */
 684         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 685                 return;
 686
 687         if (ext4_error_ratelimit(sb)) {
 688                 errstr = ext4_decode_error(sb, errno, nbuf);
 689                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 690                        sb->s_id, function, line, errstr);
 691         }
 692
 693         save_error_info(sb, -errno, 0, 0, function, line);
 694         ext4_handle_error(sb);
 695 }
 696
 697 /*
 698  * ext4_abort is a much stronger failure handler than ext4_error.  The
 699  * abort function may be used to deal with unrecoverable failures such
 700  * as journal IO errors or ENOMEM at a critical moment in log management.
 701  *
 702  * We unconditionally force the filesystem into an ABORT|READONLY state,
 703  * unless the error response on the fs has been set to panic in which
 704  * case we take the easy way out and panic immediately.
 705  */
 706
 707 void __ext4_abort(struct super_block *sb, const char *function,
 708                   unsigned int line, int error, const char *fmt, ...)
 709 {
 710         struct va_format vaf;
 711         va_list args;
 712
 713         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 714                 return;
 715
 716         save_error_info(sb, error, 0, 0, function, line);
 717         va_start(args, fmt);
 718         vaf.fmt = fmt;
 719         vaf.va = &args;
 720         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 721                sb->s_id, function, line, &vaf);
 722         va_end(args);
 723
 724         if (sb_rdonly(sb) == 0) {
 725                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 726                 if (EXT4_SB(sb)->s_journal)
 727                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 728
 729                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 730                 /*
 731                  * Make sure updated value of ->s_mount_flags will be visible
 732                  * before ->s_flags update
 733                  */
 734                 smp_wmb();
 735                 sb->s_flags |= SB_RDONLY;
 736         }
 737         if (test_opt(sb, ERRORS_PANIC) && !system_going_down())
 738                 panic("EXT4-fs panic from previous error\n");
 739 }
 740
 741 void __ext4_msg(struct super_block *sb,
 742                 const char *prefix, const char *fmt, ...)
 743 {
 744         struct va_format vaf;
 745         va_list args;
 746
 747         atomic_inc(&EXT4_SB(sb)->s_msg_count);
 748         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 749                 return;
 750
 751         va_start(args, fmt);
 752         vaf.fmt = fmt;
 753         vaf.va = &args;
 754         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 755         va_end(args);
 756 }
 757
 758 static int ext4_warning_ratelimit(struct super_block *sb)
 759 {
 760         atomic_inc(&EXT4_SB(sb)->s_warning_count);
 761         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
 762                             "EXT4-fs warning");
 763 }
 764
 765 void __ext4_warning(struct super_block *sb, const char *function,
 766                     unsigned int line, const char *fmt, ...)
 767 {
 768         struct va_format vaf;
 769         va_list args;
 770
 771         if (!ext4_warning_ratelimit(sb))
 772                 return;
 773
 774         va_start(args, fmt);
 775         vaf.fmt = fmt;
 776         vaf.va = &args;
 777         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 778                sb->s_id, function, line, &vaf);
 779         va_end(args);
 780 }
 781
 782 void __ext4_warning_inode(const struct inode *inode, const char *function,
 783                           unsigned int line, const char *fmt, ...)
 784 {
 785         struct va_format vaf;
 786         va_list args;
 787
 788         if (!ext4_warning_ratelimit(inode->i_sb))
 789                 return;
 790
 791         va_start(args, fmt);
 792         vaf.fmt = fmt;
 793         vaf.va = &args;
 794         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 795                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 796                function, line, inode->i_ino, current->comm, &vaf);
 797         va_end(args);
 798 }
 799
 800 void __ext4_grp_locked_error(const char *function, unsigned int line,
 801                              struct super_block *sb, ext4_group_t grp,
 802                              unsigned long ino, ext4_fsblk_t block,
 803                              const char *fmt, ...)
 804 __releases(bitlock)
 805 __acquires(bitlock)
 806 {
 807         struct va_format vaf;
 808         va_list args;
 809
 810         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 811                 return;
 812
 813         trace_ext4_error(sb, function, line);
 814         __save_error_info(sb, EFSCORRUPTED, ino, block, function, line);
 815
 816         if (ext4_error_ratelimit(sb)) {
 817                 va_start(args, fmt);
 818                 vaf.fmt = fmt;
 819                 vaf.va = &args;
 820                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 821                        sb->s_id, function, line, grp);
 822                 if (ino)
 823                         printk(KERN_CONT "inode %lu: ", ino);
 824                 if (block)
 825                         printk(KERN_CONT "block %llu:",
 826                                (unsigned long long) block);
 827                 printk(KERN_CONT "%pV\n", &vaf);
 828                 va_end(args);
 829         }
 830
 831         if (test_opt(sb, WARN_ON_ERROR))
 832                 WARN_ON_ONCE(1);
 833
 834         if (test_opt(sb, ERRORS_CONT)) {
 835                 ext4_commit_super(sb, 0);
 836                 return;
 837         }
 838
 839         ext4_unlock_group(sb, grp);
 840         ext4_commit_super(sb, 1);
 841         ext4_handle_error(sb);
 842         /*
 843          * We only get here in the ERRORS_RO case; relocking the group
 844          * may be dangerous, but nothing bad will happen since the
 845          * filesystem will have already been marked read/only and the
 846          * journal has been aborted.  We return 1 as a hint to callers
 847          * who might what to use the return value from
 848          * ext4_grp_locked_error() to distinguish between the
 849          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 850          * aggressively from the ext4 function in question, with a
 851          * more appropriate error code.
 852          */
 853         ext4_lock_group(sb, grp);
 854         return;
 855 }
 856
 857 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
 858                                      ext4_group_t group,
 859                                      unsigned int flags)
 860 {
 861         struct ext4_sb_info *sbi = EXT4_SB(sb);
 862         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
 863         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
 864         int ret;
 865
 866         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
 867                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
 868                                             &grp->bb_state);
 869                 if (!ret)
 870                         percpu_counter_sub(&sbi->s_freeclusters_counter,
 871                                            grp->bb_free);
 872         }
 873
 874         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
 875                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
 876                                             &grp->bb_state);
 877                 if (!ret && gdp) {
 878                         int count;
 879
 880                         count = ext4_free_inodes_count(sb, gdp);
 881                         percpu_counter_sub(&sbi->s_freeinodes_counter,
 882                                            count);
 883                 }
 884         }
 885 }
 886
 887 void ext4_update_dynamic_rev(struct super_block *sb)
 888 {
 889         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 890
 891         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 892                 return;
 893
 894         ext4_warning(sb,
 895                      "updating to rev %d because of new feature flag, "
 896                      "running e2fsck is recommended",
 897                      EXT4_DYNAMIC_REV);
 898
 899         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 900         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 901         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 902         /* leave es->s_feature_*compat flags alone */
 903         /* es->s_uuid will be set by e2fsck if empty */
 904
 905         /*
 906          * The rest of the superblock fields should be zero, and if not it
 907          * means they are likely already in use, so leave them alone.  We
 908          * can leave it up to e2fsck to clean up any inconsistencies there.
 909          */
 910 }
 911
 912 /*
 913  * Open the external journal device
 914  */
 915 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 916 {
 917         struct block_device *bdev;
 918
 919         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 920         if (IS_ERR(bdev))
 921                 goto fail;
 922         return bdev;
 923
 924 fail:
 925         ext4_msg(sb, KERN_ERR,
 926                  "failed to open journal device unknown-block(%u,%u) %ld",
 927                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
 928         return NULL;
 929 }
 930
 931 /*
 932  * Release the journal device
 933  */
 934 static void ext4_blkdev_put(struct block_device *bdev)
 935 {
 936         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 937 }
 938
 939 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 940 {
 941         struct block_device *bdev;
 942         bdev = sbi->journal_bdev;
 943         if (bdev) {
 944                 ext4_blkdev_put(bdev);
 945                 sbi->journal_bdev = NULL;
 946         }
 947 }
 948
 949 static inline struct inode *orphan_list_entry(struct list_head *l)
 950 {
 951         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 952 }
 953
 954 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 955 {
 956         struct list_head *l;
 957
 958         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 959                  le32_to_cpu(sbi->s_es->s_last_orphan));
 960
 961         printk(KERN_ERR "sb_info orphan list:\n");
 962         list_for_each(l, &sbi->s_orphan) {
 963                 struct inode *inode = orphan_list_entry(l);
 964                 printk(KERN_ERR "  "
 965                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 966                        inode->i_sb->s_id, inode->i_ino, inode,
 967                        inode->i_mode, inode->i_nlink,
 968                        NEXT_ORPHAN(inode));
 969         }
 970 }
 971
 972 #ifdef CONFIG_QUOTA
 973 static int ext4_quota_off(struct super_block *sb, int type);
 974
 975 static inline void ext4_quota_off_umount(struct super_block *sb)
 976 {
 977         int type;
 978
 979         /* Use our quota_off function to clear inode flags etc. */
 980         for (type = 0; type < EXT4_MAXQUOTAS; type++)
 981                 ext4_quota_off(sb, type);
 982 }
 983
 984 /*
 985  * This is a helper function which is used in the mount/remount
 986  * codepaths (which holds s_umount) to fetch the quota file name.
 987  */
 988 static inline char *get_qf_name(struct super_block *sb,
 989                                 struct ext4_sb_info *sbi,
 990                                 int type)
 991 {
 992         return rcu_dereference_protected(sbi->s_qf_names[type],
 993                                          lockdep_is_held(&sb->s_umount));
 994 }
 995 #else
 996 static inline void ext4_quota_off_umount(struct super_block *sb)
 997 {
 998 }
 999 #endif
1000
1001 static void ext4_put_super(struct super_block *sb)
1002 {
1003         struct ext4_sb_info *sbi = EXT4_SB(sb);
1004         struct ext4_super_block *es = sbi->s_es;
1005         struct buffer_head **group_desc;
1006         struct flex_groups **flex_groups;
1007         int aborted = 0;
1008         int i, err;
1009
1010         ext4_unregister_li_request(sb);
1011         ext4_quota_off_umount(sb);
1012
1013         destroy_workqueue(sbi->rsv_conversion_wq);
1014
1015         /*
1016          * Unregister sysfs before destroying jbd2 journal.
1017          * Since we could still access attr_journal_task attribute via sysfs
1018          * path which could have sbi->s_journal->j_task as NULL
1019          */
1020         ext4_unregister_sysfs(sb);
1021
1022         if (sbi->s_journal) {
1023                 aborted = is_journal_aborted(sbi->s_journal);
1024                 err = jbd2_journal_destroy(sbi->s_journal);
1025                 sbi->s_journal = NULL;
1026                 if ((err < 0) && !aborted) {
1027                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1028                 }
1029         }
1030
1031         ext4_es_unregister_shrinker(sbi);
1032         del_timer_sync(&sbi->s_err_report);
1033         ext4_release_system_zone(sb);
1034         ext4_mb_release(sb);
1035         ext4_ext_release(sb);
1036
1037         if (!sb_rdonly(sb) && !aborted) {
1038                 ext4_clear_feature_journal_needs_recovery(sb);
1039                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1040         }
1041         if (!sb_rdonly(sb))
1042                 ext4_commit_super(sb, 1);
1043
1044         rcu_read_lock();
1045         group_desc = rcu_dereference(sbi->s_group_desc);
1046         for (i = 0; i < sbi->s_gdb_count; i++)
1047                 brelse(group_desc[i]);
1048         kvfree(group_desc);
1049         flex_groups = rcu_dereference(sbi->s_flex_groups);
1050         if (flex_groups) {
1051                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1052                         kvfree(flex_groups[i]);
1053                 kvfree(flex_groups);
1054         }
1055         rcu_read_unlock();
1056         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1057         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1058         percpu_counter_destroy(&sbi->s_dirs_counter);
1059         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1060         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1061 #ifdef CONFIG_QUOTA
1062         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1063                 kfree(get_qf_name(sb, sbi, i));
1064 #endif
1065
1066         /* Debugging code just in case the in-memory inode orphan list
1067          * isn't empty.  The on-disk one can be non-empty if we've
1068          * detected an error and taken the fs readonly, but the
1069          * in-memory list had better be clean by this point. */
1070         if (!list_empty(&sbi->s_orphan))
1071                 dump_orphan_list(sb, sbi);
1072         J_ASSERT(list_empty(&sbi->s_orphan));
1073
1074         sync_blockdev(sb->s_bdev);
1075         invalidate_bdev(sb->s_bdev);
1076         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
1077                 /*
1078                  * Invalidate the journal device's buffers.  We don't want them
1079                  * floating about in memory - the physical journal device may
1080                  * hotswapped, and it breaks the `ro-after' testing code.
1081                  */
1082                 sync_blockdev(sbi->journal_bdev);
1083                 invalidate_bdev(sbi->journal_bdev);
1084                 ext4_blkdev_remove(sbi);
1085         }
1086
1087         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1088         sbi->s_ea_inode_cache = NULL;
1089
1090         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1091         sbi->s_ea_block_cache = NULL;
1092
1093         if (sbi->s_mmp_tsk)
1094                 kthread_stop(sbi->s_mmp_tsk);
1095         brelse(sbi->s_sbh);
1096         sb->s_fs_info = NULL;
1097         /*
1098          * Now that we are completely done shutting down the
1099          * superblock, we need to actually destroy the kobject.
1100          */
1101         kobject_put(&sbi->s_kobj);
1102         wait_for_completion(&sbi->s_kobj_unregister);
1103         if (sbi->s_chksum_driver)
1104                 crypto_free_shash(sbi->s_chksum_driver);
1105         kfree(sbi->s_blockgroup_lock);
1106         fs_put_dax(sbi->s_daxdev);
1107         fscrypt_free_dummy_context(&sbi->s_dummy_enc_ctx);
1108 #ifdef CONFIG_UNICODE
1109         utf8_unload(sbi->s_encoding);
1110 #endif
1111         kfree(sbi);
1112 }
1113
1114 static struct kmem_cache *ext4_inode_cachep;
1115
1116 /*
1117  * Called inside transaction, so use GFP_NOFS
1118  */
1119 static struct inode *ext4_alloc_inode(struct super_block *sb)
1120 {
1121         struct ext4_inode_info *ei;
1122
1123         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1124         if (!ei)
1125                 return NULL;
1126
1127         inode_set_iversion(&ei->vfs_inode, 1);
1128         spin_lock_init(&ei->i_raw_lock);
1129         INIT_LIST_HEAD(&ei->i_prealloc_list);
1130         atomic_set(&ei->i_prealloc_active, 0);
1131         spin_lock_init(&ei->i_prealloc_lock);
1132         ext4_es_init_tree(&ei->i_es_tree);
1133         rwlock_init(&ei->i_es_lock);
1134         INIT_LIST_HEAD(&ei->i_es_list);
1135         ei->i_es_all_nr = 0;
1136         ei->i_es_shk_nr = 0;
1137         ei->i_es_shrink_lblk = 0;
1138         ei->i_reserved_data_blocks = 0;
1139         spin_lock_init(&(ei->i_block_reservation_lock));
1140         ext4_init_pending_tree(&ei->i_pending_tree);
1141 #ifdef CONFIG_QUOTA
1142         ei->i_reserved_quota = 0;
1143         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1144 #endif
1145         ei->jinode = NULL;
1146         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1147         spin_lock_init(&ei->i_completed_io_lock);
1148         ei->i_sync_tid = 0;
1149         ei->i_datasync_tid = 0;
1150         atomic_set(&ei->i_unwritten, 0);
1151         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1152         return &ei->vfs_inode;
1153 }
1154
1155 static int ext4_drop_inode(struct inode *inode)
1156 {
1157         int drop = generic_drop_inode(inode);
1158
1159         if (!drop)
1160                 drop = fscrypt_drop_inode(inode);
1161
1162         trace_ext4_drop_inode(inode, drop);
1163         return drop;
1164 }
1165
1166 static void ext4_free_in_core_inode(struct inode *inode)
1167 {
1168         fscrypt_free_inode(inode);
1169         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1170 }
1171
1172 static void ext4_destroy_inode(struct inode *inode)
1173 {
1174         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1175                 ext4_msg(inode->i_sb, KERN_ERR,
1176                          "Inode %lu (%p): orphan list check failed!",
1177                          inode->i_ino, EXT4_I(inode));
1178                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1179                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1180                                 true);
1181                 dump_stack();
1182         }
1183 }
1184
1185 static void init_once(void *foo)
1186 {
1187         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1188
1189         INIT_LIST_HEAD(&ei->i_orphan);
1190         init_rwsem(&ei->xattr_sem);
1191         init_rwsem(&ei->i_data_sem);
1192         init_rwsem(&ei->i_mmap_sem);
1193         inode_init_once(&ei->vfs_inode);
1194 }
1195
1196 static int __init init_inodecache(void)
1197 {
1198         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1199                                 sizeof(struct ext4_inode_info), 0,
1200                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1201                                         SLAB_ACCOUNT),
1202                                 offsetof(struct ext4_inode_info, i_data),
1203                                 sizeof_field(struct ext4_inode_info, i_data),
1204                                 init_once);
1205         if (ext4_inode_cachep == NULL)
1206                 return -ENOMEM;
1207         return 0;
1208 }
1209
1210 static void destroy_inodecache(void)
1211 {
1212         /*
1213          * Make sure all delayed rcu free inodes are flushed before we
1214          * destroy cache.
1215          */
1216         rcu_barrier();
1217         kmem_cache_destroy(ext4_inode_cachep);
1218 }
1219
1220 void ext4_clear_inode(struct inode *inode)
1221 {
1222         invalidate_inode_buffers(inode);
1223         clear_inode(inode);
1224         ext4_discard_preallocations(inode, 0);
1225         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1226         dquot_drop(inode);
1227         if (EXT4_I(inode)->jinode) {
1228                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1229                                                EXT4_I(inode)->jinode);
1230                 jbd2_free_inode(EXT4_I(inode)->jinode);
1231                 EXT4_I(inode)->jinode = NULL;
1232         }
1233         fscrypt_put_encryption_info(inode);
1234         fsverity_cleanup_inode(inode);
1235 }
1236
1237 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1238                                         u64 ino, u32 generation)
1239 {
1240         struct inode *inode;
1241
1242         /*
1243          * Currently we don't know the generation for parent directory, so
1244          * a generation of 0 means "accept any"
1245          */
1246         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1247         if (IS_ERR(inode))
1248                 return ERR_CAST(inode);
1249         if (generation && inode->i_generation != generation) {
1250                 iput(inode);
1251                 return ERR_PTR(-ESTALE);
1252         }
1253
1254         return inode;
1255 }
1256
1257 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1258                                         int fh_len, int fh_type)
1259 {
1260         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1261                                     ext4_nfs_get_inode);
1262 }
1263
1264 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1265                                         int fh_len, int fh_type)
1266 {
1267         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1268                                     ext4_nfs_get_inode);
1269 }
1270
1271 static int ext4_nfs_commit_metadata(struct inode *inode)
1272 {
1273         struct writeback_control wbc = {
1274                 .sync_mode = WB_SYNC_ALL
1275         };
1276
1277         trace_ext4_nfs_commit_metadata(inode);
1278         return ext4_write_inode(inode, &wbc);
1279 }
1280
1281 /*
1282  * Try to release metadata pages (indirect blocks, directories) which are
1283  * mapped via the block device.  Since these pages could have journal heads
1284  * which would prevent try_to_free_buffers() from freeing them, we must use
1285  * jbd2 layer's try_to_free_buffers() function to release them.
1286  */
1287 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1288                                  gfp_t wait)
1289 {
1290         journal_t *journal = EXT4_SB(sb)->s_journal;
1291
1292         WARN_ON(PageChecked(page));
1293         if (!page_has_buffers(page))
1294                 return 0;
1295         if (journal)
1296                 return jbd2_journal_try_to_free_buffers(journal, page);
1297
1298         return try_to_free_buffers(page);
1299 }
1300
1301 #ifdef CONFIG_FS_ENCRYPTION
1302 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1303 {
1304         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1305                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1306 }
1307
1308 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1309                                                         void *fs_data)
1310 {
1311         handle_t *handle = fs_data;
1312         int res, res2, credits, retries = 0;
1313
1314         /*
1315          * Encrypting the root directory is not allowed because e2fsck expects
1316          * lost+found to exist and be unencrypted, and encrypting the root
1317          * directory would imply encrypting the lost+found directory as well as
1318          * the filename "lost+found" itself.
1319          */
1320         if (inode->i_ino == EXT4_ROOT_INO)
1321                 return -EPERM;
1322
1323         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1324                 return -EINVAL;
1325
1326         if (ext4_test_inode_flag(inode, EXT4_INODE_DAX))
1327                 return -EOPNOTSUPP;
1328
1329         res = ext4_convert_inline_data(inode);
1330         if (res)
1331                 return res;
1332
1333         /*
1334          * If a journal handle was specified, then the encryption context is
1335          * being set on a new inode via inheritance and is part of a larger
1336          * transaction to create the inode.  Otherwise the encryption context is
1337          * being set on an existing inode in its own transaction.  Only in the
1338          * latter case should the "retry on ENOSPC" logic be used.
1339          */
1340
1341         if (handle) {
1342                 res = ext4_xattr_set_handle(handle, inode,
1343                                             EXT4_XATTR_INDEX_ENCRYPTION,
1344                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1345                                             ctx, len, 0);
1346                 if (!res) {
1347                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1348                         ext4_clear_inode_state(inode,
1349                                         EXT4_STATE_MAY_INLINE_DATA);
1350                         /*
1351                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1352                          * S_DAX may be disabled
1353                          */
1354                         ext4_set_inode_flags(inode, false);
1355                 }
1356                 return res;
1357         }
1358
1359         res = dquot_initialize(inode);
1360         if (res)
1361                 return res;
1362 retry:
1363         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1364                                      &credits);
1365         if (res)
1366                 return res;
1367
1368         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1369         if (IS_ERR(handle))
1370                 return PTR_ERR(handle);
1371
1372         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1373                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1374                                     ctx, len, 0);
1375         if (!res) {
1376                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1377                 /*
1378                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1379                  * S_DAX may be disabled
1380                  */
1381                 ext4_set_inode_flags(inode, false);
1382                 res = ext4_mark_inode_dirty(handle, inode);
1383                 if (res)
1384                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1385         }
1386         res2 = ext4_journal_stop(handle);
1387
1388         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1389                 goto retry;
1390         if (!res)
1391                 res = res2;
1392         return res;
1393 }
1394
1395 static const union fscrypt_context *
1396 ext4_get_dummy_context(struct super_block *sb)
1397 {
1398         return EXT4_SB(sb)->s_dummy_enc_ctx.ctx;
1399 }
1400
1401 static bool ext4_has_stable_inodes(struct super_block *sb)
1402 {
1403         return ext4_has_feature_stable_inodes(sb);
1404 }
1405
1406 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1407                                        int *ino_bits_ret, int *lblk_bits_ret)
1408 {
1409         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1410         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1411 }
1412
1413 static const struct fscrypt_operations ext4_cryptops = {
1414         .key_prefix             = "ext4:",
1415         .get_context            = ext4_get_context,
1416         .set_context            = ext4_set_context,
1417         .get_dummy_context      = ext4_get_dummy_context,
1418         .empty_dir              = ext4_empty_dir,
1419         .max_namelen            = EXT4_NAME_LEN,
1420         .has_stable_inodes      = ext4_has_stable_inodes,
1421         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1422 };
1423 #endif
1424
1425 #ifdef CONFIG_QUOTA
1426 static const char * const quotatypes[] = INITQFNAMES;
1427 #define QTYPE2NAME(t) (quotatypes[t])
1428
1429 static int ext4_write_dquot(struct dquot *dquot);
1430 static int ext4_acquire_dquot(struct dquot *dquot);
1431 static int ext4_release_dquot(struct dquot *dquot);
1432 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1433 static int ext4_write_info(struct super_block *sb, int type);
1434 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1435                          const struct path *path);
1436 static int ext4_quota_on_mount(struct super_block *sb, int type);
1437 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1438                                size_t len, loff_t off);
1439 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1440                                 const char *data, size_t len, loff_t off);
1441 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1442                              unsigned int flags);
1443 static int ext4_enable_quotas(struct super_block *sb);
1444
1445 static struct dquot **ext4_get_dquots(struct inode *inode)
1446 {
1447         return EXT4_I(inode)->i_dquot;
1448 }
1449
1450 static const struct dquot_operations ext4_quota_operations = {
1451         .get_reserved_space     = ext4_get_reserved_space,
1452         .write_dquot            = ext4_write_dquot,
1453         .acquire_dquot          = ext4_acquire_dquot,
1454         .release_dquot          = ext4_release_dquot,
1455         .mark_dirty             = ext4_mark_dquot_dirty,
1456         .write_info             = ext4_write_info,
1457         .alloc_dquot            = dquot_alloc,
1458         .destroy_dquot          = dquot_destroy,
1459         .get_projid             = ext4_get_projid,
1460         .get_inode_usage        = ext4_get_inode_usage,
1461         .get_next_id            = dquot_get_next_id,
1462 };
1463
1464 static const struct quotactl_ops ext4_qctl_operations = {
1465         .quota_on       = ext4_quota_on,
1466         .quota_off      = ext4_quota_off,
1467         .quota_sync     = dquot_quota_sync,
1468         .get_state      = dquot_get_state,
1469         .set_info       = dquot_set_dqinfo,
1470         .get_dqblk      = dquot_get_dqblk,
1471         .set_dqblk      = dquot_set_dqblk,
1472         .get_nextdqblk  = dquot_get_next_dqblk,
1473 };
1474 #endif
1475
1476 static const struct super_operations ext4_sops = {
1477         .alloc_inode    = ext4_alloc_inode,
1478         .free_inode     = ext4_free_in_core_inode,
1479         .destroy_inode  = ext4_destroy_inode,
1480         .write_inode    = ext4_write_inode,
1481         .dirty_inode    = ext4_dirty_inode,
1482         .drop_inode     = ext4_drop_inode,
1483         .evict_inode    = ext4_evict_inode,
1484         .put_super      = ext4_put_super,
1485         .sync_fs        = ext4_sync_fs,
1486         .freeze_fs      = ext4_freeze,
1487         .unfreeze_fs    = ext4_unfreeze,
1488         .statfs         = ext4_statfs,
1489         .remount_fs     = ext4_remount,
1490         .show_options   = ext4_show_options,
1491 #ifdef CONFIG_QUOTA
1492         .quota_read     = ext4_quota_read,
1493         .quota_write    = ext4_quota_write,
1494         .get_dquots     = ext4_get_dquots,
1495 #endif
1496         .bdev_try_to_free_page = bdev_try_to_free_page,
1497 };
1498
1499 static const struct export_operations ext4_export_ops = {
1500         .fh_to_dentry = ext4_fh_to_dentry,
1501         .fh_to_parent = ext4_fh_to_parent,
1502         .get_parent = ext4_get_parent,
1503         .commit_metadata = ext4_nfs_commit_metadata,
1504 };
1505
1506 enum {
1507         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1508         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1509         Opt_nouid32, Opt_debug, Opt_removed,
1510         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1511         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1512         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1513         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1514         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1515         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1516         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1517         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1518         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1519         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
1520         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1521         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1522         Opt_nowarn_on_error, Opt_mblk_io_submit,
1523         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1524         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1525         Opt_inode_readahead_blks, Opt_journal_ioprio,
1526         Opt_dioread_nolock, Opt_dioread_lock,
1527         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1528         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1529         Opt_prefetch_block_bitmaps,
1530 };
1531
1532 static const match_table_t tokens = {
1533         {Opt_bsd_df, "bsddf"},
1534         {Opt_minix_df, "minixdf"},
1535         {Opt_grpid, "grpid"},
1536         {Opt_grpid, "bsdgroups"},
1537         {Opt_nogrpid, "nogrpid"},
1538         {Opt_nogrpid, "sysvgroups"},
1539         {Opt_resgid, "resgid=%u"},
1540         {Opt_resuid, "resuid=%u"},
1541         {Opt_sb, "sb=%u"},
1542         {Opt_err_cont, "errors=continue"},
1543         {Opt_err_panic, "errors=panic"},
1544         {Opt_err_ro, "errors=remount-ro"},
1545         {Opt_nouid32, "nouid32"},
1546         {Opt_debug, "debug"},
1547         {Opt_removed, "oldalloc"},
1548         {Opt_removed, "orlov"},
1549         {Opt_user_xattr, "user_xattr"},
1550         {Opt_nouser_xattr, "nouser_xattr"},
1551         {Opt_acl, "acl"},
1552         {Opt_noacl, "noacl"},
1553         {Opt_noload, "norecovery"},
1554         {Opt_noload, "noload"},
1555         {Opt_removed, "nobh"},
1556         {Opt_removed, "bh"},
1557         {Opt_commit, "commit=%u"},
1558         {Opt_min_batch_time, "min_batch_time=%u"},
1559         {Opt_max_batch_time, "max_batch_time=%u"},
1560         {Opt_journal_dev, "journal_dev=%u"},
1561         {Opt_journal_path, "journal_path=%s"},
1562         {Opt_journal_checksum, "journal_checksum"},
1563         {Opt_nojournal_checksum, "nojournal_checksum"},
1564         {Opt_journal_async_commit, "journal_async_commit"},
1565         {Opt_abort, "abort"},
1566         {Opt_data_journal, "data=journal"},
1567         {Opt_data_ordered, "data=ordered"},
1568         {Opt_data_writeback, "data=writeback"},
1569         {Opt_data_err_abort, "data_err=abort"},
1570         {Opt_data_err_ignore, "data_err=ignore"},
1571         {Opt_offusrjquota, "usrjquota="},
1572         {Opt_usrjquota, "usrjquota=%s"},
1573         {Opt_offgrpjquota, "grpjquota="},
1574         {Opt_grpjquota, "grpjquota=%s"},
1575         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1576         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1577         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1578         {Opt_grpquota, "grpquota"},
1579         {Opt_noquota, "noquota"},
1580         {Opt_quota, "quota"},
1581         {Opt_usrquota, "usrquota"},
1582         {Opt_prjquota, "prjquota"},
1583         {Opt_barrier, "barrier=%u"},
1584         {Opt_barrier, "barrier"},
1585         {Opt_nobarrier, "nobarrier"},
1586         {Opt_i_version, "i_version"},
1587         {Opt_dax, "dax"},
1588         {Opt_dax_always, "dax=always"},
1589         {Opt_dax_inode, "dax=inode"},
1590         {Opt_dax_never, "dax=never"},
1591         {Opt_stripe, "stripe=%u"},
1592         {Opt_delalloc, "delalloc"},
1593         {Opt_warn_on_error, "warn_on_error"},
1594         {Opt_nowarn_on_error, "nowarn_on_error"},
1595         {Opt_lazytime, "lazytime"},
1596         {Opt_nolazytime, "nolazytime"},
1597         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1598         {Opt_nodelalloc, "nodelalloc"},
1599         {Opt_removed, "mblk_io_submit"},
1600         {Opt_removed, "nomblk_io_submit"},
1601         {Opt_block_validity, "block_validity"},
1602         {Opt_noblock_validity, "noblock_validity"},
1603         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1604         {Opt_journal_ioprio, "journal_ioprio=%u"},
1605         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1606         {Opt_auto_da_alloc, "auto_da_alloc"},
1607         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1608         {Opt_dioread_nolock, "dioread_nolock"},
1609         {Opt_dioread_lock, "nodioread_nolock"},
1610         {Opt_dioread_lock, "dioread_lock"},
1611         {Opt_discard, "discard"},
1612         {Opt_nodiscard, "nodiscard"},
1613         {Opt_init_itable, "init_itable=%u"},
1614         {Opt_init_itable, "init_itable"},
1615         {Opt_noinit_itable, "noinit_itable"},
1616         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1617         {Opt_test_dummy_encryption, "test_dummy_encryption=%s"},
1618         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1619         {Opt_nombcache, "nombcache"},
1620         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1621         {Opt_prefetch_block_bitmaps, "prefetch_block_bitmaps"},
1622         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1623         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1624         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1625         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1626         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1627         {Opt_err, NULL},
1628 };
1629
1630 static ext4_fsblk_t get_sb_block(void **data)
1631 {
1632         ext4_fsblk_t    sb_block;
1633         char            *options = (char *) *data;
1634
1635         if (!options || strncmp(options, "sb=", 3) != 0)
1636                 return 1;       /* Default location */
1637
1638         options += 3;
1639         /* TODO: use simple_strtoll with >32bit ext4 */
1640         sb_block = simple_strtoul(options, &options, 0);
1641         if (*options && *options != ',') {
1642                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1643                        (char *) *data);
1644                 return 1;
1645         }
1646         if (*options == ',')
1647                 options++;
1648         *data = (void *) options;
1649
1650         return sb_block;
1651 }
1652
1653 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1654 static const char deprecated_msg[] =
1655         "Mount option \"%s\" will be removed by %s\n"
1656         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1657
1658 #ifdef CONFIG_QUOTA
1659 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1660 {
1661         struct ext4_sb_info *sbi = EXT4_SB(sb);
1662         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1663         int ret = -1;
1664
1665         if (sb_any_quota_loaded(sb) && !old_qname) {
1666                 ext4_msg(sb, KERN_ERR,
1667                         "Cannot change journaled "
1668                         "quota options when quota turned on");
1669                 return -1;
1670         }
1671         if (ext4_has_feature_quota(sb)) {
1672                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1673                          "ignored when QUOTA feature is enabled");
1674                 return 1;
1675         }
1676         qname = match_strdup(args);
1677         if (!qname) {
1678                 ext4_msg(sb, KERN_ERR,
1679                         "Not enough memory for storing quotafile name");
1680                 return -1;
1681         }
1682         if (old_qname) {
1683                 if (strcmp(old_qname, qname) == 0)
1684                         ret = 1;
1685                 else
1686                         ext4_msg(sb, KERN_ERR,
1687                                  "%s quota file already specified",
1688                                  QTYPE2NAME(qtype));
1689                 goto errout;
1690         }
1691         if (strchr(qname, '/')) {
1692                 ext4_msg(sb, KERN_ERR,
1693                         "quotafile must be on filesystem root");
1694                 goto errout;
1695         }
1696         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1697         set_opt(sb, QUOTA);
1698         return 1;
1699 errout:
1700         kfree(qname);
1701         return ret;
1702 }
1703
1704 static int clear_qf_name(struct super_block *sb, int qtype)
1705 {
1706
1707         struct ext4_sb_info *sbi = EXT4_SB(sb);
1708         char *old_qname = get_qf_name(sb, sbi, qtype);
1709
1710         if (sb_any_quota_loaded(sb) && old_qname) {
1711                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1712                         " when quota turned on");
1713                 return -1;
1714         }
1715         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1716         synchronize_rcu();
1717         kfree(old_qname);
1718         return 1;
1719 }
1720 #endif
1721
1722 #define MOPT_SET        0x0001
1723 #define MOPT_CLEAR      0x0002
1724 #define MOPT_NOSUPPORT  0x0004
1725 #define MOPT_EXPLICIT   0x0008
1726 #define MOPT_CLEAR_ERR  0x0010
1727 #define MOPT_GTE0       0x0020
1728 #ifdef CONFIG_QUOTA
1729 #define MOPT_Q          0
1730 #define MOPT_QFMT       0x0040
1731 #else
1732 #define MOPT_Q          MOPT_NOSUPPORT
1733 #define MOPT_QFMT       MOPT_NOSUPPORT
1734 #endif
1735 #define MOPT_DATAJ      0x0080
1736 #define MOPT_NO_EXT2    0x0100
1737 #define MOPT_NO_EXT3    0x0200
1738 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1739 #define MOPT_STRING     0x0400
1740 #define MOPT_SKIP       0x0800
1741
1742 static const struct mount_opts {
1743         int     token;
1744         int     mount_opt;
1745         int     flags;
1746 } ext4_mount_opts[] = {
1747         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1748         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1749         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1750         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1751         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1752         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1753         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1754          MOPT_EXT4_ONLY | MOPT_SET},
1755         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1756          MOPT_EXT4_ONLY | MOPT_CLEAR},
1757         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1758         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1759         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1760          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1761         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1762          MOPT_EXT4_ONLY | MOPT_CLEAR},
1763         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1764         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1765         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1766          MOPT_EXT4_ONLY | MOPT_CLEAR},
1767         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1768          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1769         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1770                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1771          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1772         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1773         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1774         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1775         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1776         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1777          MOPT_NO_EXT2},
1778         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1779          MOPT_NO_EXT2},
1780         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1781         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1782         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1783         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1784         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1785         {Opt_commit, 0, MOPT_GTE0},
1786         {Opt_max_batch_time, 0, MOPT_GTE0},
1787         {Opt_min_batch_time, 0, MOPT_GTE0},
1788         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1789         {Opt_init_itable, 0, MOPT_GTE0},
1790         {Opt_dax, EXT4_MOUNT_DAX_ALWAYS, MOPT_SET | MOPT_SKIP},
1791         {Opt_dax_always, EXT4_MOUNT_DAX_ALWAYS,
1792                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1793         {Opt_dax_inode, EXT4_MOUNT2_DAX_INODE,
1794                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1795         {Opt_dax_never, EXT4_MOUNT2_DAX_NEVER,
1796                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1797         {Opt_stripe, 0, MOPT_GTE0},
1798         {Opt_resuid, 0, MOPT_GTE0},
1799         {Opt_resgid, 0, MOPT_GTE0},
1800         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1801         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1802         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1803         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1804         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1805         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1806          MOPT_NO_EXT2 | MOPT_DATAJ},
1807         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1808         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1809 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1810         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1811         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1812 #else
1813         {Opt_acl, 0, MOPT_NOSUPPORT},
1814         {Opt_noacl, 0, MOPT_NOSUPPORT},
1815 #endif
1816         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1817         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1818         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1819         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1820         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1821                                                         MOPT_SET | MOPT_Q},
1822         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1823                                                         MOPT_SET | MOPT_Q},
1824         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1825                                                         MOPT_SET | MOPT_Q},
1826         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1827                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1828                                                         MOPT_CLEAR | MOPT_Q},
1829         {Opt_usrjquota, 0, MOPT_Q},
1830         {Opt_grpjquota, 0, MOPT_Q},
1831         {Opt_offusrjquota, 0, MOPT_Q},
1832         {Opt_offgrpjquota, 0, MOPT_Q},
1833         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1834         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1835         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1836         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1837         {Opt_test_dummy_encryption, 0, MOPT_STRING},
1838         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1839         {Opt_prefetch_block_bitmaps, EXT4_MOUNT_PREFETCH_BLOCK_BITMAPS,
1840          MOPT_SET},
1841         {Opt_err, 0, 0}
1842 };
1843
1844 #ifdef CONFIG_UNICODE
1845 static const struct ext4_sb_encodings {
1846         __u16 magic;
1847         char *name;
1848         char *version;
1849 } ext4_sb_encoding_map[] = {
1850         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
1851 };
1852
1853 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
1854                                  const struct ext4_sb_encodings **encoding,
1855                                  __u16 *flags)
1856 {
1857         __u16 magic = le16_to_cpu(es->s_encoding);
1858         int i;
1859
1860         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1861                 if (magic == ext4_sb_encoding_map[i].magic)
1862                         break;
1863
1864         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
1865                 return -EINVAL;
1866
1867         *encoding = &ext4_sb_encoding_map[i];
1868         *flags = le16_to_cpu(es->s_encoding_flags);
1869
1870         return 0;
1871 }
1872 #endif
1873
1874 static int ext4_set_test_dummy_encryption(struct super_block *sb,
1875                                           const char *opt,
1876                                           const substring_t *arg,
1877                                           bool is_remount)
1878 {
1879 #ifdef CONFIG_FS_ENCRYPTION
1880         struct ext4_sb_info *sbi = EXT4_SB(sb);
1881         int err;
1882
1883         /*
1884          * This mount option is just for testing, and it's not worthwhile to
1885          * implement the extra complexity (e.g. RCU protection) that would be
1886          * needed to allow it to be set or changed during remount.  We do allow
1887          * it to be specified during remount, but only if there is no change.
1888          */
1889         if (is_remount && !sbi->s_dummy_enc_ctx.ctx) {
1890                 ext4_msg(sb, KERN_WARNING,
1891                          "Can't set test_dummy_encryption on remount");
1892                 return -1;
1893         }
1894         err = fscrypt_set_test_dummy_encryption(sb, arg, &sbi->s_dummy_enc_ctx);
1895         if (err) {
1896                 if (err == -EEXIST)
1897                         ext4_msg(sb, KERN_WARNING,
1898                                  "Can't change test_dummy_encryption on remount");
1899                 else if (err == -EINVAL)
1900                         ext4_msg(sb, KERN_WARNING,
1901                                  "Value of option \"%s\" is unrecognized", opt);
1902                 else
1903                         ext4_msg(sb, KERN_WARNING,
1904                                  "Error processing option \"%s\" [%d]",
1905                                  opt, err);
1906                 return -1;
1907         }
1908         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
1909 #else
1910         ext4_msg(sb, KERN_WARNING,
1911                  "Test dummy encryption mount option ignored");
1912 #endif
1913         return 1;
1914 }
1915
1916 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1917                             substring_t *args, unsigned long *journal_devnum,
1918                             unsigned int *journal_ioprio, int is_remount)
1919 {
1920         struct ext4_sb_info *sbi = EXT4_SB(sb);
1921         const struct mount_opts *m;
1922         kuid_t uid;
1923         kgid_t gid;
1924         int arg = 0;
1925
1926 #ifdef CONFIG_QUOTA
1927         if (token == Opt_usrjquota)
1928                 return set_qf_name(sb, USRQUOTA, &args[0]);
1929         else if (token == Opt_grpjquota)
1930                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1931         else if (token == Opt_offusrjquota)
1932                 return clear_qf_name(sb, USRQUOTA);
1933         else if (token == Opt_offgrpjquota)
1934                 return clear_qf_name(sb, GRPQUOTA);
1935 #endif
1936         switch (token) {
1937         case Opt_noacl:
1938         case Opt_nouser_xattr:
1939                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1940                 break;
1941         case Opt_sb:
1942                 return 1;       /* handled by get_sb_block() */
1943         case Opt_removed:
1944                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1945                 return 1;
1946         case Opt_abort:
1947                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1948                 return 1;
1949         case Opt_i_version:
1950                 sb->s_flags |= SB_I_VERSION;
1951                 return 1;
1952         case Opt_lazytime:
1953                 sb->s_flags |= SB_LAZYTIME;
1954                 return 1;
1955         case Opt_nolazytime:
1956                 sb->s_flags &= ~SB_LAZYTIME;
1957                 return 1;
1958         }
1959
1960         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1961                 if (token == m->token)
1962                         break;
1963
1964         if (m->token == Opt_err) {
1965                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1966                          "or missing value", opt);
1967                 return -1;
1968         }
1969
1970         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1971                 ext4_msg(sb, KERN_ERR,
1972                          "Mount option \"%s\" incompatible with ext2", opt);
1973                 return -1;
1974         }
1975         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1976                 ext4_msg(sb, KERN_ERR,
1977                          "Mount option \"%s\" incompatible with ext3", opt);
1978                 return -1;
1979         }
1980
1981         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1982                 return -1;
1983         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1984                 return -1;
1985         if (m->flags & MOPT_EXPLICIT) {
1986                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1987                         set_opt2(sb, EXPLICIT_DELALLOC);
1988                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1989                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1990                 } else
1991                         return -1;
1992         }
1993         if (m->flags & MOPT_CLEAR_ERR)
1994                 clear_opt(sb, ERRORS_MASK);
1995         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1996                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1997                          "options when quota turned on");
1998                 return -1;
1999         }
2000
2001         if (m->flags & MOPT_NOSUPPORT) {
2002                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
2003         } else if (token == Opt_commit) {
2004                 if (arg == 0)
2005                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
2006                 else if (arg > INT_MAX / HZ) {
2007                         ext4_msg(sb, KERN_ERR,
2008                                  "Invalid commit interval %d, "
2009                                  "must be smaller than %d",
2010                                  arg, INT_MAX / HZ);
2011                         return -1;
2012                 }
2013                 sbi->s_commit_interval = HZ * arg;
2014         } else if (token == Opt_debug_want_extra_isize) {
2015                 if ((arg & 1) ||
2016                     (arg < 4) ||
2017                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
2018                         ext4_msg(sb, KERN_ERR,
2019                                  "Invalid want_extra_isize %d", arg);
2020                         return -1;
2021                 }
2022                 sbi->s_want_extra_isize = arg;
2023         } else if (token == Opt_max_batch_time) {
2024                 sbi->s_max_batch_time = arg;
2025         } else if (token == Opt_min_batch_time) {
2026                 sbi->s_min_batch_time = arg;
2027         } else if (token == Opt_inode_readahead_blks) {
2028                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
2029                         ext4_msg(sb, KERN_ERR,
2030                                  "EXT4-fs: inode_readahead_blks must be "
2031                                  "0 or a power of 2 smaller than 2^31");
2032                         return -1;
2033                 }
2034                 sbi->s_inode_readahead_blks = arg;
2035         } else if (token == Opt_init_itable) {
2036                 set_opt(sb, INIT_INODE_TABLE);
2037                 if (!args->from)
2038                         arg = EXT4_DEF_LI_WAIT_MULT;
2039                 sbi->s_li_wait_mult = arg;
2040         } else if (token == Opt_max_dir_size_kb) {
2041                 sbi->s_max_dir_size_kb = arg;
2042         } else if (token == Opt_stripe) {
2043                 sbi->s_stripe = arg;
2044         } else if (token == Opt_resuid) {
2045                 uid = make_kuid(current_user_ns(), arg);
2046                 if (!uid_valid(uid)) {
2047                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
2048                         return -1;
2049                 }
2050                 sbi->s_resuid = uid;
2051         } else if (token == Opt_resgid) {
2052                 gid = make_kgid(current_user_ns(), arg);
2053                 if (!gid_valid(gid)) {
2054                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
2055                         return -1;
2056                 }
2057                 sbi->s_resgid = gid;
2058         } else if (token == Opt_journal_dev) {
2059                 if (is_remount) {
2060                         ext4_msg(sb, KERN_ERR,
2061                                  "Cannot specify journal on remount");
2062                         return -1;
2063                 }
2064                 *journal_devnum = arg;
2065         } else if (token == Opt_journal_path) {
2066                 char *journal_path;
2067                 struct inode *journal_inode;
2068                 struct path path;
2069                 int error;
2070
2071                 if (is_remount) {
2072                         ext4_msg(sb, KERN_ERR,
2073                                  "Cannot specify journal on remount");
2074                         return -1;
2075                 }
2076                 journal_path = match_strdup(&args[0]);
2077                 if (!journal_path) {
2078                         ext4_msg(sb, KERN_ERR, "error: could not dup "
2079                                 "journal device string");
2080                         return -1;
2081                 }
2082
2083                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2084                 if (error) {
2085                         ext4_msg(sb, KERN_ERR, "error: could not find "
2086                                 "journal device path: error %d", error);
2087                         kfree(journal_path);
2088                         return -1;
2089                 }
2090
2091                 journal_inode = d_inode(path.dentry);
2092                 if (!S_ISBLK(journal_inode->i_mode)) {
2093                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
2094                                 "is not a block device", journal_path);
2095                         path_put(&path);
2096                         kfree(journal_path);
2097                         return -1;
2098                 }
2099
2100                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
2101                 path_put(&path);
2102                 kfree(journal_path);
2103         } else if (token == Opt_journal_ioprio) {
2104                 if (arg > 7) {
2105                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2106                                  " (must be 0-7)");
2107                         return -1;
2108                 }
2109                 *journal_ioprio =
2110                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2111         } else if (token == Opt_test_dummy_encryption) {
2112                 return ext4_set_test_dummy_encryption(sb, opt, &args[0],
2113                                                       is_remount);
2114         } else if (m->flags & MOPT_DATAJ) {
2115                 if (is_remount) {
2116                         if (!sbi->s_journal)
2117                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2118                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2119                                 ext4_msg(sb, KERN_ERR,
2120                                          "Cannot change data mode on remount");
2121                                 return -1;
2122                         }
2123                 } else {
2124                         clear_opt(sb, DATA_FLAGS);
2125                         sbi->s_mount_opt |= m->mount_opt;
2126                 }
2127 #ifdef CONFIG_QUOTA
2128         } else if (m->flags & MOPT_QFMT) {
2129                 if (sb_any_quota_loaded(sb) &&
2130                     sbi->s_jquota_fmt != m->mount_opt) {
2131                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2132                                  "quota options when quota turned on");
2133                         return -1;
2134                 }
2135                 if (ext4_has_feature_quota(sb)) {
2136                         ext4_msg(sb, KERN_INFO,
2137                                  "Quota format mount options ignored "
2138                                  "when QUOTA feature is enabled");
2139                         return 1;
2140                 }
2141                 sbi->s_jquota_fmt = m->mount_opt;
2142 #endif
2143         } else if (token == Opt_dax || token == Opt_dax_always ||
2144                    token == Opt_dax_inode || token == Opt_dax_never) {
2145 #ifdef CONFIG_FS_DAX
2146                 switch (token) {
2147                 case Opt_dax:
2148                 case Opt_dax_always:
2149                         if (is_remount &&
2150                             (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2151                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2152                         fail_dax_change_remount:
2153                                 ext4_msg(sb, KERN_ERR, "can't change "
2154                                          "dax mount option while remounting");
2155                                 return -1;
2156                         }
2157                         if (is_remount &&
2158                             (test_opt(sb, DATA_FLAGS) ==
2159                              EXT4_MOUNT_JOURNAL_DATA)) {
2160                                     ext4_msg(sb, KERN_ERR, "can't mount with "
2161                                              "both data=journal and dax");
2162                                     return -1;
2163                         }
2164                         ext4_msg(sb, KERN_WARNING,
2165                                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2166                         sbi->s_mount_opt |= EXT4_MOUNT_DAX_ALWAYS;
2167                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2168                         break;
2169                 case Opt_dax_never:
2170                         if (is_remount &&
2171                             (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2172                              (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS)))
2173                                 goto fail_dax_change_remount;
2174                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2175                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2176                         break;
2177                 case Opt_dax_inode:
2178                         if (is_remount &&
2179                             ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2180                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2181                              !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE)))
2182                                 goto fail_dax_change_remount;
2183                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2184                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2185                         /* Strictly for printing options */
2186                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_INODE;
2187                         break;
2188                 }
2189 #else
2190                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2191                 sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2192                 sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2193                 return -1;
2194 #endif
2195         } else if (token == Opt_data_err_abort) {
2196                 sbi->s_mount_opt |= m->mount_opt;
2197         } else if (token == Opt_data_err_ignore) {
2198                 sbi->s_mount_opt &= ~m->mount_opt;
2199         } else {
2200                 if (!args->from)
2201                         arg = 1;
2202                 if (m->flags & MOPT_CLEAR)
2203                         arg = !arg;
2204                 else if (unlikely(!(m->flags & MOPT_SET))) {
2205                         ext4_msg(sb, KERN_WARNING,
2206                                  "buggy handling of option %s", opt);
2207                         WARN_ON(1);
2208                         return -1;
2209                 }
2210                 if (arg != 0)
2211                         sbi->s_mount_opt |= m->mount_opt;
2212                 else
2213                         sbi->s_mount_opt &= ~m->mount_opt;
2214         }
2215         return 1;
2216 }
2217
2218 static int parse_options(char *options, struct super_block *sb,
2219                          unsigned long *journal_devnum,
2220                          unsigned int *journal_ioprio,
2221                          int is_remount)
2222 {
2223         struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2224         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2225         substring_t args[MAX_OPT_ARGS];
2226         int token;
2227
2228         if (!options)
2229                 return 1;
2230
2231         while ((p = strsep(&options, ",")) != NULL) {
2232                 if (!*p)
2233                         continue;
2234                 /*
2235                  * Initialize args struct so we know whether arg was
2236                  * found; some options take optional arguments.
2237                  */
2238                 args[0].to = args[0].from = NULL;
2239                 token = match_token(p, tokens, args);
2240                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2241                                      journal_ioprio, is_remount) < 0)
2242                         return 0;
2243         }
2244 #ifdef CONFIG_QUOTA
2245         /*
2246          * We do the test below only for project quotas. 'usrquota' and
2247          * 'grpquota' mount options are allowed even without quota feature
2248          * to support legacy quotas in quota files.
2249          */
2250         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2251                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2252                          "Cannot enable project quota enforcement.");
2253                 return 0;
2254         }
2255         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2256         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2257         if (usr_qf_name || grp_qf_name) {
2258                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2259                         clear_opt(sb, USRQUOTA);
2260
2261                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2262                         clear_opt(sb, GRPQUOTA);
2263
2264                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2265                         ext4_msg(sb, KERN_ERR, "old and new quota "
2266                                         "format mixing");
2267                         return 0;
2268                 }
2269
2270                 if (!sbi->s_jquota_fmt) {
2271                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2272                                         "not specified");
2273                         return 0;
2274                 }
2275         }
2276 #endif
2277         if (test_opt(sb, DIOREAD_NOLOCK)) {
2278                 int blocksize =
2279                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2280                 if (blocksize < PAGE_SIZE)
2281                         ext4_msg(sb, KERN_WARNING, "Warning: mounting with an "
2282                                  "experimental mount option 'dioread_nolock' "
2283                                  "for blocksize < PAGE_SIZE");
2284         }
2285         return 1;
2286 }
2287
2288 static inline void ext4_show_quota_options(struct seq_file *seq,
2289                                            struct super_block *sb)
2290 {
2291 #if defined(CONFIG_QUOTA)
2292         struct ext4_sb_info *sbi = EXT4_SB(sb);
2293         char *usr_qf_name, *grp_qf_name;
2294
2295         if (sbi->s_jquota_fmt) {
2296                 char *fmtname = "";
2297
2298                 switch (sbi->s_jquota_fmt) {
2299                 case QFMT_VFS_OLD:
2300                         fmtname = "vfsold";
2301                         break;
2302                 case QFMT_VFS_V0:
2303                         fmtname = "vfsv0";
2304                         break;
2305                 case QFMT_VFS_V1:
2306                         fmtname = "vfsv1";
2307                         break;
2308                 }
2309                 seq_printf(seq, ",jqfmt=%s", fmtname);
2310         }
2311
2312         rcu_read_lock();
2313         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2314         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2315         if (usr_qf_name)
2316                 seq_show_option(seq, "usrjquota", usr_qf_name);
2317         if (grp_qf_name)
2318                 seq_show_option(seq, "grpjquota", grp_qf_name);
2319         rcu_read_unlock();
2320 #endif
2321 }
2322
2323 static const char *token2str(int token)
2324 {
2325         const struct match_token *t;
2326
2327         for (t = tokens; t->token != Opt_err; t++)
2328                 if (t->token == token && !strchr(t->pattern, '='))
2329                         break;
2330         return t->pattern;
2331 }
2332
2333 /*
2334  * Show an option if
2335  *  - it's set to a non-default value OR
2336  *  - if the per-sb default is different from the global default
2337  */
2338 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2339                               int nodefs)
2340 {
2341         struct ext4_sb_info *sbi = EXT4_SB(sb);
2342         struct ext4_super_block *es = sbi->s_es;
2343         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2344         const struct mount_opts *m;
2345         char sep = nodefs ? '\n' : ',';
2346
2347 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2348 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2349
2350         if (sbi->s_sb_block != 1)
2351                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2352
2353         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2354                 int want_set = m->flags & MOPT_SET;
2355                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2356                     (m->flags & MOPT_CLEAR_ERR) || m->flags & MOPT_SKIP)
2357                         continue;
2358                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2359                         continue; /* skip if same as the default */
2360                 if ((want_set &&
2361                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2362                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2363                         continue; /* select Opt_noFoo vs Opt_Foo */
2364                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2365         }
2366
2367         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2368             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2369                 SEQ_OPTS_PRINT("resuid=%u",
2370                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2371         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2372             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2373                 SEQ_OPTS_PRINT("resgid=%u",
2374                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2375         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2376         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2377                 SEQ_OPTS_PUTS("errors=remount-ro");
2378         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2379                 SEQ_OPTS_PUTS("errors=continue");
2380         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2381                 SEQ_OPTS_PUTS("errors=panic");
2382         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2383                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2384         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2385                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2386         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2387                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2388         if (sb->s_flags & SB_I_VERSION)
2389                 SEQ_OPTS_PUTS("i_version");
2390         if (nodefs || sbi->s_stripe)
2391                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2392         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2393                         (sbi->s_mount_opt ^ def_mount_opt)) {
2394                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2395                         SEQ_OPTS_PUTS("data=journal");
2396                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2397                         SEQ_OPTS_PUTS("data=ordered");
2398                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2399                         SEQ_OPTS_PUTS("data=writeback");
2400         }
2401         if (nodefs ||
2402             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2403                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2404                                sbi->s_inode_readahead_blks);
2405
2406         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2407                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2408                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2409         if (nodefs || sbi->s_max_dir_size_kb)
2410                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2411         if (test_opt(sb, DATA_ERR_ABORT))
2412                 SEQ_OPTS_PUTS("data_err=abort");
2413
2414         fscrypt_show_test_dummy_encryption(seq, sep, sb);
2415
2416         if (test_opt(sb, DAX_ALWAYS)) {
2417                 if (IS_EXT2_SB(sb))
2418                         SEQ_OPTS_PUTS("dax");
2419                 else
2420                         SEQ_OPTS_PUTS("dax=always");
2421         } else if (test_opt2(sb, DAX_NEVER)) {
2422                 SEQ_OPTS_PUTS("dax=never");
2423         } else if (test_opt2(sb, DAX_INODE)) {
2424                 SEQ_OPTS_PUTS("dax=inode");
2425         }
2426
2427         ext4_show_quota_options(seq, sb);
2428         return 0;
2429 }
2430
2431 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2432 {
2433         return _ext4_show_options(seq, root->d_sb, 0);
2434 }
2435
2436 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2437 {
2438         struct super_block *sb = seq->private;
2439         int rc;
2440
2441         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2442         rc = _ext4_show_options(seq, sb, 1);
2443         seq_puts(seq, "\n");
2444         return rc;
2445 }
2446
2447 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2448                             int read_only)
2449 {
2450         struct ext4_sb_info *sbi = EXT4_SB(sb);
2451         int err = 0;
2452
2453         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2454                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2455                          "forcing read-only mode");
2456                 err = -EROFS;
2457                 goto done;
2458         }
2459         if (read_only)
2460                 goto done;
2461         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2462                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2463                          "running e2fsck is recommended");
2464         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2465                 ext4_msg(sb, KERN_WARNING,
2466                          "warning: mounting fs with errors, "
2467                          "running e2fsck is recommended");
2468         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2469                  le16_to_cpu(es->s_mnt_count) >=
2470                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2471                 ext4_msg(sb, KERN_WARNING,
2472                          "warning: maximal mount count reached, "
2473                          "running e2fsck is recommended");
2474         else if (le32_to_cpu(es->s_checkinterval) &&
2475                  (ext4_get_tstamp(es, s_lastcheck) +
2476                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2477                 ext4_msg(sb, KERN_WARNING,
2478                          "warning: checktime reached, "
2479                          "running e2fsck is recommended");
2480         if (!sbi->s_journal)
2481                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2482         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2483                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2484         le16_add_cpu(&es->s_mnt_count, 1);
2485         ext4_update_tstamp(es, s_mtime);
2486         if (sbi->s_journal)
2487                 ext4_set_feature_journal_needs_recovery(sb);
2488
2489         err = ext4_commit_super(sb, 1);
2490 done:
2491         if (test_opt(sb, DEBUG))
2492                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2493                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2494                         sb->s_blocksize,
2495                         sbi->s_groups_count,
2496                         EXT4_BLOCKS_PER_GROUP(sb),
2497                         EXT4_INODES_PER_GROUP(sb),
2498                         sbi->s_mount_opt, sbi->s_mount_opt2);
2499
2500         cleancache_init_fs(sb);
2501         return err;
2502 }
2503
2504 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2505 {
2506         struct ext4_sb_info *sbi = EXT4_SB(sb);
2507         struct flex_groups **old_groups, **new_groups;
2508         int size, i, j;
2509
2510         if (!sbi->s_log_groups_per_flex)
2511                 return 0;
2512
2513         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2514         if (size <= sbi->s_flex_groups_allocated)
2515                 return 0;
2516
2517         new_groups = kvzalloc(roundup_pow_of_two(size *
2518                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2519         if (!new_groups) {
2520                 ext4_msg(sb, KERN_ERR,
2521                          "not enough memory for %d flex group pointers", size);
2522                 return -ENOMEM;
2523         }
2524         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2525                 new_groups[i] = kvzalloc(roundup_pow_of_two(
2526                                          sizeof(struct flex_groups)),
2527                                          GFP_KERNEL);
2528                 if (!new_groups[i]) {
2529                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
2530                                 kvfree(new_groups[j]);
2531                         kvfree(new_groups);
2532                         ext4_msg(sb, KERN_ERR,
2533                                  "not enough memory for %d flex groups", size);
2534                         return -ENOMEM;
2535                 }
2536         }
2537         rcu_read_lock();
2538         old_groups = rcu_dereference(sbi->s_flex_groups);
2539         if (old_groups)
2540                 memcpy(new_groups, old_groups,
2541                        (sbi->s_flex_groups_allocated *
2542                         sizeof(struct flex_groups *)));
2543         rcu_read_unlock();
2544         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2545         sbi->s_flex_groups_allocated = size;
2546         if (old_groups)
2547                 ext4_kvfree_array_rcu(old_groups);
2548         return 0;
2549 }
2550
2551 static int ext4_fill_flex_info(struct super_block *sb)
2552 {
2553         struct ext4_sb_info *sbi = EXT4_SB(sb);
2554         struct ext4_group_desc *gdp = NULL;
2555         struct flex_groups *fg;
2556         ext4_group_t flex_group;
2557         int i, err;
2558
2559         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2560         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2561                 sbi->s_log_groups_per_flex = 0;
2562                 return 1;
2563         }
2564
2565         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2566         if (err)
2567                 goto failed;
2568
2569         for (i = 0; i < sbi->s_groups_count; i++) {
2570                 gdp = ext4_get_group_desc(sb, i, NULL);
2571
2572                 flex_group = ext4_flex_group(sbi, i);
2573                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2574                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2575                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2576                              &fg->free_clusters);
2577                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2578         }
2579
2580         return 1;
2581 failed:
2582         return 0;
2583 }
2584
2585 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2586                                    struct ext4_group_desc *gdp)
2587 {
2588         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2589         __u16 crc = 0;
2590         __le32 le_group = cpu_to_le32(block_group);
2591         struct ext4_sb_info *sbi = EXT4_SB(sb);
2592
2593         if (ext4_has_metadata_csum(sbi->s_sb)) {
2594                 /* Use new metadata_csum algorithm */
2595                 __u32 csum32;
2596                 __u16 dummy_csum = 0;
2597
2598                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2599                                      sizeof(le_group));
2600                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2601                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2602                                      sizeof(dummy_csum));
2603                 offset += sizeof(dummy_csum);
2604                 if (offset < sbi->s_desc_size)
2605                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2606                                              sbi->s_desc_size - offset);
2607
2608                 crc = csum32 & 0xFFFF;
2609                 goto out;
2610         }
2611
2612         /* old crc16 code */
2613         if (!ext4_has_feature_gdt_csum(sb))
2614                 return 0;
2615
2616         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2617         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2618         crc = crc16(crc, (__u8 *)gdp, offset);
2619         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2620         /* for checksum of struct ext4_group_desc do the rest...*/
2621         if (ext4_has_feature_64bit(sb) &&
2622             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2623                 crc = crc16(crc, (__u8 *)gdp + offset,
2624                             le16_to_cpu(sbi->s_es->s_desc_size) -
2625                                 offset);
2626
2627 out:
2628         return cpu_to_le16(crc);
2629 }
2630
2631 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2632                                 struct ext4_group_desc *gdp)
2633 {
2634         if (ext4_has_group_desc_csum(sb) &&
2635             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2636                 return 0;
2637
2638         return 1;
2639 }
2640
2641 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2642                               struct ext4_group_desc *gdp)
2643 {
2644         if (!ext4_has_group_desc_csum(sb))
2645                 return;
2646         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2647 }
2648
2649 /* Called at mount-time, super-block is locked */
2650 static int ext4_check_descriptors(struct super_block *sb,
2651                                   ext4_fsblk_t sb_block,
2652                                   ext4_group_t *first_not_zeroed)
2653 {
2654         struct ext4_sb_info *sbi = EXT4_SB(sb);
2655         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2656         ext4_fsblk_t last_block;
2657         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2658         ext4_fsblk_t block_bitmap;
2659         ext4_fsblk_t inode_bitmap;
2660         ext4_fsblk_t inode_table;
2661         int flexbg_flag = 0;
2662         ext4_group_t i, grp = sbi->s_groups_count;
2663
2664         if (ext4_has_feature_flex_bg(sb))
2665                 flexbg_flag = 1;
2666
2667         ext4_debug("Checking group descriptors");
2668
2669         for (i = 0; i < sbi->s_groups_count; i++) {
2670                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2671
2672                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2673                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2674                 else
2675                         last_block = first_block +
2676                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2677
2678                 if ((grp == sbi->s_groups_count) &&
2679                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2680                         grp = i;
2681
2682                 block_bitmap = ext4_block_bitmap(sb, gdp);
2683                 if (block_bitmap == sb_block) {
2684                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2685                                  "Block bitmap for group %u overlaps "
2686                                  "superblock", i);
2687                         if (!sb_rdonly(sb))
2688                                 return 0;
2689                 }
2690                 if (block_bitmap >= sb_block + 1 &&
2691                     block_bitmap <= last_bg_block) {
2692                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2693                                  "Block bitmap for group %u overlaps "
2694                                  "block group descriptors", i);
2695                         if (!sb_rdonly(sb))
2696                                 return 0;
2697                 }
2698                 if (block_bitmap < first_block || block_bitmap > last_block) {
2699                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2700                                "Block bitmap for group %u not in group "
2701                                "(block %llu)!", i, block_bitmap);
2702                         return 0;
2703                 }
2704                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2705                 if (inode_bitmap == sb_block) {
2706                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2707                                  "Inode bitmap for group %u overlaps "
2708                                  "superblock", i);
2709                         if (!sb_rdonly(sb))
2710                                 return 0;
2711                 }
2712                 if (inode_bitmap >= sb_block + 1 &&
2713                     inode_bitmap <= last_bg_block) {
2714                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2715                                  "Inode bitmap for group %u overlaps "
2716                                  "block group descriptors", i);
2717                         if (!sb_rdonly(sb))
2718                                 return 0;
2719                 }
2720                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2721                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2722                                "Inode bitmap for group %u not in group "
2723                                "(block %llu)!", i, inode_bitmap);
2724                         return 0;
2725                 }
2726                 inode_table = ext4_inode_table(sb, gdp);
2727                 if (inode_table == sb_block) {
2728                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2729                                  "Inode table for group %u overlaps "
2730                                  "superblock", i);
2731                         if (!sb_rdonly(sb))
2732                                 return 0;
2733                 }
2734                 if (inode_table >= sb_block + 1 &&
2735                     inode_table <= last_bg_block) {
2736                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2737                                  "Inode table for group %u overlaps "
2738                                  "block group descriptors", i);
2739                         if (!sb_rdonly(sb))
2740                                 return 0;
2741                 }
2742                 if (inode_table < first_block ||
2743                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2744                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2745                                "Inode table for group %u not in group "
2746                                "(block %llu)!", i, inode_table);
2747                         return 0;
2748                 }
2749                 ext4_lock_group(sb, i);
2750                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2751                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2752                                  "Checksum for group %u failed (%u!=%u)",
2753                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2754                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2755                         if (!sb_rdonly(sb)) {
2756                                 ext4_unlock_group(sb, i);
2757                                 return 0;
2758                         }
2759                 }
2760                 ext4_unlock_group(sb, i);
2761                 if (!flexbg_flag)
2762                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2763         }
2764         if (NULL != first_not_zeroed)
2765                 *first_not_zeroed = grp;
2766         return 1;
2767 }
2768
2769 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2770  * the superblock) which were deleted from all directories, but held open by
2771  * a process at the time of a crash.  We walk the list and try to delete these
2772  * inodes at recovery time (only with a read-write filesystem).
2773  *
2774  * In order to keep the orphan inode chain consistent during traversal (in
2775  * case of crash during recovery), we link each inode into the superblock
2776  * orphan list_head and handle it the same way as an inode deletion during
2777  * normal operation (which journals the operations for us).
2778  *
2779  * We only do an iget() and an iput() on each inode, which is very safe if we
2780  * accidentally point at an in-use or already deleted inode.  The worst that
2781  * can happen in this case is that we get a "bit already cleared" message from
2782  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2783  * e2fsck was run on this filesystem, and it must have already done the orphan
2784  * inode cleanup for us, so we can safely abort without any further action.
2785  */
2786 static void ext4_orphan_cleanup(struct super_block *sb,
2787                                 struct ext4_super_block *es)
2788 {
2789         unsigned int s_flags = sb->s_flags;
2790         int ret, nr_orphans = 0, nr_truncates = 0;
2791 #ifdef CONFIG_QUOTA
2792         int quota_update = 0;
2793         int i;
2794 #endif
2795         if (!es->s_last_orphan) {
2796                 jbd_debug(4, "no orphan inodes to clean up\n");
2797                 return;
2798         }
2799
2800         if (bdev_read_only(sb->s_bdev)) {
2801                 ext4_msg(sb, KERN_ERR, "write access "
2802                         "unavailable, skipping orphan cleanup");
2803                 return;
2804         }
2805
2806         /* Check if feature set would not allow a r/w mount */
2807         if (!ext4_feature_set_ok(sb, 0)) {
2808                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2809                          "unknown ROCOMPAT features");
2810                 return;
2811         }
2812
2813         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2814                 /* don't clear list on RO mount w/ errors */
2815                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2816                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2817                                   "clearing orphan list.\n");
2818                         es->s_last_orphan = 0;
2819                 }
2820                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2821                 return;
2822         }
2823
2824         if (s_flags & SB_RDONLY) {
2825                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2826                 sb->s_flags &= ~SB_RDONLY;
2827         }
2828 #ifdef CONFIG_QUOTA
2829         /* Needed for iput() to work correctly and not trash data */
2830         sb->s_flags |= SB_ACTIVE;
2831
2832         /*
2833          * Turn on quotas which were not enabled for read-only mounts if
2834          * filesystem has quota feature, so that they are updated correctly.
2835          */
2836         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2837                 int ret = ext4_enable_quotas(sb);
2838
2839                 if (!ret)
2840                         quota_update = 1;
2841                 else
2842                         ext4_msg(sb, KERN_ERR,
2843                                 "Cannot turn on quotas: error %d", ret);
2844         }
2845
2846         /* Turn on journaled quotas used for old sytle */
2847         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2848                 if (EXT4_SB(sb)->s_qf_names[i]) {
2849                         int ret = ext4_quota_on_mount(sb, i);
2850
2851                         if (!ret)
2852                                 quota_update = 1;
2853                         else
2854                                 ext4_msg(sb, KERN_ERR,
2855                                         "Cannot turn on journaled "
2856                                         "quota: type %d: error %d", i, ret);
2857                 }
2858         }
2859 #endif
2860
2861         while (es->s_last_orphan) {
2862                 struct inode *inode;
2863
2864                 /*
2865                  * We may have encountered an error during cleanup; if
2866                  * so, skip the rest.
2867                  */
2868                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2869                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2870                         es->s_last_orphan = 0;
2871                         break;
2872                 }
2873
2874                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2875                 if (IS_ERR(inode)) {
2876                         es->s_last_orphan = 0;
2877                         break;
2878                 }
2879
2880                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2881                 dquot_initialize(inode);
2882                 if (inode->i_nlink) {
2883                         if (test_opt(sb, DEBUG))
2884                                 ext4_msg(sb, KERN_DEBUG,
2885                                         "%s: truncating inode %lu to %lld bytes",
2886                                         __func__, inode->i_ino, inode->i_size);
2887                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2888                                   inode->i_ino, inode->i_size);
2889                         inode_lock(inode);
2890                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2891                         ret = ext4_truncate(inode);
2892                         if (ret)
2893                                 ext4_std_error(inode->i_sb, ret);
2894                         inode_unlock(inode);
2895                         nr_truncates++;
2896                 } else {
2897                         if (test_opt(sb, DEBUG))
2898                                 ext4_msg(sb, KERN_DEBUG,
2899                                         "%s: deleting unreferenced inode %lu",
2900                                         __func__, inode->i_ino);
2901                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2902                                   inode->i_ino);
2903                         nr_orphans++;
2904                 }
2905                 iput(inode);  /* The delete magic happens here! */
2906         }
2907
2908 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2909
2910         if (nr_orphans)
2911                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2912                        PLURAL(nr_orphans));
2913         if (nr_truncates)
2914                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2915                        PLURAL(nr_truncates));
2916 #ifdef CONFIG_QUOTA
2917         /* Turn off quotas if they were enabled for orphan cleanup */
2918         if (quota_update) {
2919                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2920                         if (sb_dqopt(sb)->files[i])
2921                                 dquot_quota_off(sb, i);
2922                 }
2923         }
2924 #endif
2925         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2926 }
2927
2928 /*
2929  * Maximal extent format file size.
2930  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2931  * extent format containers, within a sector_t, and within i_blocks
2932  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2933  * so that won't be a limiting factor.
2934  *
2935  * However there is other limiting factor. We do store extents in the form
2936  * of starting block and length, hence the resulting length of the extent
2937  * covering maximum file size must fit into on-disk format containers as
2938  * well. Given that length is always by 1 unit bigger than max unit (because
2939  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2940  *
2941  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2942  */
2943 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2944 {
2945         loff_t res;
2946         loff_t upper_limit = MAX_LFS_FILESIZE;
2947
2948         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
2949
2950         if (!has_huge_files) {
2951                 upper_limit = (1LL << 32) - 1;
2952
2953                 /* total blocks in file system block size */
2954                 upper_limit >>= (blkbits - 9);
2955                 upper_limit <<= blkbits;
2956         }
2957
2958         /*
2959          * 32-bit extent-start container, ee_block. We lower the maxbytes
2960          * by one fs block, so ee_len can cover the extent of maximum file
2961          * size
2962          */
2963         res = (1LL << 32) - 1;
2964         res <<= blkbits;
2965
2966         /* Sanity check against vm- & vfs- imposed limits */
2967         if (res > upper_limit)
2968                 res = upper_limit;
2969
2970         return res;
2971 }
2972
2973 /*
2974  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2975  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2976  * We need to be 1 filesystem block less than the 2^48 sector limit.
2977  */
2978 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2979 {
2980         loff_t res = EXT4_NDIR_BLOCKS;
2981         int meta_blocks;
2982         loff_t upper_limit;
2983         /* This is calculated to be the largest file size for a dense, block
2984          * mapped file such that the file's total number of 512-byte sectors,
2985          * including data and all indirect blocks, does not exceed (2^48 - 1).
2986          *
2987          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2988          * number of 512-byte sectors of the file.
2989          */
2990
2991         if (!has_huge_files) {
2992                 /*
2993                  * !has_huge_files or implies that the inode i_block field
2994                  * represents total file blocks in 2^32 512-byte sectors ==
2995                  * size of vfs inode i_blocks * 8
2996                  */
2997                 upper_limit = (1LL << 32) - 1;
2998
2999                 /* total blocks in file system block size */
3000                 upper_limit >>= (bits - 9);
3001
3002         } else {
3003                 /*
3004                  * We use 48 bit ext4_inode i_blocks
3005                  * With EXT4_HUGE_FILE_FL set the i_blocks
3006                  * represent total number of blocks in
3007                  * file system block size
3008                  */
3009                 upper_limit = (1LL << 48) - 1;
3010
3011         }
3012
3013         /* indirect blocks */
3014         meta_blocks = 1;
3015         /* double indirect blocks */
3016         meta_blocks += 1 + (1LL << (bits-2));
3017         /* tripple indirect blocks */
3018         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
3019
3020         upper_limit -= meta_blocks;
3021         upper_limit <<= bits;
3022
3023         res += 1LL << (bits-2);
3024         res += 1LL << (2*(bits-2));
3025         res += 1LL << (3*(bits-2));
3026         res <<= bits;
3027         if (res > upper_limit)
3028                 res = upper_limit;
3029
3030         if (res > MAX_LFS_FILESIZE)
3031                 res = MAX_LFS_FILESIZE;
3032
3033         return res;
3034 }
3035
3036 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3037                                    ext4_fsblk_t logical_sb_block, int nr)
3038 {
3039         struct ext4_sb_info *sbi = EXT4_SB(sb);
3040         ext4_group_t bg, first_meta_bg;
3041         int has_super = 0;
3042
3043         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3044
3045         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3046                 return logical_sb_block + nr + 1;
3047         bg = sbi->s_desc_per_block * nr;
3048         if (ext4_bg_has_super(sb, bg))
3049                 has_super = 1;
3050
3051         /*
3052          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3053          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3054          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3055          * compensate.
3056          */
3057         if (sb->s_blocksize == 1024 && nr == 0 &&
3058             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3059                 has_super++;
3060
3061         return (has_super + ext4_group_first_block_no(sb, bg));
3062 }
3063
3064 /**
3065  * ext4_get_stripe_size: Get the stripe size.
3066  * @sbi: In memory super block info
3067  *
3068  * If we have specified it via mount option, then
3069  * use the mount option value. If the value specified at mount time is
3070  * greater than the blocks per group use the super block value.
3071  * If the super block value is greater than blocks per group return 0.
3072  * Allocator needs it be less than blocks per group.
3073  *
3074  */
3075 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3076 {
3077         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3078         unsigned long stripe_width =
3079                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3080         int ret;
3081
3082         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3083                 ret = sbi->s_stripe;
3084         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3085                 ret = stripe_width;
3086         else if (stride && stride <= sbi->s_blocks_per_group)
3087                 ret = stride;
3088         else
3089                 ret = 0;
3090
3091         /*
3092          * If the stripe width is 1, this makes no sense and
3093          * we set it to 0 to turn off stripe handling code.
3094          */
3095         if (ret <= 1)
3096                 ret = 0;
3097
3098         return ret;
3099 }
3100
3101 /*
3102  * Check whether this filesystem can be mounted based on
3103  * the features present and the RDONLY/RDWR mount requested.
3104  * Returns 1 if this filesystem can be mounted as requested,
3105  * 0 if it cannot be.
3106  */
3107 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
3108 {
3109         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3110                 ext4_msg(sb, KERN_ERR,
3111                         "Couldn't mount because of "
3112                         "unsupported optional features (%x)",
3113                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3114                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3115                 return 0;
3116         }
3117
3118 #ifndef CONFIG_UNICODE
3119         if (ext4_has_feature_casefold(sb)) {
3120                 ext4_msg(sb, KERN_ERR,
3121                          "Filesystem with casefold feature cannot be "
3122                          "mounted without CONFIG_UNICODE");
3123                 return 0;
3124         }
3125 #endif
3126
3127         if (readonly)
3128                 return 1;
3129
3130         if (ext4_has_feature_readonly(sb)) {
3131                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3132                 sb->s_flags |= SB_RDONLY;
3133                 return 1;
3134         }
3135
3136         /* Check that feature set is OK for a read-write mount */
3137         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3138                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3139                          "unsupported optional features (%x)",
3140                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3141                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3142                 return 0;
3143         }
3144         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3145                 ext4_msg(sb, KERN_ERR,
3146                          "Can't support bigalloc feature without "
3147                          "extents feature\n");
3148                 return 0;
3149         }
3150
3151 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3152         if (!readonly && (ext4_has_feature_quota(sb) ||
3153                           ext4_has_feature_project(sb))) {
3154                 ext4_msg(sb, KERN_ERR,
3155                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3156                 return 0;
3157         }
3158 #endif  /* CONFIG_QUOTA */
3159         return 1;
3160 }
3161
3162 /*
3163  * This function is called once a day if we have errors logged
3164  * on the file system
3165  */
3166 static void print_daily_error_info(struct timer_list *t)
3167 {
3168         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3169         struct super_block *sb = sbi->s_sb;
3170         struct ext4_super_block *es = sbi->s_es;
3171
3172         if (es->s_error_count)
3173                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3174                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3175                          le32_to_cpu(es->s_error_count));
3176         if (es->s_first_error_time) {
3177                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3178                        sb->s_id,
3179                        ext4_get_tstamp(es, s_first_error_time),
3180                        (int) sizeof(es->s_first_error_func),
3181                        es->s_first_error_func,
3182                        le32_to_cpu(es->s_first_error_line));
3183                 if (es->s_first_error_ino)
3184                         printk(KERN_CONT ": inode %u",
3185                                le32_to_cpu(es->s_first_error_ino));
3186                 if (es->s_first_error_block)
3187                         printk(KERN_CONT ": block %llu", (unsigned long long)
3188                                le64_to_cpu(es->s_first_error_block));
3189                 printk(KERN_CONT "\n");
3190         }
3191         if (es->s_last_error_time) {
3192                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3193                        sb->s_id,
3194                        ext4_get_tstamp(es, s_last_error_time),
3195                        (int) sizeof(es->s_last_error_func),
3196                        es->s_last_error_func,
3197                        le32_to_cpu(es->s_last_error_line));
3198                 if (es->s_last_error_ino)
3199                         printk(KERN_CONT ": inode %u",
3200                                le32_to_cpu(es->s_last_error_ino));
3201                 if (es->s_last_error_block)
3202                         printk(KERN_CONT ": block %llu", (unsigned long long)
3203                                le64_to_cpu(es->s_last_error_block));
3204                 printk(KERN_CONT "\n");
3205         }
3206         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3207 }
3208
3209 /* Find next suitable group and run ext4_init_inode_table */
3210 static int ext4_run_li_request(struct ext4_li_request *elr)
3211 {
3212         struct ext4_group_desc *gdp = NULL;
3213         struct super_block *sb = elr->lr_super;
3214         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3215         ext4_group_t group = elr->lr_next_group;
3216         unsigned long timeout = 0;
3217         unsigned int prefetch_ios = 0;
3218         int ret = 0;
3219
3220         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3221                 elr->lr_next_group = ext4_mb_prefetch(sb, group,
3222                                 EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3223                 if (prefetch_ios)
3224                         ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3225                                               prefetch_ios);
3226                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3227                                             prefetch_ios);
3228                 if (group >= elr->lr_next_group) {
3229                         ret = 1;
3230                         if (elr->lr_first_not_zeroed != ngroups &&
3231                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3232                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3233                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3234                                 ret = 0;
3235                         }
3236                 }
3237                 return ret;
3238         }
3239
3240         for (; group < ngroups; group++) {
3241                 gdp = ext4_get_group_desc(sb, group, NULL);
3242                 if (!gdp) {
3243                         ret = 1;
3244                         break;
3245                 }
3246
3247                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3248                         break;
3249         }
3250
3251         if (group >= ngroups)
3252                 ret = 1;
3253
3254         if (!ret) {
3255                 timeout = jiffies;
3256                 ret = ext4_init_inode_table(sb, group,
3257                                             elr->lr_timeout ? 0 : 1);
3258                 trace_ext4_lazy_itable_init(sb, group);
3259                 if (elr->lr_timeout == 0) {
3260                         timeout = (jiffies - timeout) *
3261                                 EXT4_SB(elr->lr_super)->s_li_wait_mult;
3262                         elr->lr_timeout = timeout;
3263                 }
3264                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3265                 elr->lr_next_group = group + 1;
3266         }
3267         return ret;
3268 }
3269
3270 /*
3271  * Remove lr_request from the list_request and free the
3272  * request structure. Should be called with li_list_mtx held
3273  */
3274 static void ext4_remove_li_request(struct ext4_li_request *elr)
3275 {
3276         if (!elr)
3277                 return;
3278
3279         list_del(&elr->lr_request);
3280         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3281         kfree(elr);
3282 }
3283
3284 static void ext4_unregister_li_request(struct super_block *sb)
3285 {
3286         mutex_lock(&ext4_li_mtx);
3287         if (!ext4_li_info) {
3288                 mutex_unlock(&ext4_li_mtx);
3289                 return;
3290         }
3291
3292         mutex_lock(&ext4_li_info->li_list_mtx);
3293         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3294         mutex_unlock(&ext4_li_info->li_list_mtx);
3295         mutex_unlock(&ext4_li_mtx);
3296 }
3297
3298 static struct task_struct *ext4_lazyinit_task;
3299
3300 /*
3301  * This is the function where ext4lazyinit thread lives. It walks
3302  * through the request list searching for next scheduled filesystem.
3303  * When such a fs is found, run the lazy initialization request
3304  * (ext4_rn_li_request) and keep track of the time spend in this
3305  * function. Based on that time we compute next schedule time of
3306  * the request. When walking through the list is complete, compute
3307  * next waking time and put itself into sleep.
3308  */
3309 static int ext4_lazyinit_thread(void *arg)
3310 {
3311         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3312         struct list_head *pos, *n;
3313         struct ext4_li_request *elr;
3314         unsigned long next_wakeup, cur;
3315
3316         BUG_ON(NULL == eli);
3317
3318 cont_thread:
3319         while (true) {
3320                 next_wakeup = MAX_JIFFY_OFFSET;
3321
3322                 mutex_lock(&eli->li_list_mtx);
3323                 if (list_empty(&eli->li_request_list)) {
3324                         mutex_unlock(&eli->li_list_mtx);
3325                         goto exit_thread;
3326                 }
3327                 list_for_each_safe(pos, n, &eli->li_request_list) {
3328                         int err = 0;
3329                         int progress = 0;
3330                         elr = list_entry(pos, struct ext4_li_request,
3331                                          lr_request);
3332
3333                         if (time_before(jiffies, elr->lr_next_sched)) {
3334                                 if (time_before(elr->lr_next_sched, next_wakeup))
3335                                         next_wakeup = elr->lr_next_sched;
3336                                 continue;
3337                         }
3338                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3339                                 if (sb_start_write_trylock(elr->lr_super)) {
3340                                         progress = 1;
3341                                         /*
3342                                          * We hold sb->s_umount, sb can not
3343                                          * be removed from the list, it is
3344                                          * now safe to drop li_list_mtx
3345                                          */
3346                                         mutex_unlock(&eli->li_list_mtx);
3347                                         err = ext4_run_li_request(elr);
3348                                         sb_end_write(elr->lr_super);
3349                                         mutex_lock(&eli->li_list_mtx);
3350                                         n = pos->next;
3351                                 }
3352                                 up_read((&elr->lr_super->s_umount));
3353                         }
3354                         /* error, remove the lazy_init job */
3355                         if (err) {
3356                                 ext4_remove_li_request(elr);
3357                                 continue;
3358                         }
3359                         if (!progress) {
3360                                 elr->lr_next_sched = jiffies +
3361                                         (prandom_u32()
3362                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3363                         }
3364                         if (time_before(elr->lr_next_sched, next_wakeup))
3365                                 next_wakeup = elr->lr_next_sched;
3366                 }
3367                 mutex_unlock(&eli->li_list_mtx);
3368
3369                 try_to_freeze();
3370
3371                 cur = jiffies;
3372                 if ((time_after_eq(cur, next_wakeup)) ||
3373                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3374                         cond_resched();
3375                         continue;
3376                 }
3377
3378                 schedule_timeout_interruptible(next_wakeup - cur);
3379
3380                 if (kthread_should_stop()) {
3381                         ext4_clear_request_list();
3382                         goto exit_thread;
3383                 }
3384         }
3385
3386 exit_thread:
3387         /*
3388          * It looks like the request list is empty, but we need
3389          * to check it under the li_list_mtx lock, to prevent any
3390          * additions into it, and of course we should lock ext4_li_mtx
3391          * to atomically free the list and ext4_li_info, because at
3392          * this point another ext4 filesystem could be registering
3393          * new one.
3394          */
3395         mutex_lock(&ext4_li_mtx);
3396         mutex_lock(&eli->li_list_mtx);
3397         if (!list_empty(&eli->li_request_list)) {
3398                 mutex_unlock(&eli->li_list_mtx);
3399                 mutex_unlock(&ext4_li_mtx);
3400                 goto cont_thread;
3401         }
3402         mutex_unlock(&eli->li_list_mtx);
3403         kfree(ext4_li_info);
3404         ext4_li_info = NULL;
3405         mutex_unlock(&ext4_li_mtx);
3406
3407         return 0;
3408 }
3409
3410 static void ext4_clear_request_list(void)
3411 {
3412         struct list_head *pos, *n;
3413         struct ext4_li_request *elr;
3414
3415         mutex_lock(&ext4_li_info->li_list_mtx);
3416         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3417                 elr = list_entry(pos, struct ext4_li_request,
3418                                  lr_request);
3419                 ext4_remove_li_request(elr);
3420         }
3421         mutex_unlock(&ext4_li_info->li_list_mtx);
3422 }
3423
3424 static int ext4_run_lazyinit_thread(void)
3425 {
3426         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3427                                          ext4_li_info, "ext4lazyinit");
3428         if (IS_ERR(ext4_lazyinit_task)) {
3429                 int err = PTR_ERR(ext4_lazyinit_task);
3430                 ext4_clear_request_list();
3431                 kfree(ext4_li_info);
3432                 ext4_li_info = NULL;
3433                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3434                                  "initialization thread\n",
3435                                  err);
3436                 return err;
3437         }
3438         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3439         return 0;
3440 }
3441
3442 /*
3443  * Check whether it make sense to run itable init. thread or not.
3444  * If there is at least one uninitialized inode table, return
3445  * corresponding group number, else the loop goes through all
3446  * groups and return total number of groups.
3447  */
3448 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3449 {
3450         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3451         struct ext4_group_desc *gdp = NULL;
3452
3453         if (!ext4_has_group_desc_csum(sb))
3454                 return ngroups;
3455
3456         for (group = 0; group < ngroups; group++) {
3457                 gdp = ext4_get_group_desc(sb, group, NULL);
3458                 if (!gdp)
3459                         continue;
3460
3461                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3462                         break;
3463         }
3464
3465         return group;
3466 }
3467
3468 static int ext4_li_info_new(void)
3469 {
3470         struct ext4_lazy_init *eli = NULL;
3471
3472         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3473         if (!eli)
3474                 return -ENOMEM;
3475
3476         INIT_LIST_HEAD(&eli->li_request_list);
3477         mutex_init(&eli->li_list_mtx);
3478
3479         eli->li_state |= EXT4_LAZYINIT_QUIT;
3480
3481         ext4_li_info = eli;
3482
3483         return 0;
3484 }
3485
3486 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3487                                             ext4_group_t start)
3488 {
3489         struct ext4_li_request *elr;
3490
3491         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3492         if (!elr)
3493                 return NULL;
3494
3495         elr->lr_super = sb;
3496         elr->lr_first_not_zeroed = start;
3497         if (test_opt(sb, PREFETCH_BLOCK_BITMAPS))
3498                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3499         else {
3500                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3501                 elr->lr_next_group = start;
3502         }
3503
3504         /*
3505          * Randomize first schedule time of the request to
3506          * spread the inode table initialization requests
3507          * better.
3508          */
3509         elr->lr_next_sched = jiffies + (prandom_u32() %
3510                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3511         return elr;
3512 }
3513
3514 int ext4_register_li_request(struct super_block *sb,
3515                              ext4_group_t first_not_zeroed)
3516 {
3517         struct ext4_sb_info *sbi = EXT4_SB(sb);
3518         struct ext4_li_request *elr = NULL;
3519         ext4_group_t ngroups = sbi->s_groups_count;
3520         int ret = 0;
3521
3522         mutex_lock(&ext4_li_mtx);
3523         if (sbi->s_li_request != NULL) {
3524                 /*
3525                  * Reset timeout so it can be computed again, because
3526                  * s_li_wait_mult might have changed.
3527                  */
3528                 sbi->s_li_request->lr_timeout = 0;
3529                 goto out;
3530         }
3531
3532         if (!test_opt(sb, PREFETCH_BLOCK_BITMAPS) &&
3533             (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3534              !test_opt(sb, INIT_INODE_TABLE)))
3535                 goto out;
3536
3537         elr = ext4_li_request_new(sb, first_not_zeroed);
3538         if (!elr) {
3539                 ret = -ENOMEM;
3540                 goto out;
3541         }
3542
3543         if (NULL == ext4_li_info) {
3544                 ret = ext4_li_info_new();
3545                 if (ret)
3546                         goto out;
3547         }
3548
3549         mutex_lock(&ext4_li_info->li_list_mtx);
3550         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3551         mutex_unlock(&ext4_li_info->li_list_mtx);
3552
3553         sbi->s_li_request = elr;
3554         /*
3555          * set elr to NULL here since it has been inserted to
3556          * the request_list and the removal and free of it is
3557          * handled by ext4_clear_request_list from now on.
3558          */
3559         elr = NULL;
3560
3561         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3562                 ret = ext4_run_lazyinit_thread();
3563                 if (ret)
3564                         goto out;
3565         }
3566 out:
3567         mutex_unlock(&ext4_li_mtx);
3568         if (ret)
3569                 kfree(elr);
3570         return ret;
3571 }
3572
3573 /*
3574  * We do not need to lock anything since this is called on
3575  * module unload.
3576  */
3577 static void ext4_destroy_lazyinit_thread(void)
3578 {
3579         /*
3580          * If thread exited earlier
3581          * there's nothing to be done.
3582          */
3583         if (!ext4_li_info || !ext4_lazyinit_task)
3584                 return;
3585
3586         kthread_stop(ext4_lazyinit_task);
3587 }
3588
3589 static int set_journal_csum_feature_set(struct super_block *sb)
3590 {
3591         int ret = 1;
3592         int compat, incompat;
3593         struct ext4_sb_info *sbi = EXT4_SB(sb);
3594
3595         if (ext4_has_metadata_csum(sb)) {
3596                 /* journal checksum v3 */
3597                 compat = 0;
3598                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3599         } else {
3600                 /* journal checksum v1 */
3601                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3602                 incompat = 0;
3603         }
3604
3605         jbd2_journal_clear_features(sbi->s_journal,
3606                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3607                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3608                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3609         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3610                 ret = jbd2_journal_set_features(sbi->s_journal,
3611                                 compat, 0,
3612                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3613                                 incompat);
3614         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3615                 ret = jbd2_journal_set_features(sbi->s_journal,
3616                                 compat, 0,
3617                                 incompat);
3618                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3619                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3620         } else {
3621                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3622                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3623         }
3624
3625         return ret;
3626 }
3627
3628 /*
3629  * Note: calculating the overhead so we can be compatible with
3630  * historical BSD practice is quite difficult in the face of
3631  * clusters/bigalloc.  This is because multiple metadata blocks from
3632  * different block group can end up in the same allocation cluster.
3633  * Calculating the exact overhead in the face of clustered allocation
3634  * requires either O(all block bitmaps) in memory or O(number of block
3635  * groups**2) in time.  We will still calculate the superblock for
3636  * older file systems --- and if we come across with a bigalloc file
3637  * system with zero in s_overhead_clusters the estimate will be close to
3638  * correct especially for very large cluster sizes --- but for newer
3639  * file systems, it's better to calculate this figure once at mkfs
3640  * time, and store it in the superblock.  If the superblock value is
3641  * present (even for non-bigalloc file systems), we will use it.
3642  */
3643 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3644                           char *buf)
3645 {
3646         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3647         struct ext4_group_desc  *gdp;
3648         ext4_fsblk_t            first_block, last_block, b;
3649         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3650         int                     s, j, count = 0;
3651
3652         if (!ext4_has_feature_bigalloc(sb))
3653                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3654                         sbi->s_itb_per_group + 2);
3655
3656         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3657                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3658         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3659         for (i = 0; i < ngroups; i++) {
3660                 gdp = ext4_get_group_desc(sb, i, NULL);
3661                 b = ext4_block_bitmap(sb, gdp);
3662                 if (b >= first_block && b <= last_block) {
3663                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3664                         count++;
3665                 }
3666                 b = ext4_inode_bitmap(sb, gdp);
3667                 if (b >= first_block && b <= last_block) {
3668                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3669                         count++;
3670                 }
3671                 b = ext4_inode_table(sb, gdp);
3672                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3673                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3674                                 int c = EXT4_B2C(sbi, b - first_block);
3675                                 ext4_set_bit(c, buf);
3676                                 count++;
3677                         }
3678                 if (i != grp)
3679                         continue;
3680                 s = 0;
3681                 if (ext4_bg_has_super(sb, grp)) {
3682                         ext4_set_bit(s++, buf);
3683                         count++;
3684                 }
3685                 j = ext4_bg_num_gdb(sb, grp);
3686                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3687                         ext4_error(sb, "Invalid number of block group "
3688                                    "descriptor blocks: %d", j);
3689                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3690                 }
3691                 count += j;
3692                 for (; j > 0; j--)
3693                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3694         }
3695         if (!count)
3696                 return 0;
3697         return EXT4_CLUSTERS_PER_GROUP(sb) -
3698                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3699 }
3700
3701 /*
3702  * Compute the overhead and stash it in sbi->s_overhead
3703  */
3704 int ext4_calculate_overhead(struct super_block *sb)
3705 {
3706         struct ext4_sb_info *sbi = EXT4_SB(sb);
3707         struct ext4_super_block *es = sbi->s_es;
3708         struct inode *j_inode;
3709         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3710         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3711         ext4_fsblk_t overhead = 0;
3712         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3713
3714         if (!buf)
3715                 return -ENOMEM;
3716
3717         /*
3718          * Compute the overhead (FS structures).  This is constant
3719          * for a given filesystem unless the number of block groups
3720          * changes so we cache the previous value until it does.
3721          */
3722
3723         /*
3724          * All of the blocks before first_data_block are overhead
3725          */
3726         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3727
3728         /*
3729          * Add the overhead found in each block group
3730          */
3731         for (i = 0; i < ngroups; i++) {
3732                 int blks;
3733
3734                 blks = count_overhead(sb, i, buf);
3735                 overhead += blks;
3736                 if (blks)
3737                         memset(buf, 0, PAGE_SIZE);
3738                 cond_resched();
3739         }
3740
3741         /*
3742          * Add the internal journal blocks whether the journal has been
3743          * loaded or not
3744          */
3745         if (sbi->s_journal && !sbi->journal_bdev)
3746                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3747         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3748                 /* j_inum for internal journal is non-zero */
3749                 j_inode = ext4_get_journal_inode(sb, j_inum);
3750                 if (j_inode) {
3751                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3752                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3753                         iput(j_inode);
3754                 } else {
3755                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3756                 }
3757         }
3758         sbi->s_overhead = overhead;
3759         smp_wmb();
3760         free_page((unsigned long) buf);
3761         return 0;
3762 }
3763
3764 static void ext4_set_resv_clusters(struct super_block *sb)
3765 {
3766         ext4_fsblk_t resv_clusters;
3767         struct ext4_sb_info *sbi = EXT4_SB(sb);
3768
3769         /*
3770          * There's no need to reserve anything when we aren't using extents.
3771          * The space estimates are exact, there are no unwritten extents,
3772          * hole punching doesn't need new metadata... This is needed especially
3773          * to keep ext2/3 backward compatibility.
3774          */
3775         if (!ext4_has_feature_extents(sb))
3776                 return;
3777         /*
3778          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3779          * This should cover the situations where we can not afford to run
3780          * out of space like for example punch hole, or converting
3781          * unwritten extents in delalloc path. In most cases such
3782          * allocation would require 1, or 2 blocks, higher numbers are
3783          * very rare.
3784          */
3785         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3786                          sbi->s_cluster_bits);
3787
3788         do_div(resv_clusters, 50);
3789         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3790
3791         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3792 }
3793
3794 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3795 {
3796         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3797         char *orig_data = kstrdup(data, GFP_KERNEL);
3798         struct buffer_head *bh, **group_desc;
3799         struct ext4_super_block *es = NULL;
3800         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3801         struct flex_groups **flex_groups;
3802         ext4_fsblk_t block;
3803         ext4_fsblk_t sb_block = get_sb_block(&data);
3804         ext4_fsblk_t logical_sb_block;
3805         unsigned long offset = 0;
3806         unsigned long journal_devnum = 0;
3807         unsigned long def_mount_opts;
3808         struct inode *root;
3809         const char *descr;
3810         int ret = -ENOMEM;
3811         int blocksize, clustersize;
3812         unsigned int db_count;
3813         unsigned int i;
3814         int needs_recovery, has_huge_files;
3815         __u64 blocks_count;
3816         int err = 0;
3817         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3818         ext4_group_t first_not_zeroed;
3819
3820         if ((data && !orig_data) || !sbi)
3821                 goto out_free_base;
3822
3823         sbi->s_daxdev = dax_dev;
3824         sbi->s_blockgroup_lock =
3825                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3826         if (!sbi->s_blockgroup_lock)
3827                 goto out_free_base;
3828
3829         sb->s_fs_info = sbi;
3830         sbi->s_sb = sb;
3831         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3832         sbi->s_sb_block = sb_block;
3833         if (sb->s_bdev->bd_part)
3834                 sbi->s_sectors_written_start =
3835                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
3836
3837         /* Cleanup superblock name */
3838         strreplace(sb->s_id, '/', '!');
3839
3840         /* -EINVAL is default */
3841         ret = -EINVAL;
3842         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3843         if (!blocksize) {
3844                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3845                 goto out_fail;
3846         }
3847
3848         /*
3849          * The ext4 superblock will not be buffer aligned for other than 1kB
3850          * block sizes.  We need to calculate the offset from buffer start.
3851          */
3852         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3853                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3854                 offset = do_div(logical_sb_block, blocksize);
3855         } else {
3856                 logical_sb_block = sb_block;
3857         }
3858
3859         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3860                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3861                 goto out_fail;
3862         }
3863         /*
3864          * Note: s_es must be initialized as soon as possible because
3865          *       some ext4 macro-instructions depend on its value
3866          */
3867         es = (struct ext4_super_block *) (bh->b_data + offset);
3868         sbi->s_es = es;
3869         sb->s_magic = le16_to_cpu(es->s_magic);
3870         if (sb->s_magic != EXT4_SUPER_MAGIC)
3871                 goto cantfind_ext4;
3872         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3873
3874         /* Warn if metadata_csum and gdt_csum are both set. */
3875         if (ext4_has_feature_metadata_csum(sb) &&
3876             ext4_has_feature_gdt_csum(sb))
3877                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3878                              "redundant flags; please run fsck.");
3879
3880         /* Check for a known checksum algorithm */
3881         if (!ext4_verify_csum_type(sb, es)) {
3882                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3883                          "unknown checksum algorithm.");
3884                 silent = 1;
3885                 goto cantfind_ext4;
3886         }
3887
3888         /* Load the checksum driver */
3889         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3890         if (IS_ERR(sbi->s_chksum_driver)) {
3891                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3892                 ret = PTR_ERR(sbi->s_chksum_driver);
3893                 sbi->s_chksum_driver = NULL;
3894                 goto failed_mount;
3895         }
3896
3897         /* Check superblock checksum */
3898         if (!ext4_superblock_csum_verify(sb, es)) {
3899                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3900                          "invalid superblock checksum.  Run e2fsck?");
3901                 silent = 1;
3902                 ret = -EFSBADCRC;
3903                 goto cantfind_ext4;
3904         }
3905
3906         /* Precompute checksum seed for all metadata */
3907         if (ext4_has_feature_csum_seed(sb))
3908                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3909         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3910                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3911                                                sizeof(es->s_uuid));
3912
3913         /* Set defaults before we parse the mount options */
3914         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3915         set_opt(sb, INIT_INODE_TABLE);
3916         if (def_mount_opts & EXT4_DEFM_DEBUG)
3917                 set_opt(sb, DEBUG);
3918         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3919                 set_opt(sb, GRPID);
3920         if (def_mount_opts & EXT4_DEFM_UID16)
3921                 set_opt(sb, NO_UID32);
3922         /* xattr user namespace & acls are now defaulted on */
3923         set_opt(sb, XATTR_USER);
3924 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3925         set_opt(sb, POSIX_ACL);
3926 #endif
3927         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3928         if (ext4_has_metadata_csum(sb))
3929                 set_opt(sb, JOURNAL_CHECKSUM);
3930
3931         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3932                 set_opt(sb, JOURNAL_DATA);
3933         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3934                 set_opt(sb, ORDERED_DATA);
3935         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3936                 set_opt(sb, WRITEBACK_DATA);
3937
3938         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3939                 set_opt(sb, ERRORS_PANIC);
3940         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3941                 set_opt(sb, ERRORS_CONT);
3942         else
3943                 set_opt(sb, ERRORS_RO);
3944         /* block_validity enabled by default; disable with noblock_validity */
3945         set_opt(sb, BLOCK_VALIDITY);
3946         if (def_mount_opts & EXT4_DEFM_DISCARD)
3947                 set_opt(sb, DISCARD);
3948
3949         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3950         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3951         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3952         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3953         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3954
3955         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3956                 set_opt(sb, BARRIER);
3957
3958         /*
3959          * enable delayed allocation by default
3960          * Use -o nodelalloc to turn it off
3961          */
3962         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3963             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3964                 set_opt(sb, DELALLOC);
3965
3966         /*
3967          * set default s_li_wait_mult for lazyinit, for the case there is
3968          * no mount option specified.
3969          */
3970         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3971
3972         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3973
3974         if (blocksize == PAGE_SIZE)
3975                 set_opt(sb, DIOREAD_NOLOCK);
3976
3977         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3978             blocksize > EXT4_MAX_BLOCK_SIZE) {
3979                 ext4_msg(sb, KERN_ERR,
3980                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3981                          blocksize, le32_to_cpu(es->s_log_block_size));
3982                 goto failed_mount;
3983         }
3984
3985         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3986                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3987                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3988         } else {
3989                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3990                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3991                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
3992                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
3993                                  sbi->s_first_ino);
3994                         goto failed_mount;
3995                 }
3996                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3997                     (!is_power_of_2(sbi->s_inode_size)) ||
3998                     (sbi->s_inode_size > blocksize)) {
3999                         ext4_msg(sb, KERN_ERR,
4000                                "unsupported inode size: %d",
4001                                sbi->s_inode_size);
4002                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
4003                         goto failed_mount;
4004                 }
4005                 /*
4006                  * i_atime_extra is the last extra field available for
4007                  * [acm]times in struct ext4_inode. Checking for that
4008                  * field should suffice to ensure we have extra space
4009                  * for all three.
4010                  */
4011                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4012                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4013                         sb->s_time_gran = 1;
4014                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4015                 } else {
4016                         sb->s_time_gran = NSEC_PER_SEC;
4017                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4018                 }
4019                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4020         }
4021         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4022                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4023                         EXT4_GOOD_OLD_INODE_SIZE;
4024                 if (ext4_has_feature_extra_isize(sb)) {
4025                         unsigned v, max = (sbi->s_inode_size -
4026                                            EXT4_GOOD_OLD_INODE_SIZE);
4027
4028                         v = le16_to_cpu(es->s_want_extra_isize);
4029                         if (v > max) {
4030                                 ext4_msg(sb, KERN_ERR,
4031                                          "bad s_want_extra_isize: %d", v);
4032                                 goto failed_mount;
4033                         }
4034                         if (sbi->s_want_extra_isize < v)
4035                                 sbi->s_want_extra_isize = v;
4036
4037                         v = le16_to_cpu(es->s_min_extra_isize);
4038                         if (v > max) {
4039                                 ext4_msg(sb, KERN_ERR,
4040                                          "bad s_min_extra_isize: %d", v);
4041                                 goto failed_mount;
4042                         }
4043                         if (sbi->s_want_extra_isize < v)
4044                                 sbi->s_want_extra_isize = v;
4045                 }
4046         }
4047
4048         if (sbi->s_es->s_mount_opts[0]) {
4049                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
4050                                               sizeof(sbi->s_es->s_mount_opts),
4051                                               GFP_KERNEL);
4052                 if (!s_mount_opts)
4053                         goto failed_mount;
4054                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
4055                                    &journal_ioprio, 0)) {
4056                         ext4_msg(sb, KERN_WARNING,
4057                                  "failed to parse options in superblock: %s",
4058                                  s_mount_opts);
4059                 }
4060                 kfree(s_mount_opts);
4061         }
4062         sbi->s_def_mount_opt = sbi->s_mount_opt;
4063         if (!parse_options((char *) data, sb, &journal_devnum,
4064                            &journal_ioprio, 0))
4065                 goto failed_mount;
4066
4067 #ifdef CONFIG_UNICODE
4068         if (ext4_has_feature_casefold(sb) && !sbi->s_encoding) {
4069                 const struct ext4_sb_encodings *encoding_info;
4070                 struct unicode_map *encoding;
4071                 __u16 encoding_flags;
4072
4073                 if (ext4_has_feature_encrypt(sb)) {
4074                         ext4_msg(sb, KERN_ERR,
4075                                  "Can't mount with encoding and encryption");
4076                         goto failed_mount;
4077                 }
4078
4079                 if (ext4_sb_read_encoding(es, &encoding_info,
4080                                           &encoding_flags)) {
4081                         ext4_msg(sb, KERN_ERR,
4082                                  "Encoding requested by superblock is unknown");
4083                         goto failed_mount;
4084                 }
4085
4086                 encoding = utf8_load(encoding_info->version);
4087                 if (IS_ERR(encoding)) {
4088                         ext4_msg(sb, KERN_ERR,
4089                                  "can't mount with superblock charset: %s-%s "
4090                                  "not supported by the kernel. flags: 0x%x.",
4091                                  encoding_info->name, encoding_info->version,
4092                                  encoding_flags);
4093                         goto failed_mount;
4094                 }
4095                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4096                          "%s-%s with flags 0x%hx", encoding_info->name,
4097                          encoding_info->version?:"\b", encoding_flags);
4098
4099                 sbi->s_encoding = encoding;
4100                 sbi->s_encoding_flags = encoding_flags;
4101         }
4102 #endif
4103
4104         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4105                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, and O_DIRECT support!\n");
4106                 /* can't mount with both data=journal and dioread_nolock. */
4107                 clear_opt(sb, DIOREAD_NOLOCK);
4108                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4109                         ext4_msg(sb, KERN_ERR, "can't mount with "
4110                                  "both data=journal and delalloc");
4111                         goto failed_mount;
4112                 }
4113                 if (test_opt(sb, DAX_ALWAYS)) {
4114                         ext4_msg(sb, KERN_ERR, "can't mount with "
4115                                  "both data=journal and dax");
4116                         goto failed_mount;
4117                 }
4118                 if (ext4_has_feature_encrypt(sb)) {
4119                         ext4_msg(sb, KERN_WARNING,
4120                                  "encrypted files will use data=ordered "
4121                                  "instead of data journaling mode");
4122                 }
4123                 if (test_opt(sb, DELALLOC))
4124                         clear_opt(sb, DELALLOC);
4125         } else {
4126                 sb->s_iflags |= SB_I_CGROUPWB;
4127         }
4128
4129         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4130                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4131
4132         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4133             (ext4_has_compat_features(sb) ||
4134              ext4_has_ro_compat_features(sb) ||
4135              ext4_has_incompat_features(sb)))
4136                 ext4_msg(sb, KERN_WARNING,
4137                        "feature flags set on rev 0 fs, "
4138                        "running e2fsck is recommended");
4139
4140         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4141                 set_opt2(sb, HURD_COMPAT);
4142                 if (ext4_has_feature_64bit(sb)) {
4143                         ext4_msg(sb, KERN_ERR,
4144                                  "The Hurd can't support 64-bit file systems");
4145                         goto failed_mount;
4146                 }
4147
4148                 /*
4149                  * ea_inode feature uses l_i_version field which is not
4150                  * available in HURD_COMPAT mode.
4151                  */
4152                 if (ext4_has_feature_ea_inode(sb)) {
4153                         ext4_msg(sb, KERN_ERR,
4154                                  "ea_inode feature is not supported for Hurd");
4155                         goto failed_mount;
4156                 }
4157         }
4158
4159         if (IS_EXT2_SB(sb)) {
4160                 if (ext2_feature_set_ok(sb))
4161                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4162                                  "using the ext4 subsystem");
4163                 else {
4164                         /*
4165                          * If we're probing be silent, if this looks like
4166                          * it's actually an ext[34] filesystem.
4167                          */
4168                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4169                                 goto failed_mount;
4170                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4171                                  "to feature incompatibilities");
4172                         goto failed_mount;
4173                 }
4174         }
4175
4176         if (IS_EXT3_SB(sb)) {
4177                 if (ext3_feature_set_ok(sb))
4178                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4179                                  "using the ext4 subsystem");
4180                 else {
4181                         /*
4182                          * If we're probing be silent, if this looks like
4183                          * it's actually an ext4 filesystem.
4184                          */
4185                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4186                                 goto failed_mount;
4187                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4188                                  "to feature incompatibilities");
4189                         goto failed_mount;
4190                 }
4191         }
4192
4193         /*
4194          * Check feature flags regardless of the revision level, since we
4195          * previously didn't change the revision level when setting the flags,
4196          * so there is a chance incompat flags are set on a rev 0 filesystem.
4197          */
4198         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4199                 goto failed_mount;
4200
4201         if (le32_to_cpu(es->s_log_block_size) >
4202             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4203                 ext4_msg(sb, KERN_ERR,
4204                          "Invalid log block size: %u",
4205                          le32_to_cpu(es->s_log_block_size));
4206                 goto failed_mount;
4207         }
4208         if (le32_to_cpu(es->s_log_cluster_size) >
4209             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4210                 ext4_msg(sb, KERN_ERR,
4211                          "Invalid log cluster size: %u",
4212                          le32_to_cpu(es->s_log_cluster_size));
4213                 goto failed_mount;
4214         }
4215
4216         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4217                 ext4_msg(sb, KERN_ERR,
4218                          "Number of reserved GDT blocks insanely large: %d",
4219                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4220                 goto failed_mount;
4221         }
4222
4223         if (bdev_dax_supported(sb->s_bdev, blocksize))
4224                 set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4225
4226         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4227                 if (ext4_has_feature_inline_data(sb)) {
4228                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4229                                         " that may contain inline data");
4230                         goto failed_mount;
4231                 }
4232                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4233                         ext4_msg(sb, KERN_ERR,
4234                                 "DAX unsupported by block device.");
4235                         goto failed_mount;
4236                 }
4237         }
4238
4239         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4240                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4241                          es->s_encryption_level);
4242                 goto failed_mount;
4243         }
4244
4245         if (sb->s_blocksize != blocksize) {
4246                 /* Validate the filesystem blocksize */
4247                 if (!sb_set_blocksize(sb, blocksize)) {
4248                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4249                                         blocksize);
4250                         goto failed_mount;
4251                 }
4252
4253                 brelse(bh);
4254                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4255                 offset = do_div(logical_sb_block, blocksize);
4256                 bh = sb_bread_unmovable(sb, logical_sb_block);
4257                 if (!bh) {
4258                         ext4_msg(sb, KERN_ERR,
4259                                "Can't read superblock on 2nd try");
4260                         goto failed_mount;
4261                 }
4262                 es = (struct ext4_super_block *)(bh->b_data + offset);
4263                 sbi->s_es = es;
4264                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4265                         ext4_msg(sb, KERN_ERR,
4266                                "Magic mismatch, very weird!");
4267                         goto failed_mount;
4268                 }
4269         }
4270
4271         has_huge_files = ext4_has_feature_huge_file(sb);
4272         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4273                                                       has_huge_files);
4274         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4275
4276         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4277         if (ext4_has_feature_64bit(sb)) {
4278                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4279                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4280                     !is_power_of_2(sbi->s_desc_size)) {
4281                         ext4_msg(sb, KERN_ERR,
4282                                "unsupported descriptor size %lu",
4283                                sbi->s_desc_size);
4284                         goto failed_mount;
4285                 }
4286         } else
4287                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4288
4289         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4290         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4291
4292         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4293         if (sbi->s_inodes_per_block == 0)
4294                 goto cantfind_ext4;
4295         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4296             sbi->s_inodes_per_group > blocksize * 8) {
4297                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4298                          sbi->s_inodes_per_group);
4299                 goto failed_mount;
4300         }
4301         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4302                                         sbi->s_inodes_per_block;
4303         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4304         sbi->s_sbh = bh;
4305         sbi->s_mount_state = le16_to_cpu(es->s_state);
4306         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4307         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4308
4309         for (i = 0; i < 4; i++)
4310                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4311         sbi->s_def_hash_version = es->s_def_hash_version;
4312         if (ext4_has_feature_dir_index(sb)) {
4313                 i = le32_to_cpu(es->s_flags);
4314                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4315                         sbi->s_hash_unsigned = 3;
4316                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4317 #ifdef __CHAR_UNSIGNED__
4318                         if (!sb_rdonly(sb))
4319                                 es->s_flags |=
4320                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4321                         sbi->s_hash_unsigned = 3;
4322 #else
4323                         if (!sb_rdonly(sb))
4324                                 es->s_flags |=
4325                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4326 #endif
4327                 }
4328         }
4329
4330         /* Handle clustersize */
4331         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4332         if (ext4_has_feature_bigalloc(sb)) {
4333                 if (clustersize < blocksize) {
4334                         ext4_msg(sb, KERN_ERR,
4335                                  "cluster size (%d) smaller than "
4336                                  "block size (%d)", clustersize, blocksize);
4337                         goto failed_mount;
4338                 }
4339                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4340                         le32_to_cpu(es->s_log_block_size);
4341                 sbi->s_clusters_per_group =
4342                         le32_to_cpu(es->s_clusters_per_group);
4343                 if (sbi->s_clusters_per_group > blocksize * 8) {
4344                         ext4_msg(sb, KERN_ERR,
4345                                  "#clusters per group too big: %lu",
4346                                  sbi->s_clusters_per_group);
4347                         goto failed_mount;
4348                 }
4349                 if (sbi->s_blocks_per_group !=
4350                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4351                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4352                                  "clusters per group (%lu) inconsistent",
4353                                  sbi->s_blocks_per_group,
4354                                  sbi->s_clusters_per_group);
4355                         goto failed_mount;
4356                 }
4357         } else {
4358                 if (clustersize != blocksize) {
4359                         ext4_msg(sb, KERN_ERR,
4360                                  "fragment/cluster size (%d) != "
4361                                  "block size (%d)", clustersize, blocksize);
4362                         goto failed_mount;
4363                 }
4364                 if (sbi->s_blocks_per_group > blocksize * 8) {
4365                         ext4_msg(sb, KERN_ERR,
4366                                  "#blocks per group too big: %lu",
4367                                  sbi->s_blocks_per_group);
4368                         goto failed_mount;
4369                 }
4370                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4371                 sbi->s_cluster_bits = 0;
4372         }
4373         sbi->s_cluster_ratio = clustersize / blocksize;
4374
4375         /* Do we have standard group size of clustersize * 8 blocks ? */
4376         if (sbi->s_blocks_per_group == clustersize << 3)
4377                 set_opt2(sb, STD_GROUP_SIZE);
4378
4379         /*
4380          * Test whether we have more sectors than will fit in sector_t,
4381          * and whether the max offset is addressable by the page cache.
4382          */
4383         err = generic_check_addressable(sb->s_blocksize_bits,
4384                                         ext4_blocks_count(es));
4385         if (err) {
4386                 ext4_msg(sb, KERN_ERR, "filesystem"
4387                          " too large to mount safely on this system");
4388                 goto failed_mount;
4389         }
4390
4391         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4392                 goto cantfind_ext4;
4393
4394         /* check blocks count against device size */
4395         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4396         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4397                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4398                        "exceeds size of device (%llu blocks)",
4399                        ext4_blocks_count(es), blocks_count);
4400                 goto failed_mount;
4401         }
4402
4403         /*
4404          * It makes no sense for the first data block to be beyond the end
4405          * of the filesystem.
4406          */
4407         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4408                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4409                          "block %u is beyond end of filesystem (%llu)",
4410                          le32_to_cpu(es->s_first_data_block),
4411                          ext4_blocks_count(es));
4412                 goto failed_mount;
4413         }
4414         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4415             (sbi->s_cluster_ratio == 1)) {
4416                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4417                          "block is 0 with a 1k block and cluster size");
4418                 goto failed_mount;
4419         }
4420
4421         blocks_count = (ext4_blocks_count(es) -
4422                         le32_to_cpu(es->s_first_data_block) +
4423                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4424         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4425         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4426                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4427                        "(block count %llu, first data block %u, "
4428                        "blocks per group %lu)", blocks_count,
4429                        ext4_blocks_count(es),
4430                        le32_to_cpu(es->s_first_data_block),
4431                        EXT4_BLOCKS_PER_GROUP(sb));
4432                 goto failed_mount;
4433         }
4434         sbi->s_groups_count = blocks_count;
4435         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4436                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4437         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4438             le32_to_cpu(es->s_inodes_count)) {
4439                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4440                          le32_to_cpu(es->s_inodes_count),
4441                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4442                 ret = -EINVAL;
4443                 goto failed_mount;
4444         }
4445         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4446                    EXT4_DESC_PER_BLOCK(sb);
4447         if (ext4_has_feature_meta_bg(sb)) {
4448                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4449                         ext4_msg(sb, KERN_WARNING,
4450                                  "first meta block group too large: %u "
4451                                  "(group descriptor block count %u)",
4452                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4453                         goto failed_mount;
4454                 }
4455         }
4456         rcu_assign_pointer(sbi->s_group_desc,
4457                            kvmalloc_array(db_count,
4458                                           sizeof(struct buffer_head *),
4459                                           GFP_KERNEL));
4460         if (sbi->s_group_desc == NULL) {
4461                 ext4_msg(sb, KERN_ERR, "not enough memory");
4462                 ret = -ENOMEM;
4463                 goto failed_mount;
4464         }
4465
4466         bgl_lock_init(sbi->s_blockgroup_lock);
4467
4468         /* Pre-read the descriptors into the buffer cache */
4469         for (i = 0; i < db_count; i++) {
4470                 block = descriptor_loc(sb, logical_sb_block, i);
4471                 sb_breadahead_unmovable(sb, block);
4472         }
4473
4474         for (i = 0; i < db_count; i++) {
4475                 struct buffer_head *bh;
4476
4477                 block = descriptor_loc(sb, logical_sb_block, i);
4478                 bh = sb_bread_unmovable(sb, block);
4479                 if (!bh) {
4480                         ext4_msg(sb, KERN_ERR,
4481                                "can't read group descriptor %d", i);
4482                         db_count = i;
4483                         goto failed_mount2;
4484                 }
4485                 rcu_read_lock();
4486                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4487                 rcu_read_unlock();
4488         }
4489         sbi->s_gdb_count = db_count;
4490         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4491                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4492                 ret = -EFSCORRUPTED;
4493                 goto failed_mount2;
4494         }
4495
4496         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4497
4498         /* Register extent status tree shrinker */
4499         if (ext4_es_register_shrinker(sbi))
4500                 goto failed_mount3;
4501
4502         sbi->s_stripe = ext4_get_stripe_size(sbi);
4503         sbi->s_extent_max_zeroout_kb = 32;
4504
4505         /*
4506          * set up enough so that it can read an inode
4507          */
4508         sb->s_op = &ext4_sops;
4509         sb->s_export_op = &ext4_export_ops;
4510         sb->s_xattr = ext4_xattr_handlers;
4511 #ifdef CONFIG_FS_ENCRYPTION
4512         sb->s_cop = &ext4_cryptops;
4513 #endif
4514 #ifdef CONFIG_FS_VERITY
4515         sb->s_vop = &ext4_verityops;
4516 #endif
4517 #ifdef CONFIG_QUOTA
4518         sb->dq_op = &ext4_quota_operations;
4519         if (ext4_has_feature_quota(sb))
4520                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4521         else
4522                 sb->s_qcop = &ext4_qctl_operations;
4523         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4524 #endif
4525         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4526
4527         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4528         mutex_init(&sbi->s_orphan_lock);
4529
4530         sb->s_root = NULL;
4531
4532         needs_recovery = (es->s_last_orphan != 0 ||
4533                           ext4_has_feature_journal_needs_recovery(sb));
4534
4535         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4536                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4537                         goto failed_mount3a;
4538
4539         /*
4540          * The first inode we look at is the journal inode.  Don't try
4541          * root first: it may be modified in the journal!
4542          */
4543         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4544                 err = ext4_load_journal(sb, es, journal_devnum);
4545                 if (err)
4546                         goto failed_mount3a;
4547         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4548                    ext4_has_feature_journal_needs_recovery(sb)) {
4549                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4550                        "suppressed and not mounted read-only");
4551                 goto failed_mount_wq;
4552         } else {
4553                 /* Nojournal mode, all journal mount options are illegal */
4554                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4555                         ext4_msg(sb, KERN_ERR, "can't mount with "
4556                                  "journal_checksum, fs mounted w/o journal");
4557                         goto failed_mount_wq;
4558                 }
4559                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4560                         ext4_msg(sb, KERN_ERR, "can't mount with "
4561                                  "journal_async_commit, fs mounted w/o journal");
4562                         goto failed_mount_wq;
4563                 }
4564                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4565                         ext4_msg(sb, KERN_ERR, "can't mount with "
4566                                  "commit=%lu, fs mounted w/o journal",
4567                                  sbi->s_commit_interval / HZ);
4568                         goto failed_mount_wq;
4569                 }
4570                 if (EXT4_MOUNT_DATA_FLAGS &
4571                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4572                         ext4_msg(sb, KERN_ERR, "can't mount with "
4573                                  "data=, fs mounted w/o journal");
4574                         goto failed_mount_wq;
4575                 }
4576                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4577                 clear_opt(sb, JOURNAL_CHECKSUM);
4578                 clear_opt(sb, DATA_FLAGS);
4579                 sbi->s_journal = NULL;
4580                 needs_recovery = 0;
4581                 goto no_journal;
4582         }
4583
4584         if (ext4_has_feature_64bit(sb) &&
4585             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4586                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4587                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4588                 goto failed_mount_wq;
4589         }
4590
4591         if (!set_journal_csum_feature_set(sb)) {
4592                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4593                          "feature set");
4594                 goto failed_mount_wq;
4595         }
4596
4597         /* We have now updated the journal if required, so we can
4598          * validate the data journaling mode. */
4599         switch (test_opt(sb, DATA_FLAGS)) {
4600         case 0:
4601                 /* No mode set, assume a default based on the journal
4602                  * capabilities: ORDERED_DATA if the journal can
4603                  * cope, else JOURNAL_DATA
4604                  */
4605                 if (jbd2_journal_check_available_features
4606                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4607                         set_opt(sb, ORDERED_DATA);
4608                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4609                 } else {
4610                         set_opt(sb, JOURNAL_DATA);
4611                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4612                 }
4613                 break;
4614
4615         case EXT4_MOUNT_ORDERED_DATA:
4616         case EXT4_MOUNT_WRITEBACK_DATA:
4617                 if (!jbd2_journal_check_available_features
4618                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4619                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4620                                "requested data journaling mode");
4621                         goto failed_mount_wq;
4622                 }
4623         default:
4624                 break;
4625         }
4626
4627         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4628             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4629                 ext4_msg(sb, KERN_ERR, "can't mount with "
4630                         "journal_async_commit in data=ordered mode");
4631                 goto failed_mount_wq;
4632         }
4633
4634         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4635
4636         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4637
4638 no_journal:
4639         if (!test_opt(sb, NO_MBCACHE)) {
4640                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4641                 if (!sbi->s_ea_block_cache) {
4642                         ext4_msg(sb, KERN_ERR,
4643                                  "Failed to create ea_block_cache");
4644                         goto failed_mount_wq;
4645                 }
4646
4647                 if (ext4_has_feature_ea_inode(sb)) {
4648                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4649                         if (!sbi->s_ea_inode_cache) {
4650                                 ext4_msg(sb, KERN_ERR,
4651                                          "Failed to create ea_inode_cache");
4652                                 goto failed_mount_wq;
4653                         }
4654                 }
4655         }
4656
4657         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4658                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4659                 goto failed_mount_wq;
4660         }
4661
4662         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4663             !ext4_has_feature_encrypt(sb)) {
4664                 ext4_set_feature_encrypt(sb);
4665                 ext4_commit_super(sb, 1);
4666         }
4667
4668         /*
4669          * Get the # of file system overhead blocks from the
4670          * superblock if present.
4671          */
4672         if (es->s_overhead_clusters)
4673                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4674         else {
4675                 err = ext4_calculate_overhead(sb);
4676                 if (err)
4677                         goto failed_mount_wq;
4678         }
4679
4680         /*
4681          * The maximum number of concurrent works can be high and
4682          * concurrency isn't really necessary.  Limit it to 1.
4683          */
4684         EXT4_SB(sb)->rsv_conversion_wq =
4685                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4686         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4687                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4688                 ret = -ENOMEM;
4689                 goto failed_mount4;
4690         }
4691
4692         /*
4693          * The jbd2_journal_load will have done any necessary log recovery,
4694          * so we can safely mount the rest of the filesystem now.
4695          */
4696
4697         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4698         if (IS_ERR(root)) {
4699                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4700                 ret = PTR_ERR(root);
4701                 root = NULL;
4702                 goto failed_mount4;
4703         }
4704         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4705                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4706                 iput(root);
4707                 goto failed_mount4;
4708         }
4709
4710 #ifdef CONFIG_UNICODE
4711         if (sbi->s_encoding)
4712                 sb->s_d_op = &ext4_dentry_ops;
4713 #endif
4714
4715         sb->s_root = d_make_root(root);
4716         if (!sb->s_root) {
4717                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4718                 ret = -ENOMEM;
4719                 goto failed_mount4;
4720         }
4721
4722         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4723         if (ret == -EROFS) {
4724                 sb->s_flags |= SB_RDONLY;
4725                 ret = 0;
4726         } else if (ret)
4727                 goto failed_mount4a;
4728
4729         ext4_set_resv_clusters(sb);
4730
4731         if (test_opt(sb, BLOCK_VALIDITY)) {
4732                 err = ext4_setup_system_zone(sb);
4733                 if (err) {
4734                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
4735                                  "zone (%d)", err);
4736                         goto failed_mount4a;
4737                 }
4738         }
4739
4740         ext4_ext_init(sb);
4741         err = ext4_mb_init(sb);
4742         if (err) {
4743                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4744                          err);
4745                 goto failed_mount5;
4746         }
4747
4748         block = ext4_count_free_clusters(sb);
4749         ext4_free_blocks_count_set(sbi->s_es,
4750                                    EXT4_C2B(sbi, block));
4751         ext4_superblock_csum_set(sb);
4752         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4753                                   GFP_KERNEL);
4754         if (!err) {
4755                 unsigned long freei = ext4_count_free_inodes(sb);
4756                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4757                 ext4_superblock_csum_set(sb);
4758                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4759                                           GFP_KERNEL);
4760         }
4761         if (!err)
4762                 err = percpu_counter_init(&sbi->s_dirs_counter,
4763                                           ext4_count_dirs(sb), GFP_KERNEL);
4764         if (!err)
4765                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4766                                           GFP_KERNEL);
4767         if (!err)
4768                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
4769
4770         if (err) {
4771                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4772                 goto failed_mount6;
4773         }
4774
4775         if (ext4_has_feature_flex_bg(sb))
4776                 if (!ext4_fill_flex_info(sb)) {
4777                         ext4_msg(sb, KERN_ERR,
4778                                "unable to initialize "
4779                                "flex_bg meta info!");
4780                         goto failed_mount6;
4781                 }
4782
4783         err = ext4_register_li_request(sb, first_not_zeroed);
4784         if (err)
4785                 goto failed_mount6;
4786
4787         err = ext4_register_sysfs(sb);
4788         if (err)
4789                 goto failed_mount7;
4790
4791 #ifdef CONFIG_QUOTA
4792         /* Enable quota usage during mount. */
4793         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4794                 err = ext4_enable_quotas(sb);
4795                 if (err)
4796                         goto failed_mount8;
4797         }
4798 #endif  /* CONFIG_QUOTA */
4799
4800         /*
4801          * Save the original bdev mapping's wb_err value which could be
4802          * used to detect the metadata async write error.
4803          */
4804         spin_lock_init(&sbi->s_bdev_wb_lock);
4805         if (!sb_rdonly(sb))
4806                 errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
4807                                          &sbi->s_bdev_wb_err);
4808         sb->s_bdev->bd_super = sb;
4809         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4810         ext4_orphan_cleanup(sb, es);
4811         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4812         if (needs_recovery) {
4813                 ext4_msg(sb, KERN_INFO, "recovery complete");
4814                 err = ext4_mark_recovery_complete(sb, es);
4815                 if (err)
4816                         goto failed_mount8;
4817         }
4818         if (EXT4_SB(sb)->s_journal) {
4819                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4820                         descr = " journalled data mode";
4821                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4822                         descr = " ordered data mode";
4823                 else
4824                         descr = " writeback data mode";
4825         } else
4826                 descr = "out journal";
4827
4828         if (test_opt(sb, DISCARD)) {
4829                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4830                 if (!blk_queue_discard(q))
4831                         ext4_msg(sb, KERN_WARNING,
4832                                  "mounting with \"discard\" option, but "
4833                                  "the device does not support discard");
4834         }
4835
4836         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4837                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4838                          "Opts: %.*s%s%s", descr,
4839                          (int) sizeof(sbi->s_es->s_mount_opts),
4840                          sbi->s_es->s_mount_opts,
4841                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4842
4843         if (es->s_error_count)
4844                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4845
4846         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4847         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4848         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4849         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4850         atomic_set(&sbi->s_warning_count, 0);
4851         atomic_set(&sbi->s_msg_count, 0);
4852
4853         kfree(orig_data);
4854         return 0;
4855
4856 cantfind_ext4:
4857         if (!silent)
4858                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4859         goto failed_mount;
4860
4861 failed_mount8:
4862         ext4_unregister_sysfs(sb);
4863 failed_mount7:
4864         ext4_unregister_li_request(sb);
4865 failed_mount6:
4866         ext4_mb_release(sb);
4867         rcu_read_lock();
4868         flex_groups = rcu_dereference(sbi->s_flex_groups);
4869         if (flex_groups) {
4870                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
4871                         kvfree(flex_groups[i]);
4872                 kvfree(flex_groups);
4873         }
4874         rcu_read_unlock();
4875         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4876         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4877         percpu_counter_destroy(&sbi->s_dirs_counter);
4878         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4879         percpu_free_rwsem(&sbi->s_writepages_rwsem);
4880 failed_mount5:
4881         ext4_ext_release(sb);
4882         ext4_release_system_zone(sb);
4883 failed_mount4a:
4884         dput(sb->s_root);
4885         sb->s_root = NULL;
4886 failed_mount4:
4887         ext4_msg(sb, KERN_ERR, "mount failed");
4888         if (EXT4_SB(sb)->rsv_conversion_wq)
4889                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4890 failed_mount_wq:
4891         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4892         sbi->s_ea_inode_cache = NULL;
4893
4894         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4895         sbi->s_ea_block_cache = NULL;
4896
4897         if (sbi->s_journal) {
4898                 jbd2_journal_destroy(sbi->s_journal);
4899                 sbi->s_journal = NULL;
4900         }
4901 failed_mount3a:
4902         ext4_es_unregister_shrinker(sbi);
4903 failed_mount3:
4904         del_timer_sync(&sbi->s_err_report);
4905         if (sbi->s_mmp_tsk)
4906                 kthread_stop(sbi->s_mmp_tsk);
4907 failed_mount2:
4908         rcu_read_lock();
4909         group_desc = rcu_dereference(sbi->s_group_desc);
4910         for (i = 0; i < db_count; i++)
4911                 brelse(group_desc[i]);
4912         kvfree(group_desc);
4913         rcu_read_unlock();
4914 failed_mount:
4915         if (sbi->s_chksum_driver)
4916                 crypto_free_shash(sbi->s_chksum_driver);
4917
4918 #ifdef CONFIG_UNICODE
4919         utf8_unload(sbi->s_encoding);
4920 #endif
4921
4922 #ifdef CONFIG_QUOTA
4923         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4924                 kfree(get_qf_name(sb, sbi, i));
4925 #endif
4926         fscrypt_free_dummy_context(&sbi->s_dummy_enc_ctx);
4927         ext4_blkdev_remove(sbi);
4928         brelse(bh);
4929 out_fail:
4930         sb->s_fs_info = NULL;
4931         kfree(sbi->s_blockgroup_lock);
4932 out_free_base:
4933         kfree(sbi);
4934         kfree(orig_data);
4935         fs_put_dax(dax_dev);
4936         return err ? err : ret;
4937 }
4938
4939 /*
4940  * Setup any per-fs journal parameters now.  We'll do this both on
4941  * initial mount, once the journal has been initialised but before we've
4942  * done any recovery; and again on any subsequent remount.
4943  */
4944 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4945 {
4946         struct ext4_sb_info *sbi = EXT4_SB(sb);
4947
4948         journal->j_commit_interval = sbi->s_commit_interval;
4949         journal->j_min_batch_time = sbi->s_min_batch_time;
4950         journal->j_max_batch_time = sbi->s_max_batch_time;
4951
4952         write_lock(&journal->j_state_lock);
4953         if (test_opt(sb, BARRIER))
4954                 journal->j_flags |= JBD2_BARRIER;
4955         else
4956                 journal->j_flags &= ~JBD2_BARRIER;
4957         if (test_opt(sb, DATA_ERR_ABORT))
4958                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4959         else
4960                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4961         write_unlock(&journal->j_state_lock);
4962 }
4963
4964 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4965                                              unsigned int journal_inum)
4966 {
4967         struct inode *journal_inode;
4968
4969         /*
4970          * Test for the existence of a valid inode on disk.  Bad things
4971          * happen if we iget() an unused inode, as the subsequent iput()
4972          * will try to delete it.
4973          */
4974         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
4975         if (IS_ERR(journal_inode)) {
4976                 ext4_msg(sb, KERN_ERR, "no journal found");
4977                 return NULL;
4978         }
4979         if (!journal_inode->i_nlink) {
4980                 make_bad_inode(journal_inode);
4981                 iput(journal_inode);
4982                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4983                 return NULL;
4984         }
4985
4986         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4987                   journal_inode, journal_inode->i_size);
4988         if (!S_ISREG(journal_inode->i_mode)) {
4989                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4990                 iput(journal_inode);
4991                 return NULL;
4992         }
4993         return journal_inode;
4994 }
4995
4996 static journal_t *ext4_get_journal(struct super_block *sb,
4997                                    unsigned int journal_inum)
4998 {
4999         struct inode *journal_inode;
5000         journal_t *journal;
5001
5002         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5003                 return NULL;
5004
5005         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5006         if (!journal_inode)
5007                 return NULL;
5008
5009         journal = jbd2_journal_init_inode(journal_inode);
5010         if (!journal) {
5011                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5012                 iput(journal_inode);
5013                 return NULL;
5014         }
5015         journal->j_private = sb;
5016         ext4_init_journal_params(sb, journal);
5017         return journal;
5018 }
5019
5020 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5021                                        dev_t j_dev)
5022 {
5023         struct buffer_head *bh;
5024         journal_t *journal;
5025         ext4_fsblk_t start;
5026         ext4_fsblk_t len;
5027         int hblock, blocksize;
5028         ext4_fsblk_t sb_block;
5029         unsigned long offset;
5030         struct ext4_super_block *es;
5031         struct block_device *bdev;
5032
5033         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5034                 return NULL;
5035
5036         bdev = ext4_blkdev_get(j_dev, sb);
5037         if (bdev == NULL)
5038                 return NULL;
5039
5040         blocksize = sb->s_blocksize;
5041         hblock = bdev_logical_block_size(bdev);
5042         if (blocksize < hblock) {
5043                 ext4_msg(sb, KERN_ERR,
5044                         "blocksize too small for journal device");
5045                 goto out_bdev;
5046         }
5047
5048         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5049         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5050         set_blocksize(bdev, blocksize);
5051         if (!(bh = __bread(bdev, sb_block, blocksize))) {
5052                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5053                        "external journal");
5054                 goto out_bdev;
5055         }
5056
5057         es = (struct ext4_super_block *) (bh->b_data + offset);
5058         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5059             !(le32_to_cpu(es->s_feature_incompat) &
5060               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5061                 ext4_msg(sb, KERN_ERR, "external journal has "
5062                                         "bad superblock");
5063                 brelse(bh);
5064                 goto out_bdev;
5065         }
5066
5067         if ((le32_to_cpu(es->s_feature_ro_compat) &
5068              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5069             es->s_checksum != ext4_superblock_csum(sb, es)) {
5070                 ext4_msg(sb, KERN_ERR, "external journal has "
5071                                        "corrupt superblock");
5072                 brelse(bh);
5073                 goto out_bdev;
5074         }
5075
5076         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5077                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5078                 brelse(bh);
5079                 goto out_bdev;
5080         }
5081
5082         len = ext4_blocks_count(es);
5083         start = sb_block + 1;
5084         brelse(bh);     /* we're done with the superblock */
5085
5086         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5087                                         start, len, blocksize);
5088         if (!journal) {
5089                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5090                 goto out_bdev;
5091         }
5092         journal->j_private = sb;
5093         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
5094         wait_on_buffer(journal->j_sb_buffer);
5095         if (!buffer_uptodate(journal->j_sb_buffer)) {
5096                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5097                 goto out_journal;
5098         }
5099         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5100                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5101                                         "user (unsupported) - %d",
5102                         be32_to_cpu(journal->j_superblock->s_nr_users));
5103                 goto out_journal;
5104         }
5105         EXT4_SB(sb)->journal_bdev = bdev;
5106         ext4_init_journal_params(sb, journal);
5107         return journal;
5108
5109 out_journal:
5110         jbd2_journal_destroy(journal);
5111 out_bdev:
5112         ext4_blkdev_put(bdev);
5113         return NULL;
5114 }
5115
5116 static int ext4_load_journal(struct super_block *sb,
5117                              struct ext4_super_block *es,
5118                              unsigned long journal_devnum)
5119 {
5120         journal_t *journal;
5121         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5122         dev_t journal_dev;
5123         int err = 0;
5124         int really_read_only;
5125         int journal_dev_ro;
5126
5127         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5128                 return -EFSCORRUPTED;
5129
5130         if (journal_devnum &&
5131             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5132                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5133                         "numbers have changed");
5134                 journal_dev = new_decode_dev(journal_devnum);
5135         } else
5136                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5137
5138         if (journal_inum && journal_dev) {
5139                 ext4_msg(sb, KERN_ERR,
5140                          "filesystem has both journal inode and journal device!");
5141                 return -EINVAL;
5142         }
5143
5144         if (journal_inum) {
5145                 journal = ext4_get_journal(sb, journal_inum);
5146                 if (!journal)
5147                         return -EINVAL;
5148         } else {
5149                 journal = ext4_get_dev_journal(sb, journal_dev);
5150                 if (!journal)
5151                         return -EINVAL;
5152         }
5153
5154         journal_dev_ro = bdev_read_only(journal->j_dev);
5155         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5156
5157         if (journal_dev_ro && !sb_rdonly(sb)) {
5158                 ext4_msg(sb, KERN_ERR,
5159                          "journal device read-only, try mounting with '-o ro'");
5160                 err = -EROFS;
5161                 goto err_out;
5162         }
5163
5164         /*
5165          * Are we loading a blank journal or performing recovery after a
5166          * crash?  For recovery, we need to check in advance whether we
5167          * can get read-write access to the device.
5168          */
5169         if (ext4_has_feature_journal_needs_recovery(sb)) {
5170                 if (sb_rdonly(sb)) {
5171                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5172                                         "required on readonly filesystem");
5173                         if (really_read_only) {
5174                                 ext4_msg(sb, KERN_ERR, "write access "
5175                                         "unavailable, cannot proceed "
5176                                         "(try mounting with noload)");
5177                                 err = -EROFS;
5178                                 goto err_out;
5179                         }
5180                         ext4_msg(sb, KERN_INFO, "write access will "
5181                                "be enabled during recovery");
5182                 }
5183         }
5184
5185         if (!(journal->j_flags & JBD2_BARRIER))
5186                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5187
5188         if (!ext4_has_feature_journal_needs_recovery(sb))
5189                 err = jbd2_journal_wipe(journal, !really_read_only);
5190         if (!err) {
5191                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5192                 if (save)
5193                         memcpy(save, ((char *) es) +
5194                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5195                 err = jbd2_journal_load(journal);
5196                 if (save)
5197                         memcpy(((char *) es) + EXT4_S_ERR_START,
5198                                save, EXT4_S_ERR_LEN);
5199                 kfree(save);
5200         }
5201
5202         if (err) {
5203                 ext4_msg(sb, KERN_ERR, "error loading journal");
5204                 goto err_out;
5205         }
5206
5207         EXT4_SB(sb)->s_journal = journal;
5208         err = ext4_clear_journal_err(sb, es);
5209         if (err) {
5210                 EXT4_SB(sb)->s_journal = NULL;
5211                 jbd2_journal_destroy(journal);
5212                 return err;
5213         }
5214
5215         if (!really_read_only && journal_devnum &&
5216             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5217                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5218
5219                 /* Make sure we flush the recovery flag to disk. */
5220                 ext4_commit_super(sb, 1);
5221         }
5222
5223         return 0;
5224
5225 err_out:
5226         jbd2_journal_destroy(journal);
5227         return err;
5228 }
5229
5230 static int ext4_commit_super(struct super_block *sb, int sync)
5231 {
5232         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
5233         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5234         int error = 0;
5235
5236         if (!sbh || block_device_ejected(sb))
5237                 return error;
5238
5239         /*
5240          * If the file system is mounted read-only, don't update the
5241          * superblock write time.  This avoids updating the superblock
5242          * write time when we are mounting the root file system
5243          * read/only but we need to replay the journal; at that point,
5244          * for people who are east of GMT and who make their clock
5245          * tick in localtime for Windows bug-for-bug compatibility,
5246          * the clock is set in the future, and this will cause e2fsck
5247          * to complain and force a full file system check.
5248          */
5249         if (!(sb->s_flags & SB_RDONLY))
5250                 ext4_update_tstamp(es, s_wtime);
5251         if (sb->s_bdev->bd_part)
5252                 es->s_kbytes_written =
5253                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5254                             ((part_stat_read(sb->s_bdev->bd_part,
5255                                              sectors[STAT_WRITE]) -
5256                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
5257         else
5258                 es->s_kbytes_written =
5259                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5260         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5261                 ext4_free_blocks_count_set(es,
5262                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5263                                 &EXT4_SB(sb)->s_freeclusters_counter)));
5264         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5265                 es->s_free_inodes_count =
5266                         cpu_to_le32(percpu_counter_sum_positive(
5267                                 &EXT4_SB(sb)->s_freeinodes_counter));
5268         BUFFER_TRACE(sbh, "marking dirty");
5269         ext4_superblock_csum_set(sb);
5270         if (sync)
5271                 lock_buffer(sbh);
5272         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5273                 /*
5274                  * Oh, dear.  A previous attempt to write the
5275                  * superblock failed.  This could happen because the
5276                  * USB device was yanked out.  Or it could happen to
5277                  * be a transient write error and maybe the block will
5278                  * be remapped.  Nothing we can do but to retry the
5279                  * write and hope for the best.
5280                  */
5281                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5282                        "superblock detected");
5283                 clear_buffer_write_io_error(sbh);
5284                 set_buffer_uptodate(sbh);
5285         }
5286         mark_buffer_dirty(sbh);
5287         if (sync) {
5288                 unlock_buffer(sbh);
5289                 error = __sync_dirty_buffer(sbh,
5290                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5291                 if (buffer_write_io_error(sbh)) {
5292                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5293                                "superblock");
5294                         clear_buffer_write_io_error(sbh);
5295                         set_buffer_uptodate(sbh);
5296                 }
5297         }
5298         return error;
5299 }
5300
5301 /*
5302  * Have we just finished recovery?  If so, and if we are mounting (or
5303  * remounting) the filesystem readonly, then we will end up with a
5304  * consistent fs on disk.  Record that fact.
5305  */
5306 static int ext4_mark_recovery_complete(struct super_block *sb,
5307                                        struct ext4_super_block *es)
5308 {
5309         int err;
5310         journal_t *journal = EXT4_SB(sb)->s_journal;
5311
5312         if (!ext4_has_feature_journal(sb)) {
5313                 if (journal != NULL) {
5314                         ext4_error(sb, "Journal got removed while the fs was "
5315                                    "mounted!");
5316                         return -EFSCORRUPTED;
5317                 }
5318                 return 0;
5319         }
5320         jbd2_journal_lock_updates(journal);
5321         err = jbd2_journal_flush(journal);
5322         if (err < 0)
5323                 goto out;
5324
5325         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5326                 ext4_clear_feature_journal_needs_recovery(sb);
5327                 ext4_commit_super(sb, 1);
5328         }
5329 out:
5330         jbd2_journal_unlock_updates(journal);
5331         return err;
5332 }
5333
5334 /*
5335  * If we are mounting (or read-write remounting) a filesystem whose journal
5336  * has recorded an error from a previous lifetime, move that error to the
5337  * main filesystem now.
5338  */
5339 static int ext4_clear_journal_err(struct super_block *sb,
5340                                    struct ext4_super_block *es)
5341 {
5342         journal_t *journal;
5343         int j_errno;
5344         const char *errstr;
5345
5346         if (!ext4_has_feature_journal(sb)) {
5347                 ext4_error(sb, "Journal got removed while the fs was mounted!");
5348                 return -EFSCORRUPTED;
5349         }
5350
5351         journal = EXT4_SB(sb)->s_journal;
5352
5353         /*
5354          * Now check for any error status which may have been recorded in the
5355          * journal by a prior ext4_error() or ext4_abort()
5356          */
5357
5358         j_errno = jbd2_journal_errno(journal);
5359         if (j_errno) {
5360                 char nbuf[16];
5361
5362                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5363                 ext4_warning(sb, "Filesystem error recorded "
5364                              "from previous mount: %s", errstr);
5365                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5366
5367                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5368                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5369                 ext4_commit_super(sb, 1);
5370
5371                 jbd2_journal_clear_err(journal);
5372                 jbd2_journal_update_sb_errno(journal);
5373         }
5374         return 0;
5375 }
5376
5377 /*
5378  * Force the running and committing transactions to commit,
5379  * and wait on the commit.
5380  */
5381 int ext4_force_commit(struct super_block *sb)
5382 {
5383         journal_t *journal;
5384
5385         if (sb_rdonly(sb))
5386                 return 0;
5387
5388         journal = EXT4_SB(sb)->s_journal;
5389         return ext4_journal_force_commit(journal);
5390 }
5391
5392 static int ext4_sync_fs(struct super_block *sb, int wait)
5393 {
5394         int ret = 0;
5395         tid_t target;
5396         bool needs_barrier = false;
5397         struct ext4_sb_info *sbi = EXT4_SB(sb);
5398
5399         if (unlikely(ext4_forced_shutdown(sbi)))
5400                 return 0;
5401
5402         trace_ext4_sync_fs(sb, wait);
5403         flush_workqueue(sbi->rsv_conversion_wq);
5404         /*
5405          * Writeback quota in non-journalled quota case - journalled quota has
5406          * no dirty dquots
5407          */
5408         dquot_writeback_dquots(sb, -1);
5409         /*
5410          * Data writeback is possible w/o journal transaction, so barrier must
5411          * being sent at the end of the function. But we can skip it if
5412          * transaction_commit will do it for us.
5413          */
5414         if (sbi->s_journal) {
5415                 target = jbd2_get_latest_transaction(sbi->s_journal);
5416                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5417                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5418                         needs_barrier = true;
5419
5420                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5421                         if (wait)
5422                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5423                                                            target);
5424                 }
5425         } else if (wait && test_opt(sb, BARRIER))
5426                 needs_barrier = true;
5427         if (needs_barrier) {
5428                 int err;
5429                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL);
5430                 if (!ret)
5431                         ret = err;
5432         }
5433
5434         return ret;
5435 }
5436
5437 /*
5438  * LVM calls this function before a (read-only) snapshot is created.  This
5439  * gives us a chance to flush the journal completely and mark the fs clean.
5440  *
5441  * Note that only this function cannot bring a filesystem to be in a clean
5442  * state independently. It relies on upper layer to stop all data & metadata
5443  * modifications.
5444  */
5445 static int ext4_freeze(struct super_block *sb)
5446 {
5447         int error = 0;
5448         journal_t *journal;
5449
5450         if (sb_rdonly(sb))
5451                 return 0;
5452
5453         journal = EXT4_SB(sb)->s_journal;
5454
5455         if (journal) {
5456                 /* Now we set up the journal barrier. */
5457                 jbd2_journal_lock_updates(journal);
5458
5459                 /*
5460                  * Don't clear the needs_recovery flag if we failed to
5461                  * flush the journal.
5462                  */
5463                 error = jbd2_journal_flush(journal);
5464                 if (error < 0)
5465                         goto out;
5466
5467                 /* Journal blocked and flushed, clear needs_recovery flag. */
5468                 ext4_clear_feature_journal_needs_recovery(sb);
5469         }
5470
5471         error = ext4_commit_super(sb, 1);
5472 out:
5473         if (journal)
5474                 /* we rely on upper layer to stop further updates */
5475                 jbd2_journal_unlock_updates(journal);
5476         return error;
5477 }
5478
5479 /*
5480  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5481  * flag here, even though the filesystem is not technically dirty yet.
5482  */
5483 static int ext4_unfreeze(struct super_block *sb)
5484 {
5485         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5486                 return 0;
5487
5488         if (EXT4_SB(sb)->s_journal) {
5489                 /* Reset the needs_recovery flag before the fs is unlocked. */
5490                 ext4_set_feature_journal_needs_recovery(sb);
5491         }
5492
5493         ext4_commit_super(sb, 1);
5494         return 0;
5495 }
5496
5497 /*
5498  * Structure to save mount options for ext4_remount's benefit
5499  */
5500 struct ext4_mount_options {
5501         unsigned long s_mount_opt;
5502         unsigned long s_mount_opt2;
5503         kuid_t s_resuid;
5504         kgid_t s_resgid;
5505         unsigned long s_commit_interval;
5506         u32 s_min_batch_time, s_max_batch_time;
5507 #ifdef CONFIG_QUOTA
5508         int s_jquota_fmt;
5509         char *s_qf_names[EXT4_MAXQUOTAS];
5510 #endif
5511 };
5512
5513 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5514 {
5515         struct ext4_super_block *es;
5516         struct ext4_sb_info *sbi = EXT4_SB(sb);
5517         unsigned long old_sb_flags, vfs_flags;
5518         struct ext4_mount_options old_opts;
5519         int enable_quota = 0;
5520         ext4_group_t g;
5521         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5522         int err = 0;
5523 #ifdef CONFIG_QUOTA
5524         int i, j;
5525         char *to_free[EXT4_MAXQUOTAS];
5526 #endif
5527         char *orig_data = kstrdup(data, GFP_KERNEL);
5528
5529         if (data && !orig_data)
5530                 return -ENOMEM;
5531
5532         /* Store the original options */
5533         old_sb_flags = sb->s_flags;
5534         old_opts.s_mount_opt = sbi->s_mount_opt;
5535         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5536         old_opts.s_resuid = sbi->s_resuid;
5537         old_opts.s_resgid = sbi->s_resgid;
5538         old_opts.s_commit_interval = sbi->s_commit_interval;
5539         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5540         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5541 #ifdef CONFIG_QUOTA
5542         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5543         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5544                 if (sbi->s_qf_names[i]) {
5545                         char *qf_name = get_qf_name(sb, sbi, i);
5546
5547                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5548                         if (!old_opts.s_qf_names[i]) {
5549                                 for (j = 0; j < i; j++)
5550                                         kfree(old_opts.s_qf_names[j]);
5551                                 kfree(orig_data);
5552                                 return -ENOMEM;
5553                         }
5554                 } else
5555                         old_opts.s_qf_names[i] = NULL;
5556 #endif
5557         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5558                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5559
5560         /*
5561          * Some options can be enabled by ext4 and/or by VFS mount flag
5562          * either way we need to make sure it matches in both *flags and
5563          * s_flags. Copy those selected flags from *flags to s_flags
5564          */
5565         vfs_flags = SB_LAZYTIME | SB_I_VERSION;
5566         sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags);
5567
5568         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5569                 err = -EINVAL;
5570                 goto restore_opts;
5571         }
5572
5573         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5574             test_opt(sb, JOURNAL_CHECKSUM)) {
5575                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5576                          "during remount not supported; ignoring");
5577                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5578         }
5579
5580         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5581                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5582                         ext4_msg(sb, KERN_ERR, "can't mount with "
5583                                  "both data=journal and delalloc");
5584                         err = -EINVAL;
5585                         goto restore_opts;
5586                 }
5587                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5588                         ext4_msg(sb, KERN_ERR, "can't mount with "
5589                                  "both data=journal and dioread_nolock");
5590                         err = -EINVAL;
5591                         goto restore_opts;
5592                 }
5593         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5594                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5595                         ext4_msg(sb, KERN_ERR, "can't mount with "
5596                                 "journal_async_commit in data=ordered mode");
5597                         err = -EINVAL;
5598                         goto restore_opts;
5599                 }
5600         }
5601
5602         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5603                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5604                 err = -EINVAL;
5605                 goto restore_opts;
5606         }
5607
5608         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5609                 ext4_abort(sb, EXT4_ERR_ESHUTDOWN, "Abort forced by user");
5610
5611         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5612                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5613
5614         es = sbi->s_es;
5615
5616         if (sbi->s_journal) {
5617                 ext4_init_journal_params(sb, sbi->s_journal);
5618                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5619         }
5620
5621         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5622                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5623                         err = -EROFS;
5624                         goto restore_opts;
5625                 }
5626
5627                 if (*flags & SB_RDONLY) {
5628                         err = sync_filesystem(sb);
5629                         if (err < 0)
5630                                 goto restore_opts;
5631                         err = dquot_suspend(sb, -1);
5632                         if (err < 0)
5633                                 goto restore_opts;
5634
5635                         /*
5636                          * First of all, the unconditional stuff we have to do
5637                          * to disable replay of the journal when we next remount
5638                          */
5639                         sb->s_flags |= SB_RDONLY;
5640
5641                         /*
5642                          * OK, test if we are remounting a valid rw partition
5643                          * readonly, and if so set the rdonly flag and then
5644                          * mark the partition as valid again.
5645                          */
5646                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5647                             (sbi->s_mount_state & EXT4_VALID_FS))
5648                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5649
5650                         if (sbi->s_journal) {
5651                                 /*
5652                                  * We let remount-ro finish even if marking fs
5653                                  * as clean failed...
5654                                  */
5655                                 ext4_mark_recovery_complete(sb, es);
5656                         }
5657                         if (sbi->s_mmp_tsk)
5658                                 kthread_stop(sbi->s_mmp_tsk);
5659                 } else {
5660                         /* Make sure we can mount this feature set readwrite */
5661                         if (ext4_has_feature_readonly(sb) ||
5662                             !ext4_feature_set_ok(sb, 0)) {
5663                                 err = -EROFS;
5664                                 goto restore_opts;
5665                         }
5666                         /*
5667                          * Make sure the group descriptor checksums
5668                          * are sane.  If they aren't, refuse to remount r/w.
5669                          */
5670                         for (g = 0; g < sbi->s_groups_count; g++) {
5671                                 struct ext4_group_desc *gdp =
5672                                         ext4_get_group_desc(sb, g, NULL);
5673
5674                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5675                                         ext4_msg(sb, KERN_ERR,
5676                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5677                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5678                                                le16_to_cpu(gdp->bg_checksum));
5679                                         err = -EFSBADCRC;
5680                                         goto restore_opts;
5681                                 }
5682                         }
5683
5684                         /*
5685                          * If we have an unprocessed orphan list hanging
5686                          * around from a previously readonly bdev mount,
5687                          * require a full umount/remount for now.
5688                          */
5689                         if (es->s_last_orphan) {
5690                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5691                                        "remount RDWR because of unprocessed "
5692                                        "orphan inode list.  Please "
5693                                        "umount/remount instead");
5694                                 err = -EINVAL;
5695                                 goto restore_opts;
5696                         }
5697
5698                         /*
5699                          * Update the original bdev mapping's wb_err value
5700                          * which could be used to detect the metadata async
5701                          * write error.
5702                          */
5703                         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5704                                                  &sbi->s_bdev_wb_err);
5705
5706                         /*
5707                          * Mounting a RDONLY partition read-write, so reread
5708                          * and store the current valid flag.  (It may have
5709                          * been changed by e2fsck since we originally mounted
5710                          * the partition.)
5711                          */
5712                         if (sbi->s_journal) {
5713                                 err = ext4_clear_journal_err(sb, es);
5714                                 if (err)
5715                                         goto restore_opts;
5716                         }
5717                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5718
5719                         err = ext4_setup_super(sb, es, 0);
5720                         if (err)
5721                                 goto restore_opts;
5722
5723                         sb->s_flags &= ~SB_RDONLY;
5724                         if (ext4_has_feature_mmp(sb))
5725                                 if (ext4_multi_mount_protect(sb,
5726                                                 le64_to_cpu(es->s_mmp_block))) {
5727                                         err = -EROFS;
5728                                         goto restore_opts;
5729                                 }
5730                         enable_quota = 1;
5731                 }
5732         }
5733
5734         /*
5735          * Reinitialize lazy itable initialization thread based on
5736          * current settings
5737          */
5738         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5739                 ext4_unregister_li_request(sb);
5740         else {
5741                 ext4_group_t first_not_zeroed;
5742                 first_not_zeroed = ext4_has_uninit_itable(sb);
5743                 ext4_register_li_request(sb, first_not_zeroed);
5744         }
5745
5746         /*
5747          * Handle creation of system zone data early because it can fail.
5748          * Releasing of existing data is done when we are sure remount will
5749          * succeed.
5750          */
5751         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->system_blks) {
5752                 err = ext4_setup_system_zone(sb);
5753                 if (err)
5754                         goto restore_opts;
5755         }
5756
5757         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5758                 err = ext4_commit_super(sb, 1);
5759                 if (err)
5760                         goto restore_opts;
5761         }
5762
5763 #ifdef CONFIG_QUOTA
5764         /* Release old quota file names */
5765         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5766                 kfree(old_opts.s_qf_names[i]);
5767         if (enable_quota) {
5768                 if (sb_any_quota_suspended(sb))
5769                         dquot_resume(sb, -1);
5770                 else if (ext4_has_feature_quota(sb)) {
5771                         err = ext4_enable_quotas(sb);
5772                         if (err)
5773                                 goto restore_opts;
5774                 }
5775         }
5776 #endif
5777         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->system_blks)
5778                 ext4_release_system_zone(sb);
5779
5780         /*
5781          * Some options can be enabled by ext4 and/or by VFS mount flag
5782          * either way we need to make sure it matches in both *flags and
5783          * s_flags. Copy those selected flags from s_flags to *flags
5784          */
5785         *flags = (*flags & ~vfs_flags) | (sb->s_flags & vfs_flags);
5786
5787         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5788         kfree(orig_data);
5789         return 0;
5790
5791 restore_opts:
5792         sb->s_flags = old_sb_flags;
5793         sbi->s_mount_opt = old_opts.s_mount_opt;
5794         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5795         sbi->s_resuid = old_opts.s_resuid;
5796         sbi->s_resgid = old_opts.s_resgid;
5797         sbi->s_commit_interval = old_opts.s_commit_interval;
5798         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5799         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5800         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->system_blks)
5801                 ext4_release_system_zone(sb);
5802 #ifdef CONFIG_QUOTA
5803         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5804         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5805                 to_free[i] = get_qf_name(sb, sbi, i);
5806                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
5807         }
5808         synchronize_rcu();
5809         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5810                 kfree(to_free[i]);
5811 #endif
5812         kfree(orig_data);
5813         return err;
5814 }
5815
5816 #ifdef CONFIG_QUOTA
5817 static int ext4_statfs_project(struct super_block *sb,
5818                                kprojid_t projid, struct kstatfs *buf)
5819 {
5820         struct kqid qid;
5821         struct dquot *dquot;
5822         u64 limit;
5823         u64 curblock;
5824
5825         qid = make_kqid_projid(projid);
5826         dquot = dqget(sb, qid);
5827         if (IS_ERR(dquot))
5828                 return PTR_ERR(dquot);
5829         spin_lock(&dquot->dq_dqb_lock);
5830
5831         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
5832                              dquot->dq_dqb.dqb_bhardlimit);
5833         limit >>= sb->s_blocksize_bits;
5834
5835         if (limit && buf->f_blocks > limit) {
5836                 curblock = (dquot->dq_dqb.dqb_curspace +
5837                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5838                 buf->f_blocks = limit;
5839                 buf->f_bfree = buf->f_bavail =
5840                         (buf->f_blocks > curblock) ?
5841                          (buf->f_blocks - curblock) : 0;
5842         }
5843
5844         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
5845                              dquot->dq_dqb.dqb_ihardlimit);
5846         if (limit && buf->f_files > limit) {
5847                 buf->f_files = limit;
5848                 buf->f_ffree =
5849                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5850                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5851         }
5852
5853         spin_unlock(&dquot->dq_dqb_lock);
5854         dqput(dquot);
5855         return 0;
5856 }
5857 #endif
5858
5859 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5860 {
5861         struct super_block *sb = dentry->d_sb;
5862         struct ext4_sb_info *sbi = EXT4_SB(sb);
5863         struct ext4_super_block *es = sbi->s_es;
5864         ext4_fsblk_t overhead = 0, resv_blocks;
5865         u64 fsid;
5866         s64 bfree;
5867         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5868
5869         if (!test_opt(sb, MINIX_DF))
5870                 overhead = sbi->s_overhead;
5871
5872         buf->f_type = EXT4_SUPER_MAGIC;
5873         buf->f_bsize = sb->s_blocksize;
5874         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5875         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5876                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5877         /* prevent underflow in case that few free space is available */
5878         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5879         buf->f_bavail = buf->f_bfree -
5880                         (ext4_r_blocks_count(es) + resv_blocks);
5881         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5882                 buf->f_bavail = 0;
5883         buf->f_files = le32_to_cpu(es->s_inodes_count);
5884         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5885         buf->f_namelen = EXT4_NAME_LEN;
5886         fsid = le64_to_cpup((void *)es->s_uuid) ^
5887                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5888         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5889         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5890
5891 #ifdef CONFIG_QUOTA
5892         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5893             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5894                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5895 #endif
5896         return 0;
5897 }
5898
5899
5900 #ifdef CONFIG_QUOTA
5901
5902 /*
5903  * Helper functions so that transaction is started before we acquire dqio_sem
5904  * to keep correct lock ordering of transaction > dqio_sem
5905  */
5906 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5907 {
5908         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5909 }
5910
5911 static int ext4_write_dquot(struct dquot *dquot)
5912 {
5913         int ret, err;
5914         handle_t *handle;
5915         struct inode *inode;
5916
5917         inode = dquot_to_inode(dquot);
5918         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5919                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5920         if (IS_ERR(handle))
5921                 return PTR_ERR(handle);
5922         ret = dquot_commit(dquot);
5923         err = ext4_journal_stop(handle);
5924         if (!ret)
5925                 ret = err;
5926         return ret;
5927 }
5928
5929 static int ext4_acquire_dquot(struct dquot *dquot)
5930 {
5931         int ret, err;
5932         handle_t *handle;
5933
5934         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5935                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5936         if (IS_ERR(handle))
5937                 return PTR_ERR(handle);
5938         ret = dquot_acquire(dquot);
5939         err = ext4_journal_stop(handle);
5940         if (!ret)
5941                 ret = err;
5942         return ret;
5943 }
5944
5945 static int ext4_release_dquot(struct dquot *dquot)
5946 {
5947         int ret, err;
5948         handle_t *handle;
5949
5950         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5951                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5952         if (IS_ERR(handle)) {
5953                 /* Release dquot anyway to avoid endless cycle in dqput() */
5954                 dquot_release(dquot);
5955                 return PTR_ERR(handle);
5956         }
5957         ret = dquot_release(dquot);
5958         err = ext4_journal_stop(handle);
5959         if (!ret)
5960                 ret = err;
5961         return ret;
5962 }
5963
5964 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5965 {
5966         struct super_block *sb = dquot->dq_sb;
5967         struct ext4_sb_info *sbi = EXT4_SB(sb);
5968
5969         /* Are we journaling quotas? */
5970         if (ext4_has_feature_quota(sb) ||
5971             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5972                 dquot_mark_dquot_dirty(dquot);
5973                 return ext4_write_dquot(dquot);
5974         } else {
5975                 return dquot_mark_dquot_dirty(dquot);
5976         }
5977 }
5978
5979 static int ext4_write_info(struct super_block *sb, int type)
5980 {
5981         int ret, err;
5982         handle_t *handle;
5983
5984         /* Data block + inode block */
5985         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5986         if (IS_ERR(handle))
5987                 return PTR_ERR(handle);
5988         ret = dquot_commit_info(sb, type);
5989         err = ext4_journal_stop(handle);
5990         if (!ret)
5991                 ret = err;
5992         return ret;
5993 }
5994
5995 /*
5996  * Turn on quotas during mount time - we need to find
5997  * the quota file and such...
5998  */
5999 static int ext4_quota_on_mount(struct super_block *sb, int type)
6000 {
6001         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
6002                                         EXT4_SB(sb)->s_jquota_fmt, type);
6003 }
6004
6005 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6006 {
6007         struct ext4_inode_info *ei = EXT4_I(inode);
6008
6009         /* The first argument of lockdep_set_subclass has to be
6010          * *exactly* the same as the argument to init_rwsem() --- in
6011          * this case, in init_once() --- or lockdep gets unhappy
6012          * because the name of the lock is set using the
6013          * stringification of the argument to init_rwsem().
6014          */
6015         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6016         lockdep_set_subclass(&ei->i_data_sem, subclass);
6017 }
6018
6019 /*
6020  * Standard function to be called on quota_on
6021  */
6022 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6023                          const struct path *path)
6024 {
6025         int err;
6026
6027         if (!test_opt(sb, QUOTA))
6028                 return -EINVAL;
6029
6030         /* Quotafile not on the same filesystem? */
6031         if (path->dentry->d_sb != sb)
6032                 return -EXDEV;
6033         /* Journaling quota? */
6034         if (EXT4_SB(sb)->s_qf_names[type]) {
6035                 /* Quotafile not in fs root? */
6036                 if (path->dentry->d_parent != sb->s_root)
6037                         ext4_msg(sb, KERN_WARNING,
6038                                 "Quota file not on filesystem root. "
6039                                 "Journaled quota will not work");
6040                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6041         } else {
6042                 /*
6043                  * Clear the flag just in case mount options changed since
6044                  * last time.
6045                  */
6046                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6047         }
6048
6049         /*
6050          * When we journal data on quota file, we have to flush journal to see
6051          * all updates to the file when we bypass pagecache...
6052          */
6053         if (EXT4_SB(sb)->s_journal &&
6054             ext4_should_journal_data(d_inode(path->dentry))) {
6055                 /*
6056                  * We don't need to lock updates but journal_flush() could
6057                  * otherwise be livelocked...
6058                  */
6059                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6060                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
6061                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6062                 if (err)
6063                         return err;
6064         }
6065
6066         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6067         err = dquot_quota_on(sb, type, format_id, path);
6068         if (err) {
6069                 lockdep_set_quota_inode(path->dentry->d_inode,
6070                                              I_DATA_SEM_NORMAL);
6071         } else {
6072                 struct inode *inode = d_inode(path->dentry);
6073                 handle_t *handle;
6074
6075                 /*
6076                  * Set inode flags to prevent userspace from messing with quota
6077                  * files. If this fails, we return success anyway since quotas
6078                  * are already enabled and this is not a hard failure.
6079                  */
6080                 inode_lock(inode);
6081                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6082                 if (IS_ERR(handle))
6083                         goto unlock_inode;
6084                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6085                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6086                                 S_NOATIME | S_IMMUTABLE);
6087                 err = ext4_mark_inode_dirty(handle, inode);
6088                 ext4_journal_stop(handle);
6089         unlock_inode:
6090                 inode_unlock(inode);
6091         }
6092         return err;
6093 }
6094
6095 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6096                              unsigned int flags)
6097 {
6098         int err;
6099         struct inode *qf_inode;
6100         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6101                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6102                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6103                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6104         };
6105
6106         BUG_ON(!ext4_has_feature_quota(sb));
6107
6108         if (!qf_inums[type])
6109                 return -EPERM;
6110
6111         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6112         if (IS_ERR(qf_inode)) {
6113                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6114                 return PTR_ERR(qf_inode);
6115         }
6116
6117         /* Don't account quota for quota files to avoid recursion */
6118         qf_inode->i_flags |= S_NOQUOTA;
6119         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6120         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6121         if (err)
6122                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6123         iput(qf_inode);
6124
6125         return err;
6126 }
6127
6128 /* Enable usage tracking for all quota types. */
6129 static int ext4_enable_quotas(struct super_block *sb)
6130 {
6131         int type, err = 0;
6132         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6133                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6134                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6135                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6136         };
6137         bool quota_mopt[EXT4_MAXQUOTAS] = {
6138                 test_opt(sb, USRQUOTA),
6139                 test_opt(sb, GRPQUOTA),
6140                 test_opt(sb, PRJQUOTA),
6141         };
6142
6143         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6144         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6145                 if (qf_inums[type]) {
6146                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6147                                 DQUOT_USAGE_ENABLED |
6148                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6149                         if (err) {
6150                                 ext4_warning(sb,
6151                                         "Failed to enable quota tracking "
6152                                         "(type=%d, err=%d). Please run "
6153                                         "e2fsck to fix.", type, err);
6154                                 for (type--; type >= 0; type--)
6155                                         dquot_quota_off(sb, type);
6156
6157                                 return err;
6158                         }
6159                 }
6160         }
6161         return 0;
6162 }
6163
6164 static int ext4_quota_off(struct super_block *sb, int type)
6165 {
6166         struct inode *inode = sb_dqopt(sb)->files[type];
6167         handle_t *handle;
6168         int err;
6169
6170         /* Force all delayed allocation blocks to be allocated.
6171          * Caller already holds s_umount sem */
6172         if (test_opt(sb, DELALLOC))
6173                 sync_filesystem(sb);
6174
6175         if (!inode || !igrab(inode))
6176                 goto out;
6177
6178         err = dquot_quota_off(sb, type);
6179         if (err || ext4_has_feature_quota(sb))
6180                 goto out_put;
6181
6182         inode_lock(inode);
6183         /*
6184          * Update modification times of quota files when userspace can
6185          * start looking at them. If we fail, we return success anyway since
6186          * this is not a hard failure and quotas are already disabled.
6187          */
6188         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6189         if (IS_ERR(handle)) {
6190                 err = PTR_ERR(handle);
6191                 goto out_unlock;
6192         }
6193         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6194         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6195         inode->i_mtime = inode->i_ctime = current_time(inode);
6196         err = ext4_mark_inode_dirty(handle, inode);
6197         ext4_journal_stop(handle);
6198 out_unlock:
6199         inode_unlock(inode);
6200 out_put:
6201         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6202         iput(inode);
6203         return err;
6204 out:
6205         return dquot_quota_off(sb, type);
6206 }
6207
6208 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6209  * acquiring the locks... As quota files are never truncated and quota code
6210  * itself serializes the operations (and no one else should touch the files)
6211  * we don't have to be afraid of races */
6212 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6213                                size_t len, loff_t off)
6214 {
6215         struct inode *inode = sb_dqopt(sb)->files[type];
6216         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6217         int offset = off & (sb->s_blocksize - 1);
6218         int tocopy;
6219         size_t toread;
6220         struct buffer_head *bh;
6221         loff_t i_size = i_size_read(inode);
6222
6223         if (off > i_size)
6224                 return 0;
6225         if (off+len > i_size)
6226                 len = i_size-off;
6227         toread = len;
6228         while (toread > 0) {
6229                 tocopy = sb->s_blocksize - offset < toread ?
6230                                 sb->s_blocksize - offset : toread;
6231                 bh = ext4_bread(NULL, inode, blk, 0);
6232                 if (IS_ERR(bh))
6233                         return PTR_ERR(bh);
6234                 if (!bh)        /* A hole? */
6235                         memset(data, 0, tocopy);
6236                 else
6237                         memcpy(data, bh->b_data+offset, tocopy);
6238                 brelse(bh);
6239                 offset = 0;
6240                 toread -= tocopy;
6241                 data += tocopy;
6242                 blk++;
6243         }
6244         return len;
6245 }
6246
6247 /* Write to quotafile (we know the transaction is already started and has
6248  * enough credits) */
6249 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6250                                 const char *data, size_t len, loff_t off)
6251 {
6252         struct inode *inode = sb_dqopt(sb)->files[type];
6253         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6254         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6255         int retries = 0;
6256         struct buffer_head *bh;
6257         handle_t *handle = journal_current_handle();
6258
6259         if (EXT4_SB(sb)->s_journal && !handle) {
6260                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6261                         " cancelled because transaction is not started",
6262                         (unsigned long long)off, (unsigned long long)len);
6263                 return -EIO;
6264         }
6265         /*
6266          * Since we account only one data block in transaction credits,
6267          * then it is impossible to cross a block boundary.
6268          */
6269         if (sb->s_blocksize - offset < len) {
6270                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6271                         " cancelled because not block aligned",
6272                         (unsigned long long)off, (unsigned long long)len);
6273                 return -EIO;
6274         }
6275
6276         do {
6277                 bh = ext4_bread(handle, inode, blk,
6278                                 EXT4_GET_BLOCKS_CREATE |
6279                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6280         } while (PTR_ERR(bh) == -ENOSPC &&
6281                  ext4_should_retry_alloc(inode->i_sb, &retries));
6282         if (IS_ERR(bh))
6283                 return PTR_ERR(bh);
6284         if (!bh)
6285                 goto out;
6286         BUFFER_TRACE(bh, "get write access");
6287         err = ext4_journal_get_write_access(handle, bh);
6288         if (err) {
6289                 brelse(bh);
6290                 return err;
6291         }
6292         lock_buffer(bh);
6293         memcpy(bh->b_data+offset, data, len);
6294         flush_dcache_page(bh->b_page);
6295         unlock_buffer(bh);
6296         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6297         brelse(bh);
6298 out:
6299         if (inode->i_size < off + len) {
6300                 i_size_write(inode, off + len);
6301                 EXT4_I(inode)->i_disksize = inode->i_size;
6302                 err2 = ext4_mark_inode_dirty(handle, inode);
6303                 if (unlikely(err2 && !err))
6304                         err = err2;
6305         }
6306         return err ? err : len;
6307 }
6308 #endif
6309
6310 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6311                        const char *dev_name, void *data)
6312 {
6313         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6314 }
6315
6316 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6317 static inline void register_as_ext2(void)
6318 {
6319         int err = register_filesystem(&ext2_fs_type);
6320         if (err)
6321                 printk(KERN_WARNING
6322                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6323 }
6324
6325 static inline void unregister_as_ext2(void)
6326 {
6327         unregister_filesystem(&ext2_fs_type);
6328 }
6329
6330 static inline int ext2_feature_set_ok(struct super_block *sb)
6331 {
6332         if (ext4_has_unknown_ext2_incompat_features(sb))
6333                 return 0;
6334         if (sb_rdonly(sb))
6335                 return 1;
6336         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6337                 return 0;
6338         return 1;
6339 }
6340 #else
6341 static inline void register_as_ext2(void) { }
6342 static inline void unregister_as_ext2(void) { }
6343 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6344 #endif
6345
6346 static inline void register_as_ext3(void)
6347 {
6348         int err = register_filesystem(&ext3_fs_type);
6349         if (err)
6350                 printk(KERN_WARNING
6351                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6352 }
6353
6354 static inline void unregister_as_ext3(void)
6355 {
6356         unregister_filesystem(&ext3_fs_type);
6357 }
6358
6359 static inline int ext3_feature_set_ok(struct super_block *sb)
6360 {
6361         if (ext4_has_unknown_ext3_incompat_features(sb))
6362                 return 0;
6363         if (!ext4_has_feature_journal(sb))
6364                 return 0;
6365         if (sb_rdonly(sb))
6366                 return 1;
6367         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6368                 return 0;
6369         return 1;
6370 }
6371
6372 static struct file_system_type ext4_fs_type = {
6373         .owner          = THIS_MODULE,
6374         .name           = "ext4",
6375         .mount          = ext4_mount,
6376         .kill_sb        = kill_block_super,
6377         .fs_flags       = FS_REQUIRES_DEV,
6378 };
6379 MODULE_ALIAS_FS("ext4");
6380
6381 /* Shared across all ext4 file systems */
6382 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6383
6384 static int __init ext4_init_fs(void)
6385 {
6386         int i, err;
6387
6388         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6389         ext4_li_info = NULL;
6390         mutex_init(&ext4_li_mtx);
6391
6392         /* Build-time check for flags consistency */
6393         ext4_check_flag_values();
6394
6395         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6396                 init_waitqueue_head(&ext4__ioend_wq[i]);
6397
6398         err = ext4_init_es();
6399         if (err)
6400                 return err;
6401
6402         err = ext4_init_pending();
6403         if (err)
6404                 goto out7;
6405
6406         err = ext4_init_post_read_processing();
6407         if (err)
6408                 goto out6;
6409
6410         err = ext4_init_pageio();
6411         if (err)
6412                 goto out5;
6413
6414         err = ext4_init_system_zone();
6415         if (err)
6416                 goto out4;
6417
6418         err = ext4_init_sysfs();
6419         if (err)
6420                 goto out3;
6421
6422         err = ext4_init_mballoc();
6423         if (err)
6424                 goto out2;
6425         err = init_inodecache();
6426         if (err)
6427                 goto out1;
6428         register_as_ext3();
6429         register_as_ext2();
6430         err = register_filesystem(&ext4_fs_type);
6431         if (err)
6432                 goto out;
6433
6434         return 0;
6435 out:
6436         unregister_as_ext2();
6437         unregister_as_ext3();
6438         destroy_inodecache();
6439 out1:
6440         ext4_exit_mballoc();
6441 out2:
6442         ext4_exit_sysfs();
6443 out3:
6444         ext4_exit_system_zone();
6445 out4:
6446         ext4_exit_pageio();
6447 out5:
6448         ext4_exit_post_read_processing();
6449 out6:
6450         ext4_exit_pending();
6451 out7:
6452         ext4_exit_es();
6453
6454         return err;
6455 }
6456
6457 static void __exit ext4_exit_fs(void)
6458 {
6459         ext4_destroy_lazyinit_thread();
6460         unregister_as_ext2();
6461         unregister_as_ext3();
6462         unregister_filesystem(&ext4_fs_type);
6463         destroy_inodecache();
6464         ext4_exit_mballoc();
6465         ext4_exit_sysfs();
6466         ext4_exit_system_zone();
6467         ext4_exit_pageio();
6468         ext4_exit_post_read_processing();
6469         ext4_exit_es();
6470         ext4_exit_pending();
6471 }
6472
6473 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6474 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6475 MODULE_LICENSE("GPL");
6476 MODULE_SOFTDEP("pre: crc32c");
6477 module_init(ext4_init_fs)
6478 module_exit(ext4_exit_fs)