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         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 748                 return;
 749
 750         va_start(args, fmt);
 751         vaf.fmt = fmt;
 752         vaf.va = &args;
 753         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 754         va_end(args);
 755 }
 756
 757 #define ext4_warning_ratelimit(sb)                                      \
 758                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 759                              "EXT4-fs warning")
 760
 761 void __ext4_warning(struct super_block *sb, const char *function,
 762                     unsigned int line, const char *fmt, ...)
 763 {
 764         struct va_format vaf;
 765         va_list args;
 766
 767         if (!ext4_warning_ratelimit(sb))
 768                 return;
 769
 770         va_start(args, fmt);
 771         vaf.fmt = fmt;
 772         vaf.va = &args;
 773         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 774                sb->s_id, function, line, &vaf);
 775         va_end(args);
 776 }
 777
 778 void __ext4_warning_inode(const struct inode *inode, const char *function,
 779                           unsigned int line, const char *fmt, ...)
 780 {
 781         struct va_format vaf;
 782         va_list args;
 783
 784         if (!ext4_warning_ratelimit(inode->i_sb))
 785                 return;
 786
 787         va_start(args, fmt);
 788         vaf.fmt = fmt;
 789         vaf.va = &args;
 790         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 791                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 792                function, line, inode->i_ino, current->comm, &vaf);
 793         va_end(args);
 794 }
 795
 796 void __ext4_grp_locked_error(const char *function, unsigned int line,
 797                              struct super_block *sb, ext4_group_t grp,
 798                              unsigned long ino, ext4_fsblk_t block,
 799                              const char *fmt, ...)
 800 __releases(bitlock)
 801 __acquires(bitlock)
 802 {
 803         struct va_format vaf;
 804         va_list args;
 805
 806         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 807                 return;
 808
 809         trace_ext4_error(sb, function, line);
 810         __save_error_info(sb, EFSCORRUPTED, ino, block, function, line);
 811
 812         if (ext4_error_ratelimit(sb)) {
 813                 va_start(args, fmt);
 814                 vaf.fmt = fmt;
 815                 vaf.va = &args;
 816                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 817                        sb->s_id, function, line, grp);
 818                 if (ino)
 819                         printk(KERN_CONT "inode %lu: ", ino);
 820                 if (block)
 821                         printk(KERN_CONT "block %llu:",
 822                                (unsigned long long) block);
 823                 printk(KERN_CONT "%pV\n", &vaf);
 824                 va_end(args);
 825         }
 826
 827         if (test_opt(sb, WARN_ON_ERROR))
 828                 WARN_ON_ONCE(1);
 829
 830         if (test_opt(sb, ERRORS_CONT)) {
 831                 ext4_commit_super(sb, 0);
 832                 return;
 833         }
 834
 835         ext4_unlock_group(sb, grp);
 836         ext4_commit_super(sb, 1);
 837         ext4_handle_error(sb);
 838         /*
 839          * We only get here in the ERRORS_RO case; relocking the group
 840          * may be dangerous, but nothing bad will happen since the
 841          * filesystem will have already been marked read/only and the
 842          * journal has been aborted.  We return 1 as a hint to callers
 843          * who might what to use the return value from
 844          * ext4_grp_locked_error() to distinguish between the
 845          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 846          * aggressively from the ext4 function in question, with a
 847          * more appropriate error code.
 848          */
 849         ext4_lock_group(sb, grp);
 850         return;
 851 }
 852
 853 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
 854                                      ext4_group_t group,
 855                                      unsigned int flags)
 856 {
 857         struct ext4_sb_info *sbi = EXT4_SB(sb);
 858         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
 859         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
 860         int ret;
 861
 862         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
 863                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
 864                                             &grp->bb_state);
 865                 if (!ret)
 866                         percpu_counter_sub(&sbi->s_freeclusters_counter,
 867                                            grp->bb_free);
 868         }
 869
 870         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
 871                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
 872                                             &grp->bb_state);
 873                 if (!ret && gdp) {
 874                         int count;
 875
 876                         count = ext4_free_inodes_count(sb, gdp);
 877                         percpu_counter_sub(&sbi->s_freeinodes_counter,
 878                                            count);
 879                 }
 880         }
 881 }
 882
 883 void ext4_update_dynamic_rev(struct super_block *sb)
 884 {
 885         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 886
 887         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 888                 return;
 889
 890         ext4_warning(sb,
 891                      "updating to rev %d because of new feature flag, "
 892                      "running e2fsck is recommended",
 893                      EXT4_DYNAMIC_REV);
 894
 895         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 896         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 897         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 898         /* leave es->s_feature_*compat flags alone */
 899         /* es->s_uuid will be set by e2fsck if empty */
 900
 901         /*
 902          * The rest of the superblock fields should be zero, and if not it
 903          * means they are likely already in use, so leave them alone.  We
 904          * can leave it up to e2fsck to clean up any inconsistencies there.
 905          */
 906 }
 907
 908 /*
 909  * Open the external journal device
 910  */
 911 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 912 {
 913         struct block_device *bdev;
 914
 915         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 916         if (IS_ERR(bdev))
 917                 goto fail;
 918         return bdev;
 919
 920 fail:
 921         ext4_msg(sb, KERN_ERR,
 922                  "failed to open journal device unknown-block(%u,%u) %ld",
 923                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
 924         return NULL;
 925 }
 926
 927 /*
 928  * Release the journal device
 929  */
 930 static void ext4_blkdev_put(struct block_device *bdev)
 931 {
 932         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 933 }
 934
 935 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 936 {
 937         struct block_device *bdev;
 938         bdev = sbi->journal_bdev;
 939         if (bdev) {
 940                 ext4_blkdev_put(bdev);
 941                 sbi->journal_bdev = NULL;
 942         }
 943 }
 944
 945 static inline struct inode *orphan_list_entry(struct list_head *l)
 946 {
 947         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 948 }
 949
 950 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 951 {
 952         struct list_head *l;
 953
 954         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 955                  le32_to_cpu(sbi->s_es->s_last_orphan));
 956
 957         printk(KERN_ERR "sb_info orphan list:\n");
 958         list_for_each(l, &sbi->s_orphan) {
 959                 struct inode *inode = orphan_list_entry(l);
 960                 printk(KERN_ERR "  "
 961                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 962                        inode->i_sb->s_id, inode->i_ino, inode,
 963                        inode->i_mode, inode->i_nlink,
 964                        NEXT_ORPHAN(inode));
 965         }
 966 }
 967
 968 #ifdef CONFIG_QUOTA
 969 static int ext4_quota_off(struct super_block *sb, int type);
 970
 971 static inline void ext4_quota_off_umount(struct super_block *sb)
 972 {
 973         int type;
 974
 975         /* Use our quota_off function to clear inode flags etc. */
 976         for (type = 0; type < EXT4_MAXQUOTAS; type++)
 977                 ext4_quota_off(sb, type);
 978 }
 979
 980 /*
 981  * This is a helper function which is used in the mount/remount
 982  * codepaths (which holds s_umount) to fetch the quota file name.
 983  */
 984 static inline char *get_qf_name(struct super_block *sb,
 985                                 struct ext4_sb_info *sbi,
 986                                 int type)
 987 {
 988         return rcu_dereference_protected(sbi->s_qf_names[type],
 989                                          lockdep_is_held(&sb->s_umount));
 990 }
 991 #else
 992 static inline void ext4_quota_off_umount(struct super_block *sb)
 993 {
 994 }
 995 #endif
 996
 997 static void ext4_put_super(struct super_block *sb)
 998 {
 999         struct ext4_sb_info *sbi = EXT4_SB(sb);
1000         struct ext4_super_block *es = sbi->s_es;
1001         struct buffer_head **group_desc;
1002         struct flex_groups **flex_groups;
1003         int aborted = 0;
1004         int i, err;
1005
1006         ext4_unregister_li_request(sb);
1007         ext4_quota_off_umount(sb);
1008
1009         destroy_workqueue(sbi->rsv_conversion_wq);
1010
1011         /*
1012          * Unregister sysfs before destroying jbd2 journal.
1013          * Since we could still access attr_journal_task attribute via sysfs
1014          * path which could have sbi->s_journal->j_task as NULL
1015          */
1016         ext4_unregister_sysfs(sb);
1017
1018         if (sbi->s_journal) {
1019                 aborted = is_journal_aborted(sbi->s_journal);
1020                 err = jbd2_journal_destroy(sbi->s_journal);
1021                 sbi->s_journal = NULL;
1022                 if ((err < 0) && !aborted) {
1023                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1024                 }
1025         }
1026
1027         ext4_es_unregister_shrinker(sbi);
1028         del_timer_sync(&sbi->s_err_report);
1029         ext4_release_system_zone(sb);
1030         ext4_mb_release(sb);
1031         ext4_ext_release(sb);
1032
1033         if (!sb_rdonly(sb) && !aborted) {
1034                 ext4_clear_feature_journal_needs_recovery(sb);
1035                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1036         }
1037         if (!sb_rdonly(sb))
1038                 ext4_commit_super(sb, 1);
1039
1040         rcu_read_lock();
1041         group_desc = rcu_dereference(sbi->s_group_desc);
1042         for (i = 0; i < sbi->s_gdb_count; i++)
1043                 brelse(group_desc[i]);
1044         kvfree(group_desc);
1045         flex_groups = rcu_dereference(sbi->s_flex_groups);
1046         if (flex_groups) {
1047                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1048                         kvfree(flex_groups[i]);
1049                 kvfree(flex_groups);
1050         }
1051         rcu_read_unlock();
1052         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1053         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1054         percpu_counter_destroy(&sbi->s_dirs_counter);
1055         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1056         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1057 #ifdef CONFIG_QUOTA
1058         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1059                 kfree(get_qf_name(sb, sbi, i));
1060 #endif
1061
1062         /* Debugging code just in case the in-memory inode orphan list
1063          * isn't empty.  The on-disk one can be non-empty if we've
1064          * detected an error and taken the fs readonly, but the
1065          * in-memory list had better be clean by this point. */
1066         if (!list_empty(&sbi->s_orphan))
1067                 dump_orphan_list(sb, sbi);
1068         J_ASSERT(list_empty(&sbi->s_orphan));
1069
1070         sync_blockdev(sb->s_bdev);
1071         invalidate_bdev(sb->s_bdev);
1072         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
1073                 /*
1074                  * Invalidate the journal device's buffers.  We don't want them
1075                  * floating about in memory - the physical journal device may
1076                  * hotswapped, and it breaks the `ro-after' testing code.
1077                  */
1078                 sync_blockdev(sbi->journal_bdev);
1079                 invalidate_bdev(sbi->journal_bdev);
1080                 ext4_blkdev_remove(sbi);
1081         }
1082
1083         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1084         sbi->s_ea_inode_cache = NULL;
1085
1086         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1087         sbi->s_ea_block_cache = NULL;
1088
1089         if (sbi->s_mmp_tsk)
1090                 kthread_stop(sbi->s_mmp_tsk);
1091         brelse(sbi->s_sbh);
1092         sb->s_fs_info = NULL;
1093         /*
1094          * Now that we are completely done shutting down the
1095          * superblock, we need to actually destroy the kobject.
1096          */
1097         kobject_put(&sbi->s_kobj);
1098         wait_for_completion(&sbi->s_kobj_unregister);
1099         if (sbi->s_chksum_driver)
1100                 crypto_free_shash(sbi->s_chksum_driver);
1101         kfree(sbi->s_blockgroup_lock);
1102         fs_put_dax(sbi->s_daxdev);
1103         fscrypt_free_dummy_context(&sbi->s_dummy_enc_ctx);
1104 #ifdef CONFIG_UNICODE
1105         utf8_unload(sbi->s_encoding);
1106 #endif
1107         kfree(sbi);
1108 }
1109
1110 static struct kmem_cache *ext4_inode_cachep;
1111
1112 /*
1113  * Called inside transaction, so use GFP_NOFS
1114  */
1115 static struct inode *ext4_alloc_inode(struct super_block *sb)
1116 {
1117         struct ext4_inode_info *ei;
1118
1119         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1120         if (!ei)
1121                 return NULL;
1122
1123         inode_set_iversion(&ei->vfs_inode, 1);
1124         spin_lock_init(&ei->i_raw_lock);
1125         INIT_LIST_HEAD(&ei->i_prealloc_list);
1126         spin_lock_init(&ei->i_prealloc_lock);
1127         ext4_es_init_tree(&ei->i_es_tree);
1128         rwlock_init(&ei->i_es_lock);
1129         INIT_LIST_HEAD(&ei->i_es_list);
1130         ei->i_es_all_nr = 0;
1131         ei->i_es_shk_nr = 0;
1132         ei->i_es_shrink_lblk = 0;
1133         ei->i_reserved_data_blocks = 0;
1134         spin_lock_init(&(ei->i_block_reservation_lock));
1135         ext4_init_pending_tree(&ei->i_pending_tree);
1136 #ifdef CONFIG_QUOTA
1137         ei->i_reserved_quota = 0;
1138         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1139 #endif
1140         ei->jinode = NULL;
1141         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1142         spin_lock_init(&ei->i_completed_io_lock);
1143         ei->i_sync_tid = 0;
1144         ei->i_datasync_tid = 0;
1145         atomic_set(&ei->i_unwritten, 0);
1146         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1147         return &ei->vfs_inode;
1148 }
1149
1150 static int ext4_drop_inode(struct inode *inode)
1151 {
1152         int drop = generic_drop_inode(inode);
1153
1154         if (!drop)
1155                 drop = fscrypt_drop_inode(inode);
1156
1157         trace_ext4_drop_inode(inode, drop);
1158         return drop;
1159 }
1160
1161 static void ext4_free_in_core_inode(struct inode *inode)
1162 {
1163         fscrypt_free_inode(inode);
1164         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1165 }
1166
1167 static void ext4_destroy_inode(struct inode *inode)
1168 {
1169         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1170                 ext4_msg(inode->i_sb, KERN_ERR,
1171                          "Inode %lu (%p): orphan list check failed!",
1172                          inode->i_ino, EXT4_I(inode));
1173                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1174                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1175                                 true);
1176                 dump_stack();
1177         }
1178 }
1179
1180 static void init_once(void *foo)
1181 {
1182         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1183
1184         INIT_LIST_HEAD(&ei->i_orphan);
1185         init_rwsem(&ei->xattr_sem);
1186         init_rwsem(&ei->i_data_sem);
1187         init_rwsem(&ei->i_mmap_sem);
1188         inode_init_once(&ei->vfs_inode);
1189 }
1190
1191 static int __init init_inodecache(void)
1192 {
1193         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1194                                 sizeof(struct ext4_inode_info), 0,
1195                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1196                                         SLAB_ACCOUNT),
1197                                 offsetof(struct ext4_inode_info, i_data),
1198                                 sizeof_field(struct ext4_inode_info, i_data),
1199                                 init_once);
1200         if (ext4_inode_cachep == NULL)
1201                 return -ENOMEM;
1202         return 0;
1203 }
1204
1205 static void destroy_inodecache(void)
1206 {
1207         /*
1208          * Make sure all delayed rcu free inodes are flushed before we
1209          * destroy cache.
1210          */
1211         rcu_barrier();
1212         kmem_cache_destroy(ext4_inode_cachep);
1213 }
1214
1215 void ext4_clear_inode(struct inode *inode)
1216 {
1217         invalidate_inode_buffers(inode);
1218         clear_inode(inode);
1219         ext4_discard_preallocations(inode);
1220         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1221         dquot_drop(inode);
1222         if (EXT4_I(inode)->jinode) {
1223                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1224                                                EXT4_I(inode)->jinode);
1225                 jbd2_free_inode(EXT4_I(inode)->jinode);
1226                 EXT4_I(inode)->jinode = NULL;
1227         }
1228         fscrypt_put_encryption_info(inode);
1229         fsverity_cleanup_inode(inode);
1230 }
1231
1232 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1233                                         u64 ino, u32 generation)
1234 {
1235         struct inode *inode;
1236
1237         /*
1238          * Currently we don't know the generation for parent directory, so
1239          * a generation of 0 means "accept any"
1240          */
1241         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1242         if (IS_ERR(inode))
1243                 return ERR_CAST(inode);
1244         if (generation && inode->i_generation != generation) {
1245                 iput(inode);
1246                 return ERR_PTR(-ESTALE);
1247         }
1248
1249         return inode;
1250 }
1251
1252 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1253                                         int fh_len, int fh_type)
1254 {
1255         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1256                                     ext4_nfs_get_inode);
1257 }
1258
1259 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1260                                         int fh_len, int fh_type)
1261 {
1262         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1263                                     ext4_nfs_get_inode);
1264 }
1265
1266 static int ext4_nfs_commit_metadata(struct inode *inode)
1267 {
1268         struct writeback_control wbc = {
1269                 .sync_mode = WB_SYNC_ALL
1270         };
1271
1272         trace_ext4_nfs_commit_metadata(inode);
1273         return ext4_write_inode(inode, &wbc);
1274 }
1275
1276 /*
1277  * Try to release metadata pages (indirect blocks, directories) which are
1278  * mapped via the block device.  Since these pages could have journal heads
1279  * which would prevent try_to_free_buffers() from freeing them, we must use
1280  * jbd2 layer's try_to_free_buffers() function to release them.
1281  */
1282 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1283                                  gfp_t wait)
1284 {
1285         journal_t *journal = EXT4_SB(sb)->s_journal;
1286
1287         WARN_ON(PageChecked(page));
1288         if (!page_has_buffers(page))
1289                 return 0;
1290         if (journal)
1291                 return jbd2_journal_try_to_free_buffers(journal, page);
1292
1293         return try_to_free_buffers(page);
1294 }
1295
1296 #ifdef CONFIG_FS_ENCRYPTION
1297 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1298 {
1299         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1300                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1301 }
1302
1303 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1304                                                         void *fs_data)
1305 {
1306         handle_t *handle = fs_data;
1307         int res, res2, credits, retries = 0;
1308
1309         /*
1310          * Encrypting the root directory is not allowed because e2fsck expects
1311          * lost+found to exist and be unencrypted, and encrypting the root
1312          * directory would imply encrypting the lost+found directory as well as
1313          * the filename "lost+found" itself.
1314          */
1315         if (inode->i_ino == EXT4_ROOT_INO)
1316                 return -EPERM;
1317
1318         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1319                 return -EINVAL;
1320
1321         if (ext4_test_inode_flag(inode, EXT4_INODE_DAX))
1322                 return -EOPNOTSUPP;
1323
1324         res = ext4_convert_inline_data(inode);
1325         if (res)
1326                 return res;
1327
1328         /*
1329          * If a journal handle was specified, then the encryption context is
1330          * being set on a new inode via inheritance and is part of a larger
1331          * transaction to create the inode.  Otherwise the encryption context is
1332          * being set on an existing inode in its own transaction.  Only in the
1333          * latter case should the "retry on ENOSPC" logic be used.
1334          */
1335
1336         if (handle) {
1337                 res = ext4_xattr_set_handle(handle, inode,
1338                                             EXT4_XATTR_INDEX_ENCRYPTION,
1339                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1340                                             ctx, len, 0);
1341                 if (!res) {
1342                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1343                         ext4_clear_inode_state(inode,
1344                                         EXT4_STATE_MAY_INLINE_DATA);
1345                         /*
1346                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1347                          * S_DAX may be disabled
1348                          */
1349                         ext4_set_inode_flags(inode, false);
1350                 }
1351                 return res;
1352         }
1353
1354         res = dquot_initialize(inode);
1355         if (res)
1356                 return res;
1357 retry:
1358         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1359                                      &credits);
1360         if (res)
1361                 return res;
1362
1363         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1364         if (IS_ERR(handle))
1365                 return PTR_ERR(handle);
1366
1367         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1368                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1369                                     ctx, len, 0);
1370         if (!res) {
1371                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1372                 /*
1373                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1374                  * S_DAX may be disabled
1375                  */
1376                 ext4_set_inode_flags(inode, false);
1377                 res = ext4_mark_inode_dirty(handle, inode);
1378                 if (res)
1379                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1380         }
1381         res2 = ext4_journal_stop(handle);
1382
1383         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1384                 goto retry;
1385         if (!res)
1386                 res = res2;
1387         return res;
1388 }
1389
1390 static const union fscrypt_context *
1391 ext4_get_dummy_context(struct super_block *sb)
1392 {
1393         return EXT4_SB(sb)->s_dummy_enc_ctx.ctx;
1394 }
1395
1396 static bool ext4_has_stable_inodes(struct super_block *sb)
1397 {
1398         return ext4_has_feature_stable_inodes(sb);
1399 }
1400
1401 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1402                                        int *ino_bits_ret, int *lblk_bits_ret)
1403 {
1404         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1405         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1406 }
1407
1408 static const struct fscrypt_operations ext4_cryptops = {
1409         .key_prefix             = "ext4:",
1410         .get_context            = ext4_get_context,
1411         .set_context            = ext4_set_context,
1412         .get_dummy_context      = ext4_get_dummy_context,
1413         .empty_dir              = ext4_empty_dir,
1414         .max_namelen            = EXT4_NAME_LEN,
1415         .has_stable_inodes      = ext4_has_stable_inodes,
1416         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1417 };
1418 #endif
1419
1420 #ifdef CONFIG_QUOTA
1421 static const char * const quotatypes[] = INITQFNAMES;
1422 #define QTYPE2NAME(t) (quotatypes[t])
1423
1424 static int ext4_write_dquot(struct dquot *dquot);
1425 static int ext4_acquire_dquot(struct dquot *dquot);
1426 static int ext4_release_dquot(struct dquot *dquot);
1427 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1428 static int ext4_write_info(struct super_block *sb, int type);
1429 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1430                          const struct path *path);
1431 static int ext4_quota_on_mount(struct super_block *sb, int type);
1432 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1433                                size_t len, loff_t off);
1434 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1435                                 const char *data, size_t len, loff_t off);
1436 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1437                              unsigned int flags);
1438 static int ext4_enable_quotas(struct super_block *sb);
1439
1440 static struct dquot **ext4_get_dquots(struct inode *inode)
1441 {
1442         return EXT4_I(inode)->i_dquot;
1443 }
1444
1445 static const struct dquot_operations ext4_quota_operations = {
1446         .get_reserved_space     = ext4_get_reserved_space,
1447         .write_dquot            = ext4_write_dquot,
1448         .acquire_dquot          = ext4_acquire_dquot,
1449         .release_dquot          = ext4_release_dquot,
1450         .mark_dirty             = ext4_mark_dquot_dirty,
1451         .write_info             = ext4_write_info,
1452         .alloc_dquot            = dquot_alloc,
1453         .destroy_dquot          = dquot_destroy,
1454         .get_projid             = ext4_get_projid,
1455         .get_inode_usage        = ext4_get_inode_usage,
1456         .get_next_id            = dquot_get_next_id,
1457 };
1458
1459 static const struct quotactl_ops ext4_qctl_operations = {
1460         .quota_on       = ext4_quota_on,
1461         .quota_off      = ext4_quota_off,
1462         .quota_sync     = dquot_quota_sync,
1463         .get_state      = dquot_get_state,
1464         .set_info       = dquot_set_dqinfo,
1465         .get_dqblk      = dquot_get_dqblk,
1466         .set_dqblk      = dquot_set_dqblk,
1467         .get_nextdqblk  = dquot_get_next_dqblk,
1468 };
1469 #endif
1470
1471 static const struct super_operations ext4_sops = {
1472         .alloc_inode    = ext4_alloc_inode,
1473         .free_inode     = ext4_free_in_core_inode,
1474         .destroy_inode  = ext4_destroy_inode,
1475         .write_inode    = ext4_write_inode,
1476         .dirty_inode    = ext4_dirty_inode,
1477         .drop_inode     = ext4_drop_inode,
1478         .evict_inode    = ext4_evict_inode,
1479         .put_super      = ext4_put_super,
1480         .sync_fs        = ext4_sync_fs,
1481         .freeze_fs      = ext4_freeze,
1482         .unfreeze_fs    = ext4_unfreeze,
1483         .statfs         = ext4_statfs,
1484         .remount_fs     = ext4_remount,
1485         .show_options   = ext4_show_options,
1486 #ifdef CONFIG_QUOTA
1487         .quota_read     = ext4_quota_read,
1488         .quota_write    = ext4_quota_write,
1489         .get_dquots     = ext4_get_dquots,
1490 #endif
1491         .bdev_try_to_free_page = bdev_try_to_free_page,
1492 };
1493
1494 static const struct export_operations ext4_export_ops = {
1495         .fh_to_dentry = ext4_fh_to_dentry,
1496         .fh_to_parent = ext4_fh_to_parent,
1497         .get_parent = ext4_get_parent,
1498         .commit_metadata = ext4_nfs_commit_metadata,
1499 };
1500
1501 enum {
1502         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1503         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1504         Opt_nouid32, Opt_debug, Opt_removed,
1505         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1506         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1507         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1508         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1509         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1510         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1511         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1512         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1513         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1514         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
1515         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1516         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1517         Opt_nowarn_on_error, Opt_mblk_io_submit,
1518         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1519         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1520         Opt_inode_readahead_blks, Opt_journal_ioprio,
1521         Opt_dioread_nolock, Opt_dioread_lock,
1522         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1523         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1524         Opt_prefetch_block_bitmaps,
1525 };
1526
1527 static const match_table_t tokens = {
1528         {Opt_bsd_df, "bsddf"},
1529         {Opt_minix_df, "minixdf"},
1530         {Opt_grpid, "grpid"},
1531         {Opt_grpid, "bsdgroups"},
1532         {Opt_nogrpid, "nogrpid"},
1533         {Opt_nogrpid, "sysvgroups"},
1534         {Opt_resgid, "resgid=%u"},
1535         {Opt_resuid, "resuid=%u"},
1536         {Opt_sb, "sb=%u"},
1537         {Opt_err_cont, "errors=continue"},
1538         {Opt_err_panic, "errors=panic"},
1539         {Opt_err_ro, "errors=remount-ro"},
1540         {Opt_nouid32, "nouid32"},
1541         {Opt_debug, "debug"},
1542         {Opt_removed, "oldalloc"},
1543         {Opt_removed, "orlov"},
1544         {Opt_user_xattr, "user_xattr"},
1545         {Opt_nouser_xattr, "nouser_xattr"},
1546         {Opt_acl, "acl"},
1547         {Opt_noacl, "noacl"},
1548         {Opt_noload, "norecovery"},
1549         {Opt_noload, "noload"},
1550         {Opt_removed, "nobh"},
1551         {Opt_removed, "bh"},
1552         {Opt_commit, "commit=%u"},
1553         {Opt_min_batch_time, "min_batch_time=%u"},
1554         {Opt_max_batch_time, "max_batch_time=%u"},
1555         {Opt_journal_dev, "journal_dev=%u"},
1556         {Opt_journal_path, "journal_path=%s"},
1557         {Opt_journal_checksum, "journal_checksum"},
1558         {Opt_nojournal_checksum, "nojournal_checksum"},
1559         {Opt_journal_async_commit, "journal_async_commit"},
1560         {Opt_abort, "abort"},
1561         {Opt_data_journal, "data=journal"},
1562         {Opt_data_ordered, "data=ordered"},
1563         {Opt_data_writeback, "data=writeback"},
1564         {Opt_data_err_abort, "data_err=abort"},
1565         {Opt_data_err_ignore, "data_err=ignore"},
1566         {Opt_offusrjquota, "usrjquota="},
1567         {Opt_usrjquota, "usrjquota=%s"},
1568         {Opt_offgrpjquota, "grpjquota="},
1569         {Opt_grpjquota, "grpjquota=%s"},
1570         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1571         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1572         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1573         {Opt_grpquota, "grpquota"},
1574         {Opt_noquota, "noquota"},
1575         {Opt_quota, "quota"},
1576         {Opt_usrquota, "usrquota"},
1577         {Opt_prjquota, "prjquota"},
1578         {Opt_barrier, "barrier=%u"},
1579         {Opt_barrier, "barrier"},
1580         {Opt_nobarrier, "nobarrier"},
1581         {Opt_i_version, "i_version"},
1582         {Opt_dax, "dax"},
1583         {Opt_dax_always, "dax=always"},
1584         {Opt_dax_inode, "dax=inode"},
1585         {Opt_dax_never, "dax=never"},
1586         {Opt_stripe, "stripe=%u"},
1587         {Opt_delalloc, "delalloc"},
1588         {Opt_warn_on_error, "warn_on_error"},
1589         {Opt_nowarn_on_error, "nowarn_on_error"},
1590         {Opt_lazytime, "lazytime"},
1591         {Opt_nolazytime, "nolazytime"},
1592         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1593         {Opt_nodelalloc, "nodelalloc"},
1594         {Opt_removed, "mblk_io_submit"},
1595         {Opt_removed, "nomblk_io_submit"},
1596         {Opt_block_validity, "block_validity"},
1597         {Opt_noblock_validity, "noblock_validity"},
1598         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1599         {Opt_journal_ioprio, "journal_ioprio=%u"},
1600         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1601         {Opt_auto_da_alloc, "auto_da_alloc"},
1602         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1603         {Opt_dioread_nolock, "dioread_nolock"},
1604         {Opt_dioread_lock, "nodioread_nolock"},
1605         {Opt_dioread_lock, "dioread_lock"},
1606         {Opt_discard, "discard"},
1607         {Opt_nodiscard, "nodiscard"},
1608         {Opt_init_itable, "init_itable=%u"},
1609         {Opt_init_itable, "init_itable"},
1610         {Opt_noinit_itable, "noinit_itable"},
1611         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1612         {Opt_test_dummy_encryption, "test_dummy_encryption=%s"},
1613         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1614         {Opt_nombcache, "nombcache"},
1615         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1616         {Opt_prefetch_block_bitmaps, "prefetch_block_bitmaps"},
1617         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1618         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1619         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1620         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1621         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1622         {Opt_err, NULL},
1623 };
1624
1625 static ext4_fsblk_t get_sb_block(void **data)
1626 {
1627         ext4_fsblk_t    sb_block;
1628         char            *options = (char *) *data;
1629
1630         if (!options || strncmp(options, "sb=", 3) != 0)
1631                 return 1;       /* Default location */
1632
1633         options += 3;
1634         /* TODO: use simple_strtoll with >32bit ext4 */
1635         sb_block = simple_strtoul(options, &options, 0);
1636         if (*options && *options != ',') {
1637                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1638                        (char *) *data);
1639                 return 1;
1640         }
1641         if (*options == ',')
1642                 options++;
1643         *data = (void *) options;
1644
1645         return sb_block;
1646 }
1647
1648 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1649 static const char deprecated_msg[] =
1650         "Mount option \"%s\" will be removed by %s\n"
1651         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1652
1653 #ifdef CONFIG_QUOTA
1654 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1655 {
1656         struct ext4_sb_info *sbi = EXT4_SB(sb);
1657         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1658         int ret = -1;
1659
1660         if (sb_any_quota_loaded(sb) && !old_qname) {
1661                 ext4_msg(sb, KERN_ERR,
1662                         "Cannot change journaled "
1663                         "quota options when quota turned on");
1664                 return -1;
1665         }
1666         if (ext4_has_feature_quota(sb)) {
1667                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1668                          "ignored when QUOTA feature is enabled");
1669                 return 1;
1670         }
1671         qname = match_strdup(args);
1672         if (!qname) {
1673                 ext4_msg(sb, KERN_ERR,
1674                         "Not enough memory for storing quotafile name");
1675                 return -1;
1676         }
1677         if (old_qname) {
1678                 if (strcmp(old_qname, qname) == 0)
1679                         ret = 1;
1680                 else
1681                         ext4_msg(sb, KERN_ERR,
1682                                  "%s quota file already specified",
1683                                  QTYPE2NAME(qtype));
1684                 goto errout;
1685         }
1686         if (strchr(qname, '/')) {
1687                 ext4_msg(sb, KERN_ERR,
1688                         "quotafile must be on filesystem root");
1689                 goto errout;
1690         }
1691         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1692         set_opt(sb, QUOTA);
1693         return 1;
1694 errout:
1695         kfree(qname);
1696         return ret;
1697 }
1698
1699 static int clear_qf_name(struct super_block *sb, int qtype)
1700 {
1701
1702         struct ext4_sb_info *sbi = EXT4_SB(sb);
1703         char *old_qname = get_qf_name(sb, sbi, qtype);
1704
1705         if (sb_any_quota_loaded(sb) && old_qname) {
1706                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1707                         " when quota turned on");
1708                 return -1;
1709         }
1710         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1711         synchronize_rcu();
1712         kfree(old_qname);
1713         return 1;
1714 }
1715 #endif
1716
1717 #define MOPT_SET        0x0001
1718 #define MOPT_CLEAR      0x0002
1719 #define MOPT_NOSUPPORT  0x0004
1720 #define MOPT_EXPLICIT   0x0008
1721 #define MOPT_CLEAR_ERR  0x0010
1722 #define MOPT_GTE0       0x0020
1723 #ifdef CONFIG_QUOTA
1724 #define MOPT_Q          0
1725 #define MOPT_QFMT       0x0040
1726 #else
1727 #define MOPT_Q          MOPT_NOSUPPORT
1728 #define MOPT_QFMT       MOPT_NOSUPPORT
1729 #endif
1730 #define MOPT_DATAJ      0x0080
1731 #define MOPT_NO_EXT2    0x0100
1732 #define MOPT_NO_EXT3    0x0200
1733 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1734 #define MOPT_STRING     0x0400
1735 #define MOPT_SKIP       0x0800
1736
1737 static const struct mount_opts {
1738         int     token;
1739         int     mount_opt;
1740         int     flags;
1741 } ext4_mount_opts[] = {
1742         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1743         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1744         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1745         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1746         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1747         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1748         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1749          MOPT_EXT4_ONLY | MOPT_SET},
1750         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1751          MOPT_EXT4_ONLY | MOPT_CLEAR},
1752         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1753         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1754         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1755          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1756         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1757          MOPT_EXT4_ONLY | MOPT_CLEAR},
1758         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1759         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1760         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1761          MOPT_EXT4_ONLY | MOPT_CLEAR},
1762         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1763          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1764         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1765                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1766          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1767         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1768         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1769         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1770         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1771         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1772          MOPT_NO_EXT2},
1773         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1774          MOPT_NO_EXT2},
1775         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1776         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1777         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1778         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1779         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1780         {Opt_commit, 0, MOPT_GTE0},
1781         {Opt_max_batch_time, 0, MOPT_GTE0},
1782         {Opt_min_batch_time, 0, MOPT_GTE0},
1783         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1784         {Opt_init_itable, 0, MOPT_GTE0},
1785         {Opt_dax, EXT4_MOUNT_DAX_ALWAYS, MOPT_SET | MOPT_SKIP},
1786         {Opt_dax_always, EXT4_MOUNT_DAX_ALWAYS,
1787                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1788         {Opt_dax_inode, EXT4_MOUNT2_DAX_INODE,
1789                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1790         {Opt_dax_never, EXT4_MOUNT2_DAX_NEVER,
1791                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1792         {Opt_stripe, 0, MOPT_GTE0},
1793         {Opt_resuid, 0, MOPT_GTE0},
1794         {Opt_resgid, 0, MOPT_GTE0},
1795         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1796         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1797         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1798         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1799         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1800         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1801          MOPT_NO_EXT2 | MOPT_DATAJ},
1802         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1803         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1804 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1805         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1806         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1807 #else
1808         {Opt_acl, 0, MOPT_NOSUPPORT},
1809         {Opt_noacl, 0, MOPT_NOSUPPORT},
1810 #endif
1811         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1812         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1813         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1814         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1815         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1816                                                         MOPT_SET | MOPT_Q},
1817         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1818                                                         MOPT_SET | MOPT_Q},
1819         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1820                                                         MOPT_SET | MOPT_Q},
1821         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1822                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1823                                                         MOPT_CLEAR | MOPT_Q},
1824         {Opt_usrjquota, 0, MOPT_Q},
1825         {Opt_grpjquota, 0, MOPT_Q},
1826         {Opt_offusrjquota, 0, MOPT_Q},
1827         {Opt_offgrpjquota, 0, MOPT_Q},
1828         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1829         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1830         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1831         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1832         {Opt_test_dummy_encryption, 0, MOPT_STRING},
1833         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1834         {Opt_prefetch_block_bitmaps, EXT4_MOUNT_PREFETCH_BLOCK_BITMAPS,
1835          MOPT_SET},
1836         {Opt_err, 0, 0}
1837 };
1838
1839 #ifdef CONFIG_UNICODE
1840 static const struct ext4_sb_encodings {
1841         __u16 magic;
1842         char *name;
1843         char *version;
1844 } ext4_sb_encoding_map[] = {
1845         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
1846 };
1847
1848 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
1849                                  const struct ext4_sb_encodings **encoding,
1850                                  __u16 *flags)
1851 {
1852         __u16 magic = le16_to_cpu(es->s_encoding);
1853         int i;
1854
1855         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1856                 if (magic == ext4_sb_encoding_map[i].magic)
1857                         break;
1858
1859         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
1860                 return -EINVAL;
1861
1862         *encoding = &ext4_sb_encoding_map[i];
1863         *flags = le16_to_cpu(es->s_encoding_flags);
1864
1865         return 0;
1866 }
1867 #endif
1868
1869 static int ext4_set_test_dummy_encryption(struct super_block *sb,
1870                                           const char *opt,
1871                                           const substring_t *arg,
1872                                           bool is_remount)
1873 {
1874 #ifdef CONFIG_FS_ENCRYPTION
1875         struct ext4_sb_info *sbi = EXT4_SB(sb);
1876         int err;
1877
1878         /*
1879          * This mount option is just for testing, and it's not worthwhile to
1880          * implement the extra complexity (e.g. RCU protection) that would be
1881          * needed to allow it to be set or changed during remount.  We do allow
1882          * it to be specified during remount, but only if there is no change.
1883          */
1884         if (is_remount && !sbi->s_dummy_enc_ctx.ctx) {
1885                 ext4_msg(sb, KERN_WARNING,
1886                          "Can't set test_dummy_encryption on remount");
1887                 return -1;
1888         }
1889         err = fscrypt_set_test_dummy_encryption(sb, arg, &sbi->s_dummy_enc_ctx);
1890         if (err) {
1891                 if (err == -EEXIST)
1892                         ext4_msg(sb, KERN_WARNING,
1893                                  "Can't change test_dummy_encryption on remount");
1894                 else if (err == -EINVAL)
1895                         ext4_msg(sb, KERN_WARNING,
1896                                  "Value of option \"%s\" is unrecognized", opt);
1897                 else
1898                         ext4_msg(sb, KERN_WARNING,
1899                                  "Error processing option \"%s\" [%d]",
1900                                  opt, err);
1901                 return -1;
1902         }
1903         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
1904 #else
1905         ext4_msg(sb, KERN_WARNING,
1906                  "Test dummy encryption mount option ignored");
1907 #endif
1908         return 1;
1909 }
1910
1911 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1912                             substring_t *args, unsigned long *journal_devnum,
1913                             unsigned int *journal_ioprio, int is_remount)
1914 {
1915         struct ext4_sb_info *sbi = EXT4_SB(sb);
1916         const struct mount_opts *m;
1917         kuid_t uid;
1918         kgid_t gid;
1919         int arg = 0;
1920
1921 #ifdef CONFIG_QUOTA
1922         if (token == Opt_usrjquota)
1923                 return set_qf_name(sb, USRQUOTA, &args[0]);
1924         else if (token == Opt_grpjquota)
1925                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1926         else if (token == Opt_offusrjquota)
1927                 return clear_qf_name(sb, USRQUOTA);
1928         else if (token == Opt_offgrpjquota)
1929                 return clear_qf_name(sb, GRPQUOTA);
1930 #endif
1931         switch (token) {
1932         case Opt_noacl:
1933         case Opt_nouser_xattr:
1934                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1935                 break;
1936         case Opt_sb:
1937                 return 1;       /* handled by get_sb_block() */
1938         case Opt_removed:
1939                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1940                 return 1;
1941         case Opt_abort:
1942                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1943                 return 1;
1944         case Opt_i_version:
1945                 sb->s_flags |= SB_I_VERSION;
1946                 return 1;
1947         case Opt_lazytime:
1948                 sb->s_flags |= SB_LAZYTIME;
1949                 return 1;
1950         case Opt_nolazytime:
1951                 sb->s_flags &= ~SB_LAZYTIME;
1952                 return 1;
1953         }
1954
1955         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1956                 if (token == m->token)
1957                         break;
1958
1959         if (m->token == Opt_err) {
1960                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1961                          "or missing value", opt);
1962                 return -1;
1963         }
1964
1965         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1966                 ext4_msg(sb, KERN_ERR,
1967                          "Mount option \"%s\" incompatible with ext2", opt);
1968                 return -1;
1969         }
1970         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1971                 ext4_msg(sb, KERN_ERR,
1972                          "Mount option \"%s\" incompatible with ext3", opt);
1973                 return -1;
1974         }
1975
1976         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1977                 return -1;
1978         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1979                 return -1;
1980         if (m->flags & MOPT_EXPLICIT) {
1981                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1982                         set_opt2(sb, EXPLICIT_DELALLOC);
1983                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1984                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1985                 } else
1986                         return -1;
1987         }
1988         if (m->flags & MOPT_CLEAR_ERR)
1989                 clear_opt(sb, ERRORS_MASK);
1990         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1991                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1992                          "options when quota turned on");
1993                 return -1;
1994         }
1995
1996         if (m->flags & MOPT_NOSUPPORT) {
1997                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1998         } else if (token == Opt_commit) {
1999                 if (arg == 0)
2000                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
2001                 else if (arg > INT_MAX / HZ) {
2002                         ext4_msg(sb, KERN_ERR,
2003                                  "Invalid commit interval %d, "
2004                                  "must be smaller than %d",
2005                                  arg, INT_MAX / HZ);
2006                         return -1;
2007                 }
2008                 sbi->s_commit_interval = HZ * arg;
2009         } else if (token == Opt_debug_want_extra_isize) {
2010                 if ((arg & 1) ||
2011                     (arg < 4) ||
2012                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
2013                         ext4_msg(sb, KERN_ERR,
2014                                  "Invalid want_extra_isize %d", arg);
2015                         return -1;
2016                 }
2017                 sbi->s_want_extra_isize = arg;
2018         } else if (token == Opt_max_batch_time) {
2019                 sbi->s_max_batch_time = arg;
2020         } else if (token == Opt_min_batch_time) {
2021                 sbi->s_min_batch_time = arg;
2022         } else if (token == Opt_inode_readahead_blks) {
2023                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
2024                         ext4_msg(sb, KERN_ERR,
2025                                  "EXT4-fs: inode_readahead_blks must be "
2026                                  "0 or a power of 2 smaller than 2^31");
2027                         return -1;
2028                 }
2029                 sbi->s_inode_readahead_blks = arg;
2030         } else if (token == Opt_init_itable) {
2031                 set_opt(sb, INIT_INODE_TABLE);
2032                 if (!args->from)
2033                         arg = EXT4_DEF_LI_WAIT_MULT;
2034                 sbi->s_li_wait_mult = arg;
2035         } else if (token == Opt_max_dir_size_kb) {
2036                 sbi->s_max_dir_size_kb = arg;
2037         } else if (token == Opt_stripe) {
2038                 sbi->s_stripe = arg;
2039         } else if (token == Opt_resuid) {
2040                 uid = make_kuid(current_user_ns(), arg);
2041                 if (!uid_valid(uid)) {
2042                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
2043                         return -1;
2044                 }
2045                 sbi->s_resuid = uid;
2046         } else if (token == Opt_resgid) {
2047                 gid = make_kgid(current_user_ns(), arg);
2048                 if (!gid_valid(gid)) {
2049                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
2050                         return -1;
2051                 }
2052                 sbi->s_resgid = gid;
2053         } else if (token == Opt_journal_dev) {
2054                 if (is_remount) {
2055                         ext4_msg(sb, KERN_ERR,
2056                                  "Cannot specify journal on remount");
2057                         return -1;
2058                 }
2059                 *journal_devnum = arg;
2060         } else if (token == Opt_journal_path) {
2061                 char *journal_path;
2062                 struct inode *journal_inode;
2063                 struct path path;
2064                 int error;
2065
2066                 if (is_remount) {
2067                         ext4_msg(sb, KERN_ERR,
2068                                  "Cannot specify journal on remount");
2069                         return -1;
2070                 }
2071                 journal_path = match_strdup(&args[0]);
2072                 if (!journal_path) {
2073                         ext4_msg(sb, KERN_ERR, "error: could not dup "
2074                                 "journal device string");
2075                         return -1;
2076                 }
2077
2078                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2079                 if (error) {
2080                         ext4_msg(sb, KERN_ERR, "error: could not find "
2081                                 "journal device path: error %d", error);
2082                         kfree(journal_path);
2083                         return -1;
2084                 }
2085
2086                 journal_inode = d_inode(path.dentry);
2087                 if (!S_ISBLK(journal_inode->i_mode)) {
2088                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
2089                                 "is not a block device", journal_path);
2090                         path_put(&path);
2091                         kfree(journal_path);
2092                         return -1;
2093                 }
2094
2095                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
2096                 path_put(&path);
2097                 kfree(journal_path);
2098         } else if (token == Opt_journal_ioprio) {
2099                 if (arg > 7) {
2100                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2101                                  " (must be 0-7)");
2102                         return -1;
2103                 }
2104                 *journal_ioprio =
2105                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2106         } else if (token == Opt_test_dummy_encryption) {
2107                 return ext4_set_test_dummy_encryption(sb, opt, &args[0],
2108                                                       is_remount);
2109         } else if (m->flags & MOPT_DATAJ) {
2110                 if (is_remount) {
2111                         if (!sbi->s_journal)
2112                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2113                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2114                                 ext4_msg(sb, KERN_ERR,
2115                                          "Cannot change data mode on remount");
2116                                 return -1;
2117                         }
2118                 } else {
2119                         clear_opt(sb, DATA_FLAGS);
2120                         sbi->s_mount_opt |= m->mount_opt;
2121                 }
2122 #ifdef CONFIG_QUOTA
2123         } else if (m->flags & MOPT_QFMT) {
2124                 if (sb_any_quota_loaded(sb) &&
2125                     sbi->s_jquota_fmt != m->mount_opt) {
2126                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2127                                  "quota options when quota turned on");
2128                         return -1;
2129                 }
2130                 if (ext4_has_feature_quota(sb)) {
2131                         ext4_msg(sb, KERN_INFO,
2132                                  "Quota format mount options ignored "
2133                                  "when QUOTA feature is enabled");
2134                         return 1;
2135                 }
2136                 sbi->s_jquota_fmt = m->mount_opt;
2137 #endif
2138         } else if (token == Opt_dax || token == Opt_dax_always ||
2139                    token == Opt_dax_inode || token == Opt_dax_never) {
2140 #ifdef CONFIG_FS_DAX
2141                 switch (token) {
2142                 case Opt_dax:
2143                 case Opt_dax_always:
2144                         if (is_remount &&
2145                             (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2146                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2147                         fail_dax_change_remount:
2148                                 ext4_msg(sb, KERN_ERR, "can't change "
2149                                          "dax mount option while remounting");
2150                                 return -1;
2151                         }
2152                         if (is_remount &&
2153                             (test_opt(sb, DATA_FLAGS) ==
2154                              EXT4_MOUNT_JOURNAL_DATA)) {
2155                                     ext4_msg(sb, KERN_ERR, "can't mount with "
2156                                              "both data=journal and dax");
2157                                     return -1;
2158                         }
2159                         ext4_msg(sb, KERN_WARNING,
2160                                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2161                         sbi->s_mount_opt |= EXT4_MOUNT_DAX_ALWAYS;
2162                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2163                         break;
2164                 case Opt_dax_never:
2165                         if (is_remount &&
2166                             (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2167                              (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS)))
2168                                 goto fail_dax_change_remount;
2169                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2170                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2171                         break;
2172                 case Opt_dax_inode:
2173                         if (is_remount &&
2174                             ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2175                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2176                              !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE)))
2177                                 goto fail_dax_change_remount;
2178                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2179                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2180                         /* Strictly for printing options */
2181                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_INODE;
2182                         break;
2183                 }
2184 #else
2185                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2186                 sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2187                 sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2188                 return -1;
2189 #endif
2190         } else if (token == Opt_data_err_abort) {
2191                 sbi->s_mount_opt |= m->mount_opt;
2192         } else if (token == Opt_data_err_ignore) {
2193                 sbi->s_mount_opt &= ~m->mount_opt;
2194         } else {
2195                 if (!args->from)
2196                         arg = 1;
2197                 if (m->flags & MOPT_CLEAR)
2198                         arg = !arg;
2199                 else if (unlikely(!(m->flags & MOPT_SET))) {
2200                         ext4_msg(sb, KERN_WARNING,
2201                                  "buggy handling of option %s", opt);
2202                         WARN_ON(1);
2203                         return -1;
2204                 }
2205                 if (arg != 0)
2206                         sbi->s_mount_opt |= m->mount_opt;
2207                 else
2208                         sbi->s_mount_opt &= ~m->mount_opt;
2209         }
2210         return 1;
2211 }
2212
2213 static int parse_options(char *options, struct super_block *sb,
2214                          unsigned long *journal_devnum,
2215                          unsigned int *journal_ioprio,
2216                          int is_remount)
2217 {
2218         struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2219         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2220         substring_t args[MAX_OPT_ARGS];
2221         int token;
2222
2223         if (!options)
2224                 return 1;
2225
2226         while ((p = strsep(&options, ",")) != NULL) {
2227                 if (!*p)
2228                         continue;
2229                 /*
2230                  * Initialize args struct so we know whether arg was
2231                  * found; some options take optional arguments.
2232                  */
2233                 args[0].to = args[0].from = NULL;
2234                 token = match_token(p, tokens, args);
2235                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2236                                      journal_ioprio, is_remount) < 0)
2237                         return 0;
2238         }
2239 #ifdef CONFIG_QUOTA
2240         /*
2241          * We do the test below only for project quotas. 'usrquota' and
2242          * 'grpquota' mount options are allowed even without quota feature
2243          * to support legacy quotas in quota files.
2244          */
2245         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2246                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2247                          "Cannot enable project quota enforcement.");
2248                 return 0;
2249         }
2250         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2251         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2252         if (usr_qf_name || grp_qf_name) {
2253                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2254                         clear_opt(sb, USRQUOTA);
2255
2256                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2257                         clear_opt(sb, GRPQUOTA);
2258
2259                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2260                         ext4_msg(sb, KERN_ERR, "old and new quota "
2261                                         "format mixing");
2262                         return 0;
2263                 }
2264
2265                 if (!sbi->s_jquota_fmt) {
2266                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2267                                         "not specified");
2268                         return 0;
2269                 }
2270         }
2271 #endif
2272         if (test_opt(sb, DIOREAD_NOLOCK)) {
2273                 int blocksize =
2274                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2275                 if (blocksize < PAGE_SIZE)
2276                         ext4_msg(sb, KERN_WARNING, "Warning: mounting with an "
2277                                  "experimental mount option 'dioread_nolock' "
2278                                  "for blocksize < PAGE_SIZE");
2279         }
2280         return 1;
2281 }
2282
2283 static inline void ext4_show_quota_options(struct seq_file *seq,
2284                                            struct super_block *sb)
2285 {
2286 #if defined(CONFIG_QUOTA)
2287         struct ext4_sb_info *sbi = EXT4_SB(sb);
2288         char *usr_qf_name, *grp_qf_name;
2289
2290         if (sbi->s_jquota_fmt) {
2291                 char *fmtname = "";
2292
2293                 switch (sbi->s_jquota_fmt) {
2294                 case QFMT_VFS_OLD:
2295                         fmtname = "vfsold";
2296                         break;
2297                 case QFMT_VFS_V0:
2298                         fmtname = "vfsv0";
2299                         break;
2300                 case QFMT_VFS_V1:
2301                         fmtname = "vfsv1";
2302                         break;
2303                 }
2304                 seq_printf(seq, ",jqfmt=%s", fmtname);
2305         }
2306
2307         rcu_read_lock();
2308         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2309         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2310         if (usr_qf_name)
2311                 seq_show_option(seq, "usrjquota", usr_qf_name);
2312         if (grp_qf_name)
2313                 seq_show_option(seq, "grpjquota", grp_qf_name);
2314         rcu_read_unlock();
2315 #endif
2316 }
2317
2318 static const char *token2str(int token)
2319 {
2320         const struct match_token *t;
2321
2322         for (t = tokens; t->token != Opt_err; t++)
2323                 if (t->token == token && !strchr(t->pattern, '='))
2324                         break;
2325         return t->pattern;
2326 }
2327
2328 /*
2329  * Show an option if
2330  *  - it's set to a non-default value OR
2331  *  - if the per-sb default is different from the global default
2332  */
2333 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2334                               int nodefs)
2335 {
2336         struct ext4_sb_info *sbi = EXT4_SB(sb);
2337         struct ext4_super_block *es = sbi->s_es;
2338         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2339         const struct mount_opts *m;
2340         char sep = nodefs ? '\n' : ',';
2341
2342 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2343 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2344
2345         if (sbi->s_sb_block != 1)
2346                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2347
2348         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2349                 int want_set = m->flags & MOPT_SET;
2350                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2351                     (m->flags & MOPT_CLEAR_ERR) || m->flags & MOPT_SKIP)
2352                         continue;
2353                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2354                         continue; /* skip if same as the default */
2355                 if ((want_set &&
2356                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2357                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2358                         continue; /* select Opt_noFoo vs Opt_Foo */
2359                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2360         }
2361
2362         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2363             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2364                 SEQ_OPTS_PRINT("resuid=%u",
2365                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2366         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2367             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2368                 SEQ_OPTS_PRINT("resgid=%u",
2369                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2370         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2371         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2372                 SEQ_OPTS_PUTS("errors=remount-ro");
2373         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2374                 SEQ_OPTS_PUTS("errors=continue");
2375         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2376                 SEQ_OPTS_PUTS("errors=panic");
2377         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2378                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2379         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2380                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2381         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2382                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2383         if (sb->s_flags & SB_I_VERSION)
2384                 SEQ_OPTS_PUTS("i_version");
2385         if (nodefs || sbi->s_stripe)
2386                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2387         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2388                         (sbi->s_mount_opt ^ def_mount_opt)) {
2389                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2390                         SEQ_OPTS_PUTS("data=journal");
2391                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2392                         SEQ_OPTS_PUTS("data=ordered");
2393                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2394                         SEQ_OPTS_PUTS("data=writeback");
2395         }
2396         if (nodefs ||
2397             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2398                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2399                                sbi->s_inode_readahead_blks);
2400
2401         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2402                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2403                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2404         if (nodefs || sbi->s_max_dir_size_kb)
2405                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2406         if (test_opt(sb, DATA_ERR_ABORT))
2407                 SEQ_OPTS_PUTS("data_err=abort");
2408
2409         fscrypt_show_test_dummy_encryption(seq, sep, sb);
2410
2411         if (test_opt(sb, DAX_ALWAYS)) {
2412                 if (IS_EXT2_SB(sb))
2413                         SEQ_OPTS_PUTS("dax");
2414                 else
2415                         SEQ_OPTS_PUTS("dax=always");
2416         } else if (test_opt2(sb, DAX_NEVER)) {
2417                 SEQ_OPTS_PUTS("dax=never");
2418         } else if (test_opt2(sb, DAX_INODE)) {
2419                 SEQ_OPTS_PUTS("dax=inode");
2420         }
2421
2422         ext4_show_quota_options(seq, sb);
2423         return 0;
2424 }
2425
2426 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2427 {
2428         return _ext4_show_options(seq, root->d_sb, 0);
2429 }
2430
2431 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2432 {
2433         struct super_block *sb = seq->private;
2434         int rc;
2435
2436         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2437         rc = _ext4_show_options(seq, sb, 1);
2438         seq_puts(seq, "\n");
2439         return rc;
2440 }
2441
2442 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2443                             int read_only)
2444 {
2445         struct ext4_sb_info *sbi = EXT4_SB(sb);
2446         int err = 0;
2447
2448         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2449                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2450                          "forcing read-only mode");
2451                 err = -EROFS;
2452                 goto done;
2453         }
2454         if (read_only)
2455                 goto done;
2456         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2457                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2458                          "running e2fsck is recommended");
2459         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2460                 ext4_msg(sb, KERN_WARNING,
2461                          "warning: mounting fs with errors, "
2462                          "running e2fsck is recommended");
2463         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2464                  le16_to_cpu(es->s_mnt_count) >=
2465                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2466                 ext4_msg(sb, KERN_WARNING,
2467                          "warning: maximal mount count reached, "
2468                          "running e2fsck is recommended");
2469         else if (le32_to_cpu(es->s_checkinterval) &&
2470                  (ext4_get_tstamp(es, s_lastcheck) +
2471                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2472                 ext4_msg(sb, KERN_WARNING,
2473                          "warning: checktime reached, "
2474                          "running e2fsck is recommended");
2475         if (!sbi->s_journal)
2476                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2477         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2478                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2479         le16_add_cpu(&es->s_mnt_count, 1);
2480         ext4_update_tstamp(es, s_mtime);
2481         if (sbi->s_journal)
2482                 ext4_set_feature_journal_needs_recovery(sb);
2483
2484         err = ext4_commit_super(sb, 1);
2485 done:
2486         if (test_opt(sb, DEBUG))
2487                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2488                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2489                         sb->s_blocksize,
2490                         sbi->s_groups_count,
2491                         EXT4_BLOCKS_PER_GROUP(sb),
2492                         EXT4_INODES_PER_GROUP(sb),
2493                         sbi->s_mount_opt, sbi->s_mount_opt2);
2494
2495         cleancache_init_fs(sb);
2496         return err;
2497 }
2498
2499 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2500 {
2501         struct ext4_sb_info *sbi = EXT4_SB(sb);
2502         struct flex_groups **old_groups, **new_groups;
2503         int size, i, j;
2504
2505         if (!sbi->s_log_groups_per_flex)
2506                 return 0;
2507
2508         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2509         if (size <= sbi->s_flex_groups_allocated)
2510                 return 0;
2511
2512         new_groups = kvzalloc(roundup_pow_of_two(size *
2513                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2514         if (!new_groups) {
2515                 ext4_msg(sb, KERN_ERR,
2516                          "not enough memory for %d flex group pointers", size);
2517                 return -ENOMEM;
2518         }
2519         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2520                 new_groups[i] = kvzalloc(roundup_pow_of_two(
2521                                          sizeof(struct flex_groups)),
2522                                          GFP_KERNEL);
2523                 if (!new_groups[i]) {
2524                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
2525                                 kvfree(new_groups[j]);
2526                         kvfree(new_groups);
2527                         ext4_msg(sb, KERN_ERR,
2528                                  "not enough memory for %d flex groups", size);
2529                         return -ENOMEM;
2530                 }
2531         }
2532         rcu_read_lock();
2533         old_groups = rcu_dereference(sbi->s_flex_groups);
2534         if (old_groups)
2535                 memcpy(new_groups, old_groups,
2536                        (sbi->s_flex_groups_allocated *
2537                         sizeof(struct flex_groups *)));
2538         rcu_read_unlock();
2539         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2540         sbi->s_flex_groups_allocated = size;
2541         if (old_groups)
2542                 ext4_kvfree_array_rcu(old_groups);
2543         return 0;
2544 }
2545
2546 static int ext4_fill_flex_info(struct super_block *sb)
2547 {
2548         struct ext4_sb_info *sbi = EXT4_SB(sb);
2549         struct ext4_group_desc *gdp = NULL;
2550         struct flex_groups *fg;
2551         ext4_group_t flex_group;
2552         int i, err;
2553
2554         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2555         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2556                 sbi->s_log_groups_per_flex = 0;
2557                 return 1;
2558         }
2559
2560         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2561         if (err)
2562                 goto failed;
2563
2564         for (i = 0; i < sbi->s_groups_count; i++) {
2565                 gdp = ext4_get_group_desc(sb, i, NULL);
2566
2567                 flex_group = ext4_flex_group(sbi, i);
2568                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2569                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2570                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2571                              &fg->free_clusters);
2572                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2573         }
2574
2575         return 1;
2576 failed:
2577         return 0;
2578 }
2579
2580 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2581                                    struct ext4_group_desc *gdp)
2582 {
2583         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2584         __u16 crc = 0;
2585         __le32 le_group = cpu_to_le32(block_group);
2586         struct ext4_sb_info *sbi = EXT4_SB(sb);
2587
2588         if (ext4_has_metadata_csum(sbi->s_sb)) {
2589                 /* Use new metadata_csum algorithm */
2590                 __u32 csum32;
2591                 __u16 dummy_csum = 0;
2592
2593                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2594                                      sizeof(le_group));
2595                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2596                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2597                                      sizeof(dummy_csum));
2598                 offset += sizeof(dummy_csum);
2599                 if (offset < sbi->s_desc_size)
2600                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2601                                              sbi->s_desc_size - offset);
2602
2603                 crc = csum32 & 0xFFFF;
2604                 goto out;
2605         }
2606
2607         /* old crc16 code */
2608         if (!ext4_has_feature_gdt_csum(sb))
2609                 return 0;
2610
2611         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2612         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2613         crc = crc16(crc, (__u8 *)gdp, offset);
2614         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2615         /* for checksum of struct ext4_group_desc do the rest...*/
2616         if (ext4_has_feature_64bit(sb) &&
2617             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2618                 crc = crc16(crc, (__u8 *)gdp + offset,
2619                             le16_to_cpu(sbi->s_es->s_desc_size) -
2620                                 offset);
2621
2622 out:
2623         return cpu_to_le16(crc);
2624 }
2625
2626 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2627                                 struct ext4_group_desc *gdp)
2628 {
2629         if (ext4_has_group_desc_csum(sb) &&
2630             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2631                 return 0;
2632
2633         return 1;
2634 }
2635
2636 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2637                               struct ext4_group_desc *gdp)
2638 {
2639         if (!ext4_has_group_desc_csum(sb))
2640                 return;
2641         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2642 }
2643
2644 /* Called at mount-time, super-block is locked */
2645 static int ext4_check_descriptors(struct super_block *sb,
2646                                   ext4_fsblk_t sb_block,
2647                                   ext4_group_t *first_not_zeroed)
2648 {
2649         struct ext4_sb_info *sbi = EXT4_SB(sb);
2650         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2651         ext4_fsblk_t last_block;
2652         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2653         ext4_fsblk_t block_bitmap;
2654         ext4_fsblk_t inode_bitmap;
2655         ext4_fsblk_t inode_table;
2656         int flexbg_flag = 0;
2657         ext4_group_t i, grp = sbi->s_groups_count;
2658
2659         if (ext4_has_feature_flex_bg(sb))
2660                 flexbg_flag = 1;
2661
2662         ext4_debug("Checking group descriptors");
2663
2664         for (i = 0; i < sbi->s_groups_count; i++) {
2665                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2666
2667                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2668                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2669                 else
2670                         last_block = first_block +
2671                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2672
2673                 if ((grp == sbi->s_groups_count) &&
2674                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2675                         grp = i;
2676
2677                 block_bitmap = ext4_block_bitmap(sb, gdp);
2678                 if (block_bitmap == sb_block) {
2679                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2680                                  "Block bitmap for group %u overlaps "
2681                                  "superblock", i);
2682                         if (!sb_rdonly(sb))
2683                                 return 0;
2684                 }
2685                 if (block_bitmap >= sb_block + 1 &&
2686                     block_bitmap <= last_bg_block) {
2687                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2688                                  "Block bitmap for group %u overlaps "
2689                                  "block group descriptors", i);
2690                         if (!sb_rdonly(sb))
2691                                 return 0;
2692                 }
2693                 if (block_bitmap < first_block || block_bitmap > last_block) {
2694                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2695                                "Block bitmap for group %u not in group "
2696                                "(block %llu)!", i, block_bitmap);
2697                         return 0;
2698                 }
2699                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2700                 if (inode_bitmap == sb_block) {
2701                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2702                                  "Inode bitmap for group %u overlaps "
2703                                  "superblock", i);
2704                         if (!sb_rdonly(sb))
2705                                 return 0;
2706                 }
2707                 if (inode_bitmap >= sb_block + 1 &&
2708                     inode_bitmap <= last_bg_block) {
2709                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2710                                  "Inode bitmap for group %u overlaps "
2711                                  "block group descriptors", i);
2712                         if (!sb_rdonly(sb))
2713                                 return 0;
2714                 }
2715                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2716                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2717                                "Inode bitmap for group %u not in group "
2718                                "(block %llu)!", i, inode_bitmap);
2719                         return 0;
2720                 }
2721                 inode_table = ext4_inode_table(sb, gdp);
2722                 if (inode_table == sb_block) {
2723                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2724                                  "Inode table for group %u overlaps "
2725                                  "superblock", i);
2726                         if (!sb_rdonly(sb))
2727                                 return 0;
2728                 }
2729                 if (inode_table >= sb_block + 1 &&
2730                     inode_table <= last_bg_block) {
2731                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2732                                  "Inode table for group %u overlaps "
2733                                  "block group descriptors", i);
2734                         if (!sb_rdonly(sb))
2735                                 return 0;
2736                 }
2737                 if (inode_table < first_block ||
2738                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2739                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2740                                "Inode table for group %u not in group "
2741                                "(block %llu)!", i, inode_table);
2742                         return 0;
2743                 }
2744                 ext4_lock_group(sb, i);
2745                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2746                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2747                                  "Checksum for group %u failed (%u!=%u)",
2748                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2749                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2750                         if (!sb_rdonly(sb)) {
2751                                 ext4_unlock_group(sb, i);
2752                                 return 0;
2753                         }
2754                 }
2755                 ext4_unlock_group(sb, i);
2756                 if (!flexbg_flag)
2757                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2758         }
2759         if (NULL != first_not_zeroed)
2760                 *first_not_zeroed = grp;
2761         return 1;
2762 }
2763
2764 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2765  * the superblock) which were deleted from all directories, but held open by
2766  * a process at the time of a crash.  We walk the list and try to delete these
2767  * inodes at recovery time (only with a read-write filesystem).
2768  *
2769  * In order to keep the orphan inode chain consistent during traversal (in
2770  * case of crash during recovery), we link each inode into the superblock
2771  * orphan list_head and handle it the same way as an inode deletion during
2772  * normal operation (which journals the operations for us).
2773  *
2774  * We only do an iget() and an iput() on each inode, which is very safe if we
2775  * accidentally point at an in-use or already deleted inode.  The worst that
2776  * can happen in this case is that we get a "bit already cleared" message from
2777  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2778  * e2fsck was run on this filesystem, and it must have already done the orphan
2779  * inode cleanup for us, so we can safely abort without any further action.
2780  */
2781 static void ext4_orphan_cleanup(struct super_block *sb,
2782                                 struct ext4_super_block *es)
2783 {
2784         unsigned int s_flags = sb->s_flags;
2785         int ret, nr_orphans = 0, nr_truncates = 0;
2786 #ifdef CONFIG_QUOTA
2787         int quota_update = 0;
2788         int i;
2789 #endif
2790         if (!es->s_last_orphan) {
2791                 jbd_debug(4, "no orphan inodes to clean up\n");
2792                 return;
2793         }
2794
2795         if (bdev_read_only(sb->s_bdev)) {
2796                 ext4_msg(sb, KERN_ERR, "write access "
2797                         "unavailable, skipping orphan cleanup");
2798                 return;
2799         }
2800
2801         /* Check if feature set would not allow a r/w mount */
2802         if (!ext4_feature_set_ok(sb, 0)) {
2803                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2804                          "unknown ROCOMPAT features");
2805                 return;
2806         }
2807
2808         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2809                 /* don't clear list on RO mount w/ errors */
2810                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2811                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2812                                   "clearing orphan list.\n");
2813                         es->s_last_orphan = 0;
2814                 }
2815                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2816                 return;
2817         }
2818
2819         if (s_flags & SB_RDONLY) {
2820                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2821                 sb->s_flags &= ~SB_RDONLY;
2822         }
2823 #ifdef CONFIG_QUOTA
2824         /* Needed for iput() to work correctly and not trash data */
2825         sb->s_flags |= SB_ACTIVE;
2826
2827         /*
2828          * Turn on quotas which were not enabled for read-only mounts if
2829          * filesystem has quota feature, so that they are updated correctly.
2830          */
2831         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2832                 int ret = ext4_enable_quotas(sb);
2833
2834                 if (!ret)
2835                         quota_update = 1;
2836                 else
2837                         ext4_msg(sb, KERN_ERR,
2838                                 "Cannot turn on quotas: error %d", ret);
2839         }
2840
2841         /* Turn on journaled quotas used for old sytle */
2842         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2843                 if (EXT4_SB(sb)->s_qf_names[i]) {
2844                         int ret = ext4_quota_on_mount(sb, i);
2845
2846                         if (!ret)
2847                                 quota_update = 1;
2848                         else
2849                                 ext4_msg(sb, KERN_ERR,
2850                                         "Cannot turn on journaled "
2851                                         "quota: type %d: error %d", i, ret);
2852                 }
2853         }
2854 #endif
2855
2856         while (es->s_last_orphan) {
2857                 struct inode *inode;
2858
2859                 /*
2860                  * We may have encountered an error during cleanup; if
2861                  * so, skip the rest.
2862                  */
2863                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2864                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2865                         es->s_last_orphan = 0;
2866                         break;
2867                 }
2868
2869                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2870                 if (IS_ERR(inode)) {
2871                         es->s_last_orphan = 0;
2872                         break;
2873                 }
2874
2875                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2876                 dquot_initialize(inode);
2877                 if (inode->i_nlink) {
2878                         if (test_opt(sb, DEBUG))
2879                                 ext4_msg(sb, KERN_DEBUG,
2880                                         "%s: truncating inode %lu to %lld bytes",
2881                                         __func__, inode->i_ino, inode->i_size);
2882                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2883                                   inode->i_ino, inode->i_size);
2884                         inode_lock(inode);
2885                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2886                         ret = ext4_truncate(inode);
2887                         if (ret)
2888                                 ext4_std_error(inode->i_sb, ret);
2889                         inode_unlock(inode);
2890                         nr_truncates++;
2891                 } else {
2892                         if (test_opt(sb, DEBUG))
2893                                 ext4_msg(sb, KERN_DEBUG,
2894                                         "%s: deleting unreferenced inode %lu",
2895                                         __func__, inode->i_ino);
2896                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2897                                   inode->i_ino);
2898                         nr_orphans++;
2899                 }
2900                 iput(inode);  /* The delete magic happens here! */
2901         }
2902
2903 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2904
2905         if (nr_orphans)
2906                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2907                        PLURAL(nr_orphans));
2908         if (nr_truncates)
2909                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2910                        PLURAL(nr_truncates));
2911 #ifdef CONFIG_QUOTA
2912         /* Turn off quotas if they were enabled for orphan cleanup */
2913         if (quota_update) {
2914                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2915                         if (sb_dqopt(sb)->files[i])
2916                                 dquot_quota_off(sb, i);
2917                 }
2918         }
2919 #endif
2920         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2921 }
2922
2923 /*
2924  * Maximal extent format file size.
2925  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2926  * extent format containers, within a sector_t, and within i_blocks
2927  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2928  * so that won't be a limiting factor.
2929  *
2930  * However there is other limiting factor. We do store extents in the form
2931  * of starting block and length, hence the resulting length of the extent
2932  * covering maximum file size must fit into on-disk format containers as
2933  * well. Given that length is always by 1 unit bigger than max unit (because
2934  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2935  *
2936  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2937  */
2938 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2939 {
2940         loff_t res;
2941         loff_t upper_limit = MAX_LFS_FILESIZE;
2942
2943         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
2944
2945         if (!has_huge_files) {
2946                 upper_limit = (1LL << 32) - 1;
2947
2948                 /* total blocks in file system block size */
2949                 upper_limit >>= (blkbits - 9);
2950                 upper_limit <<= blkbits;
2951         }
2952
2953         /*
2954          * 32-bit extent-start container, ee_block. We lower the maxbytes
2955          * by one fs block, so ee_len can cover the extent of maximum file
2956          * size
2957          */
2958         res = (1LL << 32) - 1;
2959         res <<= blkbits;
2960
2961         /* Sanity check against vm- & vfs- imposed limits */
2962         if (res > upper_limit)
2963                 res = upper_limit;
2964
2965         return res;
2966 }
2967
2968 /*
2969  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2970  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2971  * We need to be 1 filesystem block less than the 2^48 sector limit.
2972  */
2973 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2974 {
2975         loff_t res = EXT4_NDIR_BLOCKS;
2976         int meta_blocks;
2977         loff_t upper_limit;
2978         /* This is calculated to be the largest file size for a dense, block
2979          * mapped file such that the file's total number of 512-byte sectors,
2980          * including data and all indirect blocks, does not exceed (2^48 - 1).
2981          *
2982          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2983          * number of 512-byte sectors of the file.
2984          */
2985
2986         if (!has_huge_files) {
2987                 /*
2988                  * !has_huge_files or implies that the inode i_block field
2989                  * represents total file blocks in 2^32 512-byte sectors ==
2990                  * size of vfs inode i_blocks * 8
2991                  */
2992                 upper_limit = (1LL << 32) - 1;
2993
2994                 /* total blocks in file system block size */
2995                 upper_limit >>= (bits - 9);
2996
2997         } else {
2998                 /*
2999                  * We use 48 bit ext4_inode i_blocks
3000                  * With EXT4_HUGE_FILE_FL set the i_blocks
3001                  * represent total number of blocks in
3002                  * file system block size
3003                  */
3004                 upper_limit = (1LL << 48) - 1;
3005
3006         }
3007
3008         /* indirect blocks */
3009         meta_blocks = 1;
3010         /* double indirect blocks */
3011         meta_blocks += 1 + (1LL << (bits-2));
3012         /* tripple indirect blocks */
3013         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
3014
3015         upper_limit -= meta_blocks;
3016         upper_limit <<= bits;
3017
3018         res += 1LL << (bits-2);
3019         res += 1LL << (2*(bits-2));
3020         res += 1LL << (3*(bits-2));
3021         res <<= bits;
3022         if (res > upper_limit)
3023                 res = upper_limit;
3024
3025         if (res > MAX_LFS_FILESIZE)
3026                 res = MAX_LFS_FILESIZE;
3027
3028         return res;
3029 }
3030
3031 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3032                                    ext4_fsblk_t logical_sb_block, int nr)
3033 {
3034         struct ext4_sb_info *sbi = EXT4_SB(sb);
3035         ext4_group_t bg, first_meta_bg;
3036         int has_super = 0;
3037
3038         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3039
3040         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3041                 return logical_sb_block + nr + 1;
3042         bg = sbi->s_desc_per_block * nr;
3043         if (ext4_bg_has_super(sb, bg))
3044                 has_super = 1;
3045
3046         /*
3047          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3048          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3049          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3050          * compensate.
3051          */
3052         if (sb->s_blocksize == 1024 && nr == 0 &&
3053             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3054                 has_super++;
3055
3056         return (has_super + ext4_group_first_block_no(sb, bg));
3057 }
3058
3059 /**
3060  * ext4_get_stripe_size: Get the stripe size.
3061  * @sbi: In memory super block info
3062  *
3063  * If we have specified it via mount option, then
3064  * use the mount option value. If the value specified at mount time is
3065  * greater than the blocks per group use the super block value.
3066  * If the super block value is greater than blocks per group return 0.
3067  * Allocator needs it be less than blocks per group.
3068  *
3069  */
3070 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3071 {
3072         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3073         unsigned long stripe_width =
3074                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3075         int ret;
3076
3077         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3078                 ret = sbi->s_stripe;
3079         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3080                 ret = stripe_width;
3081         else if (stride && stride <= sbi->s_blocks_per_group)
3082                 ret = stride;
3083         else
3084                 ret = 0;
3085
3086         /*
3087          * If the stripe width is 1, this makes no sense and
3088          * we set it to 0 to turn off stripe handling code.
3089          */
3090         if (ret <= 1)
3091                 ret = 0;
3092
3093         return ret;
3094 }
3095
3096 /*
3097  * Check whether this filesystem can be mounted based on
3098  * the features present and the RDONLY/RDWR mount requested.
3099  * Returns 1 if this filesystem can be mounted as requested,
3100  * 0 if it cannot be.
3101  */
3102 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
3103 {
3104         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3105                 ext4_msg(sb, KERN_ERR,
3106                         "Couldn't mount because of "
3107                         "unsupported optional features (%x)",
3108                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3109                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3110                 return 0;
3111         }
3112
3113 #ifndef CONFIG_UNICODE
3114         if (ext4_has_feature_casefold(sb)) {
3115                 ext4_msg(sb, KERN_ERR,
3116                          "Filesystem with casefold feature cannot be "
3117                          "mounted without CONFIG_UNICODE");
3118                 return 0;
3119         }
3120 #endif
3121
3122         if (readonly)
3123                 return 1;
3124
3125         if (ext4_has_feature_readonly(sb)) {
3126                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3127                 sb->s_flags |= SB_RDONLY;
3128                 return 1;
3129         }
3130
3131         /* Check that feature set is OK for a read-write mount */
3132         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3133                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3134                          "unsupported optional features (%x)",
3135                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3136                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3137                 return 0;
3138         }
3139         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3140                 ext4_msg(sb, KERN_ERR,
3141                          "Can't support bigalloc feature without "
3142                          "extents feature\n");
3143                 return 0;
3144         }
3145
3146 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3147         if (!readonly && (ext4_has_feature_quota(sb) ||
3148                           ext4_has_feature_project(sb))) {
3149                 ext4_msg(sb, KERN_ERR,
3150                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3151                 return 0;
3152         }
3153 #endif  /* CONFIG_QUOTA */
3154         return 1;
3155 }
3156
3157 /*
3158  * This function is called once a day if we have errors logged
3159  * on the file system
3160  */
3161 static void print_daily_error_info(struct timer_list *t)
3162 {
3163         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3164         struct super_block *sb = sbi->s_sb;
3165         struct ext4_super_block *es = sbi->s_es;
3166
3167         if (es->s_error_count)
3168                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3169                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3170                          le32_to_cpu(es->s_error_count));
3171         if (es->s_first_error_time) {
3172                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3173                        sb->s_id,
3174                        ext4_get_tstamp(es, s_first_error_time),
3175                        (int) sizeof(es->s_first_error_func),
3176                        es->s_first_error_func,
3177                        le32_to_cpu(es->s_first_error_line));
3178                 if (es->s_first_error_ino)
3179                         printk(KERN_CONT ": inode %u",
3180                                le32_to_cpu(es->s_first_error_ino));
3181                 if (es->s_first_error_block)
3182                         printk(KERN_CONT ": block %llu", (unsigned long long)
3183                                le64_to_cpu(es->s_first_error_block));
3184                 printk(KERN_CONT "\n");
3185         }
3186         if (es->s_last_error_time) {
3187                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3188                        sb->s_id,
3189                        ext4_get_tstamp(es, s_last_error_time),
3190                        (int) sizeof(es->s_last_error_func),
3191                        es->s_last_error_func,
3192                        le32_to_cpu(es->s_last_error_line));
3193                 if (es->s_last_error_ino)
3194                         printk(KERN_CONT ": inode %u",
3195                                le32_to_cpu(es->s_last_error_ino));
3196                 if (es->s_last_error_block)
3197                         printk(KERN_CONT ": block %llu", (unsigned long long)
3198                                le64_to_cpu(es->s_last_error_block));
3199                 printk(KERN_CONT "\n");
3200         }
3201         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3202 }
3203
3204 /* Find next suitable group and run ext4_init_inode_table */
3205 static int ext4_run_li_request(struct ext4_li_request *elr)
3206 {
3207         struct ext4_group_desc *gdp = NULL;
3208         struct super_block *sb = elr->lr_super;
3209         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3210         ext4_group_t group = elr->lr_next_group;
3211         unsigned long timeout = 0;
3212         unsigned int prefetch_ios = 0;
3213         int ret = 0;
3214
3215         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3216                 elr->lr_next_group = ext4_mb_prefetch(sb, group,
3217                                 EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3218                 if (prefetch_ios)
3219                         ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3220                                               prefetch_ios);
3221                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3222                                             prefetch_ios);
3223                 if (group >= elr->lr_next_group) {
3224                         ret = 1;
3225                         if (elr->lr_first_not_zeroed != ngroups &&
3226                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3227                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3228                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3229                                 ret = 0;
3230                         }
3231                 }
3232                 return ret;
3233         }
3234
3235         for (; group < ngroups; group++) {
3236                 gdp = ext4_get_group_desc(sb, group, NULL);
3237                 if (!gdp) {
3238                         ret = 1;
3239                         break;
3240                 }
3241
3242                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3243                         break;
3244         }
3245
3246         if (group >= ngroups)
3247                 ret = 1;
3248
3249         if (!ret) {
3250                 timeout = jiffies;
3251                 ret = ext4_init_inode_table(sb, group,
3252                                             elr->lr_timeout ? 0 : 1);
3253                 trace_ext4_lazy_itable_init(sb, group);
3254                 if (elr->lr_timeout == 0) {
3255                         timeout = (jiffies - timeout) *
3256                                 EXT4_SB(elr->lr_super)->s_li_wait_mult;
3257                         elr->lr_timeout = timeout;
3258                 }
3259                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3260                 elr->lr_next_group = group + 1;
3261         }
3262         return ret;
3263 }
3264
3265 /*
3266  * Remove lr_request from the list_request and free the
3267  * request structure. Should be called with li_list_mtx held
3268  */
3269 static void ext4_remove_li_request(struct ext4_li_request *elr)
3270 {
3271         if (!elr)
3272                 return;
3273
3274         list_del(&elr->lr_request);
3275         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3276         kfree(elr);
3277 }
3278
3279 static void ext4_unregister_li_request(struct super_block *sb)
3280 {
3281         mutex_lock(&ext4_li_mtx);
3282         if (!ext4_li_info) {
3283                 mutex_unlock(&ext4_li_mtx);
3284                 return;
3285         }
3286
3287         mutex_lock(&ext4_li_info->li_list_mtx);
3288         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3289         mutex_unlock(&ext4_li_info->li_list_mtx);
3290         mutex_unlock(&ext4_li_mtx);
3291 }
3292
3293 static struct task_struct *ext4_lazyinit_task;
3294
3295 /*
3296  * This is the function where ext4lazyinit thread lives. It walks
3297  * through the request list searching for next scheduled filesystem.
3298  * When such a fs is found, run the lazy initialization request
3299  * (ext4_rn_li_request) and keep track of the time spend in this
3300  * function. Based on that time we compute next schedule time of
3301  * the request. When walking through the list is complete, compute
3302  * next waking time and put itself into sleep.
3303  */
3304 static int ext4_lazyinit_thread(void *arg)
3305 {
3306         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3307         struct list_head *pos, *n;
3308         struct ext4_li_request *elr;
3309         unsigned long next_wakeup, cur;
3310
3311         BUG_ON(NULL == eli);
3312
3313 cont_thread:
3314         while (true) {
3315                 next_wakeup = MAX_JIFFY_OFFSET;
3316
3317                 mutex_lock(&eli->li_list_mtx);
3318                 if (list_empty(&eli->li_request_list)) {
3319                         mutex_unlock(&eli->li_list_mtx);
3320                         goto exit_thread;
3321                 }
3322                 list_for_each_safe(pos, n, &eli->li_request_list) {
3323                         int err = 0;
3324                         int progress = 0;
3325                         elr = list_entry(pos, struct ext4_li_request,
3326                                          lr_request);
3327
3328                         if (time_before(jiffies, elr->lr_next_sched)) {
3329                                 if (time_before(elr->lr_next_sched, next_wakeup))
3330                                         next_wakeup = elr->lr_next_sched;
3331                                 continue;
3332                         }
3333                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3334                                 if (sb_start_write_trylock(elr->lr_super)) {
3335                                         progress = 1;
3336                                         /*
3337                                          * We hold sb->s_umount, sb can not
3338                                          * be removed from the list, it is
3339                                          * now safe to drop li_list_mtx
3340                                          */
3341                                         mutex_unlock(&eli->li_list_mtx);
3342                                         err = ext4_run_li_request(elr);
3343                                         sb_end_write(elr->lr_super);
3344                                         mutex_lock(&eli->li_list_mtx);
3345                                         n = pos->next;
3346                                 }
3347                                 up_read((&elr->lr_super->s_umount));
3348                         }
3349                         /* error, remove the lazy_init job */
3350                         if (err) {
3351                                 ext4_remove_li_request(elr);
3352                                 continue;
3353                         }
3354                         if (!progress) {
3355                                 elr->lr_next_sched = jiffies +
3356                                         (prandom_u32()
3357                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3358                         }
3359                         if (time_before(elr->lr_next_sched, next_wakeup))
3360                                 next_wakeup = elr->lr_next_sched;
3361                 }
3362                 mutex_unlock(&eli->li_list_mtx);
3363
3364                 try_to_freeze();
3365
3366                 cur = jiffies;
3367                 if ((time_after_eq(cur, next_wakeup)) ||
3368                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3369                         cond_resched();
3370                         continue;
3371                 }
3372
3373                 schedule_timeout_interruptible(next_wakeup - cur);
3374
3375                 if (kthread_should_stop()) {
3376                         ext4_clear_request_list();
3377                         goto exit_thread;
3378                 }
3379         }
3380
3381 exit_thread:
3382         /*
3383          * It looks like the request list is empty, but we need
3384          * to check it under the li_list_mtx lock, to prevent any
3385          * additions into it, and of course we should lock ext4_li_mtx
3386          * to atomically free the list and ext4_li_info, because at
3387          * this point another ext4 filesystem could be registering
3388          * new one.
3389          */
3390         mutex_lock(&ext4_li_mtx);
3391         mutex_lock(&eli->li_list_mtx);
3392         if (!list_empty(&eli->li_request_list)) {
3393                 mutex_unlock(&eli->li_list_mtx);
3394                 mutex_unlock(&ext4_li_mtx);
3395                 goto cont_thread;
3396         }
3397         mutex_unlock(&eli->li_list_mtx);
3398         kfree(ext4_li_info);
3399         ext4_li_info = NULL;
3400         mutex_unlock(&ext4_li_mtx);
3401
3402         return 0;
3403 }
3404
3405 static void ext4_clear_request_list(void)
3406 {
3407         struct list_head *pos, *n;
3408         struct ext4_li_request *elr;
3409
3410         mutex_lock(&ext4_li_info->li_list_mtx);
3411         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3412                 elr = list_entry(pos, struct ext4_li_request,
3413                                  lr_request);
3414                 ext4_remove_li_request(elr);
3415         }
3416         mutex_unlock(&ext4_li_info->li_list_mtx);
3417 }
3418
3419 static int ext4_run_lazyinit_thread(void)
3420 {
3421         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3422                                          ext4_li_info, "ext4lazyinit");
3423         if (IS_ERR(ext4_lazyinit_task)) {
3424                 int err = PTR_ERR(ext4_lazyinit_task);
3425                 ext4_clear_request_list();
3426                 kfree(ext4_li_info);
3427                 ext4_li_info = NULL;
3428                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3429                                  "initialization thread\n",
3430                                  err);
3431                 return err;
3432         }
3433         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3434         return 0;
3435 }
3436
3437 /*
3438  * Check whether it make sense to run itable init. thread or not.
3439  * If there is at least one uninitialized inode table, return
3440  * corresponding group number, else the loop goes through all
3441  * groups and return total number of groups.
3442  */
3443 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3444 {
3445         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3446         struct ext4_group_desc *gdp = NULL;
3447
3448         if (!ext4_has_group_desc_csum(sb))
3449                 return ngroups;
3450
3451         for (group = 0; group < ngroups; group++) {
3452                 gdp = ext4_get_group_desc(sb, group, NULL);
3453                 if (!gdp)
3454                         continue;
3455
3456                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3457                         break;
3458         }
3459
3460         return group;
3461 }
3462
3463 static int ext4_li_info_new(void)
3464 {
3465         struct ext4_lazy_init *eli = NULL;
3466
3467         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3468         if (!eli)
3469                 return -ENOMEM;
3470
3471         INIT_LIST_HEAD(&eli->li_request_list);
3472         mutex_init(&eli->li_list_mtx);
3473
3474         eli->li_state |= EXT4_LAZYINIT_QUIT;
3475
3476         ext4_li_info = eli;
3477
3478         return 0;
3479 }
3480
3481 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3482                                             ext4_group_t start)
3483 {
3484         struct ext4_li_request *elr;
3485
3486         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3487         if (!elr)
3488                 return NULL;
3489
3490         elr->lr_super = sb;
3491         elr->lr_first_not_zeroed = start;
3492         if (test_opt(sb, PREFETCH_BLOCK_BITMAPS))
3493                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3494         else {
3495                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3496                 elr->lr_next_group = start;
3497         }
3498
3499         /*
3500          * Randomize first schedule time of the request to
3501          * spread the inode table initialization requests
3502          * better.
3503          */
3504         elr->lr_next_sched = jiffies + (prandom_u32() %
3505                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3506         return elr;
3507 }
3508
3509 int ext4_register_li_request(struct super_block *sb,
3510                              ext4_group_t first_not_zeroed)
3511 {
3512         struct ext4_sb_info *sbi = EXT4_SB(sb);
3513         struct ext4_li_request *elr = NULL;
3514         ext4_group_t ngroups = sbi->s_groups_count;
3515         int ret = 0;
3516
3517         mutex_lock(&ext4_li_mtx);
3518         if (sbi->s_li_request != NULL) {
3519                 /*
3520                  * Reset timeout so it can be computed again, because
3521                  * s_li_wait_mult might have changed.
3522                  */
3523                 sbi->s_li_request->lr_timeout = 0;
3524                 goto out;
3525         }
3526
3527         if (!test_opt(sb, PREFETCH_BLOCK_BITMAPS) &&
3528             (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3529              !test_opt(sb, INIT_INODE_TABLE)))
3530                 goto out;
3531
3532         elr = ext4_li_request_new(sb, first_not_zeroed);
3533         if (!elr) {
3534                 ret = -ENOMEM;
3535                 goto out;
3536         }
3537
3538         if (NULL == ext4_li_info) {
3539                 ret = ext4_li_info_new();
3540                 if (ret)
3541                         goto out;
3542         }
3543
3544         mutex_lock(&ext4_li_info->li_list_mtx);
3545         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3546         mutex_unlock(&ext4_li_info->li_list_mtx);
3547
3548         sbi->s_li_request = elr;
3549         /*
3550          * set elr to NULL here since it has been inserted to
3551          * the request_list and the removal and free of it is
3552          * handled by ext4_clear_request_list from now on.
3553          */
3554         elr = NULL;
3555
3556         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3557                 ret = ext4_run_lazyinit_thread();
3558                 if (ret)
3559                         goto out;
3560         }
3561 out:
3562         mutex_unlock(&ext4_li_mtx);
3563         if (ret)
3564                 kfree(elr);
3565         return ret;
3566 }
3567
3568 /*
3569  * We do not need to lock anything since this is called on
3570  * module unload.
3571  */
3572 static void ext4_destroy_lazyinit_thread(void)
3573 {
3574         /*
3575          * If thread exited earlier
3576          * there's nothing to be done.
3577          */
3578         if (!ext4_li_info || !ext4_lazyinit_task)
3579                 return;
3580
3581         kthread_stop(ext4_lazyinit_task);
3582 }
3583
3584 static int set_journal_csum_feature_set(struct super_block *sb)
3585 {
3586         int ret = 1;
3587         int compat, incompat;
3588         struct ext4_sb_info *sbi = EXT4_SB(sb);
3589
3590         if (ext4_has_metadata_csum(sb)) {
3591                 /* journal checksum v3 */
3592                 compat = 0;
3593                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3594         } else {
3595                 /* journal checksum v1 */
3596                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3597                 incompat = 0;
3598         }
3599
3600         jbd2_journal_clear_features(sbi->s_journal,
3601                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3602                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3603                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3604         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3605                 ret = jbd2_journal_set_features(sbi->s_journal,
3606                                 compat, 0,
3607                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3608                                 incompat);
3609         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3610                 ret = jbd2_journal_set_features(sbi->s_journal,
3611                                 compat, 0,
3612                                 incompat);
3613                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3614                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3615         } else {
3616                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3617                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3618         }
3619
3620         return ret;
3621 }
3622
3623 /*
3624  * Note: calculating the overhead so we can be compatible with
3625  * historical BSD practice is quite difficult in the face of
3626  * clusters/bigalloc.  This is because multiple metadata blocks from
3627  * different block group can end up in the same allocation cluster.
3628  * Calculating the exact overhead in the face of clustered allocation
3629  * requires either O(all block bitmaps) in memory or O(number of block
3630  * groups**2) in time.  We will still calculate the superblock for
3631  * older file systems --- and if we come across with a bigalloc file
3632  * system with zero in s_overhead_clusters the estimate will be close to
3633  * correct especially for very large cluster sizes --- but for newer
3634  * file systems, it's better to calculate this figure once at mkfs
3635  * time, and store it in the superblock.  If the superblock value is
3636  * present (even for non-bigalloc file systems), we will use it.
3637  */
3638 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3639                           char *buf)
3640 {
3641         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3642         struct ext4_group_desc  *gdp;
3643         ext4_fsblk_t            first_block, last_block, b;
3644         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3645         int                     s, j, count = 0;
3646
3647         if (!ext4_has_feature_bigalloc(sb))
3648                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3649                         sbi->s_itb_per_group + 2);
3650
3651         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3652                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3653         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3654         for (i = 0; i < ngroups; i++) {
3655                 gdp = ext4_get_group_desc(sb, i, NULL);
3656                 b = ext4_block_bitmap(sb, gdp);
3657                 if (b >= first_block && b <= last_block) {
3658                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3659                         count++;
3660                 }
3661                 b = ext4_inode_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_table(sb, gdp);
3667                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3668                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3669                                 int c = EXT4_B2C(sbi, b - first_block);
3670                                 ext4_set_bit(c, buf);
3671                                 count++;
3672                         }
3673                 if (i != grp)
3674                         continue;
3675                 s = 0;
3676                 if (ext4_bg_has_super(sb, grp)) {
3677                         ext4_set_bit(s++, buf);
3678                         count++;
3679                 }
3680                 j = ext4_bg_num_gdb(sb, grp);
3681                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3682                         ext4_error(sb, "Invalid number of block group "
3683                                    "descriptor blocks: %d", j);
3684                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3685                 }
3686                 count += j;
3687                 for (; j > 0; j--)
3688                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3689         }
3690         if (!count)
3691                 return 0;
3692         return EXT4_CLUSTERS_PER_GROUP(sb) -
3693                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3694 }
3695
3696 /*
3697  * Compute the overhead and stash it in sbi->s_overhead
3698  */
3699 int ext4_calculate_overhead(struct super_block *sb)
3700 {
3701         struct ext4_sb_info *sbi = EXT4_SB(sb);
3702         struct ext4_super_block *es = sbi->s_es;
3703         struct inode *j_inode;
3704         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3705         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3706         ext4_fsblk_t overhead = 0;
3707         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3708
3709         if (!buf)
3710                 return -ENOMEM;
3711
3712         /*
3713          * Compute the overhead (FS structures).  This is constant
3714          * for a given filesystem unless the number of block groups
3715          * changes so we cache the previous value until it does.
3716          */
3717
3718         /*
3719          * All of the blocks before first_data_block are overhead
3720          */
3721         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3722
3723         /*
3724          * Add the overhead found in each block group
3725          */
3726         for (i = 0; i < ngroups; i++) {
3727                 int blks;
3728
3729                 blks = count_overhead(sb, i, buf);
3730                 overhead += blks;
3731                 if (blks)
3732                         memset(buf, 0, PAGE_SIZE);
3733                 cond_resched();
3734         }
3735
3736         /*
3737          * Add the internal journal blocks whether the journal has been
3738          * loaded or not
3739          */
3740         if (sbi->s_journal && !sbi->journal_bdev)
3741                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3742         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3743                 /* j_inum for internal journal is non-zero */
3744                 j_inode = ext4_get_journal_inode(sb, j_inum);
3745                 if (j_inode) {
3746                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3747                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3748                         iput(j_inode);
3749                 } else {
3750                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3751                 }
3752         }
3753         sbi->s_overhead = overhead;
3754         smp_wmb();
3755         free_page((unsigned long) buf);
3756         return 0;
3757 }
3758
3759 static void ext4_set_resv_clusters(struct super_block *sb)
3760 {
3761         ext4_fsblk_t resv_clusters;
3762         struct ext4_sb_info *sbi = EXT4_SB(sb);
3763
3764         /*
3765          * There's no need to reserve anything when we aren't using extents.
3766          * The space estimates are exact, there are no unwritten extents,
3767          * hole punching doesn't need new metadata... This is needed especially
3768          * to keep ext2/3 backward compatibility.
3769          */
3770         if (!ext4_has_feature_extents(sb))
3771                 return;
3772         /*
3773          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3774          * This should cover the situations where we can not afford to run
3775          * out of space like for example punch hole, or converting
3776          * unwritten extents in delalloc path. In most cases such
3777          * allocation would require 1, or 2 blocks, higher numbers are
3778          * very rare.
3779          */
3780         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3781                          sbi->s_cluster_bits);
3782
3783         do_div(resv_clusters, 50);
3784         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3785
3786         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3787 }
3788
3789 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3790 {
3791         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3792         char *orig_data = kstrdup(data, GFP_KERNEL);
3793         struct buffer_head *bh, **group_desc;
3794         struct ext4_super_block *es = NULL;
3795         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3796         struct flex_groups **flex_groups;
3797         ext4_fsblk_t block;
3798         ext4_fsblk_t sb_block = get_sb_block(&data);
3799         ext4_fsblk_t logical_sb_block;
3800         unsigned long offset = 0;
3801         unsigned long journal_devnum = 0;
3802         unsigned long def_mount_opts;
3803         struct inode *root;
3804         const char *descr;
3805         int ret = -ENOMEM;
3806         int blocksize, clustersize;
3807         unsigned int db_count;
3808         unsigned int i;
3809         int needs_recovery, has_huge_files;
3810         __u64 blocks_count;
3811         int err = 0;
3812         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3813         ext4_group_t first_not_zeroed;
3814
3815         if ((data && !orig_data) || !sbi)
3816                 goto out_free_base;
3817
3818         sbi->s_daxdev = dax_dev;
3819         sbi->s_blockgroup_lock =
3820                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3821         if (!sbi->s_blockgroup_lock)
3822                 goto out_free_base;
3823
3824         sb->s_fs_info = sbi;
3825         sbi->s_sb = sb;
3826         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3827         sbi->s_sb_block = sb_block;
3828         if (sb->s_bdev->bd_part)
3829                 sbi->s_sectors_written_start =
3830                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
3831
3832         /* Cleanup superblock name */
3833         strreplace(sb->s_id, '/', '!');
3834
3835         /* -EINVAL is default */
3836         ret = -EINVAL;
3837         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3838         if (!blocksize) {
3839                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3840                 goto out_fail;
3841         }
3842
3843         /*
3844          * The ext4 superblock will not be buffer aligned for other than 1kB
3845          * block sizes.  We need to calculate the offset from buffer start.
3846          */
3847         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3848                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3849                 offset = do_div(logical_sb_block, blocksize);
3850         } else {
3851                 logical_sb_block = sb_block;
3852         }
3853
3854         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3855                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3856                 goto out_fail;
3857         }
3858         /*
3859          * Note: s_es must be initialized as soon as possible because
3860          *       some ext4 macro-instructions depend on its value
3861          */
3862         es = (struct ext4_super_block *) (bh->b_data + offset);
3863         sbi->s_es = es;
3864         sb->s_magic = le16_to_cpu(es->s_magic);
3865         if (sb->s_magic != EXT4_SUPER_MAGIC)
3866                 goto cantfind_ext4;
3867         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3868
3869         /* Warn if metadata_csum and gdt_csum are both set. */
3870         if (ext4_has_feature_metadata_csum(sb) &&
3871             ext4_has_feature_gdt_csum(sb))
3872                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3873                              "redundant flags; please run fsck.");
3874
3875         /* Check for a known checksum algorithm */
3876         if (!ext4_verify_csum_type(sb, es)) {
3877                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3878                          "unknown checksum algorithm.");
3879                 silent = 1;
3880                 goto cantfind_ext4;
3881         }
3882
3883         /* Load the checksum driver */
3884         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3885         if (IS_ERR(sbi->s_chksum_driver)) {
3886                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3887                 ret = PTR_ERR(sbi->s_chksum_driver);
3888                 sbi->s_chksum_driver = NULL;
3889                 goto failed_mount;
3890         }
3891
3892         /* Check superblock checksum */
3893         if (!ext4_superblock_csum_verify(sb, es)) {
3894                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3895                          "invalid superblock checksum.  Run e2fsck?");
3896                 silent = 1;
3897                 ret = -EFSBADCRC;
3898                 goto cantfind_ext4;
3899         }
3900
3901         /* Precompute checksum seed for all metadata */
3902         if (ext4_has_feature_csum_seed(sb))
3903                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3904         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3905                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3906                                                sizeof(es->s_uuid));
3907
3908         /* Set defaults before we parse the mount options */
3909         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3910         set_opt(sb, INIT_INODE_TABLE);
3911         if (def_mount_opts & EXT4_DEFM_DEBUG)
3912                 set_opt(sb, DEBUG);
3913         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3914                 set_opt(sb, GRPID);
3915         if (def_mount_opts & EXT4_DEFM_UID16)
3916                 set_opt(sb, NO_UID32);
3917         /* xattr user namespace & acls are now defaulted on */
3918         set_opt(sb, XATTR_USER);
3919 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3920         set_opt(sb, POSIX_ACL);
3921 #endif
3922         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3923         if (ext4_has_metadata_csum(sb))
3924                 set_opt(sb, JOURNAL_CHECKSUM);
3925
3926         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3927                 set_opt(sb, JOURNAL_DATA);
3928         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3929                 set_opt(sb, ORDERED_DATA);
3930         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3931                 set_opt(sb, WRITEBACK_DATA);
3932
3933         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3934                 set_opt(sb, ERRORS_PANIC);
3935         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3936                 set_opt(sb, ERRORS_CONT);
3937         else
3938                 set_opt(sb, ERRORS_RO);
3939         /* block_validity enabled by default; disable with noblock_validity */
3940         set_opt(sb, BLOCK_VALIDITY);
3941         if (def_mount_opts & EXT4_DEFM_DISCARD)
3942                 set_opt(sb, DISCARD);
3943
3944         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3945         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3946         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3947         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3948         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3949
3950         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3951                 set_opt(sb, BARRIER);
3952
3953         /*
3954          * enable delayed allocation by default
3955          * Use -o nodelalloc to turn it off
3956          */
3957         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3958             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3959                 set_opt(sb, DELALLOC);
3960
3961         /*
3962          * set default s_li_wait_mult for lazyinit, for the case there is
3963          * no mount option specified.
3964          */
3965         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3966
3967         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3968
3969         if (blocksize == PAGE_SIZE)
3970                 set_opt(sb, DIOREAD_NOLOCK);
3971
3972         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3973             blocksize > EXT4_MAX_BLOCK_SIZE) {
3974                 ext4_msg(sb, KERN_ERR,
3975                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3976                          blocksize, le32_to_cpu(es->s_log_block_size));
3977                 goto failed_mount;
3978         }
3979
3980         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3981                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3982                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3983         } else {
3984                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3985                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3986                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
3987                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
3988                                  sbi->s_first_ino);
3989                         goto failed_mount;
3990                 }
3991                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3992                     (!is_power_of_2(sbi->s_inode_size)) ||
3993                     (sbi->s_inode_size > blocksize)) {
3994                         ext4_msg(sb, KERN_ERR,
3995                                "unsupported inode size: %d",
3996                                sbi->s_inode_size);
3997                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
3998                         goto failed_mount;
3999                 }
4000                 /*
4001                  * i_atime_extra is the last extra field available for
4002                  * [acm]times in struct ext4_inode. Checking for that
4003                  * field should suffice to ensure we have extra space
4004                  * for all three.
4005                  */
4006                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4007                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4008                         sb->s_time_gran = 1;
4009                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4010                 } else {
4011                         sb->s_time_gran = NSEC_PER_SEC;
4012                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4013                 }
4014                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4015         }
4016         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4017                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4018                         EXT4_GOOD_OLD_INODE_SIZE;
4019                 if (ext4_has_feature_extra_isize(sb)) {
4020                         unsigned v, max = (sbi->s_inode_size -
4021                                            EXT4_GOOD_OLD_INODE_SIZE);
4022
4023                         v = le16_to_cpu(es->s_want_extra_isize);
4024                         if (v > max) {
4025                                 ext4_msg(sb, KERN_ERR,
4026                                          "bad s_want_extra_isize: %d", v);
4027                                 goto failed_mount;
4028                         }
4029                         if (sbi->s_want_extra_isize < v)
4030                                 sbi->s_want_extra_isize = v;
4031
4032                         v = le16_to_cpu(es->s_min_extra_isize);
4033                         if (v > max) {
4034                                 ext4_msg(sb, KERN_ERR,
4035                                          "bad s_min_extra_isize: %d", v);
4036                                 goto failed_mount;
4037                         }
4038                         if (sbi->s_want_extra_isize < v)
4039                                 sbi->s_want_extra_isize = v;
4040                 }
4041         }
4042
4043         if (sbi->s_es->s_mount_opts[0]) {
4044                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
4045                                               sizeof(sbi->s_es->s_mount_opts),
4046                                               GFP_KERNEL);
4047                 if (!s_mount_opts)
4048                         goto failed_mount;
4049                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
4050                                    &journal_ioprio, 0)) {
4051                         ext4_msg(sb, KERN_WARNING,
4052                                  "failed to parse options in superblock: %s",
4053                                  s_mount_opts);
4054                 }
4055                 kfree(s_mount_opts);
4056         }
4057         sbi->s_def_mount_opt = sbi->s_mount_opt;
4058         if (!parse_options((char *) data, sb, &journal_devnum,
4059                            &journal_ioprio, 0))
4060                 goto failed_mount;
4061
4062 #ifdef CONFIG_UNICODE
4063         if (ext4_has_feature_casefold(sb) && !sbi->s_encoding) {
4064                 const struct ext4_sb_encodings *encoding_info;
4065                 struct unicode_map *encoding;
4066                 __u16 encoding_flags;
4067
4068                 if (ext4_has_feature_encrypt(sb)) {
4069                         ext4_msg(sb, KERN_ERR,
4070                                  "Can't mount with encoding and encryption");
4071                         goto failed_mount;
4072                 }
4073
4074                 if (ext4_sb_read_encoding(es, &encoding_info,
4075                                           &encoding_flags)) {
4076                         ext4_msg(sb, KERN_ERR,
4077                                  "Encoding requested by superblock is unknown");
4078                         goto failed_mount;
4079                 }
4080
4081                 encoding = utf8_load(encoding_info->version);
4082                 if (IS_ERR(encoding)) {
4083                         ext4_msg(sb, KERN_ERR,
4084                                  "can't mount with superblock charset: %s-%s "
4085                                  "not supported by the kernel. flags: 0x%x.",
4086                                  encoding_info->name, encoding_info->version,
4087                                  encoding_flags);
4088                         goto failed_mount;
4089                 }
4090                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4091                          "%s-%s with flags 0x%hx", encoding_info->name,
4092                          encoding_info->version?:"\b", encoding_flags);
4093
4094                 sbi->s_encoding = encoding;
4095                 sbi->s_encoding_flags = encoding_flags;
4096         }
4097 #endif
4098
4099         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4100                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, and O_DIRECT support!\n");
4101                 /* can't mount with both data=journal and dioread_nolock. */
4102                 clear_opt(sb, DIOREAD_NOLOCK);
4103                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4104                         ext4_msg(sb, KERN_ERR, "can't mount with "
4105                                  "both data=journal and delalloc");
4106                         goto failed_mount;
4107                 }
4108                 if (test_opt(sb, DAX_ALWAYS)) {
4109                         ext4_msg(sb, KERN_ERR, "can't mount with "
4110                                  "both data=journal and dax");
4111                         goto failed_mount;
4112                 }
4113                 if (ext4_has_feature_encrypt(sb)) {
4114                         ext4_msg(sb, KERN_WARNING,
4115                                  "encrypted files will use data=ordered "
4116                                  "instead of data journaling mode");
4117                 }
4118                 if (test_opt(sb, DELALLOC))
4119                         clear_opt(sb, DELALLOC);
4120         } else {
4121                 sb->s_iflags |= SB_I_CGROUPWB;
4122         }
4123
4124         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4125                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4126
4127         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4128             (ext4_has_compat_features(sb) ||
4129              ext4_has_ro_compat_features(sb) ||
4130              ext4_has_incompat_features(sb)))
4131                 ext4_msg(sb, KERN_WARNING,
4132                        "feature flags set on rev 0 fs, "
4133                        "running e2fsck is recommended");
4134
4135         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4136                 set_opt2(sb, HURD_COMPAT);
4137                 if (ext4_has_feature_64bit(sb)) {
4138                         ext4_msg(sb, KERN_ERR,
4139                                  "The Hurd can't support 64-bit file systems");
4140                         goto failed_mount;
4141                 }
4142
4143                 /*
4144                  * ea_inode feature uses l_i_version field which is not
4145                  * available in HURD_COMPAT mode.
4146                  */
4147                 if (ext4_has_feature_ea_inode(sb)) {
4148                         ext4_msg(sb, KERN_ERR,
4149                                  "ea_inode feature is not supported for Hurd");
4150                         goto failed_mount;
4151                 }
4152         }
4153
4154         if (IS_EXT2_SB(sb)) {
4155                 if (ext2_feature_set_ok(sb))
4156                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4157                                  "using the ext4 subsystem");
4158                 else {
4159                         /*
4160                          * If we're probing be silent, if this looks like
4161                          * it's actually an ext[34] filesystem.
4162                          */
4163                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4164                                 goto failed_mount;
4165                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4166                                  "to feature incompatibilities");
4167                         goto failed_mount;
4168                 }
4169         }
4170
4171         if (IS_EXT3_SB(sb)) {
4172                 if (ext3_feature_set_ok(sb))
4173                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4174                                  "using the ext4 subsystem");
4175                 else {
4176                         /*
4177                          * If we're probing be silent, if this looks like
4178                          * it's actually an ext4 filesystem.
4179                          */
4180                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4181                                 goto failed_mount;
4182                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4183                                  "to feature incompatibilities");
4184                         goto failed_mount;
4185                 }
4186         }
4187
4188         /*
4189          * Check feature flags regardless of the revision level, since we
4190          * previously didn't change the revision level when setting the flags,
4191          * so there is a chance incompat flags are set on a rev 0 filesystem.
4192          */
4193         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4194                 goto failed_mount;
4195
4196         if (le32_to_cpu(es->s_log_block_size) >
4197             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4198                 ext4_msg(sb, KERN_ERR,
4199                          "Invalid log block size: %u",
4200                          le32_to_cpu(es->s_log_block_size));
4201                 goto failed_mount;
4202         }
4203         if (le32_to_cpu(es->s_log_cluster_size) >
4204             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4205                 ext4_msg(sb, KERN_ERR,
4206                          "Invalid log cluster size: %u",
4207                          le32_to_cpu(es->s_log_cluster_size));
4208                 goto failed_mount;
4209         }
4210
4211         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4212                 ext4_msg(sb, KERN_ERR,
4213                          "Number of reserved GDT blocks insanely large: %d",
4214                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4215                 goto failed_mount;
4216         }
4217
4218         if (bdev_dax_supported(sb->s_bdev, blocksize))
4219                 set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4220
4221         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4222                 if (ext4_has_feature_inline_data(sb)) {
4223                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4224                                         " that may contain inline data");
4225                         goto failed_mount;
4226                 }
4227                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4228                         ext4_msg(sb, KERN_ERR,
4229                                 "DAX unsupported by block device.");
4230                         goto failed_mount;
4231                 }
4232         }
4233
4234         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4235                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4236                          es->s_encryption_level);
4237                 goto failed_mount;
4238         }
4239
4240         if (sb->s_blocksize != blocksize) {
4241                 /* Validate the filesystem blocksize */
4242                 if (!sb_set_blocksize(sb, blocksize)) {
4243                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4244                                         blocksize);
4245                         goto failed_mount;
4246                 }
4247
4248                 brelse(bh);
4249                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4250                 offset = do_div(logical_sb_block, blocksize);
4251                 bh = sb_bread_unmovable(sb, logical_sb_block);
4252                 if (!bh) {
4253                         ext4_msg(sb, KERN_ERR,
4254                                "Can't read superblock on 2nd try");
4255                         goto failed_mount;
4256                 }
4257                 es = (struct ext4_super_block *)(bh->b_data + offset);
4258                 sbi->s_es = es;
4259                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4260                         ext4_msg(sb, KERN_ERR,
4261                                "Magic mismatch, very weird!");
4262                         goto failed_mount;
4263                 }
4264         }
4265
4266         has_huge_files = ext4_has_feature_huge_file(sb);
4267         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4268                                                       has_huge_files);
4269         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4270
4271         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4272         if (ext4_has_feature_64bit(sb)) {
4273                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4274                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4275                     !is_power_of_2(sbi->s_desc_size)) {
4276                         ext4_msg(sb, KERN_ERR,
4277                                "unsupported descriptor size %lu",
4278                                sbi->s_desc_size);
4279                         goto failed_mount;
4280                 }
4281         } else
4282                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4283
4284         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4285         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4286
4287         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4288         if (sbi->s_inodes_per_block == 0)
4289                 goto cantfind_ext4;
4290         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4291             sbi->s_inodes_per_group > blocksize * 8) {
4292                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4293                          sbi->s_inodes_per_group);
4294                 goto failed_mount;
4295         }
4296         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4297                                         sbi->s_inodes_per_block;
4298         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4299         sbi->s_sbh = bh;
4300         sbi->s_mount_state = le16_to_cpu(es->s_state);
4301         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4302         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4303
4304         for (i = 0; i < 4; i++)
4305                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4306         sbi->s_def_hash_version = es->s_def_hash_version;
4307         if (ext4_has_feature_dir_index(sb)) {
4308                 i = le32_to_cpu(es->s_flags);
4309                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4310                         sbi->s_hash_unsigned = 3;
4311                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4312 #ifdef __CHAR_UNSIGNED__
4313                         if (!sb_rdonly(sb))
4314                                 es->s_flags |=
4315                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4316                         sbi->s_hash_unsigned = 3;
4317 #else
4318                         if (!sb_rdonly(sb))
4319                                 es->s_flags |=
4320                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4321 #endif
4322                 }
4323         }
4324
4325         /* Handle clustersize */
4326         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4327         if (ext4_has_feature_bigalloc(sb)) {
4328                 if (clustersize < blocksize) {
4329                         ext4_msg(sb, KERN_ERR,
4330                                  "cluster size (%d) smaller than "
4331                                  "block size (%d)", clustersize, blocksize);
4332                         goto failed_mount;
4333                 }
4334                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4335                         le32_to_cpu(es->s_log_block_size);
4336                 sbi->s_clusters_per_group =
4337                         le32_to_cpu(es->s_clusters_per_group);
4338                 if (sbi->s_clusters_per_group > blocksize * 8) {
4339                         ext4_msg(sb, KERN_ERR,
4340                                  "#clusters per group too big: %lu",
4341                                  sbi->s_clusters_per_group);
4342                         goto failed_mount;
4343                 }
4344                 if (sbi->s_blocks_per_group !=
4345                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4346                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4347                                  "clusters per group (%lu) inconsistent",
4348                                  sbi->s_blocks_per_group,
4349                                  sbi->s_clusters_per_group);
4350                         goto failed_mount;
4351                 }
4352         } else {
4353                 if (clustersize != blocksize) {
4354                         ext4_msg(sb, KERN_ERR,
4355                                  "fragment/cluster size (%d) != "
4356                                  "block size (%d)", clustersize, blocksize);
4357                         goto failed_mount;
4358                 }
4359                 if (sbi->s_blocks_per_group > blocksize * 8) {
4360                         ext4_msg(sb, KERN_ERR,
4361                                  "#blocks per group too big: %lu",
4362                                  sbi->s_blocks_per_group);
4363                         goto failed_mount;
4364                 }
4365                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4366                 sbi->s_cluster_bits = 0;
4367         }
4368         sbi->s_cluster_ratio = clustersize / blocksize;
4369
4370         /* Do we have standard group size of clustersize * 8 blocks ? */
4371         if (sbi->s_blocks_per_group == clustersize << 3)
4372                 set_opt2(sb, STD_GROUP_SIZE);
4373
4374         /*
4375          * Test whether we have more sectors than will fit in sector_t,
4376          * and whether the max offset is addressable by the page cache.
4377          */
4378         err = generic_check_addressable(sb->s_blocksize_bits,
4379                                         ext4_blocks_count(es));
4380         if (err) {
4381                 ext4_msg(sb, KERN_ERR, "filesystem"
4382                          " too large to mount safely on this system");
4383                 goto failed_mount;
4384         }
4385
4386         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4387                 goto cantfind_ext4;
4388
4389         /* check blocks count against device size */
4390         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4391         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4392                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4393                        "exceeds size of device (%llu blocks)",
4394                        ext4_blocks_count(es), blocks_count);
4395                 goto failed_mount;
4396         }
4397
4398         /*
4399          * It makes no sense for the first data block to be beyond the end
4400          * of the filesystem.
4401          */
4402         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4403                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4404                          "block %u is beyond end of filesystem (%llu)",
4405                          le32_to_cpu(es->s_first_data_block),
4406                          ext4_blocks_count(es));
4407                 goto failed_mount;
4408         }
4409         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4410             (sbi->s_cluster_ratio == 1)) {
4411                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4412                          "block is 0 with a 1k block and cluster size");
4413                 goto failed_mount;
4414         }
4415
4416         blocks_count = (ext4_blocks_count(es) -
4417                         le32_to_cpu(es->s_first_data_block) +
4418                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4419         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4420         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4421                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4422                        "(block count %llu, first data block %u, "
4423                        "blocks per group %lu)", blocks_count,
4424                        ext4_blocks_count(es),
4425                        le32_to_cpu(es->s_first_data_block),
4426                        EXT4_BLOCKS_PER_GROUP(sb));
4427                 goto failed_mount;
4428         }
4429         sbi->s_groups_count = blocks_count;
4430         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4431                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4432         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4433             le32_to_cpu(es->s_inodes_count)) {
4434                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4435                          le32_to_cpu(es->s_inodes_count),
4436                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4437                 ret = -EINVAL;
4438                 goto failed_mount;
4439         }
4440         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4441                    EXT4_DESC_PER_BLOCK(sb);
4442         if (ext4_has_feature_meta_bg(sb)) {
4443                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4444                         ext4_msg(sb, KERN_WARNING,
4445                                  "first meta block group too large: %u "
4446                                  "(group descriptor block count %u)",
4447                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4448                         goto failed_mount;
4449                 }
4450         }
4451         rcu_assign_pointer(sbi->s_group_desc,
4452                            kvmalloc_array(db_count,
4453                                           sizeof(struct buffer_head *),
4454                                           GFP_KERNEL));
4455         if (sbi->s_group_desc == NULL) {
4456                 ext4_msg(sb, KERN_ERR, "not enough memory");
4457                 ret = -ENOMEM;
4458                 goto failed_mount;
4459         }
4460
4461         bgl_lock_init(sbi->s_blockgroup_lock);
4462
4463         /* Pre-read the descriptors into the buffer cache */
4464         for (i = 0; i < db_count; i++) {
4465                 block = descriptor_loc(sb, logical_sb_block, i);
4466                 sb_breadahead_unmovable(sb, block);
4467         }
4468
4469         for (i = 0; i < db_count; i++) {
4470                 struct buffer_head *bh;
4471
4472                 block = descriptor_loc(sb, logical_sb_block, i);
4473                 bh = sb_bread_unmovable(sb, block);
4474                 if (!bh) {
4475                         ext4_msg(sb, KERN_ERR,
4476                                "can't read group descriptor %d", i);
4477                         db_count = i;
4478                         goto failed_mount2;
4479                 }
4480                 rcu_read_lock();
4481                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4482                 rcu_read_unlock();
4483         }
4484         sbi->s_gdb_count = db_count;
4485         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4486                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4487                 ret = -EFSCORRUPTED;
4488                 goto failed_mount2;
4489         }
4490
4491         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4492
4493         /* Register extent status tree shrinker */
4494         if (ext4_es_register_shrinker(sbi))
4495                 goto failed_mount3;
4496
4497         sbi->s_stripe = ext4_get_stripe_size(sbi);
4498         sbi->s_extent_max_zeroout_kb = 32;
4499
4500         /*
4501          * set up enough so that it can read an inode
4502          */
4503         sb->s_op = &ext4_sops;
4504         sb->s_export_op = &ext4_export_ops;
4505         sb->s_xattr = ext4_xattr_handlers;
4506 #ifdef CONFIG_FS_ENCRYPTION
4507         sb->s_cop = &ext4_cryptops;
4508 #endif
4509 #ifdef CONFIG_FS_VERITY
4510         sb->s_vop = &ext4_verityops;
4511 #endif
4512 #ifdef CONFIG_QUOTA
4513         sb->dq_op = &ext4_quota_operations;
4514         if (ext4_has_feature_quota(sb))
4515                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4516         else
4517                 sb->s_qcop = &ext4_qctl_operations;
4518         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4519 #endif
4520         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4521
4522         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4523         mutex_init(&sbi->s_orphan_lock);
4524
4525         sb->s_root = NULL;
4526
4527         needs_recovery = (es->s_last_orphan != 0 ||
4528                           ext4_has_feature_journal_needs_recovery(sb));
4529
4530         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4531                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4532                         goto failed_mount3a;
4533
4534         /*
4535          * The first inode we look at is the journal inode.  Don't try
4536          * root first: it may be modified in the journal!
4537          */
4538         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4539                 err = ext4_load_journal(sb, es, journal_devnum);
4540                 if (err)
4541                         goto failed_mount3a;
4542         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4543                    ext4_has_feature_journal_needs_recovery(sb)) {
4544                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4545                        "suppressed and not mounted read-only");
4546                 goto failed_mount_wq;
4547         } else {
4548                 /* Nojournal mode, all journal mount options are illegal */
4549                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4550                         ext4_msg(sb, KERN_ERR, "can't mount with "
4551                                  "journal_checksum, fs mounted w/o journal");
4552                         goto failed_mount_wq;
4553                 }
4554                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4555                         ext4_msg(sb, KERN_ERR, "can't mount with "
4556                                  "journal_async_commit, fs mounted w/o journal");
4557                         goto failed_mount_wq;
4558                 }
4559                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4560                         ext4_msg(sb, KERN_ERR, "can't mount with "
4561                                  "commit=%lu, fs mounted w/o journal",
4562                                  sbi->s_commit_interval / HZ);
4563                         goto failed_mount_wq;
4564                 }
4565                 if (EXT4_MOUNT_DATA_FLAGS &
4566                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4567                         ext4_msg(sb, KERN_ERR, "can't mount with "
4568                                  "data=, fs mounted w/o journal");
4569                         goto failed_mount_wq;
4570                 }
4571                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4572                 clear_opt(sb, JOURNAL_CHECKSUM);
4573                 clear_opt(sb, DATA_FLAGS);
4574                 sbi->s_journal = NULL;
4575                 needs_recovery = 0;
4576                 goto no_journal;
4577         }
4578
4579         if (ext4_has_feature_64bit(sb) &&
4580             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4581                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4582                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4583                 goto failed_mount_wq;
4584         }
4585
4586         if (!set_journal_csum_feature_set(sb)) {
4587                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4588                          "feature set");
4589                 goto failed_mount_wq;
4590         }
4591
4592         /* We have now updated the journal if required, so we can
4593          * validate the data journaling mode. */
4594         switch (test_opt(sb, DATA_FLAGS)) {
4595         case 0:
4596                 /* No mode set, assume a default based on the journal
4597                  * capabilities: ORDERED_DATA if the journal can
4598                  * cope, else JOURNAL_DATA
4599                  */
4600                 if (jbd2_journal_check_available_features
4601                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4602                         set_opt(sb, ORDERED_DATA);
4603                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4604                 } else {
4605                         set_opt(sb, JOURNAL_DATA);
4606                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4607                 }
4608                 break;
4609
4610         case EXT4_MOUNT_ORDERED_DATA:
4611         case EXT4_MOUNT_WRITEBACK_DATA:
4612                 if (!jbd2_journal_check_available_features
4613                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4614                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4615                                "requested data journaling mode");
4616                         goto failed_mount_wq;
4617                 }
4618         default:
4619                 break;
4620         }
4621
4622         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4623             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4624                 ext4_msg(sb, KERN_ERR, "can't mount with "
4625                         "journal_async_commit in data=ordered mode");
4626                 goto failed_mount_wq;
4627         }
4628
4629         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4630
4631         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4632
4633 no_journal:
4634         if (!test_opt(sb, NO_MBCACHE)) {
4635                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4636                 if (!sbi->s_ea_block_cache) {
4637                         ext4_msg(sb, KERN_ERR,
4638                                  "Failed to create ea_block_cache");
4639                         goto failed_mount_wq;
4640                 }
4641
4642                 if (ext4_has_feature_ea_inode(sb)) {
4643                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4644                         if (!sbi->s_ea_inode_cache) {
4645                                 ext4_msg(sb, KERN_ERR,
4646                                          "Failed to create ea_inode_cache");
4647                                 goto failed_mount_wq;
4648                         }
4649                 }
4650         }
4651
4652         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4653                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4654                 goto failed_mount_wq;
4655         }
4656
4657         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4658             !ext4_has_feature_encrypt(sb)) {
4659                 ext4_set_feature_encrypt(sb);
4660                 ext4_commit_super(sb, 1);
4661         }
4662
4663         /*
4664          * Get the # of file system overhead blocks from the
4665          * superblock if present.
4666          */
4667         if (es->s_overhead_clusters)
4668                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4669         else {
4670                 err = ext4_calculate_overhead(sb);
4671                 if (err)
4672                         goto failed_mount_wq;
4673         }
4674
4675         /*
4676          * The maximum number of concurrent works can be high and
4677          * concurrency isn't really necessary.  Limit it to 1.
4678          */
4679         EXT4_SB(sb)->rsv_conversion_wq =
4680                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4681         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4682                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4683                 ret = -ENOMEM;
4684                 goto failed_mount4;
4685         }
4686
4687         /*
4688          * The jbd2_journal_load will have done any necessary log recovery,
4689          * so we can safely mount the rest of the filesystem now.
4690          */
4691
4692         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4693         if (IS_ERR(root)) {
4694                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4695                 ret = PTR_ERR(root);
4696                 root = NULL;
4697                 goto failed_mount4;
4698         }
4699         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4700                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4701                 iput(root);
4702                 goto failed_mount4;
4703         }
4704
4705 #ifdef CONFIG_UNICODE
4706         if (sbi->s_encoding)
4707                 sb->s_d_op = &ext4_dentry_ops;
4708 #endif
4709
4710         sb->s_root = d_make_root(root);
4711         if (!sb->s_root) {
4712                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4713                 ret = -ENOMEM;
4714                 goto failed_mount4;
4715         }
4716
4717         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4718         if (ret == -EROFS) {
4719                 sb->s_flags |= SB_RDONLY;
4720                 ret = 0;
4721         } else if (ret)
4722                 goto failed_mount4a;
4723
4724         ext4_set_resv_clusters(sb);
4725
4726         err = ext4_setup_system_zone(sb);
4727         if (err) {
4728                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4729                          "zone (%d)", err);
4730                 goto failed_mount4a;
4731         }
4732
4733         ext4_ext_init(sb);
4734         err = ext4_mb_init(sb);
4735         if (err) {
4736                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4737                          err);
4738                 goto failed_mount5;
4739         }
4740
4741         block = ext4_count_free_clusters(sb);
4742         ext4_free_blocks_count_set(sbi->s_es,
4743                                    EXT4_C2B(sbi, block));
4744         ext4_superblock_csum_set(sb);
4745         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4746                                   GFP_KERNEL);
4747         if (!err) {
4748                 unsigned long freei = ext4_count_free_inodes(sb);
4749                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4750                 ext4_superblock_csum_set(sb);
4751                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4752                                           GFP_KERNEL);
4753         }
4754         if (!err)
4755                 err = percpu_counter_init(&sbi->s_dirs_counter,
4756                                           ext4_count_dirs(sb), GFP_KERNEL);
4757         if (!err)
4758                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4759                                           GFP_KERNEL);
4760         if (!err)
4761                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
4762
4763         if (err) {
4764                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4765                 goto failed_mount6;
4766         }
4767
4768         if (ext4_has_feature_flex_bg(sb))
4769                 if (!ext4_fill_flex_info(sb)) {
4770                         ext4_msg(sb, KERN_ERR,
4771                                "unable to initialize "
4772                                "flex_bg meta info!");
4773                         goto failed_mount6;
4774                 }
4775
4776         err = ext4_register_li_request(sb, first_not_zeroed);
4777         if (err)
4778                 goto failed_mount6;
4779
4780         err = ext4_register_sysfs(sb);
4781         if (err)
4782                 goto failed_mount7;
4783
4784 #ifdef CONFIG_QUOTA
4785         /* Enable quota usage during mount. */
4786         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4787                 err = ext4_enable_quotas(sb);
4788                 if (err)
4789                         goto failed_mount8;
4790         }
4791 #endif  /* CONFIG_QUOTA */
4792
4793         /*
4794          * Save the original bdev mapping's wb_err value which could be
4795          * used to detect the metadata async write error.
4796          */
4797         spin_lock_init(&sbi->s_bdev_wb_lock);
4798         if (!sb_rdonly(sb))
4799                 errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
4800                                          &sbi->s_bdev_wb_err);
4801         sb->s_bdev->bd_super = sb;
4802         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4803         ext4_orphan_cleanup(sb, es);
4804         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4805         if (needs_recovery) {
4806                 ext4_msg(sb, KERN_INFO, "recovery complete");
4807                 err = ext4_mark_recovery_complete(sb, es);
4808                 if (err)
4809                         goto failed_mount8;
4810         }
4811         if (EXT4_SB(sb)->s_journal) {
4812                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4813                         descr = " journalled data mode";
4814                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4815                         descr = " ordered data mode";
4816                 else
4817                         descr = " writeback data mode";
4818         } else
4819                 descr = "out journal";
4820
4821         if (test_opt(sb, DISCARD)) {
4822                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4823                 if (!blk_queue_discard(q))
4824                         ext4_msg(sb, KERN_WARNING,
4825                                  "mounting with \"discard\" option, but "
4826                                  "the device does not support discard");
4827         }
4828
4829         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4830                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4831                          "Opts: %.*s%s%s", descr,
4832                          (int) sizeof(sbi->s_es->s_mount_opts),
4833                          sbi->s_es->s_mount_opts,
4834                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4835
4836         if (es->s_error_count)
4837                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4838
4839         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4840         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4841         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4842         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4843
4844         kfree(orig_data);
4845         return 0;
4846
4847 cantfind_ext4:
4848         if (!silent)
4849                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4850         goto failed_mount;
4851
4852 failed_mount8:
4853         ext4_unregister_sysfs(sb);
4854 failed_mount7:
4855         ext4_unregister_li_request(sb);
4856 failed_mount6:
4857         ext4_mb_release(sb);
4858         rcu_read_lock();
4859         flex_groups = rcu_dereference(sbi->s_flex_groups);
4860         if (flex_groups) {
4861                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
4862                         kvfree(flex_groups[i]);
4863                 kvfree(flex_groups);
4864         }
4865         rcu_read_unlock();
4866         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4867         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4868         percpu_counter_destroy(&sbi->s_dirs_counter);
4869         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4870         percpu_free_rwsem(&sbi->s_writepages_rwsem);
4871 failed_mount5:
4872         ext4_ext_release(sb);
4873         ext4_release_system_zone(sb);
4874 failed_mount4a:
4875         dput(sb->s_root);
4876         sb->s_root = NULL;
4877 failed_mount4:
4878         ext4_msg(sb, KERN_ERR, "mount failed");
4879         if (EXT4_SB(sb)->rsv_conversion_wq)
4880                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4881 failed_mount_wq:
4882         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4883         sbi->s_ea_inode_cache = NULL;
4884
4885         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4886         sbi->s_ea_block_cache = NULL;
4887
4888         if (sbi->s_journal) {
4889                 jbd2_journal_destroy(sbi->s_journal);
4890                 sbi->s_journal = NULL;
4891         }
4892 failed_mount3a:
4893         ext4_es_unregister_shrinker(sbi);
4894 failed_mount3:
4895         del_timer_sync(&sbi->s_err_report);
4896         if (sbi->s_mmp_tsk)
4897                 kthread_stop(sbi->s_mmp_tsk);
4898 failed_mount2:
4899         rcu_read_lock();
4900         group_desc = rcu_dereference(sbi->s_group_desc);
4901         for (i = 0; i < db_count; i++)
4902                 brelse(group_desc[i]);
4903         kvfree(group_desc);
4904         rcu_read_unlock();
4905 failed_mount:
4906         if (sbi->s_chksum_driver)
4907                 crypto_free_shash(sbi->s_chksum_driver);
4908
4909 #ifdef CONFIG_UNICODE
4910         utf8_unload(sbi->s_encoding);
4911 #endif
4912
4913 #ifdef CONFIG_QUOTA
4914         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4915                 kfree(get_qf_name(sb, sbi, i));
4916 #endif
4917         fscrypt_free_dummy_context(&sbi->s_dummy_enc_ctx);
4918         ext4_blkdev_remove(sbi);
4919         brelse(bh);
4920 out_fail:
4921         sb->s_fs_info = NULL;
4922         kfree(sbi->s_blockgroup_lock);
4923 out_free_base:
4924         kfree(sbi);
4925         kfree(orig_data);
4926         fs_put_dax(dax_dev);
4927         return err ? err : ret;
4928 }
4929
4930 /*
4931  * Setup any per-fs journal parameters now.  We'll do this both on
4932  * initial mount, once the journal has been initialised but before we've
4933  * done any recovery; and again on any subsequent remount.
4934  */
4935 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4936 {
4937         struct ext4_sb_info *sbi = EXT4_SB(sb);
4938
4939         journal->j_commit_interval = sbi->s_commit_interval;
4940         journal->j_min_batch_time = sbi->s_min_batch_time;
4941         journal->j_max_batch_time = sbi->s_max_batch_time;
4942
4943         write_lock(&journal->j_state_lock);
4944         if (test_opt(sb, BARRIER))
4945                 journal->j_flags |= JBD2_BARRIER;
4946         else
4947                 journal->j_flags &= ~JBD2_BARRIER;
4948         if (test_opt(sb, DATA_ERR_ABORT))
4949                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4950         else
4951                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4952         write_unlock(&journal->j_state_lock);
4953 }
4954
4955 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4956                                              unsigned int journal_inum)
4957 {
4958         struct inode *journal_inode;
4959
4960         /*
4961          * Test for the existence of a valid inode on disk.  Bad things
4962          * happen if we iget() an unused inode, as the subsequent iput()
4963          * will try to delete it.
4964          */
4965         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
4966         if (IS_ERR(journal_inode)) {
4967                 ext4_msg(sb, KERN_ERR, "no journal found");
4968                 return NULL;
4969         }
4970         if (!journal_inode->i_nlink) {
4971                 make_bad_inode(journal_inode);
4972                 iput(journal_inode);
4973                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4974                 return NULL;
4975         }
4976
4977         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4978                   journal_inode, journal_inode->i_size);
4979         if (!S_ISREG(journal_inode->i_mode)) {
4980                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4981                 iput(journal_inode);
4982                 return NULL;
4983         }
4984         return journal_inode;
4985 }
4986
4987 static journal_t *ext4_get_journal(struct super_block *sb,
4988                                    unsigned int journal_inum)
4989 {
4990         struct inode *journal_inode;
4991         journal_t *journal;
4992
4993         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
4994                 return NULL;
4995
4996         journal_inode = ext4_get_journal_inode(sb, journal_inum);
4997         if (!journal_inode)
4998                 return NULL;
4999
5000         journal = jbd2_journal_init_inode(journal_inode);
5001         if (!journal) {
5002                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5003                 iput(journal_inode);
5004                 return NULL;
5005         }
5006         journal->j_private = sb;
5007         ext4_init_journal_params(sb, journal);
5008         return journal;
5009 }
5010
5011 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5012                                        dev_t j_dev)
5013 {
5014         struct buffer_head *bh;
5015         journal_t *journal;
5016         ext4_fsblk_t start;
5017         ext4_fsblk_t len;
5018         int hblock, blocksize;
5019         ext4_fsblk_t sb_block;
5020         unsigned long offset;
5021         struct ext4_super_block *es;
5022         struct block_device *bdev;
5023
5024         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5025                 return NULL;
5026
5027         bdev = ext4_blkdev_get(j_dev, sb);
5028         if (bdev == NULL)
5029                 return NULL;
5030
5031         blocksize = sb->s_blocksize;
5032         hblock = bdev_logical_block_size(bdev);
5033         if (blocksize < hblock) {
5034                 ext4_msg(sb, KERN_ERR,
5035                         "blocksize too small for journal device");
5036                 goto out_bdev;
5037         }
5038
5039         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5040         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5041         set_blocksize(bdev, blocksize);
5042         if (!(bh = __bread(bdev, sb_block, blocksize))) {
5043                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5044                        "external journal");
5045                 goto out_bdev;
5046         }
5047
5048         es = (struct ext4_super_block *) (bh->b_data + offset);
5049         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5050             !(le32_to_cpu(es->s_feature_incompat) &
5051               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5052                 ext4_msg(sb, KERN_ERR, "external journal has "
5053                                         "bad superblock");
5054                 brelse(bh);
5055                 goto out_bdev;
5056         }
5057
5058         if ((le32_to_cpu(es->s_feature_ro_compat) &
5059              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5060             es->s_checksum != ext4_superblock_csum(sb, es)) {
5061                 ext4_msg(sb, KERN_ERR, "external journal has "
5062                                        "corrupt superblock");
5063                 brelse(bh);
5064                 goto out_bdev;
5065         }
5066
5067         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5068                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5069                 brelse(bh);
5070                 goto out_bdev;
5071         }
5072
5073         len = ext4_blocks_count(es);
5074         start = sb_block + 1;
5075         brelse(bh);     /* we're done with the superblock */
5076
5077         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5078                                         start, len, blocksize);
5079         if (!journal) {
5080                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5081                 goto out_bdev;
5082         }
5083         journal->j_private = sb;
5084         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
5085         wait_on_buffer(journal->j_sb_buffer);
5086         if (!buffer_uptodate(journal->j_sb_buffer)) {
5087                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5088                 goto out_journal;
5089         }
5090         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5091                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5092                                         "user (unsupported) - %d",
5093                         be32_to_cpu(journal->j_superblock->s_nr_users));
5094                 goto out_journal;
5095         }
5096         EXT4_SB(sb)->journal_bdev = bdev;
5097         ext4_init_journal_params(sb, journal);
5098         return journal;
5099
5100 out_journal:
5101         jbd2_journal_destroy(journal);
5102 out_bdev:
5103         ext4_blkdev_put(bdev);
5104         return NULL;
5105 }
5106
5107 static int ext4_load_journal(struct super_block *sb,
5108                              struct ext4_super_block *es,
5109                              unsigned long journal_devnum)
5110 {
5111         journal_t *journal;
5112         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5113         dev_t journal_dev;
5114         int err = 0;
5115         int really_read_only;
5116         int journal_dev_ro;
5117
5118         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5119                 return -EFSCORRUPTED;
5120
5121         if (journal_devnum &&
5122             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5123                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5124                         "numbers have changed");
5125                 journal_dev = new_decode_dev(journal_devnum);
5126         } else
5127                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5128
5129         if (journal_inum && journal_dev) {
5130                 ext4_msg(sb, KERN_ERR,
5131                          "filesystem has both journal inode and journal device!");
5132                 return -EINVAL;
5133         }
5134
5135         if (journal_inum) {
5136                 journal = ext4_get_journal(sb, journal_inum);
5137                 if (!journal)
5138                         return -EINVAL;
5139         } else {
5140                 journal = ext4_get_dev_journal(sb, journal_dev);
5141                 if (!journal)
5142                         return -EINVAL;
5143         }
5144
5145         journal_dev_ro = bdev_read_only(journal->j_dev);
5146         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5147
5148         if (journal_dev_ro && !sb_rdonly(sb)) {
5149                 ext4_msg(sb, KERN_ERR,
5150                          "journal device read-only, try mounting with '-o ro'");
5151                 err = -EROFS;
5152                 goto err_out;
5153         }
5154
5155         /*
5156          * Are we loading a blank journal or performing recovery after a
5157          * crash?  For recovery, we need to check in advance whether we
5158          * can get read-write access to the device.
5159          */
5160         if (ext4_has_feature_journal_needs_recovery(sb)) {
5161                 if (sb_rdonly(sb)) {
5162                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5163                                         "required on readonly filesystem");
5164                         if (really_read_only) {
5165                                 ext4_msg(sb, KERN_ERR, "write access "
5166                                         "unavailable, cannot proceed "
5167                                         "(try mounting with noload)");
5168                                 err = -EROFS;
5169                                 goto err_out;
5170                         }
5171                         ext4_msg(sb, KERN_INFO, "write access will "
5172                                "be enabled during recovery");
5173                 }
5174         }
5175
5176         if (!(journal->j_flags & JBD2_BARRIER))
5177                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5178
5179         if (!ext4_has_feature_journal_needs_recovery(sb))
5180                 err = jbd2_journal_wipe(journal, !really_read_only);
5181         if (!err) {
5182                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5183                 if (save)
5184                         memcpy(save, ((char *) es) +
5185                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5186                 err = jbd2_journal_load(journal);
5187                 if (save)
5188                         memcpy(((char *) es) + EXT4_S_ERR_START,
5189                                save, EXT4_S_ERR_LEN);
5190                 kfree(save);
5191         }
5192
5193         if (err) {
5194                 ext4_msg(sb, KERN_ERR, "error loading journal");
5195                 goto err_out;
5196         }
5197
5198         EXT4_SB(sb)->s_journal = journal;
5199         err = ext4_clear_journal_err(sb, es);
5200         if (err) {
5201                 EXT4_SB(sb)->s_journal = NULL;
5202                 jbd2_journal_destroy(journal);
5203                 return err;
5204         }
5205
5206         if (!really_read_only && journal_devnum &&
5207             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5208                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5209
5210                 /* Make sure we flush the recovery flag to disk. */
5211                 ext4_commit_super(sb, 1);
5212         }
5213
5214         return 0;
5215
5216 err_out:
5217         jbd2_journal_destroy(journal);
5218         return err;
5219 }
5220
5221 static int ext4_commit_super(struct super_block *sb, int sync)
5222 {
5223         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
5224         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5225         int error = 0;
5226
5227         if (!sbh || block_device_ejected(sb))
5228                 return error;
5229
5230         /*
5231          * The superblock bh should be mapped, but it might not be if the
5232          * device was hot-removed. Not much we can do but fail the I/O.
5233          */
5234         if (!buffer_mapped(sbh))
5235                 return error;
5236
5237         /*
5238          * If the file system is mounted read-only, don't update the
5239          * superblock write time.  This avoids updating the superblock
5240          * write time when we are mounting the root file system
5241          * read/only but we need to replay the journal; at that point,
5242          * for people who are east of GMT and who make their clock
5243          * tick in localtime for Windows bug-for-bug compatibility,
5244          * the clock is set in the future, and this will cause e2fsck
5245          * to complain and force a full file system check.
5246          */
5247         if (!(sb->s_flags & SB_RDONLY))
5248                 ext4_update_tstamp(es, s_wtime);
5249         if (sb->s_bdev->bd_part)
5250                 es->s_kbytes_written =
5251                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5252                             ((part_stat_read(sb->s_bdev->bd_part,
5253                                              sectors[STAT_WRITE]) -
5254                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
5255         else
5256                 es->s_kbytes_written =
5257                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5258         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5259                 ext4_free_blocks_count_set(es,
5260                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5261                                 &EXT4_SB(sb)->s_freeclusters_counter)));
5262         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5263                 es->s_free_inodes_count =
5264                         cpu_to_le32(percpu_counter_sum_positive(
5265                                 &EXT4_SB(sb)->s_freeinodes_counter));
5266         BUFFER_TRACE(sbh, "marking dirty");
5267         ext4_superblock_csum_set(sb);
5268         if (sync)
5269                 lock_buffer(sbh);
5270         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5271                 /*
5272                  * Oh, dear.  A previous attempt to write the
5273                  * superblock failed.  This could happen because the
5274                  * USB device was yanked out.  Or it could happen to
5275                  * be a transient write error and maybe the block will
5276                  * be remapped.  Nothing we can do but to retry the
5277                  * write and hope for the best.
5278                  */
5279                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5280                        "superblock detected");
5281                 clear_buffer_write_io_error(sbh);
5282                 set_buffer_uptodate(sbh);
5283         }
5284         mark_buffer_dirty(sbh);
5285         if (sync) {
5286                 unlock_buffer(sbh);
5287                 error = __sync_dirty_buffer(sbh,
5288                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5289                 if (buffer_write_io_error(sbh)) {
5290                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5291                                "superblock");
5292                         clear_buffer_write_io_error(sbh);
5293                         set_buffer_uptodate(sbh);
5294                 }
5295         }
5296         return error;
5297 }
5298
5299 /*
5300  * Have we just finished recovery?  If so, and if we are mounting (or
5301  * remounting) the filesystem readonly, then we will end up with a
5302  * consistent fs on disk.  Record that fact.
5303  */
5304 static int ext4_mark_recovery_complete(struct super_block *sb,
5305                                        struct ext4_super_block *es)
5306 {
5307         int err;
5308         journal_t *journal = EXT4_SB(sb)->s_journal;
5309
5310         if (!ext4_has_feature_journal(sb)) {
5311                 if (journal != NULL) {
5312                         ext4_error(sb, "Journal got removed while the fs was "
5313                                    "mounted!");
5314                         return -EFSCORRUPTED;
5315                 }
5316                 return 0;
5317         }
5318         jbd2_journal_lock_updates(journal);
5319         err = jbd2_journal_flush(journal);
5320         if (err < 0)
5321                 goto out;
5322
5323         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5324                 ext4_clear_feature_journal_needs_recovery(sb);
5325                 ext4_commit_super(sb, 1);
5326         }
5327 out:
5328         jbd2_journal_unlock_updates(journal);
5329         return err;
5330 }
5331
5332 /*
5333  * If we are mounting (or read-write remounting) a filesystem whose journal
5334  * has recorded an error from a previous lifetime, move that error to the
5335  * main filesystem now.
5336  */
5337 static int ext4_clear_journal_err(struct super_block *sb,
5338                                    struct ext4_super_block *es)
5339 {
5340         journal_t *journal;
5341         int j_errno;
5342         const char *errstr;
5343
5344         if (!ext4_has_feature_journal(sb)) {
5345                 ext4_error(sb, "Journal got removed while the fs was mounted!");
5346                 return -EFSCORRUPTED;
5347         }
5348
5349         journal = EXT4_SB(sb)->s_journal;
5350
5351         /*
5352          * Now check for any error status which may have been recorded in the
5353          * journal by a prior ext4_error() or ext4_abort()
5354          */
5355
5356         j_errno = jbd2_journal_errno(journal);
5357         if (j_errno) {
5358                 char nbuf[16];
5359
5360                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5361                 ext4_warning(sb, "Filesystem error recorded "
5362                              "from previous mount: %s", errstr);
5363                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5364
5365                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5366                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5367                 ext4_commit_super(sb, 1);
5368
5369                 jbd2_journal_clear_err(journal);
5370                 jbd2_journal_update_sb_errno(journal);
5371         }
5372         return 0;
5373 }
5374
5375 /*
5376  * Force the running and committing transactions to commit,
5377  * and wait on the commit.
5378  */
5379 int ext4_force_commit(struct super_block *sb)
5380 {
5381         journal_t *journal;
5382
5383         if (sb_rdonly(sb))
5384                 return 0;
5385
5386         journal = EXT4_SB(sb)->s_journal;
5387         return ext4_journal_force_commit(journal);
5388 }
5389
5390 static int ext4_sync_fs(struct super_block *sb, int wait)
5391 {
5392         int ret = 0;
5393         tid_t target;
5394         bool needs_barrier = false;
5395         struct ext4_sb_info *sbi = EXT4_SB(sb);
5396
5397         if (unlikely(ext4_forced_shutdown(sbi)))
5398                 return 0;
5399
5400         trace_ext4_sync_fs(sb, wait);
5401         flush_workqueue(sbi->rsv_conversion_wq);
5402         /*
5403          * Writeback quota in non-journalled quota case - journalled quota has
5404          * no dirty dquots
5405          */
5406         dquot_writeback_dquots(sb, -1);
5407         /*
5408          * Data writeback is possible w/o journal transaction, so barrier must
5409          * being sent at the end of the function. But we can skip it if
5410          * transaction_commit will do it for us.
5411          */
5412         if (sbi->s_journal) {
5413                 target = jbd2_get_latest_transaction(sbi->s_journal);
5414                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5415                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5416                         needs_barrier = true;
5417
5418                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5419                         if (wait)
5420                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5421                                                            target);
5422                 }
5423         } else if (wait && test_opt(sb, BARRIER))
5424                 needs_barrier = true;
5425         if (needs_barrier) {
5426                 int err;
5427                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL);
5428                 if (!ret)
5429                         ret = err;
5430         }
5431
5432         return ret;
5433 }
5434
5435 /*
5436  * LVM calls this function before a (read-only) snapshot is created.  This
5437  * gives us a chance to flush the journal completely and mark the fs clean.
5438  *
5439  * Note that only this function cannot bring a filesystem to be in a clean
5440  * state independently. It relies on upper layer to stop all data & metadata
5441  * modifications.
5442  */
5443 static int ext4_freeze(struct super_block *sb)
5444 {
5445         int error = 0;
5446         journal_t *journal;
5447
5448         if (sb_rdonly(sb))
5449                 return 0;
5450
5451         journal = EXT4_SB(sb)->s_journal;
5452
5453         if (journal) {
5454                 /* Now we set up the journal barrier. */
5455                 jbd2_journal_lock_updates(journal);
5456
5457                 /*
5458                  * Don't clear the needs_recovery flag if we failed to
5459                  * flush the journal.
5460                  */
5461                 error = jbd2_journal_flush(journal);
5462                 if (error < 0)
5463                         goto out;
5464
5465                 /* Journal blocked and flushed, clear needs_recovery flag. */
5466                 ext4_clear_feature_journal_needs_recovery(sb);
5467         }
5468
5469         error = ext4_commit_super(sb, 1);
5470 out:
5471         if (journal)
5472                 /* we rely on upper layer to stop further updates */
5473                 jbd2_journal_unlock_updates(journal);
5474         return error;
5475 }
5476
5477 /*
5478  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5479  * flag here, even though the filesystem is not technically dirty yet.
5480  */
5481 static int ext4_unfreeze(struct super_block *sb)
5482 {
5483         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5484                 return 0;
5485
5486         if (EXT4_SB(sb)->s_journal) {
5487                 /* Reset the needs_recovery flag before the fs is unlocked. */
5488                 ext4_set_feature_journal_needs_recovery(sb);
5489         }
5490
5491         ext4_commit_super(sb, 1);
5492         return 0;
5493 }
5494
5495 /*
5496  * Structure to save mount options for ext4_remount's benefit
5497  */
5498 struct ext4_mount_options {
5499         unsigned long s_mount_opt;
5500         unsigned long s_mount_opt2;
5501         kuid_t s_resuid;
5502         kgid_t s_resgid;
5503         unsigned long s_commit_interval;
5504         u32 s_min_batch_time, s_max_batch_time;
5505 #ifdef CONFIG_QUOTA
5506         int s_jquota_fmt;
5507         char *s_qf_names[EXT4_MAXQUOTAS];
5508 #endif
5509 };
5510
5511 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5512 {
5513         struct ext4_super_block *es;
5514         struct ext4_sb_info *sbi = EXT4_SB(sb);
5515         unsigned long old_sb_flags;
5516         struct ext4_mount_options old_opts;
5517         int enable_quota = 0;
5518         ext4_group_t g;
5519         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5520         int err = 0;
5521 #ifdef CONFIG_QUOTA
5522         int i, j;
5523         char *to_free[EXT4_MAXQUOTAS];
5524 #endif
5525         char *orig_data = kstrdup(data, GFP_KERNEL);
5526
5527         if (data && !orig_data)
5528                 return -ENOMEM;
5529
5530         /* Store the original options */
5531         old_sb_flags = sb->s_flags;
5532         old_opts.s_mount_opt = sbi->s_mount_opt;
5533         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5534         old_opts.s_resuid = sbi->s_resuid;
5535         old_opts.s_resgid = sbi->s_resgid;
5536         old_opts.s_commit_interval = sbi->s_commit_interval;
5537         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5538         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5539 #ifdef CONFIG_QUOTA
5540         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5541         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5542                 if (sbi->s_qf_names[i]) {
5543                         char *qf_name = get_qf_name(sb, sbi, i);
5544
5545                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5546                         if (!old_opts.s_qf_names[i]) {
5547                                 for (j = 0; j < i; j++)
5548                                         kfree(old_opts.s_qf_names[j]);
5549                                 kfree(orig_data);
5550                                 return -ENOMEM;
5551                         }
5552                 } else
5553                         old_opts.s_qf_names[i] = NULL;
5554 #endif
5555         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5556                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5557
5558         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5559                 err = -EINVAL;
5560                 goto restore_opts;
5561         }
5562
5563         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5564             test_opt(sb, JOURNAL_CHECKSUM)) {
5565                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5566                          "during remount not supported; ignoring");
5567                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5568         }
5569
5570         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5571                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5572                         ext4_msg(sb, KERN_ERR, "can't mount with "
5573                                  "both data=journal and delalloc");
5574                         err = -EINVAL;
5575                         goto restore_opts;
5576                 }
5577                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5578                         ext4_msg(sb, KERN_ERR, "can't mount with "
5579                                  "both data=journal and dioread_nolock");
5580                         err = -EINVAL;
5581                         goto restore_opts;
5582                 }
5583         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5584                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5585                         ext4_msg(sb, KERN_ERR, "can't mount with "
5586                                 "journal_async_commit in data=ordered mode");
5587                         err = -EINVAL;
5588                         goto restore_opts;
5589                 }
5590         }
5591
5592         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5593                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5594                 err = -EINVAL;
5595                 goto restore_opts;
5596         }
5597
5598         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5599                 ext4_abort(sb, EXT4_ERR_ESHUTDOWN, "Abort forced by user");
5600
5601         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5602                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5603
5604         es = sbi->s_es;
5605
5606         if (sbi->s_journal) {
5607                 ext4_init_journal_params(sb, sbi->s_journal);
5608                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5609         }
5610
5611         if (*flags & SB_LAZYTIME)
5612                 sb->s_flags |= SB_LAZYTIME;
5613
5614         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5615                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5616                         err = -EROFS;
5617                         goto restore_opts;
5618                 }
5619
5620                 if (*flags & SB_RDONLY) {
5621                         err = sync_filesystem(sb);
5622                         if (err < 0)
5623                                 goto restore_opts;
5624                         err = dquot_suspend(sb, -1);
5625                         if (err < 0)
5626                                 goto restore_opts;
5627
5628                         /*
5629                          * First of all, the unconditional stuff we have to do
5630                          * to disable replay of the journal when we next remount
5631                          */
5632                         sb->s_flags |= SB_RDONLY;
5633
5634                         /*
5635                          * OK, test if we are remounting a valid rw partition
5636                          * readonly, and if so set the rdonly flag and then
5637                          * mark the partition as valid again.
5638                          */
5639                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5640                             (sbi->s_mount_state & EXT4_VALID_FS))
5641                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5642
5643                         if (sbi->s_journal) {
5644                                 /*
5645                                  * We let remount-ro finish even if marking fs
5646                                  * as clean failed...
5647                                  */
5648                                 ext4_mark_recovery_complete(sb, es);
5649                         }
5650                         if (sbi->s_mmp_tsk)
5651                                 kthread_stop(sbi->s_mmp_tsk);
5652                 } else {
5653                         /* Make sure we can mount this feature set readwrite */
5654                         if (ext4_has_feature_readonly(sb) ||
5655                             !ext4_feature_set_ok(sb, 0)) {
5656                                 err = -EROFS;
5657                                 goto restore_opts;
5658                         }
5659                         /*
5660                          * Make sure the group descriptor checksums
5661                          * are sane.  If they aren't, refuse to remount r/w.
5662                          */
5663                         for (g = 0; g < sbi->s_groups_count; g++) {
5664                                 struct ext4_group_desc *gdp =
5665                                         ext4_get_group_desc(sb, g, NULL);
5666
5667                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5668                                         ext4_msg(sb, KERN_ERR,
5669                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5670                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5671                                                le16_to_cpu(gdp->bg_checksum));
5672                                         err = -EFSBADCRC;
5673                                         goto restore_opts;
5674                                 }
5675                         }
5676
5677                         /*
5678                          * If we have an unprocessed orphan list hanging
5679                          * around from a previously readonly bdev mount,
5680                          * require a full umount/remount for now.
5681                          */
5682                         if (es->s_last_orphan) {
5683                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5684                                        "remount RDWR because of unprocessed "
5685                                        "orphan inode list.  Please "
5686                                        "umount/remount instead");
5687                                 err = -EINVAL;
5688                                 goto restore_opts;
5689                         }
5690
5691                         /*
5692                          * Update the original bdev mapping's wb_err value
5693                          * which could be used to detect the metadata async
5694                          * write error.
5695                          */
5696                         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5697                                                  &sbi->s_bdev_wb_err);
5698
5699                         /*
5700                          * Mounting a RDONLY partition read-write, so reread
5701                          * and store the current valid flag.  (It may have
5702                          * been changed by e2fsck since we originally mounted
5703                          * the partition.)
5704                          */
5705                         if (sbi->s_journal) {
5706                                 err = ext4_clear_journal_err(sb, es);
5707                                 if (err)
5708                                         goto restore_opts;
5709                         }
5710                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5711
5712                         err = ext4_setup_super(sb, es, 0);
5713                         if (err)
5714                                 goto restore_opts;
5715
5716                         sb->s_flags &= ~SB_RDONLY;
5717                         if (ext4_has_feature_mmp(sb))
5718                                 if (ext4_multi_mount_protect(sb,
5719                                                 le64_to_cpu(es->s_mmp_block))) {
5720                                         err = -EROFS;
5721                                         goto restore_opts;
5722                                 }
5723                         enable_quota = 1;
5724                 }
5725         }
5726
5727         /*
5728          * Reinitialize lazy itable initialization thread based on
5729          * current settings
5730          */
5731         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5732                 ext4_unregister_li_request(sb);
5733         else {
5734                 ext4_group_t first_not_zeroed;
5735                 first_not_zeroed = ext4_has_uninit_itable(sb);
5736                 ext4_register_li_request(sb, first_not_zeroed);
5737         }
5738
5739         ext4_setup_system_zone(sb);
5740         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5741                 err = ext4_commit_super(sb, 1);
5742                 if (err)
5743                         goto restore_opts;
5744         }
5745
5746 #ifdef CONFIG_QUOTA
5747         /* Release old quota file names */
5748         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5749                 kfree(old_opts.s_qf_names[i]);
5750         if (enable_quota) {
5751                 if (sb_any_quota_suspended(sb))
5752                         dquot_resume(sb, -1);
5753                 else if (ext4_has_feature_quota(sb)) {
5754                         err = ext4_enable_quotas(sb);
5755                         if (err)
5756                                 goto restore_opts;
5757                 }
5758         }
5759 #endif
5760
5761         *flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME);
5762         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5763         kfree(orig_data);
5764         return 0;
5765
5766 restore_opts:
5767         sb->s_flags = old_sb_flags;
5768         sbi->s_mount_opt = old_opts.s_mount_opt;
5769         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5770         sbi->s_resuid = old_opts.s_resuid;
5771         sbi->s_resgid = old_opts.s_resgid;
5772         sbi->s_commit_interval = old_opts.s_commit_interval;
5773         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5774         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5775 #ifdef CONFIG_QUOTA
5776         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5777         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5778                 to_free[i] = get_qf_name(sb, sbi, i);
5779                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
5780         }
5781         synchronize_rcu();
5782         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5783                 kfree(to_free[i]);
5784 #endif
5785         kfree(orig_data);
5786         return err;
5787 }
5788
5789 #ifdef CONFIG_QUOTA
5790 static int ext4_statfs_project(struct super_block *sb,
5791                                kprojid_t projid, struct kstatfs *buf)
5792 {
5793         struct kqid qid;
5794         struct dquot *dquot;
5795         u64 limit;
5796         u64 curblock;
5797
5798         qid = make_kqid_projid(projid);
5799         dquot = dqget(sb, qid);
5800         if (IS_ERR(dquot))
5801                 return PTR_ERR(dquot);
5802         spin_lock(&dquot->dq_dqb_lock);
5803
5804         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
5805                              dquot->dq_dqb.dqb_bhardlimit);
5806         limit >>= sb->s_blocksize_bits;
5807
5808         if (limit && buf->f_blocks > limit) {
5809                 curblock = (dquot->dq_dqb.dqb_curspace +
5810                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5811                 buf->f_blocks = limit;
5812                 buf->f_bfree = buf->f_bavail =
5813                         (buf->f_blocks > curblock) ?
5814                          (buf->f_blocks - curblock) : 0;
5815         }
5816
5817         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
5818                              dquot->dq_dqb.dqb_ihardlimit);
5819         if (limit && buf->f_files > limit) {
5820                 buf->f_files = limit;
5821                 buf->f_ffree =
5822                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5823                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5824         }
5825
5826         spin_unlock(&dquot->dq_dqb_lock);
5827         dqput(dquot);
5828         return 0;
5829 }
5830 #endif
5831
5832 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5833 {
5834         struct super_block *sb = dentry->d_sb;
5835         struct ext4_sb_info *sbi = EXT4_SB(sb);
5836         struct ext4_super_block *es = sbi->s_es;
5837         ext4_fsblk_t overhead = 0, resv_blocks;
5838         u64 fsid;
5839         s64 bfree;
5840         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5841
5842         if (!test_opt(sb, MINIX_DF))
5843                 overhead = sbi->s_overhead;
5844
5845         buf->f_type = EXT4_SUPER_MAGIC;
5846         buf->f_bsize = sb->s_blocksize;
5847         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5848         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5849                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5850         /* prevent underflow in case that few free space is available */
5851         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5852         buf->f_bavail = buf->f_bfree -
5853                         (ext4_r_blocks_count(es) + resv_blocks);
5854         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5855                 buf->f_bavail = 0;
5856         buf->f_files = le32_to_cpu(es->s_inodes_count);
5857         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5858         buf->f_namelen = EXT4_NAME_LEN;
5859         fsid = le64_to_cpup((void *)es->s_uuid) ^
5860                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5861         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5862         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5863
5864 #ifdef CONFIG_QUOTA
5865         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5866             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5867                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5868 #endif
5869         return 0;
5870 }
5871
5872
5873 #ifdef CONFIG_QUOTA
5874
5875 /*
5876  * Helper functions so that transaction is started before we acquire dqio_sem
5877  * to keep correct lock ordering of transaction > dqio_sem
5878  */
5879 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5880 {
5881         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5882 }
5883
5884 static int ext4_write_dquot(struct dquot *dquot)
5885 {
5886         int ret, err;
5887         handle_t *handle;
5888         struct inode *inode;
5889
5890         inode = dquot_to_inode(dquot);
5891         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5892                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5893         if (IS_ERR(handle))
5894                 return PTR_ERR(handle);
5895         ret = dquot_commit(dquot);
5896         err = ext4_journal_stop(handle);
5897         if (!ret)
5898                 ret = err;
5899         return ret;
5900 }
5901
5902 static int ext4_acquire_dquot(struct dquot *dquot)
5903 {
5904         int ret, err;
5905         handle_t *handle;
5906
5907         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5908                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5909         if (IS_ERR(handle))
5910                 return PTR_ERR(handle);
5911         ret = dquot_acquire(dquot);
5912         err = ext4_journal_stop(handle);
5913         if (!ret)
5914                 ret = err;
5915         return ret;
5916 }
5917
5918 static int ext4_release_dquot(struct dquot *dquot)
5919 {
5920         int ret, err;
5921         handle_t *handle;
5922
5923         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5924                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5925         if (IS_ERR(handle)) {
5926                 /* Release dquot anyway to avoid endless cycle in dqput() */
5927                 dquot_release(dquot);
5928                 return PTR_ERR(handle);
5929         }
5930         ret = dquot_release(dquot);
5931         err = ext4_journal_stop(handle);
5932         if (!ret)
5933                 ret = err;
5934         return ret;
5935 }
5936
5937 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5938 {
5939         struct super_block *sb = dquot->dq_sb;
5940         struct ext4_sb_info *sbi = EXT4_SB(sb);
5941
5942         /* Are we journaling quotas? */
5943         if (ext4_has_feature_quota(sb) ||
5944             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5945                 dquot_mark_dquot_dirty(dquot);
5946                 return ext4_write_dquot(dquot);
5947         } else {
5948                 return dquot_mark_dquot_dirty(dquot);
5949         }
5950 }
5951
5952 static int ext4_write_info(struct super_block *sb, int type)
5953 {
5954         int ret, err;
5955         handle_t *handle;
5956
5957         /* Data block + inode block */
5958         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5959         if (IS_ERR(handle))
5960                 return PTR_ERR(handle);
5961         ret = dquot_commit_info(sb, type);
5962         err = ext4_journal_stop(handle);
5963         if (!ret)
5964                 ret = err;
5965         return ret;
5966 }
5967
5968 /*
5969  * Turn on quotas during mount time - we need to find
5970  * the quota file and such...
5971  */
5972 static int ext4_quota_on_mount(struct super_block *sb, int type)
5973 {
5974         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
5975                                         EXT4_SB(sb)->s_jquota_fmt, type);
5976 }
5977
5978 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5979 {
5980         struct ext4_inode_info *ei = EXT4_I(inode);
5981
5982         /* The first argument of lockdep_set_subclass has to be
5983          * *exactly* the same as the argument to init_rwsem() --- in
5984          * this case, in init_once() --- or lockdep gets unhappy
5985          * because the name of the lock is set using the
5986          * stringification of the argument to init_rwsem().
5987          */
5988         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
5989         lockdep_set_subclass(&ei->i_data_sem, subclass);
5990 }
5991
5992 /*
5993  * Standard function to be called on quota_on
5994  */
5995 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5996                          const struct path *path)
5997 {
5998         int err;
5999
6000         if (!test_opt(sb, QUOTA))
6001                 return -EINVAL;
6002
6003         /* Quotafile not on the same filesystem? */
6004         if (path->dentry->d_sb != sb)
6005                 return -EXDEV;
6006         /* Journaling quota? */
6007         if (EXT4_SB(sb)->s_qf_names[type]) {
6008                 /* Quotafile not in fs root? */
6009                 if (path->dentry->d_parent != sb->s_root)
6010                         ext4_msg(sb, KERN_WARNING,
6011                                 "Quota file not on filesystem root. "
6012                                 "Journaled quota will not work");
6013                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6014         } else {
6015                 /*
6016                  * Clear the flag just in case mount options changed since
6017                  * last time.
6018                  */
6019                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6020         }
6021
6022         /*
6023          * When we journal data on quota file, we have to flush journal to see
6024          * all updates to the file when we bypass pagecache...
6025          */
6026         if (EXT4_SB(sb)->s_journal &&
6027             ext4_should_journal_data(d_inode(path->dentry))) {
6028                 /*
6029                  * We don't need to lock updates but journal_flush() could
6030                  * otherwise be livelocked...
6031                  */
6032                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6033                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
6034                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6035                 if (err)
6036                         return err;
6037         }
6038
6039         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6040         err = dquot_quota_on(sb, type, format_id, path);
6041         if (err) {
6042                 lockdep_set_quota_inode(path->dentry->d_inode,
6043                                              I_DATA_SEM_NORMAL);
6044         } else {
6045                 struct inode *inode = d_inode(path->dentry);
6046                 handle_t *handle;
6047
6048                 /*
6049                  * Set inode flags to prevent userspace from messing with quota
6050                  * files. If this fails, we return success anyway since quotas
6051                  * are already enabled and this is not a hard failure.
6052                  */
6053                 inode_lock(inode);
6054                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6055                 if (IS_ERR(handle))
6056                         goto unlock_inode;
6057                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6058                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6059                                 S_NOATIME | S_IMMUTABLE);
6060                 err = ext4_mark_inode_dirty(handle, inode);
6061                 ext4_journal_stop(handle);
6062         unlock_inode:
6063                 inode_unlock(inode);
6064         }
6065         return err;
6066 }
6067
6068 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6069                              unsigned int flags)
6070 {
6071         int err;
6072         struct inode *qf_inode;
6073         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6074                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6075                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6076                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6077         };
6078
6079         BUG_ON(!ext4_has_feature_quota(sb));
6080
6081         if (!qf_inums[type])
6082                 return -EPERM;
6083
6084         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6085         if (IS_ERR(qf_inode)) {
6086                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6087                 return PTR_ERR(qf_inode);
6088         }
6089
6090         /* Don't account quota for quota files to avoid recursion */
6091         qf_inode->i_flags |= S_NOQUOTA;
6092         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6093         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6094         if (err)
6095                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6096         iput(qf_inode);
6097
6098         return err;
6099 }
6100
6101 /* Enable usage tracking for all quota types. */
6102 static int ext4_enable_quotas(struct super_block *sb)
6103 {
6104         int type, err = 0;
6105         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6106                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6107                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6108                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6109         };
6110         bool quota_mopt[EXT4_MAXQUOTAS] = {
6111                 test_opt(sb, USRQUOTA),
6112                 test_opt(sb, GRPQUOTA),
6113                 test_opt(sb, PRJQUOTA),
6114         };
6115
6116         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6117         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6118                 if (qf_inums[type]) {
6119                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6120                                 DQUOT_USAGE_ENABLED |
6121                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6122                         if (err) {
6123                                 ext4_warning(sb,
6124                                         "Failed to enable quota tracking "
6125                                         "(type=%d, err=%d). Please run "
6126                                         "e2fsck to fix.", type, err);
6127                                 for (type--; type >= 0; type--)
6128                                         dquot_quota_off(sb, type);
6129
6130                                 return err;
6131                         }
6132                 }
6133         }
6134         return 0;
6135 }
6136
6137 static int ext4_quota_off(struct super_block *sb, int type)
6138 {
6139         struct inode *inode = sb_dqopt(sb)->files[type];
6140         handle_t *handle;
6141         int err;
6142
6143         /* Force all delayed allocation blocks to be allocated.
6144          * Caller already holds s_umount sem */
6145         if (test_opt(sb, DELALLOC))
6146                 sync_filesystem(sb);
6147
6148         if (!inode || !igrab(inode))
6149                 goto out;
6150
6151         err = dquot_quota_off(sb, type);
6152         if (err || ext4_has_feature_quota(sb))
6153                 goto out_put;
6154
6155         inode_lock(inode);
6156         /*
6157          * Update modification times of quota files when userspace can
6158          * start looking at them. If we fail, we return success anyway since
6159          * this is not a hard failure and quotas are already disabled.
6160          */
6161         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6162         if (IS_ERR(handle)) {
6163                 err = PTR_ERR(handle);
6164                 goto out_unlock;
6165         }
6166         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6167         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6168         inode->i_mtime = inode->i_ctime = current_time(inode);
6169         err = ext4_mark_inode_dirty(handle, inode);
6170         ext4_journal_stop(handle);
6171 out_unlock:
6172         inode_unlock(inode);
6173 out_put:
6174         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6175         iput(inode);
6176         return err;
6177 out:
6178         return dquot_quota_off(sb, type);
6179 }
6180
6181 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6182  * acquiring the locks... As quota files are never truncated and quota code
6183  * itself serializes the operations (and no one else should touch the files)
6184  * we don't have to be afraid of races */
6185 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6186                                size_t len, loff_t off)
6187 {
6188         struct inode *inode = sb_dqopt(sb)->files[type];
6189         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6190         int offset = off & (sb->s_blocksize - 1);
6191         int tocopy;
6192         size_t toread;
6193         struct buffer_head *bh;
6194         loff_t i_size = i_size_read(inode);
6195
6196         if (off > i_size)
6197                 return 0;
6198         if (off+len > i_size)
6199                 len = i_size-off;
6200         toread = len;
6201         while (toread > 0) {
6202                 tocopy = sb->s_blocksize - offset < toread ?
6203                                 sb->s_blocksize - offset : toread;
6204                 bh = ext4_bread(NULL, inode, blk, 0);
6205                 if (IS_ERR(bh))
6206                         return PTR_ERR(bh);
6207                 if (!bh)        /* A hole? */
6208                         memset(data, 0, tocopy);
6209                 else
6210                         memcpy(data, bh->b_data+offset, tocopy);
6211                 brelse(bh);
6212                 offset = 0;
6213                 toread -= tocopy;
6214                 data += tocopy;
6215                 blk++;
6216         }
6217         return len;
6218 }
6219
6220 /* Write to quotafile (we know the transaction is already started and has
6221  * enough credits) */
6222 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6223                                 const char *data, size_t len, loff_t off)
6224 {
6225         struct inode *inode = sb_dqopt(sb)->files[type];
6226         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6227         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6228         int retries = 0;
6229         struct buffer_head *bh;
6230         handle_t *handle = journal_current_handle();
6231
6232         if (EXT4_SB(sb)->s_journal && !handle) {
6233                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6234                         " cancelled because transaction is not started",
6235                         (unsigned long long)off, (unsigned long long)len);
6236                 return -EIO;
6237         }
6238         /*
6239          * Since we account only one data block in transaction credits,
6240          * then it is impossible to cross a block boundary.
6241          */
6242         if (sb->s_blocksize - offset < len) {
6243                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6244                         " cancelled because not block aligned",
6245                         (unsigned long long)off, (unsigned long long)len);
6246                 return -EIO;
6247         }
6248
6249         do {
6250                 bh = ext4_bread(handle, inode, blk,
6251                                 EXT4_GET_BLOCKS_CREATE |
6252                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6253         } while (PTR_ERR(bh) == -ENOSPC &&
6254                  ext4_should_retry_alloc(inode->i_sb, &retries));
6255         if (IS_ERR(bh))
6256                 return PTR_ERR(bh);
6257         if (!bh)
6258                 goto out;
6259         BUFFER_TRACE(bh, "get write access");
6260         err = ext4_journal_get_write_access(handle, bh);
6261         if (err) {
6262                 brelse(bh);
6263                 return err;
6264         }
6265         lock_buffer(bh);
6266         memcpy(bh->b_data+offset, data, len);
6267         flush_dcache_page(bh->b_page);
6268         unlock_buffer(bh);
6269         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6270         brelse(bh);
6271 out:
6272         if (inode->i_size < off + len) {
6273                 i_size_write(inode, off + len);
6274                 EXT4_I(inode)->i_disksize = inode->i_size;
6275                 err2 = ext4_mark_inode_dirty(handle, inode);
6276                 if (unlikely(err2 && !err))
6277                         err = err2;
6278         }
6279         return err ? err : len;
6280 }
6281 #endif
6282
6283 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6284                        const char *dev_name, void *data)
6285 {
6286         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6287 }
6288
6289 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6290 static inline void register_as_ext2(void)
6291 {
6292         int err = register_filesystem(&ext2_fs_type);
6293         if (err)
6294                 printk(KERN_WARNING
6295                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6296 }
6297
6298 static inline void unregister_as_ext2(void)
6299 {
6300         unregister_filesystem(&ext2_fs_type);
6301 }
6302
6303 static inline int ext2_feature_set_ok(struct super_block *sb)
6304 {
6305         if (ext4_has_unknown_ext2_incompat_features(sb))
6306                 return 0;
6307         if (sb_rdonly(sb))
6308                 return 1;
6309         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6310                 return 0;
6311         return 1;
6312 }
6313 #else
6314 static inline void register_as_ext2(void) { }
6315 static inline void unregister_as_ext2(void) { }
6316 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6317 #endif
6318
6319 static inline void register_as_ext3(void)
6320 {
6321         int err = register_filesystem(&ext3_fs_type);
6322         if (err)
6323                 printk(KERN_WARNING
6324                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6325 }
6326
6327 static inline void unregister_as_ext3(void)
6328 {
6329         unregister_filesystem(&ext3_fs_type);
6330 }
6331
6332 static inline int ext3_feature_set_ok(struct super_block *sb)
6333 {
6334         if (ext4_has_unknown_ext3_incompat_features(sb))
6335                 return 0;
6336         if (!ext4_has_feature_journal(sb))
6337                 return 0;
6338         if (sb_rdonly(sb))
6339                 return 1;
6340         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6341                 return 0;
6342         return 1;
6343 }
6344
6345 static struct file_system_type ext4_fs_type = {
6346         .owner          = THIS_MODULE,
6347         .name           = "ext4",
6348         .mount          = ext4_mount,
6349         .kill_sb        = kill_block_super,
6350         .fs_flags       = FS_REQUIRES_DEV,
6351 };
6352 MODULE_ALIAS_FS("ext4");
6353
6354 /* Shared across all ext4 file systems */
6355 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6356
6357 static int __init ext4_init_fs(void)
6358 {
6359         int i, err;
6360
6361         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6362         ext4_li_info = NULL;
6363         mutex_init(&ext4_li_mtx);
6364
6365         /* Build-time check for flags consistency */
6366         ext4_check_flag_values();
6367
6368         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6369                 init_waitqueue_head(&ext4__ioend_wq[i]);
6370
6371         err = ext4_init_es();
6372         if (err)
6373                 return err;
6374
6375         err = ext4_init_pending();
6376         if (err)
6377                 goto out7;
6378
6379         err = ext4_init_post_read_processing();
6380         if (err)
6381                 goto out6;
6382
6383         err = ext4_init_pageio();
6384         if (err)
6385                 goto out5;
6386
6387         err = ext4_init_system_zone();
6388         if (err)
6389                 goto out4;
6390
6391         err = ext4_init_sysfs();
6392         if (err)
6393                 goto out3;
6394
6395         err = ext4_init_mballoc();
6396         if (err)
6397                 goto out2;
6398         err = init_inodecache();
6399         if (err)
6400                 goto out1;
6401         register_as_ext3();
6402         register_as_ext2();
6403         err = register_filesystem(&ext4_fs_type);
6404         if (err)
6405                 goto out;
6406
6407         return 0;
6408 out:
6409         unregister_as_ext2();
6410         unregister_as_ext3();
6411         destroy_inodecache();
6412 out1:
6413         ext4_exit_mballoc();
6414 out2:
6415         ext4_exit_sysfs();
6416 out3:
6417         ext4_exit_system_zone();
6418 out4:
6419         ext4_exit_pageio();
6420 out5:
6421         ext4_exit_post_read_processing();
6422 out6:
6423         ext4_exit_pending();
6424 out7:
6425         ext4_exit_es();
6426
6427         return err;
6428 }
6429
6430 static void __exit ext4_exit_fs(void)
6431 {
6432         ext4_destroy_lazyinit_thread();
6433         unregister_as_ext2();
6434         unregister_as_ext3();
6435         unregister_filesystem(&ext4_fs_type);
6436         destroy_inodecache();
6437         ext4_exit_mballoc();
6438         ext4_exit_sysfs();
6439         ext4_exit_system_zone();
6440         ext4_exit_pageio();
6441         ext4_exit_post_read_processing();
6442         ext4_exit_es();
6443         ext4_exit_pending();
6444 }
6445
6446 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6447 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6448 MODULE_LICENSE("GPL");
6449 MODULE_SOFTDEP("pre: crc32c");
6450 module_init(ext4_init_fs)
6451 module_exit(ext4_exit_fs)