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 static inline void __ext4_read_bh(struct buffer_head *bh, int op_flags,
 146                                   bh_end_io_t *end_io)
 147 {
 148         /*
 149          * buffer's verified bit is no longer valid after reading from
 150          * disk again due to write out error, clear it to make sure we
 151          * recheck the buffer contents.
 152          */
 153         clear_buffer_verified(bh);
 154
 155         bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
 156         get_bh(bh);
 157         submit_bh(REQ_OP_READ, op_flags, bh);
 158 }
 159
 160 void ext4_read_bh_nowait(struct buffer_head *bh, int op_flags,
 161                          bh_end_io_t *end_io)
 162 {
 163         BUG_ON(!buffer_locked(bh));
 164
 165         if (ext4_buffer_uptodate(bh)) {
 166                 unlock_buffer(bh);
 167                 return;
 168         }
 169         __ext4_read_bh(bh, op_flags, end_io);
 170 }
 171
 172 int ext4_read_bh(struct buffer_head *bh, int op_flags, bh_end_io_t *end_io)
 173 {
 174         BUG_ON(!buffer_locked(bh));
 175
 176         if (ext4_buffer_uptodate(bh)) {
 177                 unlock_buffer(bh);
 178                 return 0;
 179         }
 180
 181         __ext4_read_bh(bh, op_flags, end_io);
 182
 183         wait_on_buffer(bh);
 184         if (buffer_uptodate(bh))
 185                 return 0;
 186         return -EIO;
 187 }
 188
 189 int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait)
 190 {
 191         if (trylock_buffer(bh)) {
 192                 if (wait)
 193                         return ext4_read_bh(bh, op_flags, NULL);
 194                 ext4_read_bh_nowait(bh, op_flags, NULL);
 195                 return 0;
 196         }
 197         if (wait) {
 198                 wait_on_buffer(bh);
 199                 if (buffer_uptodate(bh))
 200                         return 0;
 201                 return -EIO;
 202         }
 203         return 0;
 204 }
 205
 206 /*
 207  * This works like __bread_gfp() except it uses ERR_PTR for error
 208  * returns.  Currently with sb_bread it's impossible to distinguish
 209  * between ENOMEM and EIO situations (since both result in a NULL
 210  * return.
 211  */
 212 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
 213                                                sector_t block, int op_flags,
 214                                                gfp_t gfp)
 215 {
 216         struct buffer_head *bh;
 217         int ret;
 218
 219         bh = sb_getblk_gfp(sb, block, gfp);
 220         if (bh == NULL)
 221                 return ERR_PTR(-ENOMEM);
 222         if (ext4_buffer_uptodate(bh))
 223                 return bh;
 224
 225         ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
 226         if (ret) {
 227                 put_bh(bh);
 228                 return ERR_PTR(ret);
 229         }
 230         return bh;
 231 }
 232
 233 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
 234                                    int op_flags)
 235 {
 236         return __ext4_sb_bread_gfp(sb, block, op_flags, __GFP_MOVABLE);
 237 }
 238
 239 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
 240                                             sector_t block)
 241 {
 242         return __ext4_sb_bread_gfp(sb, block, 0, 0);
 243 }
 244
 245 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
 246 {
 247         struct buffer_head *bh = sb_getblk_gfp(sb, block, 0);
 248
 249         if (likely(bh)) {
 250                 ext4_read_bh_lock(bh, REQ_RAHEAD, false);
 251                 brelse(bh);
 252         }
 253 }
 254
 255 static int ext4_verify_csum_type(struct super_block *sb,
 256                                  struct ext4_super_block *es)
 257 {
 258         if (!ext4_has_feature_metadata_csum(sb))
 259                 return 1;
 260
 261         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 262 }
 263
 264 static __le32 ext4_superblock_csum(struct super_block *sb,
 265                                    struct ext4_super_block *es)
 266 {
 267         struct ext4_sb_info *sbi = EXT4_SB(sb);
 268         int offset = offsetof(struct ext4_super_block, s_checksum);
 269         __u32 csum;
 270
 271         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 272
 273         return cpu_to_le32(csum);
 274 }
 275
 276 static int ext4_superblock_csum_verify(struct super_block *sb,
 277                                        struct ext4_super_block *es)
 278 {
 279         if (!ext4_has_metadata_csum(sb))
 280                 return 1;
 281
 282         return es->s_checksum == ext4_superblock_csum(sb, es);
 283 }
 284
 285 void ext4_superblock_csum_set(struct super_block *sb)
 286 {
 287         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 288
 289         if (!ext4_has_metadata_csum(sb))
 290                 return;
 291
 292         /*
 293          * Locking the superblock prevents the scenario
 294          * where:
 295          *  1) a first thread pauses during checksum calculation.
 296          *  2) a second thread updates the superblock, recalculates
 297          *     the checksum, and updates s_checksum
 298          *  3) the first thread resumes and finishes its checksum calculation
 299          *     and updates s_checksum with a potentially stale or torn value.
 300          */
 301         lock_buffer(EXT4_SB(sb)->s_sbh);
 302         es->s_checksum = ext4_superblock_csum(sb, es);
 303         unlock_buffer(EXT4_SB(sb)->s_sbh);
 304 }
 305
 306 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 307                                struct ext4_group_desc *bg)
 308 {
 309         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 310                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 311                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 312 }
 313
 314 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 315                                struct ext4_group_desc *bg)
 316 {
 317         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 318                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 319                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 320 }
 321
 322 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 323                               struct ext4_group_desc *bg)
 324 {
 325         return le32_to_cpu(bg->bg_inode_table_lo) |
 326                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 327                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 328 }
 329
 330 __u32 ext4_free_group_clusters(struct super_block *sb,
 331                                struct ext4_group_desc *bg)
 332 {
 333         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 334                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 335                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 336 }
 337
 338 __u32 ext4_free_inodes_count(struct super_block *sb,
 339                               struct ext4_group_desc *bg)
 340 {
 341         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 342                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 343                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 344 }
 345
 346 __u32 ext4_used_dirs_count(struct super_block *sb,
 347                               struct ext4_group_desc *bg)
 348 {
 349         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 350                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 351                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 352 }
 353
 354 __u32 ext4_itable_unused_count(struct super_block *sb,
 355                               struct ext4_group_desc *bg)
 356 {
 357         return le16_to_cpu(bg->bg_itable_unused_lo) |
 358                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 359                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 360 }
 361
 362 void ext4_block_bitmap_set(struct super_block *sb,
 363                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 364 {
 365         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 366         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 367                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 368 }
 369
 370 void ext4_inode_bitmap_set(struct super_block *sb,
 371                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 372 {
 373         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 374         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 375                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 376 }
 377
 378 void ext4_inode_table_set(struct super_block *sb,
 379                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 380 {
 381         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 382         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 383                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 384 }
 385
 386 void ext4_free_group_clusters_set(struct super_block *sb,
 387                                   struct ext4_group_desc *bg, __u32 count)
 388 {
 389         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 390         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 391                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 392 }
 393
 394 void ext4_free_inodes_set(struct super_block *sb,
 395                           struct ext4_group_desc *bg, __u32 count)
 396 {
 397         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 398         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 399                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 400 }
 401
 402 void ext4_used_dirs_set(struct super_block *sb,
 403                           struct ext4_group_desc *bg, __u32 count)
 404 {
 405         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 406         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 407                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 408 }
 409
 410 void ext4_itable_unused_set(struct super_block *sb,
 411                           struct ext4_group_desc *bg, __u32 count)
 412 {
 413         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 414         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 415                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 416 }
 417
 418 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi)
 419 {
 420         time64_t now = ktime_get_real_seconds();
 421
 422         now = clamp_val(now, 0, (1ull << 40) - 1);
 423
 424         *lo = cpu_to_le32(lower_32_bits(now));
 425         *hi = upper_32_bits(now);
 426 }
 427
 428 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 429 {
 430         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 431 }
 432 #define ext4_update_tstamp(es, tstamp) \
 433         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 434 #define ext4_get_tstamp(es, tstamp) \
 435         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 436
 437 static void __save_error_info(struct super_block *sb, int error,
 438                               __u32 ino, __u64 block,
 439                               const char *func, unsigned int line)
 440 {
 441         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 442         int err;
 443
 444         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 445         if (bdev_read_only(sb->s_bdev))
 446                 return;
 447         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 448         ext4_update_tstamp(es, s_last_error_time);
 449         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 450         es->s_last_error_line = cpu_to_le32(line);
 451         es->s_last_error_ino = cpu_to_le32(ino);
 452         es->s_last_error_block = cpu_to_le64(block);
 453         switch (error) {
 454         case EIO:
 455                 err = EXT4_ERR_EIO;
 456                 break;
 457         case ENOMEM:
 458                 err = EXT4_ERR_ENOMEM;
 459                 break;
 460         case EFSBADCRC:
 461                 err = EXT4_ERR_EFSBADCRC;
 462                 break;
 463         case 0:
 464         case EFSCORRUPTED:
 465                 err = EXT4_ERR_EFSCORRUPTED;
 466                 break;
 467         case ENOSPC:
 468                 err = EXT4_ERR_ENOSPC;
 469                 break;
 470         case ENOKEY:
 471                 err = EXT4_ERR_ENOKEY;
 472                 break;
 473         case EROFS:
 474                 err = EXT4_ERR_EROFS;
 475                 break;
 476         case EFBIG:
 477                 err = EXT4_ERR_EFBIG;
 478                 break;
 479         case EEXIST:
 480                 err = EXT4_ERR_EEXIST;
 481                 break;
 482         case ERANGE:
 483                 err = EXT4_ERR_ERANGE;
 484                 break;
 485         case EOVERFLOW:
 486                 err = EXT4_ERR_EOVERFLOW;
 487                 break;
 488         case EBUSY:
 489                 err = EXT4_ERR_EBUSY;
 490                 break;
 491         case ENOTDIR:
 492                 err = EXT4_ERR_ENOTDIR;
 493                 break;
 494         case ENOTEMPTY:
 495                 err = EXT4_ERR_ENOTEMPTY;
 496                 break;
 497         case ESHUTDOWN:
 498                 err = EXT4_ERR_ESHUTDOWN;
 499                 break;
 500         case EFAULT:
 501                 err = EXT4_ERR_EFAULT;
 502                 break;
 503         default:
 504                 err = EXT4_ERR_UNKNOWN;
 505         }
 506         es->s_last_error_errcode = err;
 507         if (!es->s_first_error_time) {
 508                 es->s_first_error_time = es->s_last_error_time;
 509                 es->s_first_error_time_hi = es->s_last_error_time_hi;
 510                 strncpy(es->s_first_error_func, func,
 511                         sizeof(es->s_first_error_func));
 512                 es->s_first_error_line = cpu_to_le32(line);
 513                 es->s_first_error_ino = es->s_last_error_ino;
 514                 es->s_first_error_block = es->s_last_error_block;
 515                 es->s_first_error_errcode = es->s_last_error_errcode;
 516         }
 517         /*
 518          * Start the daily error reporting function if it hasn't been
 519          * started already
 520          */
 521         if (!es->s_error_count)
 522                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 523         le32_add_cpu(&es->s_error_count, 1);
 524 }
 525
 526 static void save_error_info(struct super_block *sb, int error,
 527                             __u32 ino, __u64 block,
 528                             const char *func, unsigned int line)
 529 {
 530         __save_error_info(sb, error, ino, block, func, line);
 531         if (!bdev_read_only(sb->s_bdev))
 532                 ext4_commit_super(sb, 1);
 533 }
 534
 535 /*
 536  * The del_gendisk() function uninitializes the disk-specific data
 537  * structures, including the bdi structure, without telling anyone
 538  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 539  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 540  * This is a kludge to prevent these oops until we can put in a proper
 541  * hook in del_gendisk() to inform the VFS and file system layers.
 542  */
 543 static int block_device_ejected(struct super_block *sb)
 544 {
 545         struct inode *bd_inode = sb->s_bdev->bd_inode;
 546         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 547
 548         return bdi->dev == NULL;
 549 }
 550
 551 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 552 {
 553         struct super_block              *sb = journal->j_private;
 554         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 555         int                             error = is_journal_aborted(journal);
 556         struct ext4_journal_cb_entry    *jce;
 557
 558         BUG_ON(txn->t_state == T_FINISHED);
 559
 560         ext4_process_freed_data(sb, txn->t_tid);
 561
 562         spin_lock(&sbi->s_md_lock);
 563         while (!list_empty(&txn->t_private_list)) {
 564                 jce = list_entry(txn->t_private_list.next,
 565                                  struct ext4_journal_cb_entry, jce_list);
 566                 list_del_init(&jce->jce_list);
 567                 spin_unlock(&sbi->s_md_lock);
 568                 jce->jce_func(sb, jce, error);
 569                 spin_lock(&sbi->s_md_lock);
 570         }
 571         spin_unlock(&sbi->s_md_lock);
 572 }
 573
 574 /*
 575  * This writepage callback for write_cache_pages()
 576  * takes care of a few cases after page cleaning.
 577  *
 578  * write_cache_pages() already checks for dirty pages
 579  * and calls clear_page_dirty_for_io(), which we want,
 580  * to write protect the pages.
 581  *
 582  * However, we may have to redirty a page (see below.)
 583  */
 584 static int ext4_journalled_writepage_callback(struct page *page,
 585                                               struct writeback_control *wbc,
 586                                               void *data)
 587 {
 588         transaction_t *transaction = (transaction_t *) data;
 589         struct buffer_head *bh, *head;
 590         struct journal_head *jh;
 591
 592         bh = head = page_buffers(page);
 593         do {
 594                 /*
 595                  * We have to redirty a page in these cases:
 596                  * 1) If buffer is dirty, it means the page was dirty because it
 597                  * contains a buffer that needs checkpointing. So the dirty bit
 598                  * needs to be preserved so that checkpointing writes the buffer
 599                  * properly.
 600                  * 2) If buffer is not part of the committing transaction
 601                  * (we may have just accidentally come across this buffer because
 602                  * inode range tracking is not exact) or if the currently running
 603                  * transaction already contains this buffer as well, dirty bit
 604                  * needs to be preserved so that the buffer gets writeprotected
 605                  * properly on running transaction's commit.
 606                  */
 607                 jh = bh2jh(bh);
 608                 if (buffer_dirty(bh) ||
 609                     (jh && (jh->b_transaction != transaction ||
 610                             jh->b_next_transaction))) {
 611                         redirty_page_for_writepage(wbc, page);
 612                         goto out;
 613                 }
 614         } while ((bh = bh->b_this_page) != head);
 615
 616 out:
 617         return AOP_WRITEPAGE_ACTIVATE;
 618 }
 619
 620 static int ext4_journalled_submit_inode_data_buffers(struct jbd2_inode *jinode)
 621 {
 622         struct address_space *mapping = jinode->i_vfs_inode->i_mapping;
 623         struct writeback_control wbc = {
 624                 .sync_mode =  WB_SYNC_ALL,
 625                 .nr_to_write = LONG_MAX,
 626                 .range_start = jinode->i_dirty_start,
 627                 .range_end = jinode->i_dirty_end,
 628         };
 629
 630         return write_cache_pages(mapping, &wbc,
 631                                  ext4_journalled_writepage_callback,
 632                                  jinode->i_transaction);
 633 }
 634
 635 static int ext4_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
 636 {
 637         int ret;
 638
 639         if (ext4_should_journal_data(jinode->i_vfs_inode))
 640                 ret = ext4_journalled_submit_inode_data_buffers(jinode);
 641         else
 642                 ret = jbd2_journal_submit_inode_data_buffers(jinode);
 643
 644         return ret;
 645 }
 646
 647 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
 648 {
 649         int ret = 0;
 650
 651         if (!ext4_should_journal_data(jinode->i_vfs_inode))
 652                 ret = jbd2_journal_finish_inode_data_buffers(jinode);
 653
 654         return ret;
 655 }
 656
 657 static bool system_going_down(void)
 658 {
 659         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 660                 || system_state == SYSTEM_RESTART;
 661 }
 662
 663 /* Deal with the reporting of failure conditions on a filesystem such as
 664  * inconsistencies detected or read IO failures.
 665  *
 666  * On ext2, we can store the error state of the filesystem in the
 667  * superblock.  That is not possible on ext4, because we may have other
 668  * write ordering constraints on the superblock which prevent us from
 669  * writing it out straight away; and given that the journal is about to
 670  * be aborted, we can't rely on the current, or future, transactions to
 671  * write out the superblock safely.
 672  *
 673  * We'll just use the jbd2_journal_abort() error code to record an error in
 674  * the journal instead.  On recovery, the journal will complain about
 675  * that error until we've noted it down and cleared it.
 676  */
 677
 678 static void ext4_handle_error(struct super_block *sb)
 679 {
 680         if (test_opt(sb, WARN_ON_ERROR))
 681                 WARN_ON_ONCE(1);
 682
 683         if (sb_rdonly(sb))
 684                 return;
 685
 686         if (!test_opt(sb, ERRORS_CONT)) {
 687                 journal_t *journal = EXT4_SB(sb)->s_journal;
 688
 689                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 690                 if (journal)
 691                         jbd2_journal_abort(journal, -EIO);
 692         }
 693         /*
 694          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 695          * could panic during 'reboot -f' as the underlying device got already
 696          * disabled.
 697          */
 698         if (test_opt(sb, ERRORS_RO) || system_going_down()) {
 699                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 700                 /*
 701                  * Make sure updated value of ->s_mount_flags will be visible
 702                  * before ->s_flags update
 703                  */
 704                 smp_wmb();
 705                 sb->s_flags |= SB_RDONLY;
 706         } else if (test_opt(sb, ERRORS_PANIC)) {
 707                 panic("EXT4-fs (device %s): panic forced after error\n",
 708                         sb->s_id);
 709         }
 710 }
 711
 712 #define ext4_error_ratelimit(sb)                                        \
 713                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 714                              "EXT4-fs error")
 715
 716 void __ext4_error(struct super_block *sb, const char *function,
 717                   unsigned int line, int error, __u64 block,
 718                   const char *fmt, ...)
 719 {
 720         struct va_format vaf;
 721         va_list args;
 722
 723         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 724                 return;
 725
 726         trace_ext4_error(sb, function, line);
 727         if (ext4_error_ratelimit(sb)) {
 728                 va_start(args, fmt);
 729                 vaf.fmt = fmt;
 730                 vaf.va = &args;
 731                 printk(KERN_CRIT
 732                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 733                        sb->s_id, function, line, current->comm, &vaf);
 734                 va_end(args);
 735         }
 736         save_error_info(sb, error, 0, block, function, line);
 737         ext4_handle_error(sb);
 738 }
 739
 740 void __ext4_error_inode(struct inode *inode, const char *function,
 741                         unsigned int line, ext4_fsblk_t block, int error,
 742                         const char *fmt, ...)
 743 {
 744         va_list args;
 745         struct va_format vaf;
 746
 747         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 748                 return;
 749
 750         trace_ext4_error(inode->i_sb, function, line);
 751         if (ext4_error_ratelimit(inode->i_sb)) {
 752                 va_start(args, fmt);
 753                 vaf.fmt = fmt;
 754                 vaf.va = &args;
 755                 if (block)
 756                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 757                                "inode #%lu: block %llu: comm %s: %pV\n",
 758                                inode->i_sb->s_id, function, line, inode->i_ino,
 759                                block, current->comm, &vaf);
 760                 else
 761                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 762                                "inode #%lu: comm %s: %pV\n",
 763                                inode->i_sb->s_id, function, line, inode->i_ino,
 764                                current->comm, &vaf);
 765                 va_end(args);
 766         }
 767         save_error_info(inode->i_sb, error, inode->i_ino, block,
 768                         function, line);
 769         ext4_handle_error(inode->i_sb);
 770 }
 771
 772 void __ext4_error_file(struct file *file, const char *function,
 773                        unsigned int line, ext4_fsblk_t block,
 774                        const char *fmt, ...)
 775 {
 776         va_list args;
 777         struct va_format vaf;
 778         struct inode *inode = file_inode(file);
 779         char pathname[80], *path;
 780
 781         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 782                 return;
 783
 784         trace_ext4_error(inode->i_sb, function, line);
 785         if (ext4_error_ratelimit(inode->i_sb)) {
 786                 path = file_path(file, pathname, sizeof(pathname));
 787                 if (IS_ERR(path))
 788                         path = "(unknown)";
 789                 va_start(args, fmt);
 790                 vaf.fmt = fmt;
 791                 vaf.va = &args;
 792                 if (block)
 793                         printk(KERN_CRIT
 794                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 795                                "block %llu: comm %s: path %s: %pV\n",
 796                                inode->i_sb->s_id, function, line, inode->i_ino,
 797                                block, current->comm, path, &vaf);
 798                 else
 799                         printk(KERN_CRIT
 800                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 801                                "comm %s: path %s: %pV\n",
 802                                inode->i_sb->s_id, function, line, inode->i_ino,
 803                                current->comm, path, &vaf);
 804                 va_end(args);
 805         }
 806         save_error_info(inode->i_sb, EFSCORRUPTED, inode->i_ino, block,
 807                         function, line);
 808         ext4_handle_error(inode->i_sb);
 809 }
 810
 811 const char *ext4_decode_error(struct super_block *sb, int errno,
 812                               char nbuf[16])
 813 {
 814         char *errstr = NULL;
 815
 816         switch (errno) {
 817         case -EFSCORRUPTED:
 818                 errstr = "Corrupt filesystem";
 819                 break;
 820         case -EFSBADCRC:
 821                 errstr = "Filesystem failed CRC";
 822                 break;
 823         case -EIO:
 824                 errstr = "IO failure";
 825                 break;
 826         case -ENOMEM:
 827                 errstr = "Out of memory";
 828                 break;
 829         case -EROFS:
 830                 if (!sb || (EXT4_SB(sb)->s_journal &&
 831                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 832                         errstr = "Journal has aborted";
 833                 else
 834                         errstr = "Readonly filesystem";
 835                 break;
 836         default:
 837                 /* If the caller passed in an extra buffer for unknown
 838                  * errors, textualise them now.  Else we just return
 839                  * NULL. */
 840                 if (nbuf) {
 841                         /* Check for truncated error codes... */
 842                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 843                                 errstr = nbuf;
 844                 }
 845                 break;
 846         }
 847
 848         return errstr;
 849 }
 850
 851 /* __ext4_std_error decodes expected errors from journaling functions
 852  * automatically and invokes the appropriate error response.  */
 853
 854 void __ext4_std_error(struct super_block *sb, const char *function,
 855                       unsigned int line, int errno)
 856 {
 857         char nbuf[16];
 858         const char *errstr;
 859
 860         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 861                 return;
 862
 863         /* Special case: if the error is EROFS, and we're not already
 864          * inside a transaction, then there's really no point in logging
 865          * an error. */
 866         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 867                 return;
 868
 869         if (ext4_error_ratelimit(sb)) {
 870                 errstr = ext4_decode_error(sb, errno, nbuf);
 871                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 872                        sb->s_id, function, line, errstr);
 873         }
 874
 875         save_error_info(sb, -errno, 0, 0, function, line);
 876         ext4_handle_error(sb);
 877 }
 878
 879 /*
 880  * ext4_abort is a much stronger failure handler than ext4_error.  The
 881  * abort function may be used to deal with unrecoverable failures such
 882  * as journal IO errors or ENOMEM at a critical moment in log management.
 883  *
 884  * We unconditionally force the filesystem into an ABORT|READONLY state,
 885  * unless the error response on the fs has been set to panic in which
 886  * case we take the easy way out and panic immediately.
 887  */
 888
 889 void __ext4_abort(struct super_block *sb, const char *function,
 890                   unsigned int line, int error, const char *fmt, ...)
 891 {
 892         struct va_format vaf;
 893         va_list args;
 894
 895         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 896                 return;
 897
 898         save_error_info(sb, error, 0, 0, function, line);
 899         va_start(args, fmt);
 900         vaf.fmt = fmt;
 901         vaf.va = &args;
 902         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 903                sb->s_id, function, line, &vaf);
 904         va_end(args);
 905
 906         if (sb_rdonly(sb) == 0) {
 907                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 908                 if (EXT4_SB(sb)->s_journal)
 909                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 910
 911                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 912                 /*
 913                  * Make sure updated value of ->s_mount_flags will be visible
 914                  * before ->s_flags update
 915                  */
 916                 smp_wmb();
 917                 sb->s_flags |= SB_RDONLY;
 918         }
 919         if (test_opt(sb, ERRORS_PANIC) && !system_going_down())
 920                 panic("EXT4-fs panic from previous error\n");
 921 }
 922
 923 void __ext4_msg(struct super_block *sb,
 924                 const char *prefix, const char *fmt, ...)
 925 {
 926         struct va_format vaf;
 927         va_list args;
 928
 929         atomic_inc(&EXT4_SB(sb)->s_msg_count);
 930         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 931                 return;
 932
 933         va_start(args, fmt);
 934         vaf.fmt = fmt;
 935         vaf.va = &args;
 936         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 937         va_end(args);
 938 }
 939
 940 static int ext4_warning_ratelimit(struct super_block *sb)
 941 {
 942         atomic_inc(&EXT4_SB(sb)->s_warning_count);
 943         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
 944                             "EXT4-fs warning");
 945 }
 946
 947 void __ext4_warning(struct super_block *sb, const char *function,
 948                     unsigned int line, const char *fmt, ...)
 949 {
 950         struct va_format vaf;
 951         va_list args;
 952
 953         if (!ext4_warning_ratelimit(sb))
 954                 return;
 955
 956         va_start(args, fmt);
 957         vaf.fmt = fmt;
 958         vaf.va = &args;
 959         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 960                sb->s_id, function, line, &vaf);
 961         va_end(args);
 962 }
 963
 964 void __ext4_warning_inode(const struct inode *inode, const char *function,
 965                           unsigned int line, const char *fmt, ...)
 966 {
 967         struct va_format vaf;
 968         va_list args;
 969
 970         if (!ext4_warning_ratelimit(inode->i_sb))
 971                 return;
 972
 973         va_start(args, fmt);
 974         vaf.fmt = fmt;
 975         vaf.va = &args;
 976         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 977                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 978                function, line, inode->i_ino, current->comm, &vaf);
 979         va_end(args);
 980 }
 981
 982 void __ext4_grp_locked_error(const char *function, unsigned int line,
 983                              struct super_block *sb, ext4_group_t grp,
 984                              unsigned long ino, ext4_fsblk_t block,
 985                              const char *fmt, ...)
 986 __releases(bitlock)
 987 __acquires(bitlock)
 988 {
 989         struct va_format vaf;
 990         va_list args;
 991
 992         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 993                 return;
 994
 995         trace_ext4_error(sb, function, line);
 996         __save_error_info(sb, EFSCORRUPTED, ino, block, function, line);
 997
 998         if (ext4_error_ratelimit(sb)) {
 999                 va_start(args, fmt);
1000                 vaf.fmt = fmt;
1001                 vaf.va = &args;
1002                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
1003                        sb->s_id, function, line, grp);
1004                 if (ino)
1005                         printk(KERN_CONT "inode %lu: ", ino);
1006                 if (block)
1007                         printk(KERN_CONT "block %llu:",
1008                                (unsigned long long) block);
1009                 printk(KERN_CONT "%pV\n", &vaf);
1010                 va_end(args);
1011         }
1012
1013         if (test_opt(sb, WARN_ON_ERROR))
1014                 WARN_ON_ONCE(1);
1015
1016         if (test_opt(sb, ERRORS_CONT)) {
1017                 ext4_commit_super(sb, 0);
1018                 return;
1019         }
1020
1021         ext4_unlock_group(sb, grp);
1022         ext4_commit_super(sb, 1);
1023         ext4_handle_error(sb);
1024         /*
1025          * We only get here in the ERRORS_RO case; relocking the group
1026          * may be dangerous, but nothing bad will happen since the
1027          * filesystem will have already been marked read/only and the
1028          * journal has been aborted.  We return 1 as a hint to callers
1029          * who might what to use the return value from
1030          * ext4_grp_locked_error() to distinguish between the
1031          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1032          * aggressively from the ext4 function in question, with a
1033          * more appropriate error code.
1034          */
1035         ext4_lock_group(sb, grp);
1036         return;
1037 }
1038
1039 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1040                                      ext4_group_t group,
1041                                      unsigned int flags)
1042 {
1043         struct ext4_sb_info *sbi = EXT4_SB(sb);
1044         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1045         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1046         int ret;
1047
1048         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1049                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1050                                             &grp->bb_state);
1051                 if (!ret)
1052                         percpu_counter_sub(&sbi->s_freeclusters_counter,
1053                                            grp->bb_free);
1054         }
1055
1056         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1057                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1058                                             &grp->bb_state);
1059                 if (!ret && gdp) {
1060                         int count;
1061
1062                         count = ext4_free_inodes_count(sb, gdp);
1063                         percpu_counter_sub(&sbi->s_freeinodes_counter,
1064                                            count);
1065                 }
1066         }
1067 }
1068
1069 void ext4_update_dynamic_rev(struct super_block *sb)
1070 {
1071         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1072
1073         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1074                 return;
1075
1076         ext4_warning(sb,
1077                      "updating to rev %d because of new feature flag, "
1078                      "running e2fsck is recommended",
1079                      EXT4_DYNAMIC_REV);
1080
1081         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1082         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1083         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1084         /* leave es->s_feature_*compat flags alone */
1085         /* es->s_uuid will be set by e2fsck if empty */
1086
1087         /*
1088          * The rest of the superblock fields should be zero, and if not it
1089          * means they are likely already in use, so leave them alone.  We
1090          * can leave it up to e2fsck to clean up any inconsistencies there.
1091          */
1092 }
1093
1094 /*
1095  * Open the external journal device
1096  */
1097 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
1098 {
1099         struct block_device *bdev;
1100
1101         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
1102         if (IS_ERR(bdev))
1103                 goto fail;
1104         return bdev;
1105
1106 fail:
1107         ext4_msg(sb, KERN_ERR,
1108                  "failed to open journal device unknown-block(%u,%u) %ld",
1109                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
1110         return NULL;
1111 }
1112
1113 /*
1114  * Release the journal device
1115  */
1116 static void ext4_blkdev_put(struct block_device *bdev)
1117 {
1118         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1119 }
1120
1121 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
1122 {
1123         struct block_device *bdev;
1124         bdev = sbi->s_journal_bdev;
1125         if (bdev) {
1126                 ext4_blkdev_put(bdev);
1127                 sbi->s_journal_bdev = NULL;
1128         }
1129 }
1130
1131 static inline struct inode *orphan_list_entry(struct list_head *l)
1132 {
1133         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1134 }
1135
1136 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1137 {
1138         struct list_head *l;
1139
1140         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1141                  le32_to_cpu(sbi->s_es->s_last_orphan));
1142
1143         printk(KERN_ERR "sb_info orphan list:\n");
1144         list_for_each(l, &sbi->s_orphan) {
1145                 struct inode *inode = orphan_list_entry(l);
1146                 printk(KERN_ERR "  "
1147                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1148                        inode->i_sb->s_id, inode->i_ino, inode,
1149                        inode->i_mode, inode->i_nlink,
1150                        NEXT_ORPHAN(inode));
1151         }
1152 }
1153
1154 #ifdef CONFIG_QUOTA
1155 static int ext4_quota_off(struct super_block *sb, int type);
1156
1157 static inline void ext4_quota_off_umount(struct super_block *sb)
1158 {
1159         int type;
1160
1161         /* Use our quota_off function to clear inode flags etc. */
1162         for (type = 0; type < EXT4_MAXQUOTAS; type++)
1163                 ext4_quota_off(sb, type);
1164 }
1165
1166 /*
1167  * This is a helper function which is used in the mount/remount
1168  * codepaths (which holds s_umount) to fetch the quota file name.
1169  */
1170 static inline char *get_qf_name(struct super_block *sb,
1171                                 struct ext4_sb_info *sbi,
1172                                 int type)
1173 {
1174         return rcu_dereference_protected(sbi->s_qf_names[type],
1175                                          lockdep_is_held(&sb->s_umount));
1176 }
1177 #else
1178 static inline void ext4_quota_off_umount(struct super_block *sb)
1179 {
1180 }
1181 #endif
1182
1183 static void ext4_put_super(struct super_block *sb)
1184 {
1185         struct ext4_sb_info *sbi = EXT4_SB(sb);
1186         struct ext4_super_block *es = sbi->s_es;
1187         struct buffer_head **group_desc;
1188         struct flex_groups **flex_groups;
1189         int aborted = 0;
1190         int i, err;
1191
1192         ext4_unregister_li_request(sb);
1193         ext4_quota_off_umount(sb);
1194
1195         destroy_workqueue(sbi->rsv_conversion_wq);
1196
1197         /*
1198          * Unregister sysfs before destroying jbd2 journal.
1199          * Since we could still access attr_journal_task attribute via sysfs
1200          * path which could have sbi->s_journal->j_task as NULL
1201          */
1202         ext4_unregister_sysfs(sb);
1203
1204         if (sbi->s_journal) {
1205                 aborted = is_journal_aborted(sbi->s_journal);
1206                 err = jbd2_journal_destroy(sbi->s_journal);
1207                 sbi->s_journal = NULL;
1208                 if ((err < 0) && !aborted) {
1209                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1210                 }
1211         }
1212
1213         ext4_es_unregister_shrinker(sbi);
1214         del_timer_sync(&sbi->s_err_report);
1215         ext4_release_system_zone(sb);
1216         ext4_mb_release(sb);
1217         ext4_ext_release(sb);
1218
1219         if (!sb_rdonly(sb) && !aborted) {
1220                 ext4_clear_feature_journal_needs_recovery(sb);
1221                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1222         }
1223         if (!sb_rdonly(sb))
1224                 ext4_commit_super(sb, 1);
1225
1226         rcu_read_lock();
1227         group_desc = rcu_dereference(sbi->s_group_desc);
1228         for (i = 0; i < sbi->s_gdb_count; i++)
1229                 brelse(group_desc[i]);
1230         kvfree(group_desc);
1231         flex_groups = rcu_dereference(sbi->s_flex_groups);
1232         if (flex_groups) {
1233                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1234                         kvfree(flex_groups[i]);
1235                 kvfree(flex_groups);
1236         }
1237         rcu_read_unlock();
1238         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1239         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1240         percpu_counter_destroy(&sbi->s_dirs_counter);
1241         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1242         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1243 #ifdef CONFIG_QUOTA
1244         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1245                 kfree(get_qf_name(sb, sbi, i));
1246 #endif
1247
1248         /* Debugging code just in case the in-memory inode orphan list
1249          * isn't empty.  The on-disk one can be non-empty if we've
1250          * detected an error and taken the fs readonly, but the
1251          * in-memory list had better be clean by this point. */
1252         if (!list_empty(&sbi->s_orphan))
1253                 dump_orphan_list(sb, sbi);
1254         J_ASSERT(list_empty(&sbi->s_orphan));
1255
1256         sync_blockdev(sb->s_bdev);
1257         invalidate_bdev(sb->s_bdev);
1258         if (sbi->s_journal_bdev && sbi->s_journal_bdev != sb->s_bdev) {
1259                 /*
1260                  * Invalidate the journal device's buffers.  We don't want them
1261                  * floating about in memory - the physical journal device may
1262                  * hotswapped, and it breaks the `ro-after' testing code.
1263                  */
1264                 sync_blockdev(sbi->s_journal_bdev);
1265                 invalidate_bdev(sbi->s_journal_bdev);
1266                 ext4_blkdev_remove(sbi);
1267         }
1268
1269         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1270         sbi->s_ea_inode_cache = NULL;
1271
1272         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1273         sbi->s_ea_block_cache = NULL;
1274
1275         if (sbi->s_mmp_tsk)
1276                 kthread_stop(sbi->s_mmp_tsk);
1277         brelse(sbi->s_sbh);
1278         sb->s_fs_info = NULL;
1279         /*
1280          * Now that we are completely done shutting down the
1281          * superblock, we need to actually destroy the kobject.
1282          */
1283         kobject_put(&sbi->s_kobj);
1284         wait_for_completion(&sbi->s_kobj_unregister);
1285         if (sbi->s_chksum_driver)
1286                 crypto_free_shash(sbi->s_chksum_driver);
1287         kfree(sbi->s_blockgroup_lock);
1288         fs_put_dax(sbi->s_daxdev);
1289         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1290 #ifdef CONFIG_UNICODE
1291         utf8_unload(sbi->s_encoding);
1292 #endif
1293         kfree(sbi);
1294 }
1295
1296 static struct kmem_cache *ext4_inode_cachep;
1297
1298 /*
1299  * Called inside transaction, so use GFP_NOFS
1300  */
1301 static struct inode *ext4_alloc_inode(struct super_block *sb)
1302 {
1303         struct ext4_inode_info *ei;
1304
1305         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1306         if (!ei)
1307                 return NULL;
1308
1309         inode_set_iversion(&ei->vfs_inode, 1);
1310         spin_lock_init(&ei->i_raw_lock);
1311         INIT_LIST_HEAD(&ei->i_prealloc_list);
1312         atomic_set(&ei->i_prealloc_active, 0);
1313         spin_lock_init(&ei->i_prealloc_lock);
1314         ext4_es_init_tree(&ei->i_es_tree);
1315         rwlock_init(&ei->i_es_lock);
1316         INIT_LIST_HEAD(&ei->i_es_list);
1317         ei->i_es_all_nr = 0;
1318         ei->i_es_shk_nr = 0;
1319         ei->i_es_shrink_lblk = 0;
1320         ei->i_reserved_data_blocks = 0;
1321         spin_lock_init(&(ei->i_block_reservation_lock));
1322         ext4_init_pending_tree(&ei->i_pending_tree);
1323 #ifdef CONFIG_QUOTA
1324         ei->i_reserved_quota = 0;
1325         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1326 #endif
1327         ei->jinode = NULL;
1328         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1329         spin_lock_init(&ei->i_completed_io_lock);
1330         ei->i_sync_tid = 0;
1331         ei->i_datasync_tid = 0;
1332         atomic_set(&ei->i_unwritten, 0);
1333         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1334         ext4_fc_init_inode(&ei->vfs_inode);
1335         mutex_init(&ei->i_fc_lock);
1336         return &ei->vfs_inode;
1337 }
1338
1339 static int ext4_drop_inode(struct inode *inode)
1340 {
1341         int drop = generic_drop_inode(inode);
1342
1343         if (!drop)
1344                 drop = fscrypt_drop_inode(inode);
1345
1346         trace_ext4_drop_inode(inode, drop);
1347         return drop;
1348 }
1349
1350 static void ext4_free_in_core_inode(struct inode *inode)
1351 {
1352         fscrypt_free_inode(inode);
1353         if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1354                 pr_warn("%s: inode %ld still in fc list",
1355                         __func__, inode->i_ino);
1356         }
1357         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1358 }
1359
1360 static void ext4_destroy_inode(struct inode *inode)
1361 {
1362         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1363                 ext4_msg(inode->i_sb, KERN_ERR,
1364                          "Inode %lu (%p): orphan list check failed!",
1365                          inode->i_ino, EXT4_I(inode));
1366                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1367                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1368                                 true);
1369                 dump_stack();
1370         }
1371 }
1372
1373 static void init_once(void *foo)
1374 {
1375         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1376
1377         INIT_LIST_HEAD(&ei->i_orphan);
1378         init_rwsem(&ei->xattr_sem);
1379         init_rwsem(&ei->i_data_sem);
1380         init_rwsem(&ei->i_mmap_sem);
1381         inode_init_once(&ei->vfs_inode);
1382         ext4_fc_init_inode(&ei->vfs_inode);
1383 }
1384
1385 static int __init init_inodecache(void)
1386 {
1387         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1388                                 sizeof(struct ext4_inode_info), 0,
1389                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1390                                         SLAB_ACCOUNT),
1391                                 offsetof(struct ext4_inode_info, i_data),
1392                                 sizeof_field(struct ext4_inode_info, i_data),
1393                                 init_once);
1394         if (ext4_inode_cachep == NULL)
1395                 return -ENOMEM;
1396         return 0;
1397 }
1398
1399 static void destroy_inodecache(void)
1400 {
1401         /*
1402          * Make sure all delayed rcu free inodes are flushed before we
1403          * destroy cache.
1404          */
1405         rcu_barrier();
1406         kmem_cache_destroy(ext4_inode_cachep);
1407 }
1408
1409 void ext4_clear_inode(struct inode *inode)
1410 {
1411         ext4_fc_del(inode);
1412         invalidate_inode_buffers(inode);
1413         clear_inode(inode);
1414         ext4_discard_preallocations(inode, 0);
1415         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1416         dquot_drop(inode);
1417         if (EXT4_I(inode)->jinode) {
1418                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1419                                                EXT4_I(inode)->jinode);
1420                 jbd2_free_inode(EXT4_I(inode)->jinode);
1421                 EXT4_I(inode)->jinode = NULL;
1422         }
1423         fscrypt_put_encryption_info(inode);
1424         fsverity_cleanup_inode(inode);
1425 }
1426
1427 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1428                                         u64 ino, u32 generation)
1429 {
1430         struct inode *inode;
1431
1432         /*
1433          * Currently we don't know the generation for parent directory, so
1434          * a generation of 0 means "accept any"
1435          */
1436         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1437         if (IS_ERR(inode))
1438                 return ERR_CAST(inode);
1439         if (generation && inode->i_generation != generation) {
1440                 iput(inode);
1441                 return ERR_PTR(-ESTALE);
1442         }
1443
1444         return inode;
1445 }
1446
1447 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1448                                         int fh_len, int fh_type)
1449 {
1450         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1451                                     ext4_nfs_get_inode);
1452 }
1453
1454 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1455                                         int fh_len, int fh_type)
1456 {
1457         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1458                                     ext4_nfs_get_inode);
1459 }
1460
1461 static int ext4_nfs_commit_metadata(struct inode *inode)
1462 {
1463         struct writeback_control wbc = {
1464                 .sync_mode = WB_SYNC_ALL
1465         };
1466
1467         trace_ext4_nfs_commit_metadata(inode);
1468         return ext4_write_inode(inode, &wbc);
1469 }
1470
1471 /*
1472  * Try to release metadata pages (indirect blocks, directories) which are
1473  * mapped via the block device.  Since these pages could have journal heads
1474  * which would prevent try_to_free_buffers() from freeing them, we must use
1475  * jbd2 layer's try_to_free_buffers() function to release them.
1476  */
1477 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1478                                  gfp_t wait)
1479 {
1480         journal_t *journal = EXT4_SB(sb)->s_journal;
1481
1482         WARN_ON(PageChecked(page));
1483         if (!page_has_buffers(page))
1484                 return 0;
1485         if (journal)
1486                 return jbd2_journal_try_to_free_buffers(journal, page);
1487
1488         return try_to_free_buffers(page);
1489 }
1490
1491 #ifdef CONFIG_FS_ENCRYPTION
1492 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1493 {
1494         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1495                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1496 }
1497
1498 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1499                                                         void *fs_data)
1500 {
1501         handle_t *handle = fs_data;
1502         int res, res2, credits, retries = 0;
1503
1504         /*
1505          * Encrypting the root directory is not allowed because e2fsck expects
1506          * lost+found to exist and be unencrypted, and encrypting the root
1507          * directory would imply encrypting the lost+found directory as well as
1508          * the filename "lost+found" itself.
1509          */
1510         if (inode->i_ino == EXT4_ROOT_INO)
1511                 return -EPERM;
1512
1513         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1514                 return -EINVAL;
1515
1516         if (ext4_test_inode_flag(inode, EXT4_INODE_DAX))
1517                 return -EOPNOTSUPP;
1518
1519         res = ext4_convert_inline_data(inode);
1520         if (res)
1521                 return res;
1522
1523         /*
1524          * If a journal handle was specified, then the encryption context is
1525          * being set on a new inode via inheritance and is part of a larger
1526          * transaction to create the inode.  Otherwise the encryption context is
1527          * being set on an existing inode in its own transaction.  Only in the
1528          * latter case should the "retry on ENOSPC" logic be used.
1529          */
1530
1531         if (handle) {
1532                 res = ext4_xattr_set_handle(handle, inode,
1533                                             EXT4_XATTR_INDEX_ENCRYPTION,
1534                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1535                                             ctx, len, 0);
1536                 if (!res) {
1537                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1538                         ext4_clear_inode_state(inode,
1539                                         EXT4_STATE_MAY_INLINE_DATA);
1540                         /*
1541                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1542                          * S_DAX may be disabled
1543                          */
1544                         ext4_set_inode_flags(inode, false);
1545                 }
1546                 return res;
1547         }
1548
1549         res = dquot_initialize(inode);
1550         if (res)
1551                 return res;
1552 retry:
1553         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1554                                      &credits);
1555         if (res)
1556                 return res;
1557
1558         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1559         if (IS_ERR(handle))
1560                 return PTR_ERR(handle);
1561
1562         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1563                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1564                                     ctx, len, 0);
1565         if (!res) {
1566                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1567                 /*
1568                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1569                  * S_DAX may be disabled
1570                  */
1571                 ext4_set_inode_flags(inode, false);
1572                 res = ext4_mark_inode_dirty(handle, inode);
1573                 if (res)
1574                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1575         }
1576         res2 = ext4_journal_stop(handle);
1577
1578         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1579                 goto retry;
1580         if (!res)
1581                 res = res2;
1582         return res;
1583 }
1584
1585 static const union fscrypt_policy *ext4_get_dummy_policy(struct super_block *sb)
1586 {
1587         return EXT4_SB(sb)->s_dummy_enc_policy.policy;
1588 }
1589
1590 static bool ext4_has_stable_inodes(struct super_block *sb)
1591 {
1592         return ext4_has_feature_stable_inodes(sb);
1593 }
1594
1595 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1596                                        int *ino_bits_ret, int *lblk_bits_ret)
1597 {
1598         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1599         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1600 }
1601
1602 static const struct fscrypt_operations ext4_cryptops = {
1603         .key_prefix             = "ext4:",
1604         .get_context            = ext4_get_context,
1605         .set_context            = ext4_set_context,
1606         .get_dummy_policy       = ext4_get_dummy_policy,
1607         .empty_dir              = ext4_empty_dir,
1608         .max_namelen            = EXT4_NAME_LEN,
1609         .has_stable_inodes      = ext4_has_stable_inodes,
1610         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1611 };
1612 #endif
1613
1614 #ifdef CONFIG_QUOTA
1615 static const char * const quotatypes[] = INITQFNAMES;
1616 #define QTYPE2NAME(t) (quotatypes[t])
1617
1618 static int ext4_write_dquot(struct dquot *dquot);
1619 static int ext4_acquire_dquot(struct dquot *dquot);
1620 static int ext4_release_dquot(struct dquot *dquot);
1621 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1622 static int ext4_write_info(struct super_block *sb, int type);
1623 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1624                          const struct path *path);
1625 static int ext4_quota_on_mount(struct super_block *sb, int type);
1626 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1627                                size_t len, loff_t off);
1628 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1629                                 const char *data, size_t len, loff_t off);
1630 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1631                              unsigned int flags);
1632 static int ext4_enable_quotas(struct super_block *sb);
1633
1634 static struct dquot **ext4_get_dquots(struct inode *inode)
1635 {
1636         return EXT4_I(inode)->i_dquot;
1637 }
1638
1639 static const struct dquot_operations ext4_quota_operations = {
1640         .get_reserved_space     = ext4_get_reserved_space,
1641         .write_dquot            = ext4_write_dquot,
1642         .acquire_dquot          = ext4_acquire_dquot,
1643         .release_dquot          = ext4_release_dquot,
1644         .mark_dirty             = ext4_mark_dquot_dirty,
1645         .write_info             = ext4_write_info,
1646         .alloc_dquot            = dquot_alloc,
1647         .destroy_dquot          = dquot_destroy,
1648         .get_projid             = ext4_get_projid,
1649         .get_inode_usage        = ext4_get_inode_usage,
1650         .get_next_id            = dquot_get_next_id,
1651 };
1652
1653 static const struct quotactl_ops ext4_qctl_operations = {
1654         .quota_on       = ext4_quota_on,
1655         .quota_off      = ext4_quota_off,
1656         .quota_sync     = dquot_quota_sync,
1657         .get_state      = dquot_get_state,
1658         .set_info       = dquot_set_dqinfo,
1659         .get_dqblk      = dquot_get_dqblk,
1660         .set_dqblk      = dquot_set_dqblk,
1661         .get_nextdqblk  = dquot_get_next_dqblk,
1662 };
1663 #endif
1664
1665 static const struct super_operations ext4_sops = {
1666         .alloc_inode    = ext4_alloc_inode,
1667         .free_inode     = ext4_free_in_core_inode,
1668         .destroy_inode  = ext4_destroy_inode,
1669         .write_inode    = ext4_write_inode,
1670         .dirty_inode    = ext4_dirty_inode,
1671         .drop_inode     = ext4_drop_inode,
1672         .evict_inode    = ext4_evict_inode,
1673         .put_super      = ext4_put_super,
1674         .sync_fs        = ext4_sync_fs,
1675         .freeze_fs      = ext4_freeze,
1676         .unfreeze_fs    = ext4_unfreeze,
1677         .statfs         = ext4_statfs,
1678         .remount_fs     = ext4_remount,
1679         .show_options   = ext4_show_options,
1680 #ifdef CONFIG_QUOTA
1681         .quota_read     = ext4_quota_read,
1682         .quota_write    = ext4_quota_write,
1683         .get_dquots     = ext4_get_dquots,
1684 #endif
1685         .bdev_try_to_free_page = bdev_try_to_free_page,
1686 };
1687
1688 static const struct export_operations ext4_export_ops = {
1689         .fh_to_dentry = ext4_fh_to_dentry,
1690         .fh_to_parent = ext4_fh_to_parent,
1691         .get_parent = ext4_get_parent,
1692         .commit_metadata = ext4_nfs_commit_metadata,
1693 };
1694
1695 enum {
1696         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1697         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1698         Opt_nouid32, Opt_debug, Opt_removed,
1699         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1700         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1701         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1702         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1703         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1704         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1705         Opt_inlinecrypt,
1706         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1707         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1708         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1709         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
1710         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1711         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1712         Opt_nowarn_on_error, Opt_mblk_io_submit,
1713         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1714         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1715         Opt_inode_readahead_blks, Opt_journal_ioprio,
1716         Opt_dioread_nolock, Opt_dioread_lock,
1717         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1718         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1719         Opt_prefetch_block_bitmaps, Opt_no_fc,
1720 #ifdef CONFIG_EXT4_DEBUG
1721         Opt_fc_debug_max_replay,
1722 #endif
1723         Opt_fc_debug_force
1724 };
1725
1726 static const match_table_t tokens = {
1727         {Opt_bsd_df, "bsddf"},
1728         {Opt_minix_df, "minixdf"},
1729         {Opt_grpid, "grpid"},
1730         {Opt_grpid, "bsdgroups"},
1731         {Opt_nogrpid, "nogrpid"},
1732         {Opt_nogrpid, "sysvgroups"},
1733         {Opt_resgid, "resgid=%u"},
1734         {Opt_resuid, "resuid=%u"},
1735         {Opt_sb, "sb=%u"},
1736         {Opt_err_cont, "errors=continue"},
1737         {Opt_err_panic, "errors=panic"},
1738         {Opt_err_ro, "errors=remount-ro"},
1739         {Opt_nouid32, "nouid32"},
1740         {Opt_debug, "debug"},
1741         {Opt_removed, "oldalloc"},
1742         {Opt_removed, "orlov"},
1743         {Opt_user_xattr, "user_xattr"},
1744         {Opt_nouser_xattr, "nouser_xattr"},
1745         {Opt_acl, "acl"},
1746         {Opt_noacl, "noacl"},
1747         {Opt_noload, "norecovery"},
1748         {Opt_noload, "noload"},
1749         {Opt_removed, "nobh"},
1750         {Opt_removed, "bh"},
1751         {Opt_commit, "commit=%u"},
1752         {Opt_min_batch_time, "min_batch_time=%u"},
1753         {Opt_max_batch_time, "max_batch_time=%u"},
1754         {Opt_journal_dev, "journal_dev=%u"},
1755         {Opt_journal_path, "journal_path=%s"},
1756         {Opt_journal_checksum, "journal_checksum"},
1757         {Opt_nojournal_checksum, "nojournal_checksum"},
1758         {Opt_journal_async_commit, "journal_async_commit"},
1759         {Opt_abort, "abort"},
1760         {Opt_data_journal, "data=journal"},
1761         {Opt_data_ordered, "data=ordered"},
1762         {Opt_data_writeback, "data=writeback"},
1763         {Opt_data_err_abort, "data_err=abort"},
1764         {Opt_data_err_ignore, "data_err=ignore"},
1765         {Opt_offusrjquota, "usrjquota="},
1766         {Opt_usrjquota, "usrjquota=%s"},
1767         {Opt_offgrpjquota, "grpjquota="},
1768         {Opt_grpjquota, "grpjquota=%s"},
1769         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1770         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1771         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1772         {Opt_grpquota, "grpquota"},
1773         {Opt_noquota, "noquota"},
1774         {Opt_quota, "quota"},
1775         {Opt_usrquota, "usrquota"},
1776         {Opt_prjquota, "prjquota"},
1777         {Opt_barrier, "barrier=%u"},
1778         {Opt_barrier, "barrier"},
1779         {Opt_nobarrier, "nobarrier"},
1780         {Opt_i_version, "i_version"},
1781         {Opt_dax, "dax"},
1782         {Opt_dax_always, "dax=always"},
1783         {Opt_dax_inode, "dax=inode"},
1784         {Opt_dax_never, "dax=never"},
1785         {Opt_stripe, "stripe=%u"},
1786         {Opt_delalloc, "delalloc"},
1787         {Opt_warn_on_error, "warn_on_error"},
1788         {Opt_nowarn_on_error, "nowarn_on_error"},
1789         {Opt_lazytime, "lazytime"},
1790         {Opt_nolazytime, "nolazytime"},
1791         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1792         {Opt_nodelalloc, "nodelalloc"},
1793         {Opt_removed, "mblk_io_submit"},
1794         {Opt_removed, "nomblk_io_submit"},
1795         {Opt_block_validity, "block_validity"},
1796         {Opt_noblock_validity, "noblock_validity"},
1797         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1798         {Opt_journal_ioprio, "journal_ioprio=%u"},
1799         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1800         {Opt_auto_da_alloc, "auto_da_alloc"},
1801         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1802         {Opt_dioread_nolock, "dioread_nolock"},
1803         {Opt_dioread_lock, "nodioread_nolock"},
1804         {Opt_dioread_lock, "dioread_lock"},
1805         {Opt_discard, "discard"},
1806         {Opt_nodiscard, "nodiscard"},
1807         {Opt_init_itable, "init_itable=%u"},
1808         {Opt_init_itable, "init_itable"},
1809         {Opt_noinit_itable, "noinit_itable"},
1810         {Opt_no_fc, "no_fc"},
1811         {Opt_fc_debug_force, "fc_debug_force"},
1812 #ifdef CONFIG_EXT4_DEBUG
1813         {Opt_fc_debug_max_replay, "fc_debug_max_replay=%u"},
1814 #endif
1815         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1816         {Opt_test_dummy_encryption, "test_dummy_encryption=%s"},
1817         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1818         {Opt_inlinecrypt, "inlinecrypt"},
1819         {Opt_nombcache, "nombcache"},
1820         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1821         {Opt_prefetch_block_bitmaps, "prefetch_block_bitmaps"},
1822         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1823         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1824         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1825         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1826         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1827         {Opt_err, NULL},
1828 };
1829
1830 static ext4_fsblk_t get_sb_block(void **data)
1831 {
1832         ext4_fsblk_t    sb_block;
1833         char            *options = (char *) *data;
1834
1835         if (!options || strncmp(options, "sb=", 3) != 0)
1836                 return 1;       /* Default location */
1837
1838         options += 3;
1839         /* TODO: use simple_strtoll with >32bit ext4 */
1840         sb_block = simple_strtoul(options, &options, 0);
1841         if (*options && *options != ',') {
1842                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1843                        (char *) *data);
1844                 return 1;
1845         }
1846         if (*options == ',')
1847                 options++;
1848         *data = (void *) options;
1849
1850         return sb_block;
1851 }
1852
1853 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1854 static const char deprecated_msg[] =
1855         "Mount option \"%s\" will be removed by %s\n"
1856         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1857
1858 #ifdef CONFIG_QUOTA
1859 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1860 {
1861         struct ext4_sb_info *sbi = EXT4_SB(sb);
1862         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1863         int ret = -1;
1864
1865         if (sb_any_quota_loaded(sb) && !old_qname) {
1866                 ext4_msg(sb, KERN_ERR,
1867                         "Cannot change journaled "
1868                         "quota options when quota turned on");
1869                 return -1;
1870         }
1871         if (ext4_has_feature_quota(sb)) {
1872                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1873                          "ignored when QUOTA feature is enabled");
1874                 return 1;
1875         }
1876         qname = match_strdup(args);
1877         if (!qname) {
1878                 ext4_msg(sb, KERN_ERR,
1879                         "Not enough memory for storing quotafile name");
1880                 return -1;
1881         }
1882         if (old_qname) {
1883                 if (strcmp(old_qname, qname) == 0)
1884                         ret = 1;
1885                 else
1886                         ext4_msg(sb, KERN_ERR,
1887                                  "%s quota file already specified",
1888                                  QTYPE2NAME(qtype));
1889                 goto errout;
1890         }
1891         if (strchr(qname, '/')) {
1892                 ext4_msg(sb, KERN_ERR,
1893                         "quotafile must be on filesystem root");
1894                 goto errout;
1895         }
1896         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1897         set_opt(sb, QUOTA);
1898         return 1;
1899 errout:
1900         kfree(qname);
1901         return ret;
1902 }
1903
1904 static int clear_qf_name(struct super_block *sb, int qtype)
1905 {
1906
1907         struct ext4_sb_info *sbi = EXT4_SB(sb);
1908         char *old_qname = get_qf_name(sb, sbi, qtype);
1909
1910         if (sb_any_quota_loaded(sb) && old_qname) {
1911                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1912                         " when quota turned on");
1913                 return -1;
1914         }
1915         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1916         synchronize_rcu();
1917         kfree(old_qname);
1918         return 1;
1919 }
1920 #endif
1921
1922 #define MOPT_SET        0x0001
1923 #define MOPT_CLEAR      0x0002
1924 #define MOPT_NOSUPPORT  0x0004
1925 #define MOPT_EXPLICIT   0x0008
1926 #define MOPT_CLEAR_ERR  0x0010
1927 #define MOPT_GTE0       0x0020
1928 #ifdef CONFIG_QUOTA
1929 #define MOPT_Q          0
1930 #define MOPT_QFMT       0x0040
1931 #else
1932 #define MOPT_Q          MOPT_NOSUPPORT
1933 #define MOPT_QFMT       MOPT_NOSUPPORT
1934 #endif
1935 #define MOPT_DATAJ      0x0080
1936 #define MOPT_NO_EXT2    0x0100
1937 #define MOPT_NO_EXT3    0x0200
1938 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1939 #define MOPT_STRING     0x0400
1940 #define MOPT_SKIP       0x0800
1941 #define MOPT_2          0x1000
1942
1943 static const struct mount_opts {
1944         int     token;
1945         int     mount_opt;
1946         int     flags;
1947 } ext4_mount_opts[] = {
1948         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1949         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1950         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1951         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1952         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1953         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1954         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1955          MOPT_EXT4_ONLY | MOPT_SET},
1956         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1957          MOPT_EXT4_ONLY | MOPT_CLEAR},
1958         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1959         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1960         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1961          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1962         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1963          MOPT_EXT4_ONLY | MOPT_CLEAR},
1964         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1965         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1966         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1967          MOPT_EXT4_ONLY | MOPT_CLEAR},
1968         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1969          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1970         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1971                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1972          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1973         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1974         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1975         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1976         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1977         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1978          MOPT_NO_EXT2},
1979         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1980          MOPT_NO_EXT2},
1981         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1982         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1983         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1984         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1985         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1986         {Opt_commit, 0, MOPT_GTE0},
1987         {Opt_max_batch_time, 0, MOPT_GTE0},
1988         {Opt_min_batch_time, 0, MOPT_GTE0},
1989         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1990         {Opt_init_itable, 0, MOPT_GTE0},
1991         {Opt_dax, EXT4_MOUNT_DAX_ALWAYS, MOPT_SET | MOPT_SKIP},
1992         {Opt_dax_always, EXT4_MOUNT_DAX_ALWAYS,
1993                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1994         {Opt_dax_inode, EXT4_MOUNT2_DAX_INODE,
1995                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1996         {Opt_dax_never, EXT4_MOUNT2_DAX_NEVER,
1997                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1998         {Opt_stripe, 0, MOPT_GTE0},
1999         {Opt_resuid, 0, MOPT_GTE0},
2000         {Opt_resgid, 0, MOPT_GTE0},
2001         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
2002         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
2003         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
2004         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
2005         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
2006         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
2007          MOPT_NO_EXT2 | MOPT_DATAJ},
2008         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
2009         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
2010 #ifdef CONFIG_EXT4_FS_POSIX_ACL
2011         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
2012         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
2013 #else
2014         {Opt_acl, 0, MOPT_NOSUPPORT},
2015         {Opt_noacl, 0, MOPT_NOSUPPORT},
2016 #endif
2017         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
2018         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
2019         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
2020         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
2021         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
2022                                                         MOPT_SET | MOPT_Q},
2023         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
2024                                                         MOPT_SET | MOPT_Q},
2025         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
2026                                                         MOPT_SET | MOPT_Q},
2027         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2028                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
2029                                                         MOPT_CLEAR | MOPT_Q},
2030         {Opt_usrjquota, 0, MOPT_Q},
2031         {Opt_grpjquota, 0, MOPT_Q},
2032         {Opt_offusrjquota, 0, MOPT_Q},
2033         {Opt_offgrpjquota, 0, MOPT_Q},
2034         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
2035         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
2036         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
2037         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
2038         {Opt_test_dummy_encryption, 0, MOPT_STRING},
2039         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
2040         {Opt_prefetch_block_bitmaps, EXT4_MOUNT_PREFETCH_BLOCK_BITMAPS,
2041          MOPT_SET},
2042         {Opt_no_fc, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
2043          MOPT_CLEAR | MOPT_2 | MOPT_EXT4_ONLY},
2044         {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
2045          MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
2046 #ifdef CONFIG_EXT4_DEBUG
2047         {Opt_fc_debug_max_replay, 0, MOPT_GTE0},
2048 #endif
2049         {Opt_err, 0, 0}
2050 };
2051
2052 #ifdef CONFIG_UNICODE
2053 static const struct ext4_sb_encodings {
2054         __u16 magic;
2055         char *name;
2056         char *version;
2057 } ext4_sb_encoding_map[] = {
2058         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
2059 };
2060
2061 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
2062                                  const struct ext4_sb_encodings **encoding,
2063                                  __u16 *flags)
2064 {
2065         __u16 magic = le16_to_cpu(es->s_encoding);
2066         int i;
2067
2068         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
2069                 if (magic == ext4_sb_encoding_map[i].magic)
2070                         break;
2071
2072         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
2073                 return -EINVAL;
2074
2075         *encoding = &ext4_sb_encoding_map[i];
2076         *flags = le16_to_cpu(es->s_encoding_flags);
2077
2078         return 0;
2079 }
2080 #endif
2081
2082 static int ext4_set_test_dummy_encryption(struct super_block *sb,
2083                                           const char *opt,
2084                                           const substring_t *arg,
2085                                           bool is_remount)
2086 {
2087 #ifdef CONFIG_FS_ENCRYPTION
2088         struct ext4_sb_info *sbi = EXT4_SB(sb);
2089         int err;
2090
2091         /*
2092          * This mount option is just for testing, and it's not worthwhile to
2093          * implement the extra complexity (e.g. RCU protection) that would be
2094          * needed to allow it to be set or changed during remount.  We do allow
2095          * it to be specified during remount, but only if there is no change.
2096          */
2097         if (is_remount && !sbi->s_dummy_enc_policy.policy) {
2098                 ext4_msg(sb, KERN_WARNING,
2099                          "Can't set test_dummy_encryption on remount");
2100                 return -1;
2101         }
2102         err = fscrypt_set_test_dummy_encryption(sb, arg->from,
2103                                                 &sbi->s_dummy_enc_policy);
2104         if (err) {
2105                 if (err == -EEXIST)
2106                         ext4_msg(sb, KERN_WARNING,
2107                                  "Can't change test_dummy_encryption on remount");
2108                 else if (err == -EINVAL)
2109                         ext4_msg(sb, KERN_WARNING,
2110                                  "Value of option \"%s\" is unrecognized", opt);
2111                 else
2112                         ext4_msg(sb, KERN_WARNING,
2113                                  "Error processing option \"%s\" [%d]",
2114                                  opt, err);
2115                 return -1;
2116         }
2117         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2118 #else
2119         ext4_msg(sb, KERN_WARNING,
2120                  "Test dummy encryption mount option ignored");
2121 #endif
2122         return 1;
2123 }
2124
2125 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
2126                             substring_t *args, unsigned long *journal_devnum,
2127                             unsigned int *journal_ioprio, int is_remount)
2128 {
2129         struct ext4_sb_info *sbi = EXT4_SB(sb);
2130         const struct mount_opts *m;
2131         kuid_t uid;
2132         kgid_t gid;
2133         int arg = 0;
2134
2135 #ifdef CONFIG_QUOTA
2136         if (token == Opt_usrjquota)
2137                 return set_qf_name(sb, USRQUOTA, &args[0]);
2138         else if (token == Opt_grpjquota)
2139                 return set_qf_name(sb, GRPQUOTA, &args[0]);
2140         else if (token == Opt_offusrjquota)
2141                 return clear_qf_name(sb, USRQUOTA);
2142         else if (token == Opt_offgrpjquota)
2143                 return clear_qf_name(sb, GRPQUOTA);
2144 #endif
2145         switch (token) {
2146         case Opt_noacl:
2147         case Opt_nouser_xattr:
2148                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
2149                 break;
2150         case Opt_sb:
2151                 return 1;       /* handled by get_sb_block() */
2152         case Opt_removed:
2153                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
2154                 return 1;
2155         case Opt_abort:
2156                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
2157                 return 1;
2158         case Opt_i_version:
2159                 sb->s_flags |= SB_I_VERSION;
2160                 return 1;
2161         case Opt_lazytime:
2162                 sb->s_flags |= SB_LAZYTIME;
2163                 return 1;
2164         case Opt_nolazytime:
2165                 sb->s_flags &= ~SB_LAZYTIME;
2166                 return 1;
2167         case Opt_inlinecrypt:
2168 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2169                 sb->s_flags |= SB_INLINECRYPT;
2170 #else
2171                 ext4_msg(sb, KERN_ERR, "inline encryption not supported");
2172 #endif
2173                 return 1;
2174         }
2175
2176         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2177                 if (token == m->token)
2178                         break;
2179
2180         if (m->token == Opt_err) {
2181                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
2182                          "or missing value", opt);
2183                 return -1;
2184         }
2185
2186         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2187                 ext4_msg(sb, KERN_ERR,
2188                          "Mount option \"%s\" incompatible with ext2", opt);
2189                 return -1;
2190         }
2191         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2192                 ext4_msg(sb, KERN_ERR,
2193                          "Mount option \"%s\" incompatible with ext3", opt);
2194                 return -1;
2195         }
2196
2197         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
2198                 return -1;
2199         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
2200                 return -1;
2201         if (m->flags & MOPT_EXPLICIT) {
2202                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2203                         set_opt2(sb, EXPLICIT_DELALLOC);
2204                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2205                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
2206                 } else
2207                         return -1;
2208         }
2209         if (m->flags & MOPT_CLEAR_ERR)
2210                 clear_opt(sb, ERRORS_MASK);
2211         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
2212                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
2213                          "options when quota turned on");
2214                 return -1;
2215         }
2216
2217         if (m->flags & MOPT_NOSUPPORT) {
2218                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
2219         } else if (token == Opt_commit) {
2220                 if (arg == 0)
2221                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
2222                 else if (arg > INT_MAX / HZ) {
2223                         ext4_msg(sb, KERN_ERR,
2224                                  "Invalid commit interval %d, "
2225                                  "must be smaller than %d",
2226                                  arg, INT_MAX / HZ);
2227                         return -1;
2228                 }
2229                 sbi->s_commit_interval = HZ * arg;
2230         } else if (token == Opt_debug_want_extra_isize) {
2231                 if ((arg & 1) ||
2232                     (arg < 4) ||
2233                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
2234                         ext4_msg(sb, KERN_ERR,
2235                                  "Invalid want_extra_isize %d", arg);
2236                         return -1;
2237                 }
2238                 sbi->s_want_extra_isize = arg;
2239         } else if (token == Opt_max_batch_time) {
2240                 sbi->s_max_batch_time = arg;
2241         } else if (token == Opt_min_batch_time) {
2242                 sbi->s_min_batch_time = arg;
2243         } else if (token == Opt_inode_readahead_blks) {
2244                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
2245                         ext4_msg(sb, KERN_ERR,
2246                                  "EXT4-fs: inode_readahead_blks must be "
2247                                  "0 or a power of 2 smaller than 2^31");
2248                         return -1;
2249                 }
2250                 sbi->s_inode_readahead_blks = arg;
2251         } else if (token == Opt_init_itable) {
2252                 set_opt(sb, INIT_INODE_TABLE);
2253                 if (!args->from)
2254                         arg = EXT4_DEF_LI_WAIT_MULT;
2255                 sbi->s_li_wait_mult = arg;
2256         } else if (token == Opt_max_dir_size_kb) {
2257                 sbi->s_max_dir_size_kb = arg;
2258 #ifdef CONFIG_EXT4_DEBUG
2259         } else if (token == Opt_fc_debug_max_replay) {
2260                 sbi->s_fc_debug_max_replay = arg;
2261 #endif
2262         } else if (token == Opt_stripe) {
2263                 sbi->s_stripe = arg;
2264         } else if (token == Opt_resuid) {
2265                 uid = make_kuid(current_user_ns(), arg);
2266                 if (!uid_valid(uid)) {
2267                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
2268                         return -1;
2269                 }
2270                 sbi->s_resuid = uid;
2271         } else if (token == Opt_resgid) {
2272                 gid = make_kgid(current_user_ns(), arg);
2273                 if (!gid_valid(gid)) {
2274                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
2275                         return -1;
2276                 }
2277                 sbi->s_resgid = gid;
2278         } else if (token == Opt_journal_dev) {
2279                 if (is_remount) {
2280                         ext4_msg(sb, KERN_ERR,
2281                                  "Cannot specify journal on remount");
2282                         return -1;
2283                 }
2284                 *journal_devnum = arg;
2285         } else if (token == Opt_journal_path) {
2286                 char *journal_path;
2287                 struct inode *journal_inode;
2288                 struct path path;
2289                 int error;
2290
2291                 if (is_remount) {
2292                         ext4_msg(sb, KERN_ERR,
2293                                  "Cannot specify journal on remount");
2294                         return -1;
2295                 }
2296                 journal_path = match_strdup(&args[0]);
2297                 if (!journal_path) {
2298                         ext4_msg(sb, KERN_ERR, "error: could not dup "
2299                                 "journal device string");
2300                         return -1;
2301                 }
2302
2303                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2304                 if (error) {
2305                         ext4_msg(sb, KERN_ERR, "error: could not find "
2306                                 "journal device path: error %d", error);
2307                         kfree(journal_path);
2308                         return -1;
2309                 }
2310
2311                 journal_inode = d_inode(path.dentry);
2312                 if (!S_ISBLK(journal_inode->i_mode)) {
2313                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
2314                                 "is not a block device", journal_path);
2315                         path_put(&path);
2316                         kfree(journal_path);
2317                         return -1;
2318                 }
2319
2320                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
2321                 path_put(&path);
2322                 kfree(journal_path);
2323         } else if (token == Opt_journal_ioprio) {
2324                 if (arg > 7) {
2325                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2326                                  " (must be 0-7)");
2327                         return -1;
2328                 }
2329                 *journal_ioprio =
2330                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2331         } else if (token == Opt_test_dummy_encryption) {
2332                 return ext4_set_test_dummy_encryption(sb, opt, &args[0],
2333                                                       is_remount);
2334         } else if (m->flags & MOPT_DATAJ) {
2335                 if (is_remount) {
2336                         if (!sbi->s_journal)
2337                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2338                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2339                                 ext4_msg(sb, KERN_ERR,
2340                                          "Cannot change data mode on remount");
2341                                 return -1;
2342                         }
2343                 } else {
2344                         clear_opt(sb, DATA_FLAGS);
2345                         sbi->s_mount_opt |= m->mount_opt;
2346                 }
2347 #ifdef CONFIG_QUOTA
2348         } else if (m->flags & MOPT_QFMT) {
2349                 if (sb_any_quota_loaded(sb) &&
2350                     sbi->s_jquota_fmt != m->mount_opt) {
2351                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2352                                  "quota options when quota turned on");
2353                         return -1;
2354                 }
2355                 if (ext4_has_feature_quota(sb)) {
2356                         ext4_msg(sb, KERN_INFO,
2357                                  "Quota format mount options ignored "
2358                                  "when QUOTA feature is enabled");
2359                         return 1;
2360                 }
2361                 sbi->s_jquota_fmt = m->mount_opt;
2362 #endif
2363         } else if (token == Opt_dax || token == Opt_dax_always ||
2364                    token == Opt_dax_inode || token == Opt_dax_never) {
2365 #ifdef CONFIG_FS_DAX
2366                 switch (token) {
2367                 case Opt_dax:
2368                 case Opt_dax_always:
2369                         if (is_remount &&
2370                             (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2371                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2372                         fail_dax_change_remount:
2373                                 ext4_msg(sb, KERN_ERR, "can't change "
2374                                          "dax mount option while remounting");
2375                                 return -1;
2376                         }
2377                         if (is_remount &&
2378                             (test_opt(sb, DATA_FLAGS) ==
2379                              EXT4_MOUNT_JOURNAL_DATA)) {
2380                                     ext4_msg(sb, KERN_ERR, "can't mount with "
2381                                              "both data=journal and dax");
2382                                     return -1;
2383                         }
2384                         ext4_msg(sb, KERN_WARNING,
2385                                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2386                         sbi->s_mount_opt |= EXT4_MOUNT_DAX_ALWAYS;
2387                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2388                         break;
2389                 case Opt_dax_never:
2390                         if (is_remount &&
2391                             (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2392                              (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS)))
2393                                 goto fail_dax_change_remount;
2394                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2395                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2396                         break;
2397                 case Opt_dax_inode:
2398                         if (is_remount &&
2399                             ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2400                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2401                              !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE)))
2402                                 goto fail_dax_change_remount;
2403                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2404                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2405                         /* Strictly for printing options */
2406                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_INODE;
2407                         break;
2408                 }
2409 #else
2410                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2411                 sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2412                 sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2413                 return -1;
2414 #endif
2415         } else if (token == Opt_data_err_abort) {
2416                 sbi->s_mount_opt |= m->mount_opt;
2417         } else if (token == Opt_data_err_ignore) {
2418                 sbi->s_mount_opt &= ~m->mount_opt;
2419         } else {
2420                 if (!args->from)
2421                         arg = 1;
2422                 if (m->flags & MOPT_CLEAR)
2423                         arg = !arg;
2424                 else if (unlikely(!(m->flags & MOPT_SET))) {
2425                         ext4_msg(sb, KERN_WARNING,
2426                                  "buggy handling of option %s", opt);
2427                         WARN_ON(1);
2428                         return -1;
2429                 }
2430                 if (m->flags & MOPT_2) {
2431                         if (arg != 0)
2432                                 sbi->s_mount_opt2 |= m->mount_opt;
2433                         else
2434                                 sbi->s_mount_opt2 &= ~m->mount_opt;
2435                 } else {
2436                         if (arg != 0)
2437                                 sbi->s_mount_opt |= m->mount_opt;
2438                         else
2439                                 sbi->s_mount_opt &= ~m->mount_opt;
2440                 }
2441         }
2442         return 1;
2443 }
2444
2445 static int parse_options(char *options, struct super_block *sb,
2446                          unsigned long *journal_devnum,
2447                          unsigned int *journal_ioprio,
2448                          int is_remount)
2449 {
2450         struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2451         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2452         substring_t args[MAX_OPT_ARGS];
2453         int token;
2454
2455         if (!options)
2456                 return 1;
2457
2458         while ((p = strsep(&options, ",")) != NULL) {
2459                 if (!*p)
2460                         continue;
2461                 /*
2462                  * Initialize args struct so we know whether arg was
2463                  * found; some options take optional arguments.
2464                  */
2465                 args[0].to = args[0].from = NULL;
2466                 token = match_token(p, tokens, args);
2467                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2468                                      journal_ioprio, is_remount) < 0)
2469                         return 0;
2470         }
2471 #ifdef CONFIG_QUOTA
2472         /*
2473          * We do the test below only for project quotas. 'usrquota' and
2474          * 'grpquota' mount options are allowed even without quota feature
2475          * to support legacy quotas in quota files.
2476          */
2477         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2478                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2479                          "Cannot enable project quota enforcement.");
2480                 return 0;
2481         }
2482         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2483         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2484         if (usr_qf_name || grp_qf_name) {
2485                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2486                         clear_opt(sb, USRQUOTA);
2487
2488                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2489                         clear_opt(sb, GRPQUOTA);
2490
2491                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2492                         ext4_msg(sb, KERN_ERR, "old and new quota "
2493                                         "format mixing");
2494                         return 0;
2495                 }
2496
2497                 if (!sbi->s_jquota_fmt) {
2498                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2499                                         "not specified");
2500                         return 0;
2501                 }
2502         }
2503 #endif
2504         if (test_opt(sb, DIOREAD_NOLOCK)) {
2505                 int blocksize =
2506                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2507                 if (blocksize < PAGE_SIZE)
2508                         ext4_msg(sb, KERN_WARNING, "Warning: mounting with an "
2509                                  "experimental mount option 'dioread_nolock' "
2510                                  "for blocksize < PAGE_SIZE");
2511         }
2512         return 1;
2513 }
2514
2515 static inline void ext4_show_quota_options(struct seq_file *seq,
2516                                            struct super_block *sb)
2517 {
2518 #if defined(CONFIG_QUOTA)
2519         struct ext4_sb_info *sbi = EXT4_SB(sb);
2520         char *usr_qf_name, *grp_qf_name;
2521
2522         if (sbi->s_jquota_fmt) {
2523                 char *fmtname = "";
2524
2525                 switch (sbi->s_jquota_fmt) {
2526                 case QFMT_VFS_OLD:
2527                         fmtname = "vfsold";
2528                         break;
2529                 case QFMT_VFS_V0:
2530                         fmtname = "vfsv0";
2531                         break;
2532                 case QFMT_VFS_V1:
2533                         fmtname = "vfsv1";
2534                         break;
2535                 }
2536                 seq_printf(seq, ",jqfmt=%s", fmtname);
2537         }
2538
2539         rcu_read_lock();
2540         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2541         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2542         if (usr_qf_name)
2543                 seq_show_option(seq, "usrjquota", usr_qf_name);
2544         if (grp_qf_name)
2545                 seq_show_option(seq, "grpjquota", grp_qf_name);
2546         rcu_read_unlock();
2547 #endif
2548 }
2549
2550 static const char *token2str(int token)
2551 {
2552         const struct match_token *t;
2553
2554         for (t = tokens; t->token != Opt_err; t++)
2555                 if (t->token == token && !strchr(t->pattern, '='))
2556                         break;
2557         return t->pattern;
2558 }
2559
2560 /*
2561  * Show an option if
2562  *  - it's set to a non-default value OR
2563  *  - if the per-sb default is different from the global default
2564  */
2565 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2566                               int nodefs)
2567 {
2568         struct ext4_sb_info *sbi = EXT4_SB(sb);
2569         struct ext4_super_block *es = sbi->s_es;
2570         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2571         const struct mount_opts *m;
2572         char sep = nodefs ? '\n' : ',';
2573
2574 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2575 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2576
2577         if (sbi->s_sb_block != 1)
2578                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2579
2580         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2581                 int want_set = m->flags & MOPT_SET;
2582                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2583                     (m->flags & MOPT_CLEAR_ERR) || m->flags & MOPT_SKIP)
2584                         continue;
2585                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2586                         continue; /* skip if same as the default */
2587                 if ((want_set &&
2588                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2589                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2590                         continue; /* select Opt_noFoo vs Opt_Foo */
2591                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2592         }
2593
2594         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2595             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2596                 SEQ_OPTS_PRINT("resuid=%u",
2597                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2598         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2599             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2600                 SEQ_OPTS_PRINT("resgid=%u",
2601                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2602         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2603         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2604                 SEQ_OPTS_PUTS("errors=remount-ro");
2605         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2606                 SEQ_OPTS_PUTS("errors=continue");
2607         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2608                 SEQ_OPTS_PUTS("errors=panic");
2609         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2610                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2611         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2612                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2613         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2614                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2615         if (sb->s_flags & SB_I_VERSION)
2616                 SEQ_OPTS_PUTS("i_version");
2617         if (nodefs || sbi->s_stripe)
2618                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2619         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2620                         (sbi->s_mount_opt ^ def_mount_opt)) {
2621                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2622                         SEQ_OPTS_PUTS("data=journal");
2623                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2624                         SEQ_OPTS_PUTS("data=ordered");
2625                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2626                         SEQ_OPTS_PUTS("data=writeback");
2627         }
2628         if (nodefs ||
2629             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2630                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2631                                sbi->s_inode_readahead_blks);
2632
2633         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2634                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2635                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2636         if (nodefs || sbi->s_max_dir_size_kb)
2637                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2638         if (test_opt(sb, DATA_ERR_ABORT))
2639                 SEQ_OPTS_PUTS("data_err=abort");
2640
2641         fscrypt_show_test_dummy_encryption(seq, sep, sb);
2642
2643         if (sb->s_flags & SB_INLINECRYPT)
2644                 SEQ_OPTS_PUTS("inlinecrypt");
2645
2646         if (test_opt(sb, DAX_ALWAYS)) {
2647                 if (IS_EXT2_SB(sb))
2648                         SEQ_OPTS_PUTS("dax");
2649                 else
2650                         SEQ_OPTS_PUTS("dax=always");
2651         } else if (test_opt2(sb, DAX_NEVER)) {
2652                 SEQ_OPTS_PUTS("dax=never");
2653         } else if (test_opt2(sb, DAX_INODE)) {
2654                 SEQ_OPTS_PUTS("dax=inode");
2655         }
2656
2657         if (test_opt2(sb, JOURNAL_FAST_COMMIT))
2658                 SEQ_OPTS_PUTS("fast_commit");
2659
2660         ext4_show_quota_options(seq, sb);
2661         return 0;
2662 }
2663
2664 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2665 {
2666         return _ext4_show_options(seq, root->d_sb, 0);
2667 }
2668
2669 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2670 {
2671         struct super_block *sb = seq->private;
2672         int rc;
2673
2674         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2675         rc = _ext4_show_options(seq, sb, 1);
2676         seq_puts(seq, "\n");
2677         return rc;
2678 }
2679
2680 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2681                             int read_only)
2682 {
2683         struct ext4_sb_info *sbi = EXT4_SB(sb);
2684         int err = 0;
2685
2686         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2687                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2688                          "forcing read-only mode");
2689                 err = -EROFS;
2690                 goto done;
2691         }
2692         if (read_only)
2693                 goto done;
2694         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2695                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2696                          "running e2fsck is recommended");
2697         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2698                 ext4_msg(sb, KERN_WARNING,
2699                          "warning: mounting fs with errors, "
2700                          "running e2fsck is recommended");
2701         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2702                  le16_to_cpu(es->s_mnt_count) >=
2703                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2704                 ext4_msg(sb, KERN_WARNING,
2705                          "warning: maximal mount count reached, "
2706                          "running e2fsck is recommended");
2707         else if (le32_to_cpu(es->s_checkinterval) &&
2708                  (ext4_get_tstamp(es, s_lastcheck) +
2709                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2710                 ext4_msg(sb, KERN_WARNING,
2711                          "warning: checktime reached, "
2712                          "running e2fsck is recommended");
2713         if (!sbi->s_journal)
2714                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2715         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2716                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2717         le16_add_cpu(&es->s_mnt_count, 1);
2718         ext4_update_tstamp(es, s_mtime);
2719         if (sbi->s_journal)
2720                 ext4_set_feature_journal_needs_recovery(sb);
2721
2722         err = ext4_commit_super(sb, 1);
2723 done:
2724         if (test_opt(sb, DEBUG))
2725                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2726                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2727                         sb->s_blocksize,
2728                         sbi->s_groups_count,
2729                         EXT4_BLOCKS_PER_GROUP(sb),
2730                         EXT4_INODES_PER_GROUP(sb),
2731                         sbi->s_mount_opt, sbi->s_mount_opt2);
2732
2733         cleancache_init_fs(sb);
2734         return err;
2735 }
2736
2737 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2738 {
2739         struct ext4_sb_info *sbi = EXT4_SB(sb);
2740         struct flex_groups **old_groups, **new_groups;
2741         int size, i, j;
2742
2743         if (!sbi->s_log_groups_per_flex)
2744                 return 0;
2745
2746         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2747         if (size <= sbi->s_flex_groups_allocated)
2748                 return 0;
2749
2750         new_groups = kvzalloc(roundup_pow_of_two(size *
2751                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2752         if (!new_groups) {
2753                 ext4_msg(sb, KERN_ERR,
2754                          "not enough memory for %d flex group pointers", size);
2755                 return -ENOMEM;
2756         }
2757         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2758                 new_groups[i] = kvzalloc(roundup_pow_of_two(
2759                                          sizeof(struct flex_groups)),
2760                                          GFP_KERNEL);
2761                 if (!new_groups[i]) {
2762                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
2763                                 kvfree(new_groups[j]);
2764                         kvfree(new_groups);
2765                         ext4_msg(sb, KERN_ERR,
2766                                  "not enough memory for %d flex groups", size);
2767                         return -ENOMEM;
2768                 }
2769         }
2770         rcu_read_lock();
2771         old_groups = rcu_dereference(sbi->s_flex_groups);
2772         if (old_groups)
2773                 memcpy(new_groups, old_groups,
2774                        (sbi->s_flex_groups_allocated *
2775                         sizeof(struct flex_groups *)));
2776         rcu_read_unlock();
2777         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2778         sbi->s_flex_groups_allocated = size;
2779         if (old_groups)
2780                 ext4_kvfree_array_rcu(old_groups);
2781         return 0;
2782 }
2783
2784 static int ext4_fill_flex_info(struct super_block *sb)
2785 {
2786         struct ext4_sb_info *sbi = EXT4_SB(sb);
2787         struct ext4_group_desc *gdp = NULL;
2788         struct flex_groups *fg;
2789         ext4_group_t flex_group;
2790         int i, err;
2791
2792         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2793         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2794                 sbi->s_log_groups_per_flex = 0;
2795                 return 1;
2796         }
2797
2798         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2799         if (err)
2800                 goto failed;
2801
2802         for (i = 0; i < sbi->s_groups_count; i++) {
2803                 gdp = ext4_get_group_desc(sb, i, NULL);
2804
2805                 flex_group = ext4_flex_group(sbi, i);
2806                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2807                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2808                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2809                              &fg->free_clusters);
2810                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2811         }
2812
2813         return 1;
2814 failed:
2815         return 0;
2816 }
2817
2818 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2819                                    struct ext4_group_desc *gdp)
2820 {
2821         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2822         __u16 crc = 0;
2823         __le32 le_group = cpu_to_le32(block_group);
2824         struct ext4_sb_info *sbi = EXT4_SB(sb);
2825
2826         if (ext4_has_metadata_csum(sbi->s_sb)) {
2827                 /* Use new metadata_csum algorithm */
2828                 __u32 csum32;
2829                 __u16 dummy_csum = 0;
2830
2831                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2832                                      sizeof(le_group));
2833                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2834                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2835                                      sizeof(dummy_csum));
2836                 offset += sizeof(dummy_csum);
2837                 if (offset < sbi->s_desc_size)
2838                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2839                                              sbi->s_desc_size - offset);
2840
2841                 crc = csum32 & 0xFFFF;
2842                 goto out;
2843         }
2844
2845         /* old crc16 code */
2846         if (!ext4_has_feature_gdt_csum(sb))
2847                 return 0;
2848
2849         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2850         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2851         crc = crc16(crc, (__u8 *)gdp, offset);
2852         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2853         /* for checksum of struct ext4_group_desc do the rest...*/
2854         if (ext4_has_feature_64bit(sb) &&
2855             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2856                 crc = crc16(crc, (__u8 *)gdp + offset,
2857                             le16_to_cpu(sbi->s_es->s_desc_size) -
2858                                 offset);
2859
2860 out:
2861         return cpu_to_le16(crc);
2862 }
2863
2864 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2865                                 struct ext4_group_desc *gdp)
2866 {
2867         if (ext4_has_group_desc_csum(sb) &&
2868             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2869                 return 0;
2870
2871         return 1;
2872 }
2873
2874 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2875                               struct ext4_group_desc *gdp)
2876 {
2877         if (!ext4_has_group_desc_csum(sb))
2878                 return;
2879         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2880 }
2881
2882 /* Called at mount-time, super-block is locked */
2883 static int ext4_check_descriptors(struct super_block *sb,
2884                                   ext4_fsblk_t sb_block,
2885                                   ext4_group_t *first_not_zeroed)
2886 {
2887         struct ext4_sb_info *sbi = EXT4_SB(sb);
2888         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2889         ext4_fsblk_t last_block;
2890         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2891         ext4_fsblk_t block_bitmap;
2892         ext4_fsblk_t inode_bitmap;
2893         ext4_fsblk_t inode_table;
2894         int flexbg_flag = 0;
2895         ext4_group_t i, grp = sbi->s_groups_count;
2896
2897         if (ext4_has_feature_flex_bg(sb))
2898                 flexbg_flag = 1;
2899
2900         ext4_debug("Checking group descriptors");
2901
2902         for (i = 0; i < sbi->s_groups_count; i++) {
2903                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2904
2905                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2906                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2907                 else
2908                         last_block = first_block +
2909                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2910
2911                 if ((grp == sbi->s_groups_count) &&
2912                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2913                         grp = i;
2914
2915                 block_bitmap = ext4_block_bitmap(sb, gdp);
2916                 if (block_bitmap == sb_block) {
2917                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2918                                  "Block bitmap for group %u overlaps "
2919                                  "superblock", i);
2920                         if (!sb_rdonly(sb))
2921                                 return 0;
2922                 }
2923                 if (block_bitmap >= sb_block + 1 &&
2924                     block_bitmap <= last_bg_block) {
2925                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2926                                  "Block bitmap for group %u overlaps "
2927                                  "block group descriptors", i);
2928                         if (!sb_rdonly(sb))
2929                                 return 0;
2930                 }
2931                 if (block_bitmap < first_block || block_bitmap > last_block) {
2932                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2933                                "Block bitmap for group %u not in group "
2934                                "(block %llu)!", i, block_bitmap);
2935                         return 0;
2936                 }
2937                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2938                 if (inode_bitmap == sb_block) {
2939                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2940                                  "Inode bitmap for group %u overlaps "
2941                                  "superblock", i);
2942                         if (!sb_rdonly(sb))
2943                                 return 0;
2944                 }
2945                 if (inode_bitmap >= sb_block + 1 &&
2946                     inode_bitmap <= last_bg_block) {
2947                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2948                                  "Inode bitmap for group %u overlaps "
2949                                  "block group descriptors", i);
2950                         if (!sb_rdonly(sb))
2951                                 return 0;
2952                 }
2953                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2954                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2955                                "Inode bitmap for group %u not in group "
2956                                "(block %llu)!", i, inode_bitmap);
2957                         return 0;
2958                 }
2959                 inode_table = ext4_inode_table(sb, gdp);
2960                 if (inode_table == sb_block) {
2961                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2962                                  "Inode table for group %u overlaps "
2963                                  "superblock", i);
2964                         if (!sb_rdonly(sb))
2965                                 return 0;
2966                 }
2967                 if (inode_table >= sb_block + 1 &&
2968                     inode_table <= last_bg_block) {
2969                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2970                                  "Inode table for group %u overlaps "
2971                                  "block group descriptors", i);
2972                         if (!sb_rdonly(sb))
2973                                 return 0;
2974                 }
2975                 if (inode_table < first_block ||
2976                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2977                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2978                                "Inode table for group %u not in group "
2979                                "(block %llu)!", i, inode_table);
2980                         return 0;
2981                 }
2982                 ext4_lock_group(sb, i);
2983                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2984                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2985                                  "Checksum for group %u failed (%u!=%u)",
2986                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2987                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2988                         if (!sb_rdonly(sb)) {
2989                                 ext4_unlock_group(sb, i);
2990                                 return 0;
2991                         }
2992                 }
2993                 ext4_unlock_group(sb, i);
2994                 if (!flexbg_flag)
2995                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2996         }
2997         if (NULL != first_not_zeroed)
2998                 *first_not_zeroed = grp;
2999         return 1;
3000 }
3001
3002 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
3003  * the superblock) which were deleted from all directories, but held open by
3004  * a process at the time of a crash.  We walk the list and try to delete these
3005  * inodes at recovery time (only with a read-write filesystem).
3006  *
3007  * In order to keep the orphan inode chain consistent during traversal (in
3008  * case of crash during recovery), we link each inode into the superblock
3009  * orphan list_head and handle it the same way as an inode deletion during
3010  * normal operation (which journals the operations for us).
3011  *
3012  * We only do an iget() and an iput() on each inode, which is very safe if we
3013  * accidentally point at an in-use or already deleted inode.  The worst that
3014  * can happen in this case is that we get a "bit already cleared" message from
3015  * ext4_free_inode().  The only reason we would point at a wrong inode is if
3016  * e2fsck was run on this filesystem, and it must have already done the orphan
3017  * inode cleanup for us, so we can safely abort without any further action.
3018  */
3019 static void ext4_orphan_cleanup(struct super_block *sb,
3020                                 struct ext4_super_block *es)
3021 {
3022         unsigned int s_flags = sb->s_flags;
3023         int ret, nr_orphans = 0, nr_truncates = 0;
3024 #ifdef CONFIG_QUOTA
3025         int quota_update = 0;
3026         int i;
3027 #endif
3028         if (!es->s_last_orphan) {
3029                 jbd_debug(4, "no orphan inodes to clean up\n");
3030                 return;
3031         }
3032
3033         if (bdev_read_only(sb->s_bdev)) {
3034                 ext4_msg(sb, KERN_ERR, "write access "
3035                         "unavailable, skipping orphan cleanup");
3036                 return;
3037         }
3038
3039         /* Check if feature set would not allow a r/w mount */
3040         if (!ext4_feature_set_ok(sb, 0)) {
3041                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
3042                          "unknown ROCOMPAT features");
3043                 return;
3044         }
3045
3046         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
3047                 /* don't clear list on RO mount w/ errors */
3048                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
3049                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
3050                                   "clearing orphan list.\n");
3051                         es->s_last_orphan = 0;
3052                 }
3053                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
3054                 return;
3055         }
3056
3057         if (s_flags & SB_RDONLY) {
3058                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
3059                 sb->s_flags &= ~SB_RDONLY;
3060         }
3061 #ifdef CONFIG_QUOTA
3062         /* Needed for iput() to work correctly and not trash data */
3063         sb->s_flags |= SB_ACTIVE;
3064
3065         /*
3066          * Turn on quotas which were not enabled for read-only mounts if
3067          * filesystem has quota feature, so that they are updated correctly.
3068          */
3069         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
3070                 int ret = ext4_enable_quotas(sb);
3071
3072                 if (!ret)
3073                         quota_update = 1;
3074                 else
3075                         ext4_msg(sb, KERN_ERR,
3076                                 "Cannot turn on quotas: error %d", ret);
3077         }
3078
3079         /* Turn on journaled quotas used for old sytle */
3080         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3081                 if (EXT4_SB(sb)->s_qf_names[i]) {
3082                         int ret = ext4_quota_on_mount(sb, i);
3083
3084                         if (!ret)
3085                                 quota_update = 1;
3086                         else
3087                                 ext4_msg(sb, KERN_ERR,
3088                                         "Cannot turn on journaled "
3089                                         "quota: type %d: error %d", i, ret);
3090                 }
3091         }
3092 #endif
3093
3094         while (es->s_last_orphan) {
3095                 struct inode *inode;
3096
3097                 /*
3098                  * We may have encountered an error during cleanup; if
3099                  * so, skip the rest.
3100                  */
3101                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
3102                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
3103                         es->s_last_orphan = 0;
3104                         break;
3105                 }
3106
3107                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
3108                 if (IS_ERR(inode)) {
3109                         es->s_last_orphan = 0;
3110                         break;
3111                 }
3112
3113                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
3114                 dquot_initialize(inode);
3115                 if (inode->i_nlink) {
3116                         if (test_opt(sb, DEBUG))
3117                                 ext4_msg(sb, KERN_DEBUG,
3118                                         "%s: truncating inode %lu to %lld bytes",
3119                                         __func__, inode->i_ino, inode->i_size);
3120                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
3121                                   inode->i_ino, inode->i_size);
3122                         inode_lock(inode);
3123                         truncate_inode_pages(inode->i_mapping, inode->i_size);
3124                         ret = ext4_truncate(inode);
3125                         if (ret)
3126                                 ext4_std_error(inode->i_sb, ret);
3127                         inode_unlock(inode);
3128                         nr_truncates++;
3129                 } else {
3130                         if (test_opt(sb, DEBUG))
3131                                 ext4_msg(sb, KERN_DEBUG,
3132                                         "%s: deleting unreferenced inode %lu",
3133                                         __func__, inode->i_ino);
3134                         jbd_debug(2, "deleting unreferenced inode %lu\n",
3135                                   inode->i_ino);
3136                         nr_orphans++;
3137                 }
3138                 iput(inode);  /* The delete magic happens here! */
3139         }
3140
3141 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
3142
3143         if (nr_orphans)
3144                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
3145                        PLURAL(nr_orphans));
3146         if (nr_truncates)
3147                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
3148                        PLURAL(nr_truncates));
3149 #ifdef CONFIG_QUOTA
3150         /* Turn off quotas if they were enabled for orphan cleanup */
3151         if (quota_update) {
3152                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3153                         if (sb_dqopt(sb)->files[i])
3154                                 dquot_quota_off(sb, i);
3155                 }
3156         }
3157 #endif
3158         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
3159 }
3160
3161 /*
3162  * Maximal extent format file size.
3163  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3164  * extent format containers, within a sector_t, and within i_blocks
3165  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3166  * so that won't be a limiting factor.
3167  *
3168  * However there is other limiting factor. We do store extents in the form
3169  * of starting block and length, hence the resulting length of the extent
3170  * covering maximum file size must fit into on-disk format containers as
3171  * well. Given that length is always by 1 unit bigger than max unit (because
3172  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3173  *
3174  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3175  */
3176 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3177 {
3178         loff_t res;
3179         loff_t upper_limit = MAX_LFS_FILESIZE;
3180
3181         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3182
3183         if (!has_huge_files) {
3184                 upper_limit = (1LL << 32) - 1;
3185
3186                 /* total blocks in file system block size */
3187                 upper_limit >>= (blkbits - 9);
3188                 upper_limit <<= blkbits;
3189         }
3190
3191         /*
3192          * 32-bit extent-start container, ee_block. We lower the maxbytes
3193          * by one fs block, so ee_len can cover the extent of maximum file
3194          * size
3195          */
3196         res = (1LL << 32) - 1;
3197         res <<= blkbits;
3198
3199         /* Sanity check against vm- & vfs- imposed limits */
3200         if (res > upper_limit)
3201                 res = upper_limit;
3202
3203         return res;
3204 }
3205
3206 /*
3207  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3208  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3209  * We need to be 1 filesystem block less than the 2^48 sector limit.
3210  */
3211 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3212 {
3213         loff_t res = EXT4_NDIR_BLOCKS;
3214         int meta_blocks;
3215         loff_t upper_limit;
3216         /* This is calculated to be the largest file size for a dense, block
3217          * mapped file such that the file's total number of 512-byte sectors,
3218          * including data and all indirect blocks, does not exceed (2^48 - 1).
3219          *
3220          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3221          * number of 512-byte sectors of the file.
3222          */
3223
3224         if (!has_huge_files) {
3225                 /*
3226                  * !has_huge_files or implies that the inode i_block field
3227                  * represents total file blocks in 2^32 512-byte sectors ==
3228                  * size of vfs inode i_blocks * 8
3229                  */
3230                 upper_limit = (1LL << 32) - 1;
3231
3232                 /* total blocks in file system block size */
3233                 upper_limit >>= (bits - 9);
3234
3235         } else {
3236                 /*
3237                  * We use 48 bit ext4_inode i_blocks
3238                  * With EXT4_HUGE_FILE_FL set the i_blocks
3239                  * represent total number of blocks in
3240                  * file system block size
3241                  */
3242                 upper_limit = (1LL << 48) - 1;
3243
3244         }
3245
3246         /* indirect blocks */
3247         meta_blocks = 1;
3248         /* double indirect blocks */
3249         meta_blocks += 1 + (1LL << (bits-2));
3250         /* tripple indirect blocks */
3251         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
3252
3253         upper_limit -= meta_blocks;
3254         upper_limit <<= bits;
3255
3256         res += 1LL << (bits-2);
3257         res += 1LL << (2*(bits-2));
3258         res += 1LL << (3*(bits-2));
3259         res <<= bits;
3260         if (res > upper_limit)
3261                 res = upper_limit;
3262
3263         if (res > MAX_LFS_FILESIZE)
3264                 res = MAX_LFS_FILESIZE;
3265
3266         return res;
3267 }
3268
3269 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3270                                    ext4_fsblk_t logical_sb_block, int nr)
3271 {
3272         struct ext4_sb_info *sbi = EXT4_SB(sb);
3273         ext4_group_t bg, first_meta_bg;
3274         int has_super = 0;
3275
3276         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3277
3278         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3279                 return logical_sb_block + nr + 1;
3280         bg = sbi->s_desc_per_block * nr;
3281         if (ext4_bg_has_super(sb, bg))
3282                 has_super = 1;
3283
3284         /*
3285          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3286          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3287          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3288          * compensate.
3289          */
3290         if (sb->s_blocksize == 1024 && nr == 0 &&
3291             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3292                 has_super++;
3293
3294         return (has_super + ext4_group_first_block_no(sb, bg));
3295 }
3296
3297 /**
3298  * ext4_get_stripe_size: Get the stripe size.
3299  * @sbi: In memory super block info
3300  *
3301  * If we have specified it via mount option, then
3302  * use the mount option value. If the value specified at mount time is
3303  * greater than the blocks per group use the super block value.
3304  * If the super block value is greater than blocks per group return 0.
3305  * Allocator needs it be less than blocks per group.
3306  *
3307  */
3308 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3309 {
3310         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3311         unsigned long stripe_width =
3312                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3313         int ret;
3314
3315         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3316                 ret = sbi->s_stripe;
3317         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3318                 ret = stripe_width;
3319         else if (stride && stride <= sbi->s_blocks_per_group)
3320                 ret = stride;
3321         else
3322                 ret = 0;
3323
3324         /*
3325          * If the stripe width is 1, this makes no sense and
3326          * we set it to 0 to turn off stripe handling code.
3327          */
3328         if (ret <= 1)
3329                 ret = 0;
3330
3331         return ret;
3332 }
3333
3334 /*
3335  * Check whether this filesystem can be mounted based on
3336  * the features present and the RDONLY/RDWR mount requested.
3337  * Returns 1 if this filesystem can be mounted as requested,
3338  * 0 if it cannot be.
3339  */
3340 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
3341 {
3342         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3343                 ext4_msg(sb, KERN_ERR,
3344                         "Couldn't mount because of "
3345                         "unsupported optional features (%x)",
3346                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3347                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3348                 return 0;
3349         }
3350
3351 #ifndef CONFIG_UNICODE
3352         if (ext4_has_feature_casefold(sb)) {
3353                 ext4_msg(sb, KERN_ERR,
3354                          "Filesystem with casefold feature cannot be "
3355                          "mounted without CONFIG_UNICODE");
3356                 return 0;
3357         }
3358 #endif
3359
3360         if (readonly)
3361                 return 1;
3362
3363         if (ext4_has_feature_readonly(sb)) {
3364                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3365                 sb->s_flags |= SB_RDONLY;
3366                 return 1;
3367         }
3368
3369         /* Check that feature set is OK for a read-write mount */
3370         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3371                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3372                          "unsupported optional features (%x)",
3373                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3374                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3375                 return 0;
3376         }
3377         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3378                 ext4_msg(sb, KERN_ERR,
3379                          "Can't support bigalloc feature without "
3380                          "extents feature\n");
3381                 return 0;
3382         }
3383
3384 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3385         if (!readonly && (ext4_has_feature_quota(sb) ||
3386                           ext4_has_feature_project(sb))) {
3387                 ext4_msg(sb, KERN_ERR,
3388                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3389                 return 0;
3390         }
3391 #endif  /* CONFIG_QUOTA */
3392         return 1;
3393 }
3394
3395 /*
3396  * This function is called once a day if we have errors logged
3397  * on the file system
3398  */
3399 static void print_daily_error_info(struct timer_list *t)
3400 {
3401         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3402         struct super_block *sb = sbi->s_sb;
3403         struct ext4_super_block *es = sbi->s_es;
3404
3405         if (es->s_error_count)
3406                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3407                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3408                          le32_to_cpu(es->s_error_count));
3409         if (es->s_first_error_time) {
3410                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3411                        sb->s_id,
3412                        ext4_get_tstamp(es, s_first_error_time),
3413                        (int) sizeof(es->s_first_error_func),
3414                        es->s_first_error_func,
3415                        le32_to_cpu(es->s_first_error_line));
3416                 if (es->s_first_error_ino)
3417                         printk(KERN_CONT ": inode %u",
3418                                le32_to_cpu(es->s_first_error_ino));
3419                 if (es->s_first_error_block)
3420                         printk(KERN_CONT ": block %llu", (unsigned long long)
3421                                le64_to_cpu(es->s_first_error_block));
3422                 printk(KERN_CONT "\n");
3423         }
3424         if (es->s_last_error_time) {
3425                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3426                        sb->s_id,
3427                        ext4_get_tstamp(es, s_last_error_time),
3428                        (int) sizeof(es->s_last_error_func),
3429                        es->s_last_error_func,
3430                        le32_to_cpu(es->s_last_error_line));
3431                 if (es->s_last_error_ino)
3432                         printk(KERN_CONT ": inode %u",
3433                                le32_to_cpu(es->s_last_error_ino));
3434                 if (es->s_last_error_block)
3435                         printk(KERN_CONT ": block %llu", (unsigned long long)
3436                                le64_to_cpu(es->s_last_error_block));
3437                 printk(KERN_CONT "\n");
3438         }
3439         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3440 }
3441
3442 /* Find next suitable group and run ext4_init_inode_table */
3443 static int ext4_run_li_request(struct ext4_li_request *elr)
3444 {
3445         struct ext4_group_desc *gdp = NULL;
3446         struct super_block *sb = elr->lr_super;
3447         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3448         ext4_group_t group = elr->lr_next_group;
3449         unsigned long timeout = 0;
3450         unsigned int prefetch_ios = 0;
3451         int ret = 0;
3452
3453         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3454                 elr->lr_next_group = ext4_mb_prefetch(sb, group,
3455                                 EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3456                 if (prefetch_ios)
3457                         ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3458                                               prefetch_ios);
3459                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3460                                             prefetch_ios);
3461                 if (group >= elr->lr_next_group) {
3462                         ret = 1;
3463                         if (elr->lr_first_not_zeroed != ngroups &&
3464                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3465                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3466                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3467                                 ret = 0;
3468                         }
3469                 }
3470                 return ret;
3471         }
3472
3473         for (; group < ngroups; group++) {
3474                 gdp = ext4_get_group_desc(sb, group, NULL);
3475                 if (!gdp) {
3476                         ret = 1;
3477                         break;
3478                 }
3479
3480                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3481                         break;
3482         }
3483
3484         if (group >= ngroups)
3485                 ret = 1;
3486
3487         if (!ret) {
3488                 timeout = jiffies;
3489                 ret = ext4_init_inode_table(sb, group,
3490                                             elr->lr_timeout ? 0 : 1);
3491                 trace_ext4_lazy_itable_init(sb, group);
3492                 if (elr->lr_timeout == 0) {
3493                         timeout = (jiffies - timeout) *
3494                                 EXT4_SB(elr->lr_super)->s_li_wait_mult;
3495                         elr->lr_timeout = timeout;
3496                 }
3497                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3498                 elr->lr_next_group = group + 1;
3499         }
3500         return ret;
3501 }
3502
3503 /*
3504  * Remove lr_request from the list_request and free the
3505  * request structure. Should be called with li_list_mtx held
3506  */
3507 static void ext4_remove_li_request(struct ext4_li_request *elr)
3508 {
3509         if (!elr)
3510                 return;
3511
3512         list_del(&elr->lr_request);
3513         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3514         kfree(elr);
3515 }
3516
3517 static void ext4_unregister_li_request(struct super_block *sb)
3518 {
3519         mutex_lock(&ext4_li_mtx);
3520         if (!ext4_li_info) {
3521                 mutex_unlock(&ext4_li_mtx);
3522                 return;
3523         }
3524
3525         mutex_lock(&ext4_li_info->li_list_mtx);
3526         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3527         mutex_unlock(&ext4_li_info->li_list_mtx);
3528         mutex_unlock(&ext4_li_mtx);
3529 }
3530
3531 static struct task_struct *ext4_lazyinit_task;
3532
3533 /*
3534  * This is the function where ext4lazyinit thread lives. It walks
3535  * through the request list searching for next scheduled filesystem.
3536  * When such a fs is found, run the lazy initialization request
3537  * (ext4_rn_li_request) and keep track of the time spend in this
3538  * function. Based on that time we compute next schedule time of
3539  * the request. When walking through the list is complete, compute
3540  * next waking time and put itself into sleep.
3541  */
3542 static int ext4_lazyinit_thread(void *arg)
3543 {
3544         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3545         struct list_head *pos, *n;
3546         struct ext4_li_request *elr;
3547         unsigned long next_wakeup, cur;
3548
3549         BUG_ON(NULL == eli);
3550
3551 cont_thread:
3552         while (true) {
3553                 next_wakeup = MAX_JIFFY_OFFSET;
3554
3555                 mutex_lock(&eli->li_list_mtx);
3556                 if (list_empty(&eli->li_request_list)) {
3557                         mutex_unlock(&eli->li_list_mtx);
3558                         goto exit_thread;
3559                 }
3560                 list_for_each_safe(pos, n, &eli->li_request_list) {
3561                         int err = 0;
3562                         int progress = 0;
3563                         elr = list_entry(pos, struct ext4_li_request,
3564                                          lr_request);
3565
3566                         if (time_before(jiffies, elr->lr_next_sched)) {
3567                                 if (time_before(elr->lr_next_sched, next_wakeup))
3568                                         next_wakeup = elr->lr_next_sched;
3569                                 continue;
3570                         }
3571                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3572                                 if (sb_start_write_trylock(elr->lr_super)) {
3573                                         progress = 1;
3574                                         /*
3575                                          * We hold sb->s_umount, sb can not
3576                                          * be removed from the list, it is
3577                                          * now safe to drop li_list_mtx
3578                                          */
3579                                         mutex_unlock(&eli->li_list_mtx);
3580                                         err = ext4_run_li_request(elr);
3581                                         sb_end_write(elr->lr_super);
3582                                         mutex_lock(&eli->li_list_mtx);
3583                                         n = pos->next;
3584                                 }
3585                                 up_read((&elr->lr_super->s_umount));
3586                         }
3587                         /* error, remove the lazy_init job */
3588                         if (err) {
3589                                 ext4_remove_li_request(elr);
3590                                 continue;
3591                         }
3592                         if (!progress) {
3593                                 elr->lr_next_sched = jiffies +
3594                                         (prandom_u32()
3595                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3596                         }
3597                         if (time_before(elr->lr_next_sched, next_wakeup))
3598                                 next_wakeup = elr->lr_next_sched;
3599                 }
3600                 mutex_unlock(&eli->li_list_mtx);
3601
3602                 try_to_freeze();
3603
3604                 cur = jiffies;
3605                 if ((time_after_eq(cur, next_wakeup)) ||
3606                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3607                         cond_resched();
3608                         continue;
3609                 }
3610
3611                 schedule_timeout_interruptible(next_wakeup - cur);
3612
3613                 if (kthread_should_stop()) {
3614                         ext4_clear_request_list();
3615                         goto exit_thread;
3616                 }
3617         }
3618
3619 exit_thread:
3620         /*
3621          * It looks like the request list is empty, but we need
3622          * to check it under the li_list_mtx lock, to prevent any
3623          * additions into it, and of course we should lock ext4_li_mtx
3624          * to atomically free the list and ext4_li_info, because at
3625          * this point another ext4 filesystem could be registering
3626          * new one.
3627          */
3628         mutex_lock(&ext4_li_mtx);
3629         mutex_lock(&eli->li_list_mtx);
3630         if (!list_empty(&eli->li_request_list)) {
3631                 mutex_unlock(&eli->li_list_mtx);
3632                 mutex_unlock(&ext4_li_mtx);
3633                 goto cont_thread;
3634         }
3635         mutex_unlock(&eli->li_list_mtx);
3636         kfree(ext4_li_info);
3637         ext4_li_info = NULL;
3638         mutex_unlock(&ext4_li_mtx);
3639
3640         return 0;
3641 }
3642
3643 static void ext4_clear_request_list(void)
3644 {
3645         struct list_head *pos, *n;
3646         struct ext4_li_request *elr;
3647
3648         mutex_lock(&ext4_li_info->li_list_mtx);
3649         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3650                 elr = list_entry(pos, struct ext4_li_request,
3651                                  lr_request);
3652                 ext4_remove_li_request(elr);
3653         }
3654         mutex_unlock(&ext4_li_info->li_list_mtx);
3655 }
3656
3657 static int ext4_run_lazyinit_thread(void)
3658 {
3659         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3660                                          ext4_li_info, "ext4lazyinit");
3661         if (IS_ERR(ext4_lazyinit_task)) {
3662                 int err = PTR_ERR(ext4_lazyinit_task);
3663                 ext4_clear_request_list();
3664                 kfree(ext4_li_info);
3665                 ext4_li_info = NULL;
3666                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3667                                  "initialization thread\n",
3668                                  err);
3669                 return err;
3670         }
3671         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3672         return 0;
3673 }
3674
3675 /*
3676  * Check whether it make sense to run itable init. thread or not.
3677  * If there is at least one uninitialized inode table, return
3678  * corresponding group number, else the loop goes through all
3679  * groups and return total number of groups.
3680  */
3681 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3682 {
3683         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3684         struct ext4_group_desc *gdp = NULL;
3685
3686         if (!ext4_has_group_desc_csum(sb))
3687                 return ngroups;
3688
3689         for (group = 0; group < ngroups; group++) {
3690                 gdp = ext4_get_group_desc(sb, group, NULL);
3691                 if (!gdp)
3692                         continue;
3693
3694                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3695                         break;
3696         }
3697
3698         return group;
3699 }
3700
3701 static int ext4_li_info_new(void)
3702 {
3703         struct ext4_lazy_init *eli = NULL;
3704
3705         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3706         if (!eli)
3707                 return -ENOMEM;
3708
3709         INIT_LIST_HEAD(&eli->li_request_list);
3710         mutex_init(&eli->li_list_mtx);
3711
3712         eli->li_state |= EXT4_LAZYINIT_QUIT;
3713
3714         ext4_li_info = eli;
3715
3716         return 0;
3717 }
3718
3719 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3720                                             ext4_group_t start)
3721 {
3722         struct ext4_li_request *elr;
3723
3724         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3725         if (!elr)
3726                 return NULL;
3727
3728         elr->lr_super = sb;
3729         elr->lr_first_not_zeroed = start;
3730         if (test_opt(sb, PREFETCH_BLOCK_BITMAPS))
3731                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3732         else {
3733                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3734                 elr->lr_next_group = start;
3735         }
3736
3737         /*
3738          * Randomize first schedule time of the request to
3739          * spread the inode table initialization requests
3740          * better.
3741          */
3742         elr->lr_next_sched = jiffies + (prandom_u32() %
3743                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3744         return elr;
3745 }
3746
3747 int ext4_register_li_request(struct super_block *sb,
3748                              ext4_group_t first_not_zeroed)
3749 {
3750         struct ext4_sb_info *sbi = EXT4_SB(sb);
3751         struct ext4_li_request *elr = NULL;
3752         ext4_group_t ngroups = sbi->s_groups_count;
3753         int ret = 0;
3754
3755         mutex_lock(&ext4_li_mtx);
3756         if (sbi->s_li_request != NULL) {
3757                 /*
3758                  * Reset timeout so it can be computed again, because
3759                  * s_li_wait_mult might have changed.
3760                  */
3761                 sbi->s_li_request->lr_timeout = 0;
3762                 goto out;
3763         }
3764
3765         if (!test_opt(sb, PREFETCH_BLOCK_BITMAPS) &&
3766             (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3767              !test_opt(sb, INIT_INODE_TABLE)))
3768                 goto out;
3769
3770         elr = ext4_li_request_new(sb, first_not_zeroed);
3771         if (!elr) {
3772                 ret = -ENOMEM;
3773                 goto out;
3774         }
3775
3776         if (NULL == ext4_li_info) {
3777                 ret = ext4_li_info_new();
3778                 if (ret)
3779                         goto out;
3780         }
3781
3782         mutex_lock(&ext4_li_info->li_list_mtx);
3783         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3784         mutex_unlock(&ext4_li_info->li_list_mtx);
3785
3786         sbi->s_li_request = elr;
3787         /*
3788          * set elr to NULL here since it has been inserted to
3789          * the request_list and the removal and free of it is
3790          * handled by ext4_clear_request_list from now on.
3791          */
3792         elr = NULL;
3793
3794         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3795                 ret = ext4_run_lazyinit_thread();
3796                 if (ret)
3797                         goto out;
3798         }
3799 out:
3800         mutex_unlock(&ext4_li_mtx);
3801         if (ret)
3802                 kfree(elr);
3803         return ret;
3804 }
3805
3806 /*
3807  * We do not need to lock anything since this is called on
3808  * module unload.
3809  */
3810 static void ext4_destroy_lazyinit_thread(void)
3811 {
3812         /*
3813          * If thread exited earlier
3814          * there's nothing to be done.
3815          */
3816         if (!ext4_li_info || !ext4_lazyinit_task)
3817                 return;
3818
3819         kthread_stop(ext4_lazyinit_task);
3820 }
3821
3822 static int set_journal_csum_feature_set(struct super_block *sb)
3823 {
3824         int ret = 1;
3825         int compat, incompat;
3826         struct ext4_sb_info *sbi = EXT4_SB(sb);
3827
3828         if (ext4_has_metadata_csum(sb)) {
3829                 /* journal checksum v3 */
3830                 compat = 0;
3831                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3832         } else {
3833                 /* journal checksum v1 */
3834                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3835                 incompat = 0;
3836         }
3837
3838         jbd2_journal_clear_features(sbi->s_journal,
3839                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3840                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3841                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3842         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3843                 ret = jbd2_journal_set_features(sbi->s_journal,
3844                                 compat, 0,
3845                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3846                                 incompat);
3847         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3848                 ret = jbd2_journal_set_features(sbi->s_journal,
3849                                 compat, 0,
3850                                 incompat);
3851                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3852                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3853         } else {
3854                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3855                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3856         }
3857
3858         return ret;
3859 }
3860
3861 /*
3862  * Note: calculating the overhead so we can be compatible with
3863  * historical BSD practice is quite difficult in the face of
3864  * clusters/bigalloc.  This is because multiple metadata blocks from
3865  * different block group can end up in the same allocation cluster.
3866  * Calculating the exact overhead in the face of clustered allocation
3867  * requires either O(all block bitmaps) in memory or O(number of block
3868  * groups**2) in time.  We will still calculate the superblock for
3869  * older file systems --- and if we come across with a bigalloc file
3870  * system with zero in s_overhead_clusters the estimate will be close to
3871  * correct especially for very large cluster sizes --- but for newer
3872  * file systems, it's better to calculate this figure once at mkfs
3873  * time, and store it in the superblock.  If the superblock value is
3874  * present (even for non-bigalloc file systems), we will use it.
3875  */
3876 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3877                           char *buf)
3878 {
3879         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3880         struct ext4_group_desc  *gdp;
3881         ext4_fsblk_t            first_block, last_block, b;
3882         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3883         int                     s, j, count = 0;
3884
3885         if (!ext4_has_feature_bigalloc(sb))
3886                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3887                         sbi->s_itb_per_group + 2);
3888
3889         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3890                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3891         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3892         for (i = 0; i < ngroups; i++) {
3893                 gdp = ext4_get_group_desc(sb, i, NULL);
3894                 b = ext4_block_bitmap(sb, gdp);
3895                 if (b >= first_block && b <= last_block) {
3896                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3897                         count++;
3898                 }
3899                 b = ext4_inode_bitmap(sb, gdp);
3900                 if (b >= first_block && b <= last_block) {
3901                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3902                         count++;
3903                 }
3904                 b = ext4_inode_table(sb, gdp);
3905                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3906                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3907                                 int c = EXT4_B2C(sbi, b - first_block);
3908                                 ext4_set_bit(c, buf);
3909                                 count++;
3910                         }
3911                 if (i != grp)
3912                         continue;
3913                 s = 0;
3914                 if (ext4_bg_has_super(sb, grp)) {
3915                         ext4_set_bit(s++, buf);
3916                         count++;
3917                 }
3918                 j = ext4_bg_num_gdb(sb, grp);
3919                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3920                         ext4_error(sb, "Invalid number of block group "
3921                                    "descriptor blocks: %d", j);
3922                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3923                 }
3924                 count += j;
3925                 for (; j > 0; j--)
3926                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3927         }
3928         if (!count)
3929                 return 0;
3930         return EXT4_CLUSTERS_PER_GROUP(sb) -
3931                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3932 }
3933
3934 /*
3935  * Compute the overhead and stash it in sbi->s_overhead
3936  */
3937 int ext4_calculate_overhead(struct super_block *sb)
3938 {
3939         struct ext4_sb_info *sbi = EXT4_SB(sb);
3940         struct ext4_super_block *es = sbi->s_es;
3941         struct inode *j_inode;
3942         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3943         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3944         ext4_fsblk_t overhead = 0;
3945         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3946
3947         if (!buf)
3948                 return -ENOMEM;
3949
3950         /*
3951          * Compute the overhead (FS structures).  This is constant
3952          * for a given filesystem unless the number of block groups
3953          * changes so we cache the previous value until it does.
3954          */
3955
3956         /*
3957          * All of the blocks before first_data_block are overhead
3958          */
3959         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3960
3961         /*
3962          * Add the overhead found in each block group
3963          */
3964         for (i = 0; i < ngroups; i++) {
3965                 int blks;
3966
3967                 blks = count_overhead(sb, i, buf);
3968                 overhead += blks;
3969                 if (blks)
3970                         memset(buf, 0, PAGE_SIZE);
3971                 cond_resched();
3972         }
3973
3974         /*
3975          * Add the internal journal blocks whether the journal has been
3976          * loaded or not
3977          */
3978         if (sbi->s_journal && !sbi->s_journal_bdev)
3979                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3980         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3981                 /* j_inum for internal journal is non-zero */
3982                 j_inode = ext4_get_journal_inode(sb, j_inum);
3983                 if (j_inode) {
3984                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3985                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3986                         iput(j_inode);
3987                 } else {
3988                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3989                 }
3990         }
3991         sbi->s_overhead = overhead;
3992         smp_wmb();
3993         free_page((unsigned long) buf);
3994         return 0;
3995 }
3996
3997 static void ext4_set_resv_clusters(struct super_block *sb)
3998 {
3999         ext4_fsblk_t resv_clusters;
4000         struct ext4_sb_info *sbi = EXT4_SB(sb);
4001
4002         /*
4003          * There's no need to reserve anything when we aren't using extents.
4004          * The space estimates are exact, there are no unwritten extents,
4005          * hole punching doesn't need new metadata... This is needed especially
4006          * to keep ext2/3 backward compatibility.
4007          */
4008         if (!ext4_has_feature_extents(sb))
4009                 return;
4010         /*
4011          * By default we reserve 2% or 4096 clusters, whichever is smaller.
4012          * This should cover the situations where we can not afford to run
4013          * out of space like for example punch hole, or converting
4014          * unwritten extents in delalloc path. In most cases such
4015          * allocation would require 1, or 2 blocks, higher numbers are
4016          * very rare.
4017          */
4018         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4019                          sbi->s_cluster_bits);
4020
4021         do_div(resv_clusters, 50);
4022         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4023
4024         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4025 }
4026
4027 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
4028 {
4029         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
4030         char *orig_data = kstrdup(data, GFP_KERNEL);
4031         struct buffer_head *bh, **group_desc;
4032         struct ext4_super_block *es = NULL;
4033         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4034         struct flex_groups **flex_groups;
4035         ext4_fsblk_t block;
4036         ext4_fsblk_t sb_block = get_sb_block(&data);
4037         ext4_fsblk_t logical_sb_block;
4038         unsigned long offset = 0;
4039         unsigned long journal_devnum = 0;
4040         unsigned long def_mount_opts;
4041         struct inode *root;
4042         const char *descr;
4043         int ret = -ENOMEM;
4044         int blocksize, clustersize;
4045         unsigned int db_count;
4046         unsigned int i;
4047         int needs_recovery, has_huge_files;
4048         __u64 blocks_count;
4049         int err = 0;
4050         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4051         ext4_group_t first_not_zeroed;
4052
4053         if ((data && !orig_data) || !sbi)
4054                 goto out_free_base;
4055
4056         sbi->s_daxdev = dax_dev;
4057         sbi->s_blockgroup_lock =
4058                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4059         if (!sbi->s_blockgroup_lock)
4060                 goto out_free_base;
4061
4062         sb->s_fs_info = sbi;
4063         sbi->s_sb = sb;
4064         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
4065         sbi->s_sb_block = sb_block;
4066         if (sb->s_bdev->bd_part)
4067                 sbi->s_sectors_written_start =
4068                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
4069
4070         /* Cleanup superblock name */
4071         strreplace(sb->s_id, '/', '!');
4072
4073         /* -EINVAL is default */
4074         ret = -EINVAL;
4075         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
4076         if (!blocksize) {
4077                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
4078                 goto out_fail;
4079         }
4080
4081         /*
4082          * The ext4 superblock will not be buffer aligned for other than 1kB
4083          * block sizes.  We need to calculate the offset from buffer start.
4084          */
4085         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
4086                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4087                 offset = do_div(logical_sb_block, blocksize);
4088         } else {
4089                 logical_sb_block = sb_block;
4090         }
4091
4092         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4093         if (IS_ERR(bh)) {
4094                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
4095                 ret = PTR_ERR(bh);
4096                 bh = NULL;
4097                 goto out_fail;
4098         }
4099         /*
4100          * Note: s_es must be initialized as soon as possible because
4101          *       some ext4 macro-instructions depend on its value
4102          */
4103         es = (struct ext4_super_block *) (bh->b_data + offset);
4104         sbi->s_es = es;
4105         sb->s_magic = le16_to_cpu(es->s_magic);
4106         if (sb->s_magic != EXT4_SUPER_MAGIC)
4107                 goto cantfind_ext4;
4108         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
4109
4110         /* Warn if metadata_csum and gdt_csum are both set. */
4111         if (ext4_has_feature_metadata_csum(sb) &&
4112             ext4_has_feature_gdt_csum(sb))
4113                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4114                              "redundant flags; please run fsck.");
4115
4116         /* Check for a known checksum algorithm */
4117         if (!ext4_verify_csum_type(sb, es)) {
4118                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4119                          "unknown checksum algorithm.");
4120                 silent = 1;
4121                 goto cantfind_ext4;
4122         }
4123
4124         /* Load the checksum driver */
4125         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4126         if (IS_ERR(sbi->s_chksum_driver)) {
4127                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4128                 ret = PTR_ERR(sbi->s_chksum_driver);
4129                 sbi->s_chksum_driver = NULL;
4130                 goto failed_mount;
4131         }
4132
4133         /* Check superblock checksum */
4134         if (!ext4_superblock_csum_verify(sb, es)) {
4135                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4136                          "invalid superblock checksum.  Run e2fsck?");
4137                 silent = 1;
4138                 ret = -EFSBADCRC;
4139                 goto cantfind_ext4;
4140         }
4141
4142         /* Precompute checksum seed for all metadata */
4143         if (ext4_has_feature_csum_seed(sb))
4144                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4145         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4146                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4147                                                sizeof(es->s_uuid));
4148
4149         /* Set defaults before we parse the mount options */
4150         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4151         set_opt(sb, INIT_INODE_TABLE);
4152         if (def_mount_opts & EXT4_DEFM_DEBUG)
4153                 set_opt(sb, DEBUG);
4154         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4155                 set_opt(sb, GRPID);
4156         if (def_mount_opts & EXT4_DEFM_UID16)
4157                 set_opt(sb, NO_UID32);
4158         /* xattr user namespace & acls are now defaulted on */
4159         set_opt(sb, XATTR_USER);
4160 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4161         set_opt(sb, POSIX_ACL);
4162 #endif
4163         if (ext4_has_feature_fast_commit(sb))
4164                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4165         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4166         if (ext4_has_metadata_csum(sb))
4167                 set_opt(sb, JOURNAL_CHECKSUM);
4168
4169         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4170                 set_opt(sb, JOURNAL_DATA);
4171         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4172                 set_opt(sb, ORDERED_DATA);
4173         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4174                 set_opt(sb, WRITEBACK_DATA);
4175
4176         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
4177                 set_opt(sb, ERRORS_PANIC);
4178         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
4179                 set_opt(sb, ERRORS_CONT);
4180         else
4181                 set_opt(sb, ERRORS_RO);
4182         /* block_validity enabled by default; disable with noblock_validity */
4183         set_opt(sb, BLOCK_VALIDITY);
4184         if (def_mount_opts & EXT4_DEFM_DISCARD)
4185                 set_opt(sb, DISCARD);
4186
4187         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
4188         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
4189         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
4190         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
4191         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
4192
4193         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4194                 set_opt(sb, BARRIER);
4195
4196         /*
4197          * enable delayed allocation by default
4198          * Use -o nodelalloc to turn it off
4199          */
4200         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4201             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4202                 set_opt(sb, DELALLOC);
4203
4204         /*
4205          * set default s_li_wait_mult for lazyinit, for the case there is
4206          * no mount option specified.
4207          */
4208         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
4209
4210         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
4211
4212         if (blocksize == PAGE_SIZE)
4213                 set_opt(sb, DIOREAD_NOLOCK);
4214
4215         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
4216             blocksize > EXT4_MAX_BLOCK_SIZE) {
4217                 ext4_msg(sb, KERN_ERR,
4218                        "Unsupported filesystem blocksize %d (%d log_block_size)",
4219                          blocksize, le32_to_cpu(es->s_log_block_size));
4220                 goto failed_mount;
4221         }
4222
4223         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4224                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4225                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4226         } else {
4227                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4228                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4229                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4230                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4231                                  sbi->s_first_ino);
4232                         goto failed_mount;
4233                 }
4234                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4235                     (!is_power_of_2(sbi->s_inode_size)) ||
4236                     (sbi->s_inode_size > blocksize)) {
4237                         ext4_msg(sb, KERN_ERR,
4238                                "unsupported inode size: %d",
4239                                sbi->s_inode_size);
4240                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
4241                         goto failed_mount;
4242                 }
4243                 /*
4244                  * i_atime_extra is the last extra field available for
4245                  * [acm]times in struct ext4_inode. Checking for that
4246                  * field should suffice to ensure we have extra space
4247                  * for all three.
4248                  */
4249                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4250                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4251                         sb->s_time_gran = 1;
4252                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4253                 } else {
4254                         sb->s_time_gran = NSEC_PER_SEC;
4255                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4256                 }
4257                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4258         }
4259         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4260                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4261                         EXT4_GOOD_OLD_INODE_SIZE;
4262                 if (ext4_has_feature_extra_isize(sb)) {
4263                         unsigned v, max = (sbi->s_inode_size -
4264                                            EXT4_GOOD_OLD_INODE_SIZE);
4265
4266                         v = le16_to_cpu(es->s_want_extra_isize);
4267                         if (v > max) {
4268                                 ext4_msg(sb, KERN_ERR,
4269                                          "bad s_want_extra_isize: %d", v);
4270                                 goto failed_mount;
4271                         }
4272                         if (sbi->s_want_extra_isize < v)
4273                                 sbi->s_want_extra_isize = v;
4274
4275                         v = le16_to_cpu(es->s_min_extra_isize);
4276                         if (v > max) {
4277                                 ext4_msg(sb, KERN_ERR,
4278                                          "bad s_min_extra_isize: %d", v);
4279                                 goto failed_mount;
4280                         }
4281                         if (sbi->s_want_extra_isize < v)
4282                                 sbi->s_want_extra_isize = v;
4283                 }
4284         }
4285
4286         if (sbi->s_es->s_mount_opts[0]) {
4287                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
4288                                               sizeof(sbi->s_es->s_mount_opts),
4289                                               GFP_KERNEL);
4290                 if (!s_mount_opts)
4291                         goto failed_mount;
4292                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
4293                                    &journal_ioprio, 0)) {
4294                         ext4_msg(sb, KERN_WARNING,
4295                                  "failed to parse options in superblock: %s",
4296                                  s_mount_opts);
4297                 }
4298                 kfree(s_mount_opts);
4299         }
4300         sbi->s_def_mount_opt = sbi->s_mount_opt;
4301         if (!parse_options((char *) data, sb, &journal_devnum,
4302                            &journal_ioprio, 0))
4303                 goto failed_mount;
4304
4305 #ifdef CONFIG_UNICODE
4306         if (ext4_has_feature_casefold(sb) && !sbi->s_encoding) {
4307                 const struct ext4_sb_encodings *encoding_info;
4308                 struct unicode_map *encoding;
4309                 __u16 encoding_flags;
4310
4311                 if (ext4_has_feature_encrypt(sb)) {
4312                         ext4_msg(sb, KERN_ERR,
4313                                  "Can't mount with encoding and encryption");
4314                         goto failed_mount;
4315                 }
4316
4317                 if (ext4_sb_read_encoding(es, &encoding_info,
4318                                           &encoding_flags)) {
4319                         ext4_msg(sb, KERN_ERR,
4320                                  "Encoding requested by superblock is unknown");
4321                         goto failed_mount;
4322                 }
4323
4324                 encoding = utf8_load(encoding_info->version);
4325                 if (IS_ERR(encoding)) {
4326                         ext4_msg(sb, KERN_ERR,
4327                                  "can't mount with superblock charset: %s-%s "
4328                                  "not supported by the kernel. flags: 0x%x.",
4329                                  encoding_info->name, encoding_info->version,
4330                                  encoding_flags);
4331                         goto failed_mount;
4332                 }
4333                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4334                          "%s-%s with flags 0x%hx", encoding_info->name,
4335                          encoding_info->version?:"\b", encoding_flags);
4336
4337                 sbi->s_encoding = encoding;
4338                 sbi->s_encoding_flags = encoding_flags;
4339         }
4340 #endif
4341
4342         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4343                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, and O_DIRECT support!\n");
4344                 /* can't mount with both data=journal and dioread_nolock. */
4345                 clear_opt(sb, DIOREAD_NOLOCK);
4346                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4347                         ext4_msg(sb, KERN_ERR, "can't mount with "
4348                                  "both data=journal and delalloc");
4349                         goto failed_mount;
4350                 }
4351                 if (test_opt(sb, DAX_ALWAYS)) {
4352                         ext4_msg(sb, KERN_ERR, "can't mount with "
4353                                  "both data=journal and dax");
4354                         goto failed_mount;
4355                 }
4356                 if (ext4_has_feature_encrypt(sb)) {
4357                         ext4_msg(sb, KERN_WARNING,
4358                                  "encrypted files will use data=ordered "
4359                                  "instead of data journaling mode");
4360                 }
4361                 if (test_opt(sb, DELALLOC))
4362                         clear_opt(sb, DELALLOC);
4363         } else {
4364                 sb->s_iflags |= SB_I_CGROUPWB;
4365         }
4366
4367         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4368                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4369
4370         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4371             (ext4_has_compat_features(sb) ||
4372              ext4_has_ro_compat_features(sb) ||
4373              ext4_has_incompat_features(sb)))
4374                 ext4_msg(sb, KERN_WARNING,
4375                        "feature flags set on rev 0 fs, "
4376                        "running e2fsck is recommended");
4377
4378         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4379                 set_opt2(sb, HURD_COMPAT);
4380                 if (ext4_has_feature_64bit(sb)) {
4381                         ext4_msg(sb, KERN_ERR,
4382                                  "The Hurd can't support 64-bit file systems");
4383                         goto failed_mount;
4384                 }
4385
4386                 /*
4387                  * ea_inode feature uses l_i_version field which is not
4388                  * available in HURD_COMPAT mode.
4389                  */
4390                 if (ext4_has_feature_ea_inode(sb)) {
4391                         ext4_msg(sb, KERN_ERR,
4392                                  "ea_inode feature is not supported for Hurd");
4393                         goto failed_mount;
4394                 }
4395         }
4396
4397         if (IS_EXT2_SB(sb)) {
4398                 if (ext2_feature_set_ok(sb))
4399                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4400                                  "using the ext4 subsystem");
4401                 else {
4402                         /*
4403                          * If we're probing be silent, if this looks like
4404                          * it's actually an ext[34] filesystem.
4405                          */
4406                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4407                                 goto failed_mount;
4408                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4409                                  "to feature incompatibilities");
4410                         goto failed_mount;
4411                 }
4412         }
4413
4414         if (IS_EXT3_SB(sb)) {
4415                 if (ext3_feature_set_ok(sb))
4416                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4417                                  "using the ext4 subsystem");
4418                 else {
4419                         /*
4420                          * If we're probing be silent, if this looks like
4421                          * it's actually an ext4 filesystem.
4422                          */
4423                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4424                                 goto failed_mount;
4425                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4426                                  "to feature incompatibilities");
4427                         goto failed_mount;
4428                 }
4429         }
4430
4431         /*
4432          * Check feature flags regardless of the revision level, since we
4433          * previously didn't change the revision level when setting the flags,
4434          * so there is a chance incompat flags are set on a rev 0 filesystem.
4435          */
4436         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4437                 goto failed_mount;
4438
4439         if (le32_to_cpu(es->s_log_block_size) >
4440             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4441                 ext4_msg(sb, KERN_ERR,
4442                          "Invalid log block size: %u",
4443                          le32_to_cpu(es->s_log_block_size));
4444                 goto failed_mount;
4445         }
4446         if (le32_to_cpu(es->s_log_cluster_size) >
4447             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4448                 ext4_msg(sb, KERN_ERR,
4449                          "Invalid log cluster size: %u",
4450                          le32_to_cpu(es->s_log_cluster_size));
4451                 goto failed_mount;
4452         }
4453
4454         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4455                 ext4_msg(sb, KERN_ERR,
4456                          "Number of reserved GDT blocks insanely large: %d",
4457                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4458                 goto failed_mount;
4459         }
4460
4461         if (bdev_dax_supported(sb->s_bdev, blocksize))
4462                 set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4463
4464         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4465                 if (ext4_has_feature_inline_data(sb)) {
4466                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4467                                         " that may contain inline data");
4468                         goto failed_mount;
4469                 }
4470                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4471                         ext4_msg(sb, KERN_ERR,
4472                                 "DAX unsupported by block device.");
4473                         goto failed_mount;
4474                 }
4475         }
4476
4477         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4478                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4479                          es->s_encryption_level);
4480                 goto failed_mount;
4481         }
4482
4483         if (sb->s_blocksize != blocksize) {
4484                 /* Validate the filesystem blocksize */
4485                 if (!sb_set_blocksize(sb, blocksize)) {
4486                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4487                                         blocksize);
4488                         goto failed_mount;
4489                 }
4490
4491                 brelse(bh);
4492                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4493                 offset = do_div(logical_sb_block, blocksize);
4494                 bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4495                 if (IS_ERR(bh)) {
4496                         ext4_msg(sb, KERN_ERR,
4497                                "Can't read superblock on 2nd try");
4498                         ret = PTR_ERR(bh);
4499                         bh = NULL;
4500                         goto failed_mount;
4501                 }
4502                 es = (struct ext4_super_block *)(bh->b_data + offset);
4503                 sbi->s_es = es;
4504                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4505                         ext4_msg(sb, KERN_ERR,
4506                                "Magic mismatch, very weird!");
4507                         goto failed_mount;
4508                 }
4509         }
4510
4511         has_huge_files = ext4_has_feature_huge_file(sb);
4512         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4513                                                       has_huge_files);
4514         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4515
4516         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4517         if (ext4_has_feature_64bit(sb)) {
4518                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4519                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4520                     !is_power_of_2(sbi->s_desc_size)) {
4521                         ext4_msg(sb, KERN_ERR,
4522                                "unsupported descriptor size %lu",
4523                                sbi->s_desc_size);
4524                         goto failed_mount;
4525                 }
4526         } else
4527                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4528
4529         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4530         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4531
4532         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4533         if (sbi->s_inodes_per_block == 0)
4534                 goto cantfind_ext4;
4535         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4536             sbi->s_inodes_per_group > blocksize * 8) {
4537                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4538                          sbi->s_inodes_per_group);
4539                 goto failed_mount;
4540         }
4541         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4542                                         sbi->s_inodes_per_block;
4543         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4544         sbi->s_sbh = bh;
4545         sbi->s_mount_state = le16_to_cpu(es->s_state);
4546         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4547         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4548
4549         for (i = 0; i < 4; i++)
4550                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4551         sbi->s_def_hash_version = es->s_def_hash_version;
4552         if (ext4_has_feature_dir_index(sb)) {
4553                 i = le32_to_cpu(es->s_flags);
4554                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4555                         sbi->s_hash_unsigned = 3;
4556                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4557 #ifdef __CHAR_UNSIGNED__
4558                         if (!sb_rdonly(sb))
4559                                 es->s_flags |=
4560                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4561                         sbi->s_hash_unsigned = 3;
4562 #else
4563                         if (!sb_rdonly(sb))
4564                                 es->s_flags |=
4565                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4566 #endif
4567                 }
4568         }
4569
4570         /* Handle clustersize */
4571         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4572         if (ext4_has_feature_bigalloc(sb)) {
4573                 if (clustersize < blocksize) {
4574                         ext4_msg(sb, KERN_ERR,
4575                                  "cluster size (%d) smaller than "
4576                                  "block size (%d)", clustersize, blocksize);
4577                         goto failed_mount;
4578                 }
4579                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4580                         le32_to_cpu(es->s_log_block_size);
4581                 sbi->s_clusters_per_group =
4582                         le32_to_cpu(es->s_clusters_per_group);
4583                 if (sbi->s_clusters_per_group > blocksize * 8) {
4584                         ext4_msg(sb, KERN_ERR,
4585                                  "#clusters per group too big: %lu",
4586                                  sbi->s_clusters_per_group);
4587                         goto failed_mount;
4588                 }
4589                 if (sbi->s_blocks_per_group !=
4590                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4591                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4592                                  "clusters per group (%lu) inconsistent",
4593                                  sbi->s_blocks_per_group,
4594                                  sbi->s_clusters_per_group);
4595                         goto failed_mount;
4596                 }
4597         } else {
4598                 if (clustersize != blocksize) {
4599                         ext4_msg(sb, KERN_ERR,
4600                                  "fragment/cluster size (%d) != "
4601                                  "block size (%d)", clustersize, blocksize);
4602                         goto failed_mount;
4603                 }
4604                 if (sbi->s_blocks_per_group > blocksize * 8) {
4605                         ext4_msg(sb, KERN_ERR,
4606                                  "#blocks per group too big: %lu",
4607                                  sbi->s_blocks_per_group);
4608                         goto failed_mount;
4609                 }
4610                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4611                 sbi->s_cluster_bits = 0;
4612         }
4613         sbi->s_cluster_ratio = clustersize / blocksize;
4614
4615         /* Do we have standard group size of clustersize * 8 blocks ? */
4616         if (sbi->s_blocks_per_group == clustersize << 3)
4617                 set_opt2(sb, STD_GROUP_SIZE);
4618
4619         /*
4620          * Test whether we have more sectors than will fit in sector_t,
4621          * and whether the max offset is addressable by the page cache.
4622          */
4623         err = generic_check_addressable(sb->s_blocksize_bits,
4624                                         ext4_blocks_count(es));
4625         if (err) {
4626                 ext4_msg(sb, KERN_ERR, "filesystem"
4627                          " too large to mount safely on this system");
4628                 goto failed_mount;
4629         }
4630
4631         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4632                 goto cantfind_ext4;
4633
4634         /* check blocks count against device size */
4635         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4636         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4637                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4638                        "exceeds size of device (%llu blocks)",
4639                        ext4_blocks_count(es), blocks_count);
4640                 goto failed_mount;
4641         }
4642
4643         /*
4644          * It makes no sense for the first data block to be beyond the end
4645          * of the filesystem.
4646          */
4647         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4648                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4649                          "block %u is beyond end of filesystem (%llu)",
4650                          le32_to_cpu(es->s_first_data_block),
4651                          ext4_blocks_count(es));
4652                 goto failed_mount;
4653         }
4654         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4655             (sbi->s_cluster_ratio == 1)) {
4656                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4657                          "block is 0 with a 1k block and cluster size");
4658                 goto failed_mount;
4659         }
4660
4661         blocks_count = (ext4_blocks_count(es) -
4662                         le32_to_cpu(es->s_first_data_block) +
4663                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4664         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4665         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4666                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4667                        "(block count %llu, first data block %u, "
4668                        "blocks per group %lu)", blocks_count,
4669                        ext4_blocks_count(es),
4670                        le32_to_cpu(es->s_first_data_block),
4671                        EXT4_BLOCKS_PER_GROUP(sb));
4672                 goto failed_mount;
4673         }
4674         sbi->s_groups_count = blocks_count;
4675         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4676                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4677         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4678             le32_to_cpu(es->s_inodes_count)) {
4679                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4680                          le32_to_cpu(es->s_inodes_count),
4681                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4682                 ret = -EINVAL;
4683                 goto failed_mount;
4684         }
4685         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4686                    EXT4_DESC_PER_BLOCK(sb);
4687         if (ext4_has_feature_meta_bg(sb)) {
4688                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4689                         ext4_msg(sb, KERN_WARNING,
4690                                  "first meta block group too large: %u "
4691                                  "(group descriptor block count %u)",
4692                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4693                         goto failed_mount;
4694                 }
4695         }
4696         rcu_assign_pointer(sbi->s_group_desc,
4697                            kvmalloc_array(db_count,
4698                                           sizeof(struct buffer_head *),
4699                                           GFP_KERNEL));
4700         if (sbi->s_group_desc == NULL) {
4701                 ext4_msg(sb, KERN_ERR, "not enough memory");
4702                 ret = -ENOMEM;
4703                 goto failed_mount;
4704         }
4705
4706         bgl_lock_init(sbi->s_blockgroup_lock);
4707
4708         /* Pre-read the descriptors into the buffer cache */
4709         for (i = 0; i < db_count; i++) {
4710                 block = descriptor_loc(sb, logical_sb_block, i);
4711                 ext4_sb_breadahead_unmovable(sb, block);
4712         }
4713
4714         for (i = 0; i < db_count; i++) {
4715                 struct buffer_head *bh;
4716
4717                 block = descriptor_loc(sb, logical_sb_block, i);
4718                 bh = ext4_sb_bread_unmovable(sb, block);
4719                 if (IS_ERR(bh)) {
4720                         ext4_msg(sb, KERN_ERR,
4721                                "can't read group descriptor %d", i);
4722                         db_count = i;
4723                         ret = PTR_ERR(bh);
4724                         bh = NULL;
4725                         goto failed_mount2;
4726                 }
4727                 rcu_read_lock();
4728                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4729                 rcu_read_unlock();
4730         }
4731         sbi->s_gdb_count = db_count;
4732         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4733                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4734                 ret = -EFSCORRUPTED;
4735                 goto failed_mount2;
4736         }
4737
4738         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4739
4740         /* Register extent status tree shrinker */
4741         if (ext4_es_register_shrinker(sbi))
4742                 goto failed_mount3;
4743
4744         sbi->s_stripe = ext4_get_stripe_size(sbi);
4745         sbi->s_extent_max_zeroout_kb = 32;
4746
4747         /*
4748          * set up enough so that it can read an inode
4749          */
4750         sb->s_op = &ext4_sops;
4751         sb->s_export_op = &ext4_export_ops;
4752         sb->s_xattr = ext4_xattr_handlers;
4753 #ifdef CONFIG_FS_ENCRYPTION
4754         sb->s_cop = &ext4_cryptops;
4755 #endif
4756 #ifdef CONFIG_FS_VERITY
4757         sb->s_vop = &ext4_verityops;
4758 #endif
4759 #ifdef CONFIG_QUOTA
4760         sb->dq_op = &ext4_quota_operations;
4761         if (ext4_has_feature_quota(sb))
4762                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4763         else
4764                 sb->s_qcop = &ext4_qctl_operations;
4765         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4766 #endif
4767         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4768
4769         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4770         mutex_init(&sbi->s_orphan_lock);
4771
4772         /* Initialize fast commit stuff */
4773         atomic_set(&sbi->s_fc_subtid, 0);
4774         atomic_set(&sbi->s_fc_ineligible_updates, 0);
4775         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4776         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4777         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4778         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4779         sbi->s_fc_bytes = 0;
4780         sbi->s_mount_state &= ~EXT4_FC_INELIGIBLE;
4781         sbi->s_mount_state &= ~EXT4_FC_COMMITTING;
4782         spin_lock_init(&sbi->s_fc_lock);
4783         memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4784         sbi->s_fc_replay_state.fc_regions = NULL;
4785         sbi->s_fc_replay_state.fc_regions_size = 0;
4786         sbi->s_fc_replay_state.fc_regions_used = 0;
4787         sbi->s_fc_replay_state.fc_regions_valid = 0;
4788         sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4789         sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4790         sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4791
4792         sb->s_root = NULL;
4793
4794         needs_recovery = (es->s_last_orphan != 0 ||
4795                           ext4_has_feature_journal_needs_recovery(sb));
4796
4797         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4798                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4799                         goto failed_mount3a;
4800
4801         /*
4802          * The first inode we look at is the journal inode.  Don't try
4803          * root first: it may be modified in the journal!
4804          */
4805         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4806                 err = ext4_load_journal(sb, es, journal_devnum);
4807                 if (err)
4808                         goto failed_mount3a;
4809         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4810                    ext4_has_feature_journal_needs_recovery(sb)) {
4811                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4812                        "suppressed and not mounted read-only");
4813                 goto failed_mount_wq;
4814         } else {
4815                 /* Nojournal mode, all journal mount options are illegal */
4816                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4817                         ext4_msg(sb, KERN_ERR, "can't mount with "
4818                                  "journal_checksum, fs mounted w/o journal");
4819                         goto failed_mount_wq;
4820                 }
4821                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4822                         ext4_msg(sb, KERN_ERR, "can't mount with "
4823                                  "journal_async_commit, fs mounted w/o journal");
4824                         goto failed_mount_wq;
4825                 }
4826                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4827                         ext4_msg(sb, KERN_ERR, "can't mount with "
4828                                  "commit=%lu, fs mounted w/o journal",
4829                                  sbi->s_commit_interval / HZ);
4830                         goto failed_mount_wq;
4831                 }
4832                 if (EXT4_MOUNT_DATA_FLAGS &
4833                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4834                         ext4_msg(sb, KERN_ERR, "can't mount with "
4835                                  "data=, fs mounted w/o journal");
4836                         goto failed_mount_wq;
4837                 }
4838                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4839                 clear_opt(sb, JOURNAL_CHECKSUM);
4840                 clear_opt(sb, DATA_FLAGS);
4841                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4842                 sbi->s_journal = NULL;
4843                 needs_recovery = 0;
4844                 goto no_journal;
4845         }
4846
4847         if (ext4_has_feature_64bit(sb) &&
4848             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4849                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4850                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4851                 goto failed_mount_wq;
4852         }
4853
4854         if (!set_journal_csum_feature_set(sb)) {
4855                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4856                          "feature set");
4857                 goto failed_mount_wq;
4858         }
4859
4860         /* We have now updated the journal if required, so we can
4861          * validate the data journaling mode. */
4862         switch (test_opt(sb, DATA_FLAGS)) {
4863         case 0:
4864                 /* No mode set, assume a default based on the journal
4865                  * capabilities: ORDERED_DATA if the journal can
4866                  * cope, else JOURNAL_DATA
4867                  */
4868                 if (jbd2_journal_check_available_features
4869                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4870                         set_opt(sb, ORDERED_DATA);
4871                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4872                 } else {
4873                         set_opt(sb, JOURNAL_DATA);
4874                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4875                 }
4876                 break;
4877
4878         case EXT4_MOUNT_ORDERED_DATA:
4879         case EXT4_MOUNT_WRITEBACK_DATA:
4880                 if (!jbd2_journal_check_available_features
4881                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4882                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4883                                "requested data journaling mode");
4884                         goto failed_mount_wq;
4885                 }
4886         default:
4887                 break;
4888         }
4889
4890         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4891             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4892                 ext4_msg(sb, KERN_ERR, "can't mount with "
4893                         "journal_async_commit in data=ordered mode");
4894                 goto failed_mount_wq;
4895         }
4896
4897         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4898
4899         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4900         sbi->s_journal->j_submit_inode_data_buffers =
4901                 ext4_journal_submit_inode_data_buffers;
4902         sbi->s_journal->j_finish_inode_data_buffers =
4903                 ext4_journal_finish_inode_data_buffers;
4904
4905 no_journal:
4906         if (!test_opt(sb, NO_MBCACHE)) {
4907                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4908                 if (!sbi->s_ea_block_cache) {
4909                         ext4_msg(sb, KERN_ERR,
4910                                  "Failed to create ea_block_cache");
4911                         goto failed_mount_wq;
4912                 }
4913
4914                 if (ext4_has_feature_ea_inode(sb)) {
4915                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4916                         if (!sbi->s_ea_inode_cache) {
4917                                 ext4_msg(sb, KERN_ERR,
4918                                          "Failed to create ea_inode_cache");
4919                                 goto failed_mount_wq;
4920                         }
4921                 }
4922         }
4923
4924         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4925                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4926                 goto failed_mount_wq;
4927         }
4928
4929         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4930             !ext4_has_feature_encrypt(sb)) {
4931                 ext4_set_feature_encrypt(sb);
4932                 ext4_commit_super(sb, 1);
4933         }
4934
4935         /*
4936          * Get the # of file system overhead blocks from the
4937          * superblock if present.
4938          */
4939         if (es->s_overhead_clusters)
4940                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4941         else {
4942                 err = ext4_calculate_overhead(sb);
4943                 if (err)
4944                         goto failed_mount_wq;
4945         }
4946
4947         /*
4948          * The maximum number of concurrent works can be high and
4949          * concurrency isn't really necessary.  Limit it to 1.
4950          */
4951         EXT4_SB(sb)->rsv_conversion_wq =
4952                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4953         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4954                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4955                 ret = -ENOMEM;
4956                 goto failed_mount4;
4957         }
4958
4959         /*
4960          * The jbd2_journal_load will have done any necessary log recovery,
4961          * so we can safely mount the rest of the filesystem now.
4962          */
4963
4964         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4965         if (IS_ERR(root)) {
4966                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4967                 ret = PTR_ERR(root);
4968                 root = NULL;
4969                 goto failed_mount4;
4970         }
4971         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4972                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4973                 iput(root);
4974                 goto failed_mount4;
4975         }
4976
4977 #ifdef CONFIG_UNICODE
4978         if (sbi->s_encoding)
4979                 sb->s_d_op = &ext4_dentry_ops;
4980 #endif
4981
4982         sb->s_root = d_make_root(root);
4983         if (!sb->s_root) {
4984                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4985                 ret = -ENOMEM;
4986                 goto failed_mount4;
4987         }
4988
4989         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4990         if (ret == -EROFS) {
4991                 sb->s_flags |= SB_RDONLY;
4992                 ret = 0;
4993         } else if (ret)
4994                 goto failed_mount4a;
4995
4996         ext4_set_resv_clusters(sb);
4997
4998         if (test_opt(sb, BLOCK_VALIDITY)) {
4999                 err = ext4_setup_system_zone(sb);
5000                 if (err) {
5001                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
5002                                  "zone (%d)", err);
5003                         goto failed_mount4a;
5004                 }
5005         }
5006         ext4_fc_replay_cleanup(sb);
5007
5008         ext4_ext_init(sb);
5009         err = ext4_mb_init(sb);
5010         if (err) {
5011                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5012                          err);
5013                 goto failed_mount5;
5014         }
5015
5016         block = ext4_count_free_clusters(sb);
5017         ext4_free_blocks_count_set(sbi->s_es,
5018                                    EXT4_C2B(sbi, block));
5019         ext4_superblock_csum_set(sb);
5020         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
5021                                   GFP_KERNEL);
5022         if (!err) {
5023                 unsigned long freei = ext4_count_free_inodes(sb);
5024                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
5025                 ext4_superblock_csum_set(sb);
5026                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
5027                                           GFP_KERNEL);
5028         }
5029         if (!err)
5030                 err = percpu_counter_init(&sbi->s_dirs_counter,
5031                                           ext4_count_dirs(sb), GFP_KERNEL);
5032         if (!err)
5033                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
5034                                           GFP_KERNEL);
5035         if (!err)
5036                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
5037
5038         if (err) {
5039                 ext4_msg(sb, KERN_ERR, "insufficient memory");
5040                 goto failed_mount6;
5041         }
5042
5043         if (ext4_has_feature_flex_bg(sb))
5044                 if (!ext4_fill_flex_info(sb)) {
5045                         ext4_msg(sb, KERN_ERR,
5046                                "unable to initialize "
5047                                "flex_bg meta info!");
5048                         goto failed_mount6;
5049                 }
5050
5051         err = ext4_register_li_request(sb, first_not_zeroed);
5052         if (err)
5053                 goto failed_mount6;
5054
5055         err = ext4_register_sysfs(sb);
5056         if (err)
5057                 goto failed_mount7;
5058
5059 #ifdef CONFIG_QUOTA
5060         /* Enable quota usage during mount. */
5061         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5062                 err = ext4_enable_quotas(sb);
5063                 if (err)
5064                         goto failed_mount8;
5065         }
5066 #endif  /* CONFIG_QUOTA */
5067
5068         /*
5069          * Save the original bdev mapping's wb_err value which could be
5070          * used to detect the metadata async write error.
5071          */
5072         spin_lock_init(&sbi->s_bdev_wb_lock);
5073         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5074                                  &sbi->s_bdev_wb_err);
5075         sb->s_bdev->bd_super = sb;
5076         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5077         ext4_orphan_cleanup(sb, es);
5078         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5079         if (needs_recovery) {
5080                 ext4_msg(sb, KERN_INFO, "recovery complete");
5081                 err = ext4_mark_recovery_complete(sb, es);
5082                 if (err)
5083                         goto failed_mount8;
5084         }
5085         if (EXT4_SB(sb)->s_journal) {
5086                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5087                         descr = " journalled data mode";
5088                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5089                         descr = " ordered data mode";
5090                 else
5091                         descr = " writeback data mode";
5092         } else
5093                 descr = "out journal";
5094
5095         if (test_opt(sb, DISCARD)) {
5096                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
5097                 if (!blk_queue_discard(q))
5098                         ext4_msg(sb, KERN_WARNING,
5099                                  "mounting with \"discard\" option, but "
5100                                  "the device does not support discard");
5101         }
5102
5103         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5104                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
5105                          "Opts: %.*s%s%s", descr,
5106                          (int) sizeof(sbi->s_es->s_mount_opts),
5107                          sbi->s_es->s_mount_opts,
5108                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
5109
5110         if (es->s_error_count)
5111                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5112
5113         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5114         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5115         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5116         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5117         atomic_set(&sbi->s_warning_count, 0);
5118         atomic_set(&sbi->s_msg_count, 0);
5119
5120         kfree(orig_data);
5121         return 0;
5122
5123 cantfind_ext4:
5124         if (!silent)
5125                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5126         goto failed_mount;
5127
5128 failed_mount8:
5129         ext4_unregister_sysfs(sb);
5130         kobject_put(&sbi->s_kobj);
5131 failed_mount7:
5132         ext4_unregister_li_request(sb);
5133 failed_mount6:
5134         ext4_mb_release(sb);
5135         rcu_read_lock();
5136         flex_groups = rcu_dereference(sbi->s_flex_groups);
5137         if (flex_groups) {
5138                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
5139                         kvfree(flex_groups[i]);
5140                 kvfree(flex_groups);
5141         }
5142         rcu_read_unlock();
5143         percpu_counter_destroy(&sbi->s_freeclusters_counter);
5144         percpu_counter_destroy(&sbi->s_freeinodes_counter);
5145         percpu_counter_destroy(&sbi->s_dirs_counter);
5146         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
5147         percpu_free_rwsem(&sbi->s_writepages_rwsem);
5148 failed_mount5:
5149         ext4_ext_release(sb);
5150         ext4_release_system_zone(sb);
5151 failed_mount4a:
5152         dput(sb->s_root);
5153         sb->s_root = NULL;
5154 failed_mount4:
5155         ext4_msg(sb, KERN_ERR, "mount failed");
5156         if (EXT4_SB(sb)->rsv_conversion_wq)
5157                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5158 failed_mount_wq:
5159         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5160         sbi->s_ea_inode_cache = NULL;
5161
5162         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5163         sbi->s_ea_block_cache = NULL;
5164
5165         if (sbi->s_journal) {
5166                 jbd2_journal_destroy(sbi->s_journal);
5167                 sbi->s_journal = NULL;
5168         }
5169 failed_mount3a:
5170         ext4_es_unregister_shrinker(sbi);
5171 failed_mount3:
5172         del_timer_sync(&sbi->s_err_report);
5173         if (sbi->s_mmp_tsk)
5174                 kthread_stop(sbi->s_mmp_tsk);
5175 failed_mount2:
5176         rcu_read_lock();
5177         group_desc = rcu_dereference(sbi->s_group_desc);
5178         for (i = 0; i < db_count; i++)
5179                 brelse(group_desc[i]);
5180         kvfree(group_desc);
5181         rcu_read_unlock();
5182 failed_mount:
5183         if (sbi->s_chksum_driver)
5184                 crypto_free_shash(sbi->s_chksum_driver);
5185
5186 #ifdef CONFIG_UNICODE
5187         utf8_unload(sbi->s_encoding);
5188 #endif
5189
5190 #ifdef CONFIG_QUOTA
5191         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5192                 kfree(get_qf_name(sb, sbi, i));
5193 #endif
5194         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5195         ext4_blkdev_remove(sbi);
5196         brelse(bh);
5197 out_fail:
5198         sb->s_fs_info = NULL;
5199         kfree(sbi->s_blockgroup_lock);
5200 out_free_base:
5201         kfree(sbi);
5202         kfree(orig_data);
5203         fs_put_dax(dax_dev);
5204         return err ? err : ret;
5205 }
5206
5207 /*
5208  * Setup any per-fs journal parameters now.  We'll do this both on
5209  * initial mount, once the journal has been initialised but before we've
5210  * done any recovery; and again on any subsequent remount.
5211  */
5212 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5213 {
5214         struct ext4_sb_info *sbi = EXT4_SB(sb);
5215
5216         journal->j_commit_interval = sbi->s_commit_interval;
5217         journal->j_min_batch_time = sbi->s_min_batch_time;
5218         journal->j_max_batch_time = sbi->s_max_batch_time;
5219         ext4_fc_init(sb, journal);
5220
5221         write_lock(&journal->j_state_lock);
5222         if (test_opt(sb, BARRIER))
5223                 journal->j_flags |= JBD2_BARRIER;
5224         else
5225                 journal->j_flags &= ~JBD2_BARRIER;
5226         if (test_opt(sb, DATA_ERR_ABORT))
5227                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5228         else
5229                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5230         write_unlock(&journal->j_state_lock);
5231 }
5232
5233 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5234                                              unsigned int journal_inum)
5235 {
5236         struct inode *journal_inode;
5237
5238         /*
5239          * Test for the existence of a valid inode on disk.  Bad things
5240          * happen if we iget() an unused inode, as the subsequent iput()
5241          * will try to delete it.
5242          */
5243         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5244         if (IS_ERR(journal_inode)) {
5245                 ext4_msg(sb, KERN_ERR, "no journal found");
5246                 return NULL;
5247         }
5248         if (!journal_inode->i_nlink) {
5249                 make_bad_inode(journal_inode);
5250                 iput(journal_inode);
5251                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5252                 return NULL;
5253         }
5254
5255         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
5256                   journal_inode, journal_inode->i_size);
5257         if (!S_ISREG(journal_inode->i_mode)) {
5258                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5259                 iput(journal_inode);
5260                 return NULL;
5261         }
5262         return journal_inode;
5263 }
5264
5265 static journal_t *ext4_get_journal(struct super_block *sb,
5266                                    unsigned int journal_inum)
5267 {
5268         struct inode *journal_inode;
5269         journal_t *journal;
5270
5271         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5272                 return NULL;
5273
5274         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5275         if (!journal_inode)
5276                 return NULL;
5277
5278         journal = jbd2_journal_init_inode(journal_inode);
5279         if (!journal) {
5280                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5281                 iput(journal_inode);
5282                 return NULL;
5283         }
5284         journal->j_private = sb;
5285         ext4_init_journal_params(sb, journal);
5286         return journal;
5287 }
5288
5289 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5290                                        dev_t j_dev)
5291 {
5292         struct buffer_head *bh;
5293         journal_t *journal;
5294         ext4_fsblk_t start;
5295         ext4_fsblk_t len;
5296         int hblock, blocksize;
5297         ext4_fsblk_t sb_block;
5298         unsigned long offset;
5299         struct ext4_super_block *es;
5300         struct block_device *bdev;
5301
5302         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5303                 return NULL;
5304
5305         bdev = ext4_blkdev_get(j_dev, sb);
5306         if (bdev == NULL)
5307                 return NULL;
5308
5309         blocksize = sb->s_blocksize;
5310         hblock = bdev_logical_block_size(bdev);
5311         if (blocksize < hblock) {
5312                 ext4_msg(sb, KERN_ERR,
5313                         "blocksize too small for journal device");
5314                 goto out_bdev;
5315         }
5316
5317         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5318         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5319         set_blocksize(bdev, blocksize);
5320         if (!(bh = __bread(bdev, sb_block, blocksize))) {
5321                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5322                        "external journal");
5323                 goto out_bdev;
5324         }
5325
5326         es = (struct ext4_super_block *) (bh->b_data + offset);
5327         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5328             !(le32_to_cpu(es->s_feature_incompat) &
5329               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5330                 ext4_msg(sb, KERN_ERR, "external journal has "
5331                                         "bad superblock");
5332                 brelse(bh);
5333                 goto out_bdev;
5334         }
5335
5336         if ((le32_to_cpu(es->s_feature_ro_compat) &
5337              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5338             es->s_checksum != ext4_superblock_csum(sb, es)) {
5339                 ext4_msg(sb, KERN_ERR, "external journal has "
5340                                        "corrupt superblock");
5341                 brelse(bh);
5342                 goto out_bdev;
5343         }
5344
5345         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5346                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5347                 brelse(bh);
5348                 goto out_bdev;
5349         }
5350
5351         len = ext4_blocks_count(es);
5352         start = sb_block + 1;
5353         brelse(bh);     /* we're done with the superblock */
5354
5355         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5356                                         start, len, blocksize);
5357         if (!journal) {
5358                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5359                 goto out_bdev;
5360         }
5361         journal->j_private = sb;
5362         if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
5363                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5364                 goto out_journal;
5365         }
5366         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5367                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5368                                         "user (unsupported) - %d",
5369                         be32_to_cpu(journal->j_superblock->s_nr_users));
5370                 goto out_journal;
5371         }
5372         EXT4_SB(sb)->s_journal_bdev = bdev;
5373         ext4_init_journal_params(sb, journal);
5374         return journal;
5375
5376 out_journal:
5377         jbd2_journal_destroy(journal);
5378 out_bdev:
5379         ext4_blkdev_put(bdev);
5380         return NULL;
5381 }
5382
5383 static int ext4_load_journal(struct super_block *sb,
5384                              struct ext4_super_block *es,
5385                              unsigned long journal_devnum)
5386 {
5387         journal_t *journal;
5388         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5389         dev_t journal_dev;
5390         int err = 0;
5391         int really_read_only;
5392         int journal_dev_ro;
5393
5394         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5395                 return -EFSCORRUPTED;
5396
5397         if (journal_devnum &&
5398             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5399                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5400                         "numbers have changed");
5401                 journal_dev = new_decode_dev(journal_devnum);
5402         } else
5403                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5404
5405         if (journal_inum && journal_dev) {
5406                 ext4_msg(sb, KERN_ERR,
5407                          "filesystem has both journal inode and journal device!");
5408                 return -EINVAL;
5409         }
5410
5411         if (journal_inum) {
5412                 journal = ext4_get_journal(sb, journal_inum);
5413                 if (!journal)
5414                         return -EINVAL;
5415         } else {
5416                 journal = ext4_get_dev_journal(sb, journal_dev);
5417                 if (!journal)
5418                         return -EINVAL;
5419         }
5420
5421         journal_dev_ro = bdev_read_only(journal->j_dev);
5422         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5423
5424         if (journal_dev_ro && !sb_rdonly(sb)) {
5425                 ext4_msg(sb, KERN_ERR,
5426                          "journal device read-only, try mounting with '-o ro'");
5427                 err = -EROFS;
5428                 goto err_out;
5429         }
5430
5431         /*
5432          * Are we loading a blank journal or performing recovery after a
5433          * crash?  For recovery, we need to check in advance whether we
5434          * can get read-write access to the device.
5435          */
5436         if (ext4_has_feature_journal_needs_recovery(sb)) {
5437                 if (sb_rdonly(sb)) {
5438                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5439                                         "required on readonly filesystem");
5440                         if (really_read_only) {
5441                                 ext4_msg(sb, KERN_ERR, "write access "
5442                                         "unavailable, cannot proceed "
5443                                         "(try mounting with noload)");
5444                                 err = -EROFS;
5445                                 goto err_out;
5446                         }
5447                         ext4_msg(sb, KERN_INFO, "write access will "
5448                                "be enabled during recovery");
5449                 }
5450         }
5451
5452         if (!(journal->j_flags & JBD2_BARRIER))
5453                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5454
5455         if (!ext4_has_feature_journal_needs_recovery(sb))
5456                 err = jbd2_journal_wipe(journal, !really_read_only);
5457         if (!err) {
5458                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5459                 if (save)
5460                         memcpy(save, ((char *) es) +
5461                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5462                 err = jbd2_journal_load(journal);
5463                 if (save)
5464                         memcpy(((char *) es) + EXT4_S_ERR_START,
5465                                save, EXT4_S_ERR_LEN);
5466                 kfree(save);
5467         }
5468
5469         if (err) {
5470                 ext4_msg(sb, KERN_ERR, "error loading journal");
5471                 goto err_out;
5472         }
5473
5474         EXT4_SB(sb)->s_journal = journal;
5475         err = ext4_clear_journal_err(sb, es);
5476         if (err) {
5477                 EXT4_SB(sb)->s_journal = NULL;
5478                 jbd2_journal_destroy(journal);
5479                 return err;
5480         }
5481
5482         if (!really_read_only && journal_devnum &&
5483             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5484                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5485
5486                 /* Make sure we flush the recovery flag to disk. */
5487                 ext4_commit_super(sb, 1);
5488         }
5489
5490         return 0;
5491
5492 err_out:
5493         jbd2_journal_destroy(journal);
5494         return err;
5495 }
5496
5497 static int ext4_commit_super(struct super_block *sb, int sync)
5498 {
5499         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
5500         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5501         int error = 0;
5502
5503         if (!sbh || block_device_ejected(sb))
5504                 return error;
5505
5506         /*
5507          * If the file system is mounted read-only, don't update the
5508          * superblock write time.  This avoids updating the superblock
5509          * write time when we are mounting the root file system
5510          * read/only but we need to replay the journal; at that point,
5511          * for people who are east of GMT and who make their clock
5512          * tick in localtime for Windows bug-for-bug compatibility,
5513          * the clock is set in the future, and this will cause e2fsck
5514          * to complain and force a full file system check.
5515          */
5516         if (!(sb->s_flags & SB_RDONLY))
5517                 ext4_update_tstamp(es, s_wtime);
5518         if (sb->s_bdev->bd_part)
5519                 es->s_kbytes_written =
5520                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5521                             ((part_stat_read(sb->s_bdev->bd_part,
5522                                              sectors[STAT_WRITE]) -
5523                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
5524         else
5525                 es->s_kbytes_written =
5526                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5527         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5528                 ext4_free_blocks_count_set(es,
5529                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5530                                 &EXT4_SB(sb)->s_freeclusters_counter)));
5531         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5532                 es->s_free_inodes_count =
5533                         cpu_to_le32(percpu_counter_sum_positive(
5534                                 &EXT4_SB(sb)->s_freeinodes_counter));
5535         BUFFER_TRACE(sbh, "marking dirty");
5536         ext4_superblock_csum_set(sb);
5537         if (sync)
5538                 lock_buffer(sbh);
5539         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5540                 /*
5541                  * Oh, dear.  A previous attempt to write the
5542                  * superblock failed.  This could happen because the
5543                  * USB device was yanked out.  Or it could happen to
5544                  * be a transient write error and maybe the block will
5545                  * be remapped.  Nothing we can do but to retry the
5546                  * write and hope for the best.
5547                  */
5548                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5549                        "superblock detected");
5550                 clear_buffer_write_io_error(sbh);
5551                 set_buffer_uptodate(sbh);
5552         }
5553         mark_buffer_dirty(sbh);
5554         if (sync) {
5555                 unlock_buffer(sbh);
5556                 error = __sync_dirty_buffer(sbh,
5557                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5558                 if (buffer_write_io_error(sbh)) {
5559                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5560                                "superblock");
5561                         clear_buffer_write_io_error(sbh);
5562                         set_buffer_uptodate(sbh);
5563                 }
5564         }
5565         return error;
5566 }
5567
5568 /*
5569  * Have we just finished recovery?  If so, and if we are mounting (or
5570  * remounting) the filesystem readonly, then we will end up with a
5571  * consistent fs on disk.  Record that fact.
5572  */
5573 static int ext4_mark_recovery_complete(struct super_block *sb,
5574                                        struct ext4_super_block *es)
5575 {
5576         int err;
5577         journal_t *journal = EXT4_SB(sb)->s_journal;
5578
5579         if (!ext4_has_feature_journal(sb)) {
5580                 if (journal != NULL) {
5581                         ext4_error(sb, "Journal got removed while the fs was "
5582                                    "mounted!");
5583                         return -EFSCORRUPTED;
5584                 }
5585                 return 0;
5586         }
5587         jbd2_journal_lock_updates(journal);
5588         err = jbd2_journal_flush(journal);
5589         if (err < 0)
5590                 goto out;
5591
5592         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5593                 ext4_clear_feature_journal_needs_recovery(sb);
5594                 ext4_commit_super(sb, 1);
5595         }
5596 out:
5597         jbd2_journal_unlock_updates(journal);
5598         return err;
5599 }
5600
5601 /*
5602  * If we are mounting (or read-write remounting) a filesystem whose journal
5603  * has recorded an error from a previous lifetime, move that error to the
5604  * main filesystem now.
5605  */
5606 static int ext4_clear_journal_err(struct super_block *sb,
5607                                    struct ext4_super_block *es)
5608 {
5609         journal_t *journal;
5610         int j_errno;
5611         const char *errstr;
5612
5613         if (!ext4_has_feature_journal(sb)) {
5614                 ext4_error(sb, "Journal got removed while the fs was mounted!");
5615                 return -EFSCORRUPTED;
5616         }
5617
5618         journal = EXT4_SB(sb)->s_journal;
5619
5620         /*
5621          * Now check for any error status which may have been recorded in the
5622          * journal by a prior ext4_error() or ext4_abort()
5623          */
5624
5625         j_errno = jbd2_journal_errno(journal);
5626         if (j_errno) {
5627                 char nbuf[16];
5628
5629                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5630                 ext4_warning(sb, "Filesystem error recorded "
5631                              "from previous mount: %s", errstr);
5632                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5633
5634                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5635                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5636                 ext4_commit_super(sb, 1);
5637
5638                 jbd2_journal_clear_err(journal);
5639                 jbd2_journal_update_sb_errno(journal);
5640         }
5641         return 0;
5642 }
5643
5644 /*
5645  * Force the running and committing transactions to commit,
5646  * and wait on the commit.
5647  */
5648 int ext4_force_commit(struct super_block *sb)
5649 {
5650         journal_t *journal;
5651
5652         if (sb_rdonly(sb))
5653                 return 0;
5654
5655         journal = EXT4_SB(sb)->s_journal;
5656         return ext4_journal_force_commit(journal);
5657 }
5658
5659 static int ext4_sync_fs(struct super_block *sb, int wait)
5660 {
5661         int ret = 0;
5662         tid_t target;
5663         bool needs_barrier = false;
5664         struct ext4_sb_info *sbi = EXT4_SB(sb);
5665
5666         if (unlikely(ext4_forced_shutdown(sbi)))
5667                 return 0;
5668
5669         trace_ext4_sync_fs(sb, wait);
5670         flush_workqueue(sbi->rsv_conversion_wq);
5671         /*
5672          * Writeback quota in non-journalled quota case - journalled quota has
5673          * no dirty dquots
5674          */
5675         dquot_writeback_dquots(sb, -1);
5676         /*
5677          * Data writeback is possible w/o journal transaction, so barrier must
5678          * being sent at the end of the function. But we can skip it if
5679          * transaction_commit will do it for us.
5680          */
5681         if (sbi->s_journal) {
5682                 target = jbd2_get_latest_transaction(sbi->s_journal);
5683                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5684                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5685                         needs_barrier = true;
5686
5687                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5688                         if (wait)
5689                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5690                                                            target);
5691                 }
5692         } else if (wait && test_opt(sb, BARRIER))
5693                 needs_barrier = true;
5694         if (needs_barrier) {
5695                 int err;
5696                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL);
5697                 if (!ret)
5698                         ret = err;
5699         }
5700
5701         return ret;
5702 }
5703
5704 /*
5705  * LVM calls this function before a (read-only) snapshot is created.  This
5706  * gives us a chance to flush the journal completely and mark the fs clean.
5707  *
5708  * Note that only this function cannot bring a filesystem to be in a clean
5709  * state independently. It relies on upper layer to stop all data & metadata
5710  * modifications.
5711  */
5712 static int ext4_freeze(struct super_block *sb)
5713 {
5714         int error = 0;
5715         journal_t *journal;
5716
5717         if (sb_rdonly(sb))
5718                 return 0;
5719
5720         journal = EXT4_SB(sb)->s_journal;
5721
5722         if (journal) {
5723                 /* Now we set up the journal barrier. */
5724                 jbd2_journal_lock_updates(journal);
5725
5726                 /*
5727                  * Don't clear the needs_recovery flag if we failed to
5728                  * flush the journal.
5729                  */
5730                 error = jbd2_journal_flush(journal);
5731                 if (error < 0)
5732                         goto out;
5733
5734                 /* Journal blocked and flushed, clear needs_recovery flag. */
5735                 ext4_clear_feature_journal_needs_recovery(sb);
5736         }
5737
5738         error = ext4_commit_super(sb, 1);
5739 out:
5740         if (journal)
5741                 /* we rely on upper layer to stop further updates */
5742                 jbd2_journal_unlock_updates(journal);
5743         return error;
5744 }
5745
5746 /*
5747  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5748  * flag here, even though the filesystem is not technically dirty yet.
5749  */
5750 static int ext4_unfreeze(struct super_block *sb)
5751 {
5752         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5753                 return 0;
5754
5755         if (EXT4_SB(sb)->s_journal) {
5756                 /* Reset the needs_recovery flag before the fs is unlocked. */
5757                 ext4_set_feature_journal_needs_recovery(sb);
5758         }
5759
5760         ext4_commit_super(sb, 1);
5761         return 0;
5762 }
5763
5764 /*
5765  * Structure to save mount options for ext4_remount's benefit
5766  */
5767 struct ext4_mount_options {
5768         unsigned long s_mount_opt;
5769         unsigned long s_mount_opt2;
5770         kuid_t s_resuid;
5771         kgid_t s_resgid;
5772         unsigned long s_commit_interval;
5773         u32 s_min_batch_time, s_max_batch_time;
5774 #ifdef CONFIG_QUOTA
5775         int s_jquota_fmt;
5776         char *s_qf_names[EXT4_MAXQUOTAS];
5777 #endif
5778 };
5779
5780 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5781 {
5782         struct ext4_super_block *es;
5783         struct ext4_sb_info *sbi = EXT4_SB(sb);
5784         unsigned long old_sb_flags, vfs_flags;
5785         struct ext4_mount_options old_opts;
5786         int enable_quota = 0;
5787         ext4_group_t g;
5788         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5789         int err = 0;
5790 #ifdef CONFIG_QUOTA
5791         int i, j;
5792         char *to_free[EXT4_MAXQUOTAS];
5793 #endif
5794         char *orig_data = kstrdup(data, GFP_KERNEL);
5795
5796         if (data && !orig_data)
5797                 return -ENOMEM;
5798
5799         /* Store the original options */
5800         old_sb_flags = sb->s_flags;
5801         old_opts.s_mount_opt = sbi->s_mount_opt;
5802         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5803         old_opts.s_resuid = sbi->s_resuid;
5804         old_opts.s_resgid = sbi->s_resgid;
5805         old_opts.s_commit_interval = sbi->s_commit_interval;
5806         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5807         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5808 #ifdef CONFIG_QUOTA
5809         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5810         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5811                 if (sbi->s_qf_names[i]) {
5812                         char *qf_name = get_qf_name(sb, sbi, i);
5813
5814                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5815                         if (!old_opts.s_qf_names[i]) {
5816                                 for (j = 0; j < i; j++)
5817                                         kfree(old_opts.s_qf_names[j]);
5818                                 kfree(orig_data);
5819                                 return -ENOMEM;
5820                         }
5821                 } else
5822                         old_opts.s_qf_names[i] = NULL;
5823 #endif
5824         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5825                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5826
5827         /*
5828          * Some options can be enabled by ext4 and/or by VFS mount flag
5829          * either way we need to make sure it matches in both *flags and
5830          * s_flags. Copy those selected flags from *flags to s_flags
5831          */
5832         vfs_flags = SB_LAZYTIME | SB_I_VERSION;
5833         sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags);
5834
5835         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5836                 err = -EINVAL;
5837                 goto restore_opts;
5838         }
5839
5840         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5841             test_opt(sb, JOURNAL_CHECKSUM)) {
5842                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5843                          "during remount not supported; ignoring");
5844                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5845         }
5846
5847         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5848                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5849                         ext4_msg(sb, KERN_ERR, "can't mount with "
5850                                  "both data=journal and delalloc");
5851                         err = -EINVAL;
5852                         goto restore_opts;
5853                 }
5854                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5855                         ext4_msg(sb, KERN_ERR, "can't mount with "
5856                                  "both data=journal and dioread_nolock");
5857                         err = -EINVAL;
5858                         goto restore_opts;
5859                 }
5860         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5861                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5862                         ext4_msg(sb, KERN_ERR, "can't mount with "
5863                                 "journal_async_commit in data=ordered mode");
5864                         err = -EINVAL;
5865                         goto restore_opts;
5866                 }
5867         }
5868
5869         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5870                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5871                 err = -EINVAL;
5872                 goto restore_opts;
5873         }
5874
5875         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5876                 ext4_abort(sb, EXT4_ERR_ESHUTDOWN, "Abort forced by user");
5877
5878         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5879                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5880
5881         es = sbi->s_es;
5882
5883         if (sbi->s_journal) {
5884                 ext4_init_journal_params(sb, sbi->s_journal);
5885                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5886         }
5887
5888         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5889                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5890                         err = -EROFS;
5891                         goto restore_opts;
5892                 }
5893
5894                 if (*flags & SB_RDONLY) {
5895                         err = sync_filesystem(sb);
5896                         if (err < 0)
5897                                 goto restore_opts;
5898                         err = dquot_suspend(sb, -1);
5899                         if (err < 0)
5900                                 goto restore_opts;
5901
5902                         /*
5903                          * First of all, the unconditional stuff we have to do
5904                          * to disable replay of the journal when we next remount
5905                          */
5906                         sb->s_flags |= SB_RDONLY;
5907
5908                         /*
5909                          * OK, test if we are remounting a valid rw partition
5910                          * readonly, and if so set the rdonly flag and then
5911                          * mark the partition as valid again.
5912                          */
5913                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5914                             (sbi->s_mount_state & EXT4_VALID_FS))
5915                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5916
5917                         if (sbi->s_journal) {
5918                                 /*
5919                                  * We let remount-ro finish even if marking fs
5920                                  * as clean failed...
5921                                  */
5922                                 ext4_mark_recovery_complete(sb, es);
5923                         }
5924                         if (sbi->s_mmp_tsk)
5925                                 kthread_stop(sbi->s_mmp_tsk);
5926                 } else {
5927                         /* Make sure we can mount this feature set readwrite */
5928                         if (ext4_has_feature_readonly(sb) ||
5929                             !ext4_feature_set_ok(sb, 0)) {
5930                                 err = -EROFS;
5931                                 goto restore_opts;
5932                         }
5933                         /*
5934                          * Make sure the group descriptor checksums
5935                          * are sane.  If they aren't, refuse to remount r/w.
5936                          */
5937                         for (g = 0; g < sbi->s_groups_count; g++) {
5938                                 struct ext4_group_desc *gdp =
5939                                         ext4_get_group_desc(sb, g, NULL);
5940
5941                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5942                                         ext4_msg(sb, KERN_ERR,
5943                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5944                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5945                                                le16_to_cpu(gdp->bg_checksum));
5946                                         err = -EFSBADCRC;
5947                                         goto restore_opts;
5948                                 }
5949                         }
5950
5951                         /*
5952                          * If we have an unprocessed orphan list hanging
5953                          * around from a previously readonly bdev mount,
5954                          * require a full umount/remount for now.
5955                          */
5956                         if (es->s_last_orphan) {
5957                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5958                                        "remount RDWR because of unprocessed "
5959                                        "orphan inode list.  Please "
5960                                        "umount/remount instead");
5961                                 err = -EINVAL;
5962                                 goto restore_opts;
5963                         }
5964
5965                         /*
5966                          * Mounting a RDONLY partition read-write, so reread
5967                          * and store the current valid flag.  (It may have
5968                          * been changed by e2fsck since we originally mounted
5969                          * the partition.)
5970                          */
5971                         if (sbi->s_journal) {
5972                                 err = ext4_clear_journal_err(sb, es);
5973                                 if (err)
5974                                         goto restore_opts;
5975                         }
5976                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5977
5978                         err = ext4_setup_super(sb, es, 0);
5979                         if (err)
5980                                 goto restore_opts;
5981
5982                         sb->s_flags &= ~SB_RDONLY;
5983                         if (ext4_has_feature_mmp(sb))
5984                                 if (ext4_multi_mount_protect(sb,
5985                                                 le64_to_cpu(es->s_mmp_block))) {
5986                                         err = -EROFS;
5987                                         goto restore_opts;
5988                                 }
5989                         enable_quota = 1;
5990                 }
5991         }
5992
5993         /*
5994          * Reinitialize lazy itable initialization thread based on
5995          * current settings
5996          */
5997         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5998                 ext4_unregister_li_request(sb);
5999         else {
6000                 ext4_group_t first_not_zeroed;
6001                 first_not_zeroed = ext4_has_uninit_itable(sb);
6002                 ext4_register_li_request(sb, first_not_zeroed);
6003         }
6004
6005         /*
6006          * Handle creation of system zone data early because it can fail.
6007          * Releasing of existing data is done when we are sure remount will
6008          * succeed.
6009          */
6010         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6011                 err = ext4_setup_system_zone(sb);
6012                 if (err)
6013                         goto restore_opts;
6014         }
6015
6016         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6017                 err = ext4_commit_super(sb, 1);
6018                 if (err)
6019                         goto restore_opts;
6020         }
6021
6022 #ifdef CONFIG_QUOTA
6023         /* Release old quota file names */
6024         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6025                 kfree(old_opts.s_qf_names[i]);
6026         if (enable_quota) {
6027                 if (sb_any_quota_suspended(sb))
6028                         dquot_resume(sb, -1);
6029                 else if (ext4_has_feature_quota(sb)) {
6030                         err = ext4_enable_quotas(sb);
6031                         if (err)
6032                                 goto restore_opts;
6033                 }
6034         }
6035 #endif
6036         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6037                 ext4_release_system_zone(sb);
6038
6039         /*
6040          * Some options can be enabled by ext4 and/or by VFS mount flag
6041          * either way we need to make sure it matches in both *flags and
6042          * s_flags. Copy those selected flags from s_flags to *flags
6043          */
6044         *flags = (*flags & ~vfs_flags) | (sb->s_flags & vfs_flags);
6045
6046         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
6047         kfree(orig_data);
6048         return 0;
6049
6050 restore_opts:
6051         sb->s_flags = old_sb_flags;
6052         sbi->s_mount_opt = old_opts.s_mount_opt;
6053         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6054         sbi->s_resuid = old_opts.s_resuid;
6055         sbi->s_resgid = old_opts.s_resgid;
6056         sbi->s_commit_interval = old_opts.s_commit_interval;
6057         sbi->s_min_batch_time = old_opts.s_min_batch_time;
6058         sbi->s_max_batch_time = old_opts.s_max_batch_time;
6059         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6060                 ext4_release_system_zone(sb);
6061 #ifdef CONFIG_QUOTA
6062         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6063         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6064                 to_free[i] = get_qf_name(sb, sbi, i);
6065                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6066         }
6067         synchronize_rcu();
6068         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6069                 kfree(to_free[i]);
6070 #endif
6071         kfree(orig_data);
6072         return err;
6073 }
6074
6075 #ifdef CONFIG_QUOTA
6076 static int ext4_statfs_project(struct super_block *sb,
6077                                kprojid_t projid, struct kstatfs *buf)
6078 {
6079         struct kqid qid;
6080         struct dquot *dquot;
6081         u64 limit;
6082         u64 curblock;
6083
6084         qid = make_kqid_projid(projid);
6085         dquot = dqget(sb, qid);
6086         if (IS_ERR(dquot))
6087                 return PTR_ERR(dquot);
6088         spin_lock(&dquot->dq_dqb_lock);
6089
6090         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6091                              dquot->dq_dqb.dqb_bhardlimit);
6092         limit >>= sb->s_blocksize_bits;
6093
6094         if (limit && buf->f_blocks > limit) {
6095                 curblock = (dquot->dq_dqb.dqb_curspace +
6096                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6097                 buf->f_blocks = limit;
6098                 buf->f_bfree = buf->f_bavail =
6099                         (buf->f_blocks > curblock) ?
6100                          (buf->f_blocks - curblock) : 0;
6101         }
6102
6103         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6104                              dquot->dq_dqb.dqb_ihardlimit);
6105         if (limit && buf->f_files > limit) {
6106                 buf->f_files = limit;
6107                 buf->f_ffree =
6108                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6109                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6110         }
6111
6112         spin_unlock(&dquot->dq_dqb_lock);
6113         dqput(dquot);
6114         return 0;
6115 }
6116 #endif
6117
6118 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6119 {
6120         struct super_block *sb = dentry->d_sb;
6121         struct ext4_sb_info *sbi = EXT4_SB(sb);
6122         struct ext4_super_block *es = sbi->s_es;
6123         ext4_fsblk_t overhead = 0, resv_blocks;
6124         u64 fsid;
6125         s64 bfree;
6126         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6127
6128         if (!test_opt(sb, MINIX_DF))
6129                 overhead = sbi->s_overhead;
6130
6131         buf->f_type = EXT4_SUPER_MAGIC;
6132         buf->f_bsize = sb->s_blocksize;
6133         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6134         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6135                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6136         /* prevent underflow in case that few free space is available */
6137         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6138         buf->f_bavail = buf->f_bfree -
6139                         (ext4_r_blocks_count(es) + resv_blocks);
6140         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6141                 buf->f_bavail = 0;
6142         buf->f_files = le32_to_cpu(es->s_inodes_count);
6143         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6144         buf->f_namelen = EXT4_NAME_LEN;
6145         fsid = le64_to_cpup((void *)es->s_uuid) ^
6146                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
6147         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
6148         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
6149
6150 #ifdef CONFIG_QUOTA
6151         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6152             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6153                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6154 #endif
6155         return 0;
6156 }
6157
6158
6159 #ifdef CONFIG_QUOTA
6160
6161 /*
6162  * Helper functions so that transaction is started before we acquire dqio_sem
6163  * to keep correct lock ordering of transaction > dqio_sem
6164  */
6165 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6166 {
6167         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6168 }
6169
6170 static int ext4_write_dquot(struct dquot *dquot)
6171 {
6172         int ret, err;
6173         handle_t *handle;
6174         struct inode *inode;
6175
6176         inode = dquot_to_inode(dquot);
6177         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6178                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6179         if (IS_ERR(handle))
6180                 return PTR_ERR(handle);
6181         ret = dquot_commit(dquot);
6182         err = ext4_journal_stop(handle);
6183         if (!ret)
6184                 ret = err;
6185         return ret;
6186 }
6187
6188 static int ext4_acquire_dquot(struct dquot *dquot)
6189 {
6190         int ret, err;
6191         handle_t *handle;
6192
6193         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6194                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6195         if (IS_ERR(handle))
6196                 return PTR_ERR(handle);
6197         ret = dquot_acquire(dquot);
6198         err = ext4_journal_stop(handle);
6199         if (!ret)
6200                 ret = err;
6201         return ret;
6202 }
6203
6204 static int ext4_release_dquot(struct dquot *dquot)
6205 {
6206         int ret, err;
6207         handle_t *handle;
6208
6209         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6210                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6211         if (IS_ERR(handle)) {
6212                 /* Release dquot anyway to avoid endless cycle in dqput() */
6213                 dquot_release(dquot);
6214                 return PTR_ERR(handle);
6215         }
6216         ret = dquot_release(dquot);
6217         err = ext4_journal_stop(handle);
6218         if (!ret)
6219                 ret = err;
6220         return ret;
6221 }
6222
6223 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6224 {
6225         struct super_block *sb = dquot->dq_sb;
6226         struct ext4_sb_info *sbi = EXT4_SB(sb);
6227
6228         /* Are we journaling quotas? */
6229         if (ext4_has_feature_quota(sb) ||
6230             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
6231                 dquot_mark_dquot_dirty(dquot);
6232                 return ext4_write_dquot(dquot);
6233         } else {
6234                 return dquot_mark_dquot_dirty(dquot);
6235         }
6236 }
6237
6238 static int ext4_write_info(struct super_block *sb, int type)
6239 {
6240         int ret, err;
6241         handle_t *handle;
6242
6243         /* Data block + inode block */
6244         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
6245         if (IS_ERR(handle))
6246                 return PTR_ERR(handle);
6247         ret = dquot_commit_info(sb, type);
6248         err = ext4_journal_stop(handle);
6249         if (!ret)
6250                 ret = err;
6251         return ret;
6252 }
6253
6254 /*
6255  * Turn on quotas during mount time - we need to find
6256  * the quota file and such...
6257  */
6258 static int ext4_quota_on_mount(struct super_block *sb, int type)
6259 {
6260         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
6261                                         EXT4_SB(sb)->s_jquota_fmt, type);
6262 }
6263
6264 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6265 {
6266         struct ext4_inode_info *ei = EXT4_I(inode);
6267
6268         /* The first argument of lockdep_set_subclass has to be
6269          * *exactly* the same as the argument to init_rwsem() --- in
6270          * this case, in init_once() --- or lockdep gets unhappy
6271          * because the name of the lock is set using the
6272          * stringification of the argument to init_rwsem().
6273          */
6274         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6275         lockdep_set_subclass(&ei->i_data_sem, subclass);
6276 }
6277
6278 /*
6279  * Standard function to be called on quota_on
6280  */
6281 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6282                          const struct path *path)
6283 {
6284         int err;
6285
6286         if (!test_opt(sb, QUOTA))
6287                 return -EINVAL;
6288
6289         /* Quotafile not on the same filesystem? */
6290         if (path->dentry->d_sb != sb)
6291                 return -EXDEV;
6292
6293         /* Quota already enabled for this file? */
6294         if (IS_NOQUOTA(d_inode(path->dentry)))
6295                 return -EBUSY;
6296
6297         /* Journaling quota? */
6298         if (EXT4_SB(sb)->s_qf_names[type]) {
6299                 /* Quotafile not in fs root? */
6300                 if (path->dentry->d_parent != sb->s_root)
6301                         ext4_msg(sb, KERN_WARNING,
6302                                 "Quota file not on filesystem root. "
6303                                 "Journaled quota will not work");
6304                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6305         } else {
6306                 /*
6307                  * Clear the flag just in case mount options changed since
6308                  * last time.
6309                  */
6310                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6311         }
6312
6313         /*
6314          * When we journal data on quota file, we have to flush journal to see
6315          * all updates to the file when we bypass pagecache...
6316          */
6317         if (EXT4_SB(sb)->s_journal &&
6318             ext4_should_journal_data(d_inode(path->dentry))) {
6319                 /*
6320                  * We don't need to lock updates but journal_flush() could
6321                  * otherwise be livelocked...
6322                  */
6323                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6324                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
6325                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6326                 if (err)
6327                         return err;
6328         }
6329
6330         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6331         err = dquot_quota_on(sb, type, format_id, path);
6332         if (err) {
6333                 lockdep_set_quota_inode(path->dentry->d_inode,
6334                                              I_DATA_SEM_NORMAL);
6335         } else {
6336                 struct inode *inode = d_inode(path->dentry);
6337                 handle_t *handle;
6338
6339                 /*
6340                  * Set inode flags to prevent userspace from messing with quota
6341                  * files. If this fails, we return success anyway since quotas
6342                  * are already enabled and this is not a hard failure.
6343                  */
6344                 inode_lock(inode);
6345                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6346                 if (IS_ERR(handle))
6347                         goto unlock_inode;
6348                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6349                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6350                                 S_NOATIME | S_IMMUTABLE);
6351                 err = ext4_mark_inode_dirty(handle, inode);
6352                 ext4_journal_stop(handle);
6353         unlock_inode:
6354                 inode_unlock(inode);
6355         }
6356         return err;
6357 }
6358
6359 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6360                              unsigned int flags)
6361 {
6362         int err;
6363         struct inode *qf_inode;
6364         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6365                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6366                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6367                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6368         };
6369
6370         BUG_ON(!ext4_has_feature_quota(sb));
6371
6372         if (!qf_inums[type])
6373                 return -EPERM;
6374
6375         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6376         if (IS_ERR(qf_inode)) {
6377                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6378                 return PTR_ERR(qf_inode);
6379         }
6380
6381         /* Don't account quota for quota files to avoid recursion */
6382         qf_inode->i_flags |= S_NOQUOTA;
6383         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6384         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6385         if (err)
6386                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6387         iput(qf_inode);
6388
6389         return err;
6390 }
6391
6392 /* Enable usage tracking for all quota types. */
6393 static int ext4_enable_quotas(struct super_block *sb)
6394 {
6395         int type, err = 0;
6396         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6397                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6398                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6399                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6400         };
6401         bool quota_mopt[EXT4_MAXQUOTAS] = {
6402                 test_opt(sb, USRQUOTA),
6403                 test_opt(sb, GRPQUOTA),
6404                 test_opt(sb, PRJQUOTA),
6405         };
6406
6407         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6408         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6409                 if (qf_inums[type]) {
6410                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6411                                 DQUOT_USAGE_ENABLED |
6412                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6413                         if (err) {
6414                                 ext4_warning(sb,
6415                                         "Failed to enable quota tracking "
6416                                         "(type=%d, err=%d). Please run "
6417                                         "e2fsck to fix.", type, err);
6418                                 for (type--; type >= 0; type--)
6419                                         dquot_quota_off(sb, type);
6420
6421                                 return err;
6422                         }
6423                 }
6424         }
6425         return 0;
6426 }
6427
6428 static int ext4_quota_off(struct super_block *sb, int type)
6429 {
6430         struct inode *inode = sb_dqopt(sb)->files[type];
6431         handle_t *handle;
6432         int err;
6433
6434         /* Force all delayed allocation blocks to be allocated.
6435          * Caller already holds s_umount sem */
6436         if (test_opt(sb, DELALLOC))
6437                 sync_filesystem(sb);
6438
6439         if (!inode || !igrab(inode))
6440                 goto out;
6441
6442         err = dquot_quota_off(sb, type);
6443         if (err || ext4_has_feature_quota(sb))
6444                 goto out_put;
6445
6446         inode_lock(inode);
6447         /*
6448          * Update modification times of quota files when userspace can
6449          * start looking at them. If we fail, we return success anyway since
6450          * this is not a hard failure and quotas are already disabled.
6451          */
6452         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6453         if (IS_ERR(handle)) {
6454                 err = PTR_ERR(handle);
6455                 goto out_unlock;
6456         }
6457         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6458         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6459         inode->i_mtime = inode->i_ctime = current_time(inode);
6460         err = ext4_mark_inode_dirty(handle, inode);
6461         ext4_journal_stop(handle);
6462 out_unlock:
6463         inode_unlock(inode);
6464 out_put:
6465         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6466         iput(inode);
6467         return err;
6468 out:
6469         return dquot_quota_off(sb, type);
6470 }
6471
6472 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6473  * acquiring the locks... As quota files are never truncated and quota code
6474  * itself serializes the operations (and no one else should touch the files)
6475  * we don't have to be afraid of races */
6476 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6477                                size_t len, loff_t off)
6478 {
6479         struct inode *inode = sb_dqopt(sb)->files[type];
6480         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6481         int offset = off & (sb->s_blocksize - 1);
6482         int tocopy;
6483         size_t toread;
6484         struct buffer_head *bh;
6485         loff_t i_size = i_size_read(inode);
6486
6487         if (off > i_size)
6488                 return 0;
6489         if (off+len > i_size)
6490                 len = i_size-off;
6491         toread = len;
6492         while (toread > 0) {
6493                 tocopy = sb->s_blocksize - offset < toread ?
6494                                 sb->s_blocksize - offset : toread;
6495                 bh = ext4_bread(NULL, inode, blk, 0);
6496                 if (IS_ERR(bh))
6497                         return PTR_ERR(bh);
6498                 if (!bh)        /* A hole? */
6499                         memset(data, 0, tocopy);
6500                 else
6501                         memcpy(data, bh->b_data+offset, tocopy);
6502                 brelse(bh);
6503                 offset = 0;
6504                 toread -= tocopy;
6505                 data += tocopy;
6506                 blk++;
6507         }
6508         return len;
6509 }
6510
6511 /* Write to quotafile (we know the transaction is already started and has
6512  * enough credits) */
6513 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6514                                 const char *data, size_t len, loff_t off)
6515 {
6516         struct inode *inode = sb_dqopt(sb)->files[type];
6517         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6518         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6519         int retries = 0;
6520         struct buffer_head *bh;
6521         handle_t *handle = journal_current_handle();
6522
6523         if (EXT4_SB(sb)->s_journal && !handle) {
6524                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6525                         " cancelled because transaction is not started",
6526                         (unsigned long long)off, (unsigned long long)len);
6527                 return -EIO;
6528         }
6529         /*
6530          * Since we account only one data block in transaction credits,
6531          * then it is impossible to cross a block boundary.
6532          */
6533         if (sb->s_blocksize - offset < len) {
6534                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6535                         " cancelled because not block aligned",
6536                         (unsigned long long)off, (unsigned long long)len);
6537                 return -EIO;
6538         }
6539
6540         do {
6541                 bh = ext4_bread(handle, inode, blk,
6542                                 EXT4_GET_BLOCKS_CREATE |
6543                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6544         } while (PTR_ERR(bh) == -ENOSPC &&
6545                  ext4_should_retry_alloc(inode->i_sb, &retries));
6546         if (IS_ERR(bh))
6547                 return PTR_ERR(bh);
6548         if (!bh)
6549                 goto out;
6550         BUFFER_TRACE(bh, "get write access");
6551         err = ext4_journal_get_write_access(handle, bh);
6552         if (err) {
6553                 brelse(bh);
6554                 return err;
6555         }
6556         lock_buffer(bh);
6557         memcpy(bh->b_data+offset, data, len);
6558         flush_dcache_page(bh->b_page);
6559         unlock_buffer(bh);
6560         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6561         brelse(bh);
6562 out:
6563         if (inode->i_size < off + len) {
6564                 ext4_fc_track_range(inode,
6565                         (inode->i_size > 0 ? inode->i_size - 1 : 0)
6566                                 >> inode->i_sb->s_blocksize_bits,
6567                         (off + len) >> inode->i_sb->s_blocksize_bits);
6568                 i_size_write(inode, off + len);
6569                 EXT4_I(inode)->i_disksize = inode->i_size;
6570                 err2 = ext4_mark_inode_dirty(handle, inode);
6571                 if (unlikely(err2 && !err))
6572                         err = err2;
6573         }
6574         return err ? err : len;
6575 }
6576 #endif
6577
6578 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6579                        const char *dev_name, void *data)
6580 {
6581         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6582 }
6583
6584 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6585 static inline void register_as_ext2(void)
6586 {
6587         int err = register_filesystem(&ext2_fs_type);
6588         if (err)
6589                 printk(KERN_WARNING
6590                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6591 }
6592
6593 static inline void unregister_as_ext2(void)
6594 {
6595         unregister_filesystem(&ext2_fs_type);
6596 }
6597
6598 static inline int ext2_feature_set_ok(struct super_block *sb)
6599 {
6600         if (ext4_has_unknown_ext2_incompat_features(sb))
6601                 return 0;
6602         if (sb_rdonly(sb))
6603                 return 1;
6604         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6605                 return 0;
6606         return 1;
6607 }
6608 #else
6609 static inline void register_as_ext2(void) { }
6610 static inline void unregister_as_ext2(void) { }
6611 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6612 #endif
6613
6614 static inline void register_as_ext3(void)
6615 {
6616         int err = register_filesystem(&ext3_fs_type);
6617         if (err)
6618                 printk(KERN_WARNING
6619                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6620 }
6621
6622 static inline void unregister_as_ext3(void)
6623 {
6624         unregister_filesystem(&ext3_fs_type);
6625 }
6626
6627 static inline int ext3_feature_set_ok(struct super_block *sb)
6628 {
6629         if (ext4_has_unknown_ext3_incompat_features(sb))
6630                 return 0;
6631         if (!ext4_has_feature_journal(sb))
6632                 return 0;
6633         if (sb_rdonly(sb))
6634                 return 1;
6635         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6636                 return 0;
6637         return 1;
6638 }
6639
6640 static struct file_system_type ext4_fs_type = {
6641         .owner          = THIS_MODULE,
6642         .name           = "ext4",
6643         .mount          = ext4_mount,
6644         .kill_sb        = kill_block_super,
6645         .fs_flags       = FS_REQUIRES_DEV,
6646 };
6647 MODULE_ALIAS_FS("ext4");
6648
6649 /* Shared across all ext4 file systems */
6650 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6651
6652 static int __init ext4_init_fs(void)
6653 {
6654         int i, err;
6655
6656         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6657         ext4_li_info = NULL;
6658         mutex_init(&ext4_li_mtx);
6659
6660         /* Build-time check for flags consistency */
6661         ext4_check_flag_values();
6662
6663         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6664                 init_waitqueue_head(&ext4__ioend_wq[i]);
6665
6666         err = ext4_init_es();
6667         if (err)
6668                 return err;
6669
6670         err = ext4_init_pending();
6671         if (err)
6672                 goto out7;
6673
6674         err = ext4_init_post_read_processing();
6675         if (err)
6676                 goto out6;
6677
6678         err = ext4_init_pageio();
6679         if (err)
6680                 goto out5;
6681
6682         err = ext4_init_system_zone();
6683         if (err)
6684                 goto out4;
6685
6686         err = ext4_init_sysfs();
6687         if (err)
6688                 goto out3;
6689
6690         err = ext4_init_mballoc();
6691         if (err)
6692                 goto out2;
6693         err = init_inodecache();
6694         if (err)
6695                 goto out1;
6696
6697         err = ext4_fc_init_dentry_cache();
6698         if (err)
6699                 goto out05;
6700
6701         register_as_ext3();
6702         register_as_ext2();
6703         err = register_filesystem(&ext4_fs_type);
6704         if (err)
6705                 goto out;
6706
6707         return 0;
6708 out:
6709         unregister_as_ext2();
6710         unregister_as_ext3();
6711 out05:
6712         destroy_inodecache();
6713 out1:
6714         ext4_exit_mballoc();
6715 out2:
6716         ext4_exit_sysfs();
6717 out3:
6718         ext4_exit_system_zone();
6719 out4:
6720         ext4_exit_pageio();
6721 out5:
6722         ext4_exit_post_read_processing();
6723 out6:
6724         ext4_exit_pending();
6725 out7:
6726         ext4_exit_es();
6727
6728         return err;
6729 }
6730
6731 static void __exit ext4_exit_fs(void)
6732 {
6733         ext4_destroy_lazyinit_thread();
6734         unregister_as_ext2();
6735         unregister_as_ext3();
6736         unregister_filesystem(&ext4_fs_type);
6737         destroy_inodecache();
6738         ext4_exit_mballoc();
6739         ext4_exit_sysfs();
6740         ext4_exit_system_zone();
6741         ext4_exit_pageio();
6742         ext4_exit_post_read_processing();
6743         ext4_exit_es();
6744         ext4_exit_pending();
6745 }
6746
6747 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6748 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6749 MODULE_LICENSE("GPL");
6750 MODULE_SOFTDEP("pre: crc32c");
6751 module_init(ext4_init_fs)
6752 module_exit(ext4_exit_fs)