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 static bool system_going_down(void)
 575 {
 576         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 577                 || system_state == SYSTEM_RESTART;
 578 }
 579
 580 /* Deal with the reporting of failure conditions on a filesystem such as
 581  * inconsistencies detected or read IO failures.
 582  *
 583  * On ext2, we can store the error state of the filesystem in the
 584  * superblock.  That is not possible on ext4, because we may have other
 585  * write ordering constraints on the superblock which prevent us from
 586  * writing it out straight away; and given that the journal is about to
 587  * be aborted, we can't rely on the current, or future, transactions to
 588  * write out the superblock safely.
 589  *
 590  * We'll just use the jbd2_journal_abort() error code to record an error in
 591  * the journal instead.  On recovery, the journal will complain about
 592  * that error until we've noted it down and cleared it.
 593  */
 594
 595 static void ext4_handle_error(struct super_block *sb)
 596 {
 597         if (test_opt(sb, WARN_ON_ERROR))
 598                 WARN_ON_ONCE(1);
 599
 600         if (sb_rdonly(sb))
 601                 return;
 602
 603         if (!test_opt(sb, ERRORS_CONT)) {
 604                 journal_t *journal = EXT4_SB(sb)->s_journal;
 605
 606                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 607                 if (journal)
 608                         jbd2_journal_abort(journal, -EIO);
 609         }
 610         /*
 611          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 612          * could panic during 'reboot -f' as the underlying device got already
 613          * disabled.
 614          */
 615         if (test_opt(sb, ERRORS_RO) || system_going_down()) {
 616                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 617                 /*
 618                  * Make sure updated value of ->s_mount_flags will be visible
 619                  * before ->s_flags update
 620                  */
 621                 smp_wmb();
 622                 sb->s_flags |= SB_RDONLY;
 623         } else if (test_opt(sb, ERRORS_PANIC)) {
 624                 panic("EXT4-fs (device %s): panic forced after error\n",
 625                         sb->s_id);
 626         }
 627 }
 628
 629 #define ext4_error_ratelimit(sb)                                        \
 630                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 631                              "EXT4-fs error")
 632
 633 void __ext4_error(struct super_block *sb, const char *function,
 634                   unsigned int line, int error, __u64 block,
 635                   const char *fmt, ...)
 636 {
 637         struct va_format vaf;
 638         va_list args;
 639
 640         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 641                 return;
 642
 643         trace_ext4_error(sb, function, line);
 644         if (ext4_error_ratelimit(sb)) {
 645                 va_start(args, fmt);
 646                 vaf.fmt = fmt;
 647                 vaf.va = &args;
 648                 printk(KERN_CRIT
 649                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 650                        sb->s_id, function, line, current->comm, &vaf);
 651                 va_end(args);
 652         }
 653         save_error_info(sb, error, 0, block, function, line);
 654         ext4_handle_error(sb);
 655 }
 656
 657 void __ext4_error_inode(struct inode *inode, const char *function,
 658                         unsigned int line, ext4_fsblk_t block, int error,
 659                         const char *fmt, ...)
 660 {
 661         va_list args;
 662         struct va_format vaf;
 663
 664         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 665                 return;
 666
 667         trace_ext4_error(inode->i_sb, function, line);
 668         if (ext4_error_ratelimit(inode->i_sb)) {
 669                 va_start(args, fmt);
 670                 vaf.fmt = fmt;
 671                 vaf.va = &args;
 672                 if (block)
 673                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 674                                "inode #%lu: block %llu: comm %s: %pV\n",
 675                                inode->i_sb->s_id, function, line, inode->i_ino,
 676                                block, current->comm, &vaf);
 677                 else
 678                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 679                                "inode #%lu: comm %s: %pV\n",
 680                                inode->i_sb->s_id, function, line, inode->i_ino,
 681                                current->comm, &vaf);
 682                 va_end(args);
 683         }
 684         save_error_info(inode->i_sb, error, inode->i_ino, block,
 685                         function, line);
 686         ext4_handle_error(inode->i_sb);
 687 }
 688
 689 void __ext4_error_file(struct file *file, const char *function,
 690                        unsigned int line, ext4_fsblk_t block,
 691                        const char *fmt, ...)
 692 {
 693         va_list args;
 694         struct va_format vaf;
 695         struct inode *inode = file_inode(file);
 696         char pathname[80], *path;
 697
 698         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 699                 return;
 700
 701         trace_ext4_error(inode->i_sb, function, line);
 702         if (ext4_error_ratelimit(inode->i_sb)) {
 703                 path = file_path(file, pathname, sizeof(pathname));
 704                 if (IS_ERR(path))
 705                         path = "(unknown)";
 706                 va_start(args, fmt);
 707                 vaf.fmt = fmt;
 708                 vaf.va = &args;
 709                 if (block)
 710                         printk(KERN_CRIT
 711                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 712                                "block %llu: comm %s: path %s: %pV\n",
 713                                inode->i_sb->s_id, function, line, inode->i_ino,
 714                                block, current->comm, path, &vaf);
 715                 else
 716                         printk(KERN_CRIT
 717                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 718                                "comm %s: path %s: %pV\n",
 719                                inode->i_sb->s_id, function, line, inode->i_ino,
 720                                current->comm, path, &vaf);
 721                 va_end(args);
 722         }
 723         save_error_info(inode->i_sb, EFSCORRUPTED, inode->i_ino, block,
 724                         function, line);
 725         ext4_handle_error(inode->i_sb);
 726 }
 727
 728 const char *ext4_decode_error(struct super_block *sb, int errno,
 729                               char nbuf[16])
 730 {
 731         char *errstr = NULL;
 732
 733         switch (errno) {
 734         case -EFSCORRUPTED:
 735                 errstr = "Corrupt filesystem";
 736                 break;
 737         case -EFSBADCRC:
 738                 errstr = "Filesystem failed CRC";
 739                 break;
 740         case -EIO:
 741                 errstr = "IO failure";
 742                 break;
 743         case -ENOMEM:
 744                 errstr = "Out of memory";
 745                 break;
 746         case -EROFS:
 747                 if (!sb || (EXT4_SB(sb)->s_journal &&
 748                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 749                         errstr = "Journal has aborted";
 750                 else
 751                         errstr = "Readonly filesystem";
 752                 break;
 753         default:
 754                 /* If the caller passed in an extra buffer for unknown
 755                  * errors, textualise them now.  Else we just return
 756                  * NULL. */
 757                 if (nbuf) {
 758                         /* Check for truncated error codes... */
 759                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 760                                 errstr = nbuf;
 761                 }
 762                 break;
 763         }
 764
 765         return errstr;
 766 }
 767
 768 /* __ext4_std_error decodes expected errors from journaling functions
 769  * automatically and invokes the appropriate error response.  */
 770
 771 void __ext4_std_error(struct super_block *sb, const char *function,
 772                       unsigned int line, int errno)
 773 {
 774         char nbuf[16];
 775         const char *errstr;
 776
 777         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 778                 return;
 779
 780         /* Special case: if the error is EROFS, and we're not already
 781          * inside a transaction, then there's really no point in logging
 782          * an error. */
 783         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 784                 return;
 785
 786         if (ext4_error_ratelimit(sb)) {
 787                 errstr = ext4_decode_error(sb, errno, nbuf);
 788                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 789                        sb->s_id, function, line, errstr);
 790         }
 791
 792         save_error_info(sb, -errno, 0, 0, function, line);
 793         ext4_handle_error(sb);
 794 }
 795
 796 /*
 797  * ext4_abort is a much stronger failure handler than ext4_error.  The
 798  * abort function may be used to deal with unrecoverable failures such
 799  * as journal IO errors or ENOMEM at a critical moment in log management.
 800  *
 801  * We unconditionally force the filesystem into an ABORT|READONLY state,
 802  * unless the error response on the fs has been set to panic in which
 803  * case we take the easy way out and panic immediately.
 804  */
 805
 806 void __ext4_abort(struct super_block *sb, const char *function,
 807                   unsigned int line, int error, const char *fmt, ...)
 808 {
 809         struct va_format vaf;
 810         va_list args;
 811
 812         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 813                 return;
 814
 815         save_error_info(sb, error, 0, 0, function, line);
 816         va_start(args, fmt);
 817         vaf.fmt = fmt;
 818         vaf.va = &args;
 819         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 820                sb->s_id, function, line, &vaf);
 821         va_end(args);
 822
 823         if (sb_rdonly(sb) == 0) {
 824                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 825                 if (EXT4_SB(sb)->s_journal)
 826                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 827
 828                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 829                 /*
 830                  * Make sure updated value of ->s_mount_flags will be visible
 831                  * before ->s_flags update
 832                  */
 833                 smp_wmb();
 834                 sb->s_flags |= SB_RDONLY;
 835         }
 836         if (test_opt(sb, ERRORS_PANIC) && !system_going_down())
 837                 panic("EXT4-fs panic from previous error\n");
 838 }
 839
 840 void __ext4_msg(struct super_block *sb,
 841                 const char *prefix, const char *fmt, ...)
 842 {
 843         struct va_format vaf;
 844         va_list args;
 845
 846         atomic_inc(&EXT4_SB(sb)->s_msg_count);
 847         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 848                 return;
 849
 850         va_start(args, fmt);
 851         vaf.fmt = fmt;
 852         vaf.va = &args;
 853         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 854         va_end(args);
 855 }
 856
 857 static int ext4_warning_ratelimit(struct super_block *sb)
 858 {
 859         atomic_inc(&EXT4_SB(sb)->s_warning_count);
 860         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
 861                             "EXT4-fs warning");
 862 }
 863
 864 void __ext4_warning(struct super_block *sb, const char *function,
 865                     unsigned int line, const char *fmt, ...)
 866 {
 867         struct va_format vaf;
 868         va_list args;
 869
 870         if (!ext4_warning_ratelimit(sb))
 871                 return;
 872
 873         va_start(args, fmt);
 874         vaf.fmt = fmt;
 875         vaf.va = &args;
 876         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 877                sb->s_id, function, line, &vaf);
 878         va_end(args);
 879 }
 880
 881 void __ext4_warning_inode(const struct inode *inode, const char *function,
 882                           unsigned int line, const char *fmt, ...)
 883 {
 884         struct va_format vaf;
 885         va_list args;
 886
 887         if (!ext4_warning_ratelimit(inode->i_sb))
 888                 return;
 889
 890         va_start(args, fmt);
 891         vaf.fmt = fmt;
 892         vaf.va = &args;
 893         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 894                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 895                function, line, inode->i_ino, current->comm, &vaf);
 896         va_end(args);
 897 }
 898
 899 void __ext4_grp_locked_error(const char *function, unsigned int line,
 900                              struct super_block *sb, ext4_group_t grp,
 901                              unsigned long ino, ext4_fsblk_t block,
 902                              const char *fmt, ...)
 903 __releases(bitlock)
 904 __acquires(bitlock)
 905 {
 906         struct va_format vaf;
 907         va_list args;
 908
 909         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 910                 return;
 911
 912         trace_ext4_error(sb, function, line);
 913         __save_error_info(sb, EFSCORRUPTED, ino, block, function, line);
 914
 915         if (ext4_error_ratelimit(sb)) {
 916                 va_start(args, fmt);
 917                 vaf.fmt = fmt;
 918                 vaf.va = &args;
 919                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 920                        sb->s_id, function, line, grp);
 921                 if (ino)
 922                         printk(KERN_CONT "inode %lu: ", ino);
 923                 if (block)
 924                         printk(KERN_CONT "block %llu:",
 925                                (unsigned long long) block);
 926                 printk(KERN_CONT "%pV\n", &vaf);
 927                 va_end(args);
 928         }
 929
 930         if (test_opt(sb, WARN_ON_ERROR))
 931                 WARN_ON_ONCE(1);
 932
 933         if (test_opt(sb, ERRORS_CONT)) {
 934                 ext4_commit_super(sb, 0);
 935                 return;
 936         }
 937
 938         ext4_unlock_group(sb, grp);
 939         ext4_commit_super(sb, 1);
 940         ext4_handle_error(sb);
 941         /*
 942          * We only get here in the ERRORS_RO case; relocking the group
 943          * may be dangerous, but nothing bad will happen since the
 944          * filesystem will have already been marked read/only and the
 945          * journal has been aborted.  We return 1 as a hint to callers
 946          * who might what to use the return value from
 947          * ext4_grp_locked_error() to distinguish between the
 948          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 949          * aggressively from the ext4 function in question, with a
 950          * more appropriate error code.
 951          */
 952         ext4_lock_group(sb, grp);
 953         return;
 954 }
 955
 956 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
 957                                      ext4_group_t group,
 958                                      unsigned int flags)
 959 {
 960         struct ext4_sb_info *sbi = EXT4_SB(sb);
 961         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
 962         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
 963         int ret;
 964
 965         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
 966                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
 967                                             &grp->bb_state);
 968                 if (!ret)
 969                         percpu_counter_sub(&sbi->s_freeclusters_counter,
 970                                            grp->bb_free);
 971         }
 972
 973         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
 974                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
 975                                             &grp->bb_state);
 976                 if (!ret && gdp) {
 977                         int count;
 978
 979                         count = ext4_free_inodes_count(sb, gdp);
 980                         percpu_counter_sub(&sbi->s_freeinodes_counter,
 981                                            count);
 982                 }
 983         }
 984 }
 985
 986 void ext4_update_dynamic_rev(struct super_block *sb)
 987 {
 988         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 989
 990         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 991                 return;
 992
 993         ext4_warning(sb,
 994                      "updating to rev %d because of new feature flag, "
 995                      "running e2fsck is recommended",
 996                      EXT4_DYNAMIC_REV);
 997
 998         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 999         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1000         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1001         /* leave es->s_feature_*compat flags alone */
1002         /* es->s_uuid will be set by e2fsck if empty */
1003
1004         /*
1005          * The rest of the superblock fields should be zero, and if not it
1006          * means they are likely already in use, so leave them alone.  We
1007          * can leave it up to e2fsck to clean up any inconsistencies there.
1008          */
1009 }
1010
1011 /*
1012  * Open the external journal device
1013  */
1014 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
1015 {
1016         struct block_device *bdev;
1017
1018         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
1019         if (IS_ERR(bdev))
1020                 goto fail;
1021         return bdev;
1022
1023 fail:
1024         ext4_msg(sb, KERN_ERR,
1025                  "failed to open journal device unknown-block(%u,%u) %ld",
1026                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
1027         return NULL;
1028 }
1029
1030 /*
1031  * Release the journal device
1032  */
1033 static void ext4_blkdev_put(struct block_device *bdev)
1034 {
1035         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1036 }
1037
1038 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
1039 {
1040         struct block_device *bdev;
1041         bdev = sbi->s_journal_bdev;
1042         if (bdev) {
1043                 ext4_blkdev_put(bdev);
1044                 sbi->s_journal_bdev = NULL;
1045         }
1046 }
1047
1048 static inline struct inode *orphan_list_entry(struct list_head *l)
1049 {
1050         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1051 }
1052
1053 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1054 {
1055         struct list_head *l;
1056
1057         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1058                  le32_to_cpu(sbi->s_es->s_last_orphan));
1059
1060         printk(KERN_ERR "sb_info orphan list:\n");
1061         list_for_each(l, &sbi->s_orphan) {
1062                 struct inode *inode = orphan_list_entry(l);
1063                 printk(KERN_ERR "  "
1064                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1065                        inode->i_sb->s_id, inode->i_ino, inode,
1066                        inode->i_mode, inode->i_nlink,
1067                        NEXT_ORPHAN(inode));
1068         }
1069 }
1070
1071 #ifdef CONFIG_QUOTA
1072 static int ext4_quota_off(struct super_block *sb, int type);
1073
1074 static inline void ext4_quota_off_umount(struct super_block *sb)
1075 {
1076         int type;
1077
1078         /* Use our quota_off function to clear inode flags etc. */
1079         for (type = 0; type < EXT4_MAXQUOTAS; type++)
1080                 ext4_quota_off(sb, type);
1081 }
1082
1083 /*
1084  * This is a helper function which is used in the mount/remount
1085  * codepaths (which holds s_umount) to fetch the quota file name.
1086  */
1087 static inline char *get_qf_name(struct super_block *sb,
1088                                 struct ext4_sb_info *sbi,
1089                                 int type)
1090 {
1091         return rcu_dereference_protected(sbi->s_qf_names[type],
1092                                          lockdep_is_held(&sb->s_umount));
1093 }
1094 #else
1095 static inline void ext4_quota_off_umount(struct super_block *sb)
1096 {
1097 }
1098 #endif
1099
1100 static void ext4_put_super(struct super_block *sb)
1101 {
1102         struct ext4_sb_info *sbi = EXT4_SB(sb);
1103         struct ext4_super_block *es = sbi->s_es;
1104         struct buffer_head **group_desc;
1105         struct flex_groups **flex_groups;
1106         int aborted = 0;
1107         int i, err;
1108
1109         ext4_unregister_li_request(sb);
1110         ext4_quota_off_umount(sb);
1111
1112         destroy_workqueue(sbi->rsv_conversion_wq);
1113
1114         /*
1115          * Unregister sysfs before destroying jbd2 journal.
1116          * Since we could still access attr_journal_task attribute via sysfs
1117          * path which could have sbi->s_journal->j_task as NULL
1118          */
1119         ext4_unregister_sysfs(sb);
1120
1121         if (sbi->s_journal) {
1122                 aborted = is_journal_aborted(sbi->s_journal);
1123                 err = jbd2_journal_destroy(sbi->s_journal);
1124                 sbi->s_journal = NULL;
1125                 if ((err < 0) && !aborted) {
1126                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1127                 }
1128         }
1129
1130         ext4_es_unregister_shrinker(sbi);
1131         del_timer_sync(&sbi->s_err_report);
1132         ext4_release_system_zone(sb);
1133         ext4_mb_release(sb);
1134         ext4_ext_release(sb);
1135
1136         if (!sb_rdonly(sb) && !aborted) {
1137                 ext4_clear_feature_journal_needs_recovery(sb);
1138                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1139         }
1140         if (!sb_rdonly(sb))
1141                 ext4_commit_super(sb, 1);
1142
1143         rcu_read_lock();
1144         group_desc = rcu_dereference(sbi->s_group_desc);
1145         for (i = 0; i < sbi->s_gdb_count; i++)
1146                 brelse(group_desc[i]);
1147         kvfree(group_desc);
1148         flex_groups = rcu_dereference(sbi->s_flex_groups);
1149         if (flex_groups) {
1150                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1151                         kvfree(flex_groups[i]);
1152                 kvfree(flex_groups);
1153         }
1154         rcu_read_unlock();
1155         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1156         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1157         percpu_counter_destroy(&sbi->s_dirs_counter);
1158         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1159         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1160 #ifdef CONFIG_QUOTA
1161         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1162                 kfree(get_qf_name(sb, sbi, i));
1163 #endif
1164
1165         /* Debugging code just in case the in-memory inode orphan list
1166          * isn't empty.  The on-disk one can be non-empty if we've
1167          * detected an error and taken the fs readonly, but the
1168          * in-memory list had better be clean by this point. */
1169         if (!list_empty(&sbi->s_orphan))
1170                 dump_orphan_list(sb, sbi);
1171         J_ASSERT(list_empty(&sbi->s_orphan));
1172
1173         sync_blockdev(sb->s_bdev);
1174         invalidate_bdev(sb->s_bdev);
1175         if (sbi->s_journal_bdev && sbi->s_journal_bdev != sb->s_bdev) {
1176                 /*
1177                  * Invalidate the journal device's buffers.  We don't want them
1178                  * floating about in memory - the physical journal device may
1179                  * hotswapped, and it breaks the `ro-after' testing code.
1180                  */
1181                 sync_blockdev(sbi->s_journal_bdev);
1182                 invalidate_bdev(sbi->s_journal_bdev);
1183                 ext4_blkdev_remove(sbi);
1184         }
1185
1186         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1187         sbi->s_ea_inode_cache = NULL;
1188
1189         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1190         sbi->s_ea_block_cache = NULL;
1191
1192         if (sbi->s_mmp_tsk)
1193                 kthread_stop(sbi->s_mmp_tsk);
1194         brelse(sbi->s_sbh);
1195         sb->s_fs_info = NULL;
1196         /*
1197          * Now that we are completely done shutting down the
1198          * superblock, we need to actually destroy the kobject.
1199          */
1200         kobject_put(&sbi->s_kobj);
1201         wait_for_completion(&sbi->s_kobj_unregister);
1202         if (sbi->s_chksum_driver)
1203                 crypto_free_shash(sbi->s_chksum_driver);
1204         kfree(sbi->s_blockgroup_lock);
1205         fs_put_dax(sbi->s_daxdev);
1206         fscrypt_free_dummy_context(&sbi->s_dummy_enc_ctx);
1207 #ifdef CONFIG_UNICODE
1208         utf8_unload(sbi->s_encoding);
1209 #endif
1210         kfree(sbi);
1211 }
1212
1213 static struct kmem_cache *ext4_inode_cachep;
1214
1215 /*
1216  * Called inside transaction, so use GFP_NOFS
1217  */
1218 static struct inode *ext4_alloc_inode(struct super_block *sb)
1219 {
1220         struct ext4_inode_info *ei;
1221
1222         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1223         if (!ei)
1224                 return NULL;
1225
1226         inode_set_iversion(&ei->vfs_inode, 1);
1227         spin_lock_init(&ei->i_raw_lock);
1228         INIT_LIST_HEAD(&ei->i_prealloc_list);
1229         atomic_set(&ei->i_prealloc_active, 0);
1230         spin_lock_init(&ei->i_prealloc_lock);
1231         ext4_es_init_tree(&ei->i_es_tree);
1232         rwlock_init(&ei->i_es_lock);
1233         INIT_LIST_HEAD(&ei->i_es_list);
1234         ei->i_es_all_nr = 0;
1235         ei->i_es_shk_nr = 0;
1236         ei->i_es_shrink_lblk = 0;
1237         ei->i_reserved_data_blocks = 0;
1238         spin_lock_init(&(ei->i_block_reservation_lock));
1239         ext4_init_pending_tree(&ei->i_pending_tree);
1240 #ifdef CONFIG_QUOTA
1241         ei->i_reserved_quota = 0;
1242         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1243 #endif
1244         ei->jinode = NULL;
1245         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1246         spin_lock_init(&ei->i_completed_io_lock);
1247         ei->i_sync_tid = 0;
1248         ei->i_datasync_tid = 0;
1249         atomic_set(&ei->i_unwritten, 0);
1250         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1251         return &ei->vfs_inode;
1252 }
1253
1254 static int ext4_drop_inode(struct inode *inode)
1255 {
1256         int drop = generic_drop_inode(inode);
1257
1258         if (!drop)
1259                 drop = fscrypt_drop_inode(inode);
1260
1261         trace_ext4_drop_inode(inode, drop);
1262         return drop;
1263 }
1264
1265 static void ext4_free_in_core_inode(struct inode *inode)
1266 {
1267         fscrypt_free_inode(inode);
1268         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1269 }
1270
1271 static void ext4_destroy_inode(struct inode *inode)
1272 {
1273         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1274                 ext4_msg(inode->i_sb, KERN_ERR,
1275                          "Inode %lu (%p): orphan list check failed!",
1276                          inode->i_ino, EXT4_I(inode));
1277                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1278                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1279                                 true);
1280                 dump_stack();
1281         }
1282 }
1283
1284 static void init_once(void *foo)
1285 {
1286         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1287
1288         INIT_LIST_HEAD(&ei->i_orphan);
1289         init_rwsem(&ei->xattr_sem);
1290         init_rwsem(&ei->i_data_sem);
1291         init_rwsem(&ei->i_mmap_sem);
1292         inode_init_once(&ei->vfs_inode);
1293 }
1294
1295 static int __init init_inodecache(void)
1296 {
1297         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1298                                 sizeof(struct ext4_inode_info), 0,
1299                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1300                                         SLAB_ACCOUNT),
1301                                 offsetof(struct ext4_inode_info, i_data),
1302                                 sizeof_field(struct ext4_inode_info, i_data),
1303                                 init_once);
1304         if (ext4_inode_cachep == NULL)
1305                 return -ENOMEM;
1306         return 0;
1307 }
1308
1309 static void destroy_inodecache(void)
1310 {
1311         /*
1312          * Make sure all delayed rcu free inodes are flushed before we
1313          * destroy cache.
1314          */
1315         rcu_barrier();
1316         kmem_cache_destroy(ext4_inode_cachep);
1317 }
1318
1319 void ext4_clear_inode(struct inode *inode)
1320 {
1321         invalidate_inode_buffers(inode);
1322         clear_inode(inode);
1323         ext4_discard_preallocations(inode, 0);
1324         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1325         dquot_drop(inode);
1326         if (EXT4_I(inode)->jinode) {
1327                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1328                                                EXT4_I(inode)->jinode);
1329                 jbd2_free_inode(EXT4_I(inode)->jinode);
1330                 EXT4_I(inode)->jinode = NULL;
1331         }
1332         fscrypt_put_encryption_info(inode);
1333         fsverity_cleanup_inode(inode);
1334 }
1335
1336 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1337                                         u64 ino, u32 generation)
1338 {
1339         struct inode *inode;
1340
1341         /*
1342          * Currently we don't know the generation for parent directory, so
1343          * a generation of 0 means "accept any"
1344          */
1345         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1346         if (IS_ERR(inode))
1347                 return ERR_CAST(inode);
1348         if (generation && inode->i_generation != generation) {
1349                 iput(inode);
1350                 return ERR_PTR(-ESTALE);
1351         }
1352
1353         return inode;
1354 }
1355
1356 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1357                                         int fh_len, int fh_type)
1358 {
1359         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1360                                     ext4_nfs_get_inode);
1361 }
1362
1363 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1364                                         int fh_len, int fh_type)
1365 {
1366         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1367                                     ext4_nfs_get_inode);
1368 }
1369
1370 static int ext4_nfs_commit_metadata(struct inode *inode)
1371 {
1372         struct writeback_control wbc = {
1373                 .sync_mode = WB_SYNC_ALL
1374         };
1375
1376         trace_ext4_nfs_commit_metadata(inode);
1377         return ext4_write_inode(inode, &wbc);
1378 }
1379
1380 /*
1381  * Try to release metadata pages (indirect blocks, directories) which are
1382  * mapped via the block device.  Since these pages could have journal heads
1383  * which would prevent try_to_free_buffers() from freeing them, we must use
1384  * jbd2 layer's try_to_free_buffers() function to release them.
1385  */
1386 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1387                                  gfp_t wait)
1388 {
1389         journal_t *journal = EXT4_SB(sb)->s_journal;
1390
1391         WARN_ON(PageChecked(page));
1392         if (!page_has_buffers(page))
1393                 return 0;
1394         if (journal)
1395                 return jbd2_journal_try_to_free_buffers(journal, page);
1396
1397         return try_to_free_buffers(page);
1398 }
1399
1400 #ifdef CONFIG_FS_ENCRYPTION
1401 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1402 {
1403         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1404                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1405 }
1406
1407 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1408                                                         void *fs_data)
1409 {
1410         handle_t *handle = fs_data;
1411         int res, res2, credits, retries = 0;
1412
1413         /*
1414          * Encrypting the root directory is not allowed because e2fsck expects
1415          * lost+found to exist and be unencrypted, and encrypting the root
1416          * directory would imply encrypting the lost+found directory as well as
1417          * the filename "lost+found" itself.
1418          */
1419         if (inode->i_ino == EXT4_ROOT_INO)
1420                 return -EPERM;
1421
1422         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1423                 return -EINVAL;
1424
1425         if (ext4_test_inode_flag(inode, EXT4_INODE_DAX))
1426                 return -EOPNOTSUPP;
1427
1428         res = ext4_convert_inline_data(inode);
1429         if (res)
1430                 return res;
1431
1432         /*
1433          * If a journal handle was specified, then the encryption context is
1434          * being set on a new inode via inheritance and is part of a larger
1435          * transaction to create the inode.  Otherwise the encryption context is
1436          * being set on an existing inode in its own transaction.  Only in the
1437          * latter case should the "retry on ENOSPC" logic be used.
1438          */
1439
1440         if (handle) {
1441                 res = ext4_xattr_set_handle(handle, inode,
1442                                             EXT4_XATTR_INDEX_ENCRYPTION,
1443                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1444                                             ctx, len, 0);
1445                 if (!res) {
1446                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1447                         ext4_clear_inode_state(inode,
1448                                         EXT4_STATE_MAY_INLINE_DATA);
1449                         /*
1450                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1451                          * S_DAX may be disabled
1452                          */
1453                         ext4_set_inode_flags(inode, false);
1454                 }
1455                 return res;
1456         }
1457
1458         res = dquot_initialize(inode);
1459         if (res)
1460                 return res;
1461 retry:
1462         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1463                                      &credits);
1464         if (res)
1465                 return res;
1466
1467         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1468         if (IS_ERR(handle))
1469                 return PTR_ERR(handle);
1470
1471         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1472                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1473                                     ctx, len, 0);
1474         if (!res) {
1475                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1476                 /*
1477                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1478                  * S_DAX may be disabled
1479                  */
1480                 ext4_set_inode_flags(inode, false);
1481                 res = ext4_mark_inode_dirty(handle, inode);
1482                 if (res)
1483                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1484         }
1485         res2 = ext4_journal_stop(handle);
1486
1487         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1488                 goto retry;
1489         if (!res)
1490                 res = res2;
1491         return res;
1492 }
1493
1494 static const union fscrypt_context *
1495 ext4_get_dummy_context(struct super_block *sb)
1496 {
1497         return EXT4_SB(sb)->s_dummy_enc_ctx.ctx;
1498 }
1499
1500 static bool ext4_has_stable_inodes(struct super_block *sb)
1501 {
1502         return ext4_has_feature_stable_inodes(sb);
1503 }
1504
1505 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1506                                        int *ino_bits_ret, int *lblk_bits_ret)
1507 {
1508         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1509         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1510 }
1511
1512 static const struct fscrypt_operations ext4_cryptops = {
1513         .key_prefix             = "ext4:",
1514         .get_context            = ext4_get_context,
1515         .set_context            = ext4_set_context,
1516         .get_dummy_context      = ext4_get_dummy_context,
1517         .empty_dir              = ext4_empty_dir,
1518         .max_namelen            = EXT4_NAME_LEN,
1519         .has_stable_inodes      = ext4_has_stable_inodes,
1520         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1521 };
1522 #endif
1523
1524 #ifdef CONFIG_QUOTA
1525 static const char * const quotatypes[] = INITQFNAMES;
1526 #define QTYPE2NAME(t) (quotatypes[t])
1527
1528 static int ext4_write_dquot(struct dquot *dquot);
1529 static int ext4_acquire_dquot(struct dquot *dquot);
1530 static int ext4_release_dquot(struct dquot *dquot);
1531 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1532 static int ext4_write_info(struct super_block *sb, int type);
1533 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1534                          const struct path *path);
1535 static int ext4_quota_on_mount(struct super_block *sb, int type);
1536 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1537                                size_t len, loff_t off);
1538 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1539                                 const char *data, size_t len, loff_t off);
1540 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1541                              unsigned int flags);
1542 static int ext4_enable_quotas(struct super_block *sb);
1543
1544 static struct dquot **ext4_get_dquots(struct inode *inode)
1545 {
1546         return EXT4_I(inode)->i_dquot;
1547 }
1548
1549 static const struct dquot_operations ext4_quota_operations = {
1550         .get_reserved_space     = ext4_get_reserved_space,
1551         .write_dquot            = ext4_write_dquot,
1552         .acquire_dquot          = ext4_acquire_dquot,
1553         .release_dquot          = ext4_release_dquot,
1554         .mark_dirty             = ext4_mark_dquot_dirty,
1555         .write_info             = ext4_write_info,
1556         .alloc_dquot            = dquot_alloc,
1557         .destroy_dquot          = dquot_destroy,
1558         .get_projid             = ext4_get_projid,
1559         .get_inode_usage        = ext4_get_inode_usage,
1560         .get_next_id            = dquot_get_next_id,
1561 };
1562
1563 static const struct quotactl_ops ext4_qctl_operations = {
1564         .quota_on       = ext4_quota_on,
1565         .quota_off      = ext4_quota_off,
1566         .quota_sync     = dquot_quota_sync,
1567         .get_state      = dquot_get_state,
1568         .set_info       = dquot_set_dqinfo,
1569         .get_dqblk      = dquot_get_dqblk,
1570         .set_dqblk      = dquot_set_dqblk,
1571         .get_nextdqblk  = dquot_get_next_dqblk,
1572 };
1573 #endif
1574
1575 static const struct super_operations ext4_sops = {
1576         .alloc_inode    = ext4_alloc_inode,
1577         .free_inode     = ext4_free_in_core_inode,
1578         .destroy_inode  = ext4_destroy_inode,
1579         .write_inode    = ext4_write_inode,
1580         .dirty_inode    = ext4_dirty_inode,
1581         .drop_inode     = ext4_drop_inode,
1582         .evict_inode    = ext4_evict_inode,
1583         .put_super      = ext4_put_super,
1584         .sync_fs        = ext4_sync_fs,
1585         .freeze_fs      = ext4_freeze,
1586         .unfreeze_fs    = ext4_unfreeze,
1587         .statfs         = ext4_statfs,
1588         .remount_fs     = ext4_remount,
1589         .show_options   = ext4_show_options,
1590 #ifdef CONFIG_QUOTA
1591         .quota_read     = ext4_quota_read,
1592         .quota_write    = ext4_quota_write,
1593         .get_dquots     = ext4_get_dquots,
1594 #endif
1595         .bdev_try_to_free_page = bdev_try_to_free_page,
1596 };
1597
1598 static const struct export_operations ext4_export_ops = {
1599         .fh_to_dentry = ext4_fh_to_dentry,
1600         .fh_to_parent = ext4_fh_to_parent,
1601         .get_parent = ext4_get_parent,
1602         .commit_metadata = ext4_nfs_commit_metadata,
1603 };
1604
1605 enum {
1606         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1607         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1608         Opt_nouid32, Opt_debug, Opt_removed,
1609         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1610         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1611         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1612         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1613         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1614         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1615         Opt_inlinecrypt,
1616         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1617         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1618         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1619         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
1620         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1621         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1622         Opt_nowarn_on_error, Opt_mblk_io_submit,
1623         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1624         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1625         Opt_inode_readahead_blks, Opt_journal_ioprio,
1626         Opt_dioread_nolock, Opt_dioread_lock,
1627         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1628         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1629         Opt_prefetch_block_bitmaps,
1630 };
1631
1632 static const match_table_t tokens = {
1633         {Opt_bsd_df, "bsddf"},
1634         {Opt_minix_df, "minixdf"},
1635         {Opt_grpid, "grpid"},
1636         {Opt_grpid, "bsdgroups"},
1637         {Opt_nogrpid, "nogrpid"},
1638         {Opt_nogrpid, "sysvgroups"},
1639         {Opt_resgid, "resgid=%u"},
1640         {Opt_resuid, "resuid=%u"},
1641         {Opt_sb, "sb=%u"},
1642         {Opt_err_cont, "errors=continue"},
1643         {Opt_err_panic, "errors=panic"},
1644         {Opt_err_ro, "errors=remount-ro"},
1645         {Opt_nouid32, "nouid32"},
1646         {Opt_debug, "debug"},
1647         {Opt_removed, "oldalloc"},
1648         {Opt_removed, "orlov"},
1649         {Opt_user_xattr, "user_xattr"},
1650         {Opt_nouser_xattr, "nouser_xattr"},
1651         {Opt_acl, "acl"},
1652         {Opt_noacl, "noacl"},
1653         {Opt_noload, "norecovery"},
1654         {Opt_noload, "noload"},
1655         {Opt_removed, "nobh"},
1656         {Opt_removed, "bh"},
1657         {Opt_commit, "commit=%u"},
1658         {Opt_min_batch_time, "min_batch_time=%u"},
1659         {Opt_max_batch_time, "max_batch_time=%u"},
1660         {Opt_journal_dev, "journal_dev=%u"},
1661         {Opt_journal_path, "journal_path=%s"},
1662         {Opt_journal_checksum, "journal_checksum"},
1663         {Opt_nojournal_checksum, "nojournal_checksum"},
1664         {Opt_journal_async_commit, "journal_async_commit"},
1665         {Opt_abort, "abort"},
1666         {Opt_data_journal, "data=journal"},
1667         {Opt_data_ordered, "data=ordered"},
1668         {Opt_data_writeback, "data=writeback"},
1669         {Opt_data_err_abort, "data_err=abort"},
1670         {Opt_data_err_ignore, "data_err=ignore"},
1671         {Opt_offusrjquota, "usrjquota="},
1672         {Opt_usrjquota, "usrjquota=%s"},
1673         {Opt_offgrpjquota, "grpjquota="},
1674         {Opt_grpjquota, "grpjquota=%s"},
1675         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1676         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1677         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1678         {Opt_grpquota, "grpquota"},
1679         {Opt_noquota, "noquota"},
1680         {Opt_quota, "quota"},
1681         {Opt_usrquota, "usrquota"},
1682         {Opt_prjquota, "prjquota"},
1683         {Opt_barrier, "barrier=%u"},
1684         {Opt_barrier, "barrier"},
1685         {Opt_nobarrier, "nobarrier"},
1686         {Opt_i_version, "i_version"},
1687         {Opt_dax, "dax"},
1688         {Opt_dax_always, "dax=always"},
1689         {Opt_dax_inode, "dax=inode"},
1690         {Opt_dax_never, "dax=never"},
1691         {Opt_stripe, "stripe=%u"},
1692         {Opt_delalloc, "delalloc"},
1693         {Opt_warn_on_error, "warn_on_error"},
1694         {Opt_nowarn_on_error, "nowarn_on_error"},
1695         {Opt_lazytime, "lazytime"},
1696         {Opt_nolazytime, "nolazytime"},
1697         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1698         {Opt_nodelalloc, "nodelalloc"},
1699         {Opt_removed, "mblk_io_submit"},
1700         {Opt_removed, "nomblk_io_submit"},
1701         {Opt_block_validity, "block_validity"},
1702         {Opt_noblock_validity, "noblock_validity"},
1703         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1704         {Opt_journal_ioprio, "journal_ioprio=%u"},
1705         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1706         {Opt_auto_da_alloc, "auto_da_alloc"},
1707         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1708         {Opt_dioread_nolock, "dioread_nolock"},
1709         {Opt_dioread_lock, "nodioread_nolock"},
1710         {Opt_dioread_lock, "dioread_lock"},
1711         {Opt_discard, "discard"},
1712         {Opt_nodiscard, "nodiscard"},
1713         {Opt_init_itable, "init_itable=%u"},
1714         {Opt_init_itable, "init_itable"},
1715         {Opt_noinit_itable, "noinit_itable"},
1716         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1717         {Opt_test_dummy_encryption, "test_dummy_encryption=%s"},
1718         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1719         {Opt_inlinecrypt, "inlinecrypt"},
1720         {Opt_nombcache, "nombcache"},
1721         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1722         {Opt_prefetch_block_bitmaps, "prefetch_block_bitmaps"},
1723         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1724         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1725         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1726         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1727         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1728         {Opt_err, NULL},
1729 };
1730
1731 static ext4_fsblk_t get_sb_block(void **data)
1732 {
1733         ext4_fsblk_t    sb_block;
1734         char            *options = (char *) *data;
1735
1736         if (!options || strncmp(options, "sb=", 3) != 0)
1737                 return 1;       /* Default location */
1738
1739         options += 3;
1740         /* TODO: use simple_strtoll with >32bit ext4 */
1741         sb_block = simple_strtoul(options, &options, 0);
1742         if (*options && *options != ',') {
1743                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1744                        (char *) *data);
1745                 return 1;
1746         }
1747         if (*options == ',')
1748                 options++;
1749         *data = (void *) options;
1750
1751         return sb_block;
1752 }
1753
1754 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1755 static const char deprecated_msg[] =
1756         "Mount option \"%s\" will be removed by %s\n"
1757         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1758
1759 #ifdef CONFIG_QUOTA
1760 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1761 {
1762         struct ext4_sb_info *sbi = EXT4_SB(sb);
1763         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1764         int ret = -1;
1765
1766         if (sb_any_quota_loaded(sb) && !old_qname) {
1767                 ext4_msg(sb, KERN_ERR,
1768                         "Cannot change journaled "
1769                         "quota options when quota turned on");
1770                 return -1;
1771         }
1772         if (ext4_has_feature_quota(sb)) {
1773                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1774                          "ignored when QUOTA feature is enabled");
1775                 return 1;
1776         }
1777         qname = match_strdup(args);
1778         if (!qname) {
1779                 ext4_msg(sb, KERN_ERR,
1780                         "Not enough memory for storing quotafile name");
1781                 return -1;
1782         }
1783         if (old_qname) {
1784                 if (strcmp(old_qname, qname) == 0)
1785                         ret = 1;
1786                 else
1787                         ext4_msg(sb, KERN_ERR,
1788                                  "%s quota file already specified",
1789                                  QTYPE2NAME(qtype));
1790                 goto errout;
1791         }
1792         if (strchr(qname, '/')) {
1793                 ext4_msg(sb, KERN_ERR,
1794                         "quotafile must be on filesystem root");
1795                 goto errout;
1796         }
1797         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1798         set_opt(sb, QUOTA);
1799         return 1;
1800 errout:
1801         kfree(qname);
1802         return ret;
1803 }
1804
1805 static int clear_qf_name(struct super_block *sb, int qtype)
1806 {
1807
1808         struct ext4_sb_info *sbi = EXT4_SB(sb);
1809         char *old_qname = get_qf_name(sb, sbi, qtype);
1810
1811         if (sb_any_quota_loaded(sb) && old_qname) {
1812                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1813                         " when quota turned on");
1814                 return -1;
1815         }
1816         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1817         synchronize_rcu();
1818         kfree(old_qname);
1819         return 1;
1820 }
1821 #endif
1822
1823 #define MOPT_SET        0x0001
1824 #define MOPT_CLEAR      0x0002
1825 #define MOPT_NOSUPPORT  0x0004
1826 #define MOPT_EXPLICIT   0x0008
1827 #define MOPT_CLEAR_ERR  0x0010
1828 #define MOPT_GTE0       0x0020
1829 #ifdef CONFIG_QUOTA
1830 #define MOPT_Q          0
1831 #define MOPT_QFMT       0x0040
1832 #else
1833 #define MOPT_Q          MOPT_NOSUPPORT
1834 #define MOPT_QFMT       MOPT_NOSUPPORT
1835 #endif
1836 #define MOPT_DATAJ      0x0080
1837 #define MOPT_NO_EXT2    0x0100
1838 #define MOPT_NO_EXT3    0x0200
1839 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1840 #define MOPT_STRING     0x0400
1841 #define MOPT_SKIP       0x0800
1842
1843 static const struct mount_opts {
1844         int     token;
1845         int     mount_opt;
1846         int     flags;
1847 } ext4_mount_opts[] = {
1848         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1849         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1850         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1851         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1852         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1853         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1854         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1855          MOPT_EXT4_ONLY | MOPT_SET},
1856         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1857          MOPT_EXT4_ONLY | MOPT_CLEAR},
1858         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1859         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1860         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1861          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1862         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1863          MOPT_EXT4_ONLY | MOPT_CLEAR},
1864         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1865         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1866         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1867          MOPT_EXT4_ONLY | MOPT_CLEAR},
1868         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1869          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1870         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1871                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1872          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1873         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1874         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1875         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1876         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1877         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1878          MOPT_NO_EXT2},
1879         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1880          MOPT_NO_EXT2},
1881         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1882         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1883         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1884         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1885         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1886         {Opt_commit, 0, MOPT_GTE0},
1887         {Opt_max_batch_time, 0, MOPT_GTE0},
1888         {Opt_min_batch_time, 0, MOPT_GTE0},
1889         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1890         {Opt_init_itable, 0, MOPT_GTE0},
1891         {Opt_dax, EXT4_MOUNT_DAX_ALWAYS, MOPT_SET | MOPT_SKIP},
1892         {Opt_dax_always, EXT4_MOUNT_DAX_ALWAYS,
1893                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1894         {Opt_dax_inode, EXT4_MOUNT2_DAX_INODE,
1895                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1896         {Opt_dax_never, EXT4_MOUNT2_DAX_NEVER,
1897                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1898         {Opt_stripe, 0, MOPT_GTE0},
1899         {Opt_resuid, 0, MOPT_GTE0},
1900         {Opt_resgid, 0, MOPT_GTE0},
1901         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1902         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1903         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1904         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1905         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1906         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1907          MOPT_NO_EXT2 | MOPT_DATAJ},
1908         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1909         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1910 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1911         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1912         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1913 #else
1914         {Opt_acl, 0, MOPT_NOSUPPORT},
1915         {Opt_noacl, 0, MOPT_NOSUPPORT},
1916 #endif
1917         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1918         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1919         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1920         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1921         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1922                                                         MOPT_SET | MOPT_Q},
1923         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1924                                                         MOPT_SET | MOPT_Q},
1925         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1926                                                         MOPT_SET | MOPT_Q},
1927         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1928                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1929                                                         MOPT_CLEAR | MOPT_Q},
1930         {Opt_usrjquota, 0, MOPT_Q},
1931         {Opt_grpjquota, 0, MOPT_Q},
1932         {Opt_offusrjquota, 0, MOPT_Q},
1933         {Opt_offgrpjquota, 0, MOPT_Q},
1934         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1935         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1936         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1937         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1938         {Opt_test_dummy_encryption, 0, MOPT_STRING},
1939         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1940         {Opt_prefetch_block_bitmaps, EXT4_MOUNT_PREFETCH_BLOCK_BITMAPS,
1941          MOPT_SET},
1942         {Opt_err, 0, 0}
1943 };
1944
1945 #ifdef CONFIG_UNICODE
1946 static const struct ext4_sb_encodings {
1947         __u16 magic;
1948         char *name;
1949         char *version;
1950 } ext4_sb_encoding_map[] = {
1951         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
1952 };
1953
1954 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
1955                                  const struct ext4_sb_encodings **encoding,
1956                                  __u16 *flags)
1957 {
1958         __u16 magic = le16_to_cpu(es->s_encoding);
1959         int i;
1960
1961         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1962                 if (magic == ext4_sb_encoding_map[i].magic)
1963                         break;
1964
1965         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
1966                 return -EINVAL;
1967
1968         *encoding = &ext4_sb_encoding_map[i];
1969         *flags = le16_to_cpu(es->s_encoding_flags);
1970
1971         return 0;
1972 }
1973 #endif
1974
1975 static int ext4_set_test_dummy_encryption(struct super_block *sb,
1976                                           const char *opt,
1977                                           const substring_t *arg,
1978                                           bool is_remount)
1979 {
1980 #ifdef CONFIG_FS_ENCRYPTION
1981         struct ext4_sb_info *sbi = EXT4_SB(sb);
1982         int err;
1983
1984         /*
1985          * This mount option is just for testing, and it's not worthwhile to
1986          * implement the extra complexity (e.g. RCU protection) that would be
1987          * needed to allow it to be set or changed during remount.  We do allow
1988          * it to be specified during remount, but only if there is no change.
1989          */
1990         if (is_remount && !sbi->s_dummy_enc_ctx.ctx) {
1991                 ext4_msg(sb, KERN_WARNING,
1992                          "Can't set test_dummy_encryption on remount");
1993                 return -1;
1994         }
1995         err = fscrypt_set_test_dummy_encryption(sb, arg, &sbi->s_dummy_enc_ctx);
1996         if (err) {
1997                 if (err == -EEXIST)
1998                         ext4_msg(sb, KERN_WARNING,
1999                                  "Can't change test_dummy_encryption on remount");
2000                 else if (err == -EINVAL)
2001                         ext4_msg(sb, KERN_WARNING,
2002                                  "Value of option \"%s\" is unrecognized", opt);
2003                 else
2004                         ext4_msg(sb, KERN_WARNING,
2005                                  "Error processing option \"%s\" [%d]",
2006                                  opt, err);
2007                 return -1;
2008         }
2009         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2010 #else
2011         ext4_msg(sb, KERN_WARNING,
2012                  "Test dummy encryption mount option ignored");
2013 #endif
2014         return 1;
2015 }
2016
2017 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
2018                             substring_t *args, unsigned long *journal_devnum,
2019                             unsigned int *journal_ioprio, int is_remount)
2020 {
2021         struct ext4_sb_info *sbi = EXT4_SB(sb);
2022         const struct mount_opts *m;
2023         kuid_t uid;
2024         kgid_t gid;
2025         int arg = 0;
2026
2027 #ifdef CONFIG_QUOTA
2028         if (token == Opt_usrjquota)
2029                 return set_qf_name(sb, USRQUOTA, &args[0]);
2030         else if (token == Opt_grpjquota)
2031                 return set_qf_name(sb, GRPQUOTA, &args[0]);
2032         else if (token == Opt_offusrjquota)
2033                 return clear_qf_name(sb, USRQUOTA);
2034         else if (token == Opt_offgrpjquota)
2035                 return clear_qf_name(sb, GRPQUOTA);
2036 #endif
2037         switch (token) {
2038         case Opt_noacl:
2039         case Opt_nouser_xattr:
2040                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
2041                 break;
2042         case Opt_sb:
2043                 return 1;       /* handled by get_sb_block() */
2044         case Opt_removed:
2045                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
2046                 return 1;
2047         case Opt_abort:
2048                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
2049                 return 1;
2050         case Opt_i_version:
2051                 sb->s_flags |= SB_I_VERSION;
2052                 return 1;
2053         case Opt_lazytime:
2054                 sb->s_flags |= SB_LAZYTIME;
2055                 return 1;
2056         case Opt_nolazytime:
2057                 sb->s_flags &= ~SB_LAZYTIME;
2058                 return 1;
2059         case Opt_inlinecrypt:
2060 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2061                 sb->s_flags |= SB_INLINECRYPT;
2062 #else
2063                 ext4_msg(sb, KERN_ERR, "inline encryption not supported");
2064 #endif
2065                 return 1;
2066         }
2067
2068         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2069                 if (token == m->token)
2070                         break;
2071
2072         if (m->token == Opt_err) {
2073                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
2074                          "or missing value", opt);
2075                 return -1;
2076         }
2077
2078         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2079                 ext4_msg(sb, KERN_ERR,
2080                          "Mount option \"%s\" incompatible with ext2", opt);
2081                 return -1;
2082         }
2083         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2084                 ext4_msg(sb, KERN_ERR,
2085                          "Mount option \"%s\" incompatible with ext3", opt);
2086                 return -1;
2087         }
2088
2089         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
2090                 return -1;
2091         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
2092                 return -1;
2093         if (m->flags & MOPT_EXPLICIT) {
2094                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2095                         set_opt2(sb, EXPLICIT_DELALLOC);
2096                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2097                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
2098                 } else
2099                         return -1;
2100         }
2101         if (m->flags & MOPT_CLEAR_ERR)
2102                 clear_opt(sb, ERRORS_MASK);
2103         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
2104                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
2105                          "options when quota turned on");
2106                 return -1;
2107         }
2108
2109         if (m->flags & MOPT_NOSUPPORT) {
2110                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
2111         } else if (token == Opt_commit) {
2112                 if (arg == 0)
2113                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
2114                 else if (arg > INT_MAX / HZ) {
2115                         ext4_msg(sb, KERN_ERR,
2116                                  "Invalid commit interval %d, "
2117                                  "must be smaller than %d",
2118                                  arg, INT_MAX / HZ);
2119                         return -1;
2120                 }
2121                 sbi->s_commit_interval = HZ * arg;
2122         } else if (token == Opt_debug_want_extra_isize) {
2123                 if ((arg & 1) ||
2124                     (arg < 4) ||
2125                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
2126                         ext4_msg(sb, KERN_ERR,
2127                                  "Invalid want_extra_isize %d", arg);
2128                         return -1;
2129                 }
2130                 sbi->s_want_extra_isize = arg;
2131         } else if (token == Opt_max_batch_time) {
2132                 sbi->s_max_batch_time = arg;
2133         } else if (token == Opt_min_batch_time) {
2134                 sbi->s_min_batch_time = arg;
2135         } else if (token == Opt_inode_readahead_blks) {
2136                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
2137                         ext4_msg(sb, KERN_ERR,
2138                                  "EXT4-fs: inode_readahead_blks must be "
2139                                  "0 or a power of 2 smaller than 2^31");
2140                         return -1;
2141                 }
2142                 sbi->s_inode_readahead_blks = arg;
2143         } else if (token == Opt_init_itable) {
2144                 set_opt(sb, INIT_INODE_TABLE);
2145                 if (!args->from)
2146                         arg = EXT4_DEF_LI_WAIT_MULT;
2147                 sbi->s_li_wait_mult = arg;
2148         } else if (token == Opt_max_dir_size_kb) {
2149                 sbi->s_max_dir_size_kb = arg;
2150         } else if (token == Opt_stripe) {
2151                 sbi->s_stripe = arg;
2152         } else if (token == Opt_resuid) {
2153                 uid = make_kuid(current_user_ns(), arg);
2154                 if (!uid_valid(uid)) {
2155                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
2156                         return -1;
2157                 }
2158                 sbi->s_resuid = uid;
2159         } else if (token == Opt_resgid) {
2160                 gid = make_kgid(current_user_ns(), arg);
2161                 if (!gid_valid(gid)) {
2162                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
2163                         return -1;
2164                 }
2165                 sbi->s_resgid = gid;
2166         } else if (token == Opt_journal_dev) {
2167                 if (is_remount) {
2168                         ext4_msg(sb, KERN_ERR,
2169                                  "Cannot specify journal on remount");
2170                         return -1;
2171                 }
2172                 *journal_devnum = arg;
2173         } else if (token == Opt_journal_path) {
2174                 char *journal_path;
2175                 struct inode *journal_inode;
2176                 struct path path;
2177                 int error;
2178
2179                 if (is_remount) {
2180                         ext4_msg(sb, KERN_ERR,
2181                                  "Cannot specify journal on remount");
2182                         return -1;
2183                 }
2184                 journal_path = match_strdup(&args[0]);
2185                 if (!journal_path) {
2186                         ext4_msg(sb, KERN_ERR, "error: could not dup "
2187                                 "journal device string");
2188                         return -1;
2189                 }
2190
2191                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2192                 if (error) {
2193                         ext4_msg(sb, KERN_ERR, "error: could not find "
2194                                 "journal device path: error %d", error);
2195                         kfree(journal_path);
2196                         return -1;
2197                 }
2198
2199                 journal_inode = d_inode(path.dentry);
2200                 if (!S_ISBLK(journal_inode->i_mode)) {
2201                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
2202                                 "is not a block device", journal_path);
2203                         path_put(&path);
2204                         kfree(journal_path);
2205                         return -1;
2206                 }
2207
2208                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
2209                 path_put(&path);
2210                 kfree(journal_path);
2211         } else if (token == Opt_journal_ioprio) {
2212                 if (arg > 7) {
2213                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2214                                  " (must be 0-7)");
2215                         return -1;
2216                 }
2217                 *journal_ioprio =
2218                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2219         } else if (token == Opt_test_dummy_encryption) {
2220                 return ext4_set_test_dummy_encryption(sb, opt, &args[0],
2221                                                       is_remount);
2222         } else if (m->flags & MOPT_DATAJ) {
2223                 if (is_remount) {
2224                         if (!sbi->s_journal)
2225                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2226                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2227                                 ext4_msg(sb, KERN_ERR,
2228                                          "Cannot change data mode on remount");
2229                                 return -1;
2230                         }
2231                 } else {
2232                         clear_opt(sb, DATA_FLAGS);
2233                         sbi->s_mount_opt |= m->mount_opt;
2234                 }
2235 #ifdef CONFIG_QUOTA
2236         } else if (m->flags & MOPT_QFMT) {
2237                 if (sb_any_quota_loaded(sb) &&
2238                     sbi->s_jquota_fmt != m->mount_opt) {
2239                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2240                                  "quota options when quota turned on");
2241                         return -1;
2242                 }
2243                 if (ext4_has_feature_quota(sb)) {
2244                         ext4_msg(sb, KERN_INFO,
2245                                  "Quota format mount options ignored "
2246                                  "when QUOTA feature is enabled");
2247                         return 1;
2248                 }
2249                 sbi->s_jquota_fmt = m->mount_opt;
2250 #endif
2251         } else if (token == Opt_dax || token == Opt_dax_always ||
2252                    token == Opt_dax_inode || token == Opt_dax_never) {
2253 #ifdef CONFIG_FS_DAX
2254                 switch (token) {
2255                 case Opt_dax:
2256                 case Opt_dax_always:
2257                         if (is_remount &&
2258                             (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2259                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2260                         fail_dax_change_remount:
2261                                 ext4_msg(sb, KERN_ERR, "can't change "
2262                                          "dax mount option while remounting");
2263                                 return -1;
2264                         }
2265                         if (is_remount &&
2266                             (test_opt(sb, DATA_FLAGS) ==
2267                              EXT4_MOUNT_JOURNAL_DATA)) {
2268                                     ext4_msg(sb, KERN_ERR, "can't mount with "
2269                                              "both data=journal and dax");
2270                                     return -1;
2271                         }
2272                         ext4_msg(sb, KERN_WARNING,
2273                                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2274                         sbi->s_mount_opt |= EXT4_MOUNT_DAX_ALWAYS;
2275                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2276                         break;
2277                 case Opt_dax_never:
2278                         if (is_remount &&
2279                             (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2280                              (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS)))
2281                                 goto fail_dax_change_remount;
2282                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2283                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2284                         break;
2285                 case Opt_dax_inode:
2286                         if (is_remount &&
2287                             ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2288                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2289                              !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE)))
2290                                 goto fail_dax_change_remount;
2291                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2292                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2293                         /* Strictly for printing options */
2294                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_INODE;
2295                         break;
2296                 }
2297 #else
2298                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2299                 sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2300                 sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2301                 return -1;
2302 #endif
2303         } else if (token == Opt_data_err_abort) {
2304                 sbi->s_mount_opt |= m->mount_opt;
2305         } else if (token == Opt_data_err_ignore) {
2306                 sbi->s_mount_opt &= ~m->mount_opt;
2307         } else {
2308                 if (!args->from)
2309                         arg = 1;
2310                 if (m->flags & MOPT_CLEAR)
2311                         arg = !arg;
2312                 else if (unlikely(!(m->flags & MOPT_SET))) {
2313                         ext4_msg(sb, KERN_WARNING,
2314                                  "buggy handling of option %s", opt);
2315                         WARN_ON(1);
2316                         return -1;
2317                 }
2318                 if (arg != 0)
2319                         sbi->s_mount_opt |= m->mount_opt;
2320                 else
2321                         sbi->s_mount_opt &= ~m->mount_opt;
2322         }
2323         return 1;
2324 }
2325
2326 static int parse_options(char *options, struct super_block *sb,
2327                          unsigned long *journal_devnum,
2328                          unsigned int *journal_ioprio,
2329                          int is_remount)
2330 {
2331         struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2332         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2333         substring_t args[MAX_OPT_ARGS];
2334         int token;
2335
2336         if (!options)
2337                 return 1;
2338
2339         while ((p = strsep(&options, ",")) != NULL) {
2340                 if (!*p)
2341                         continue;
2342                 /*
2343                  * Initialize args struct so we know whether arg was
2344                  * found; some options take optional arguments.
2345                  */
2346                 args[0].to = args[0].from = NULL;
2347                 token = match_token(p, tokens, args);
2348                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2349                                      journal_ioprio, is_remount) < 0)
2350                         return 0;
2351         }
2352 #ifdef CONFIG_QUOTA
2353         /*
2354          * We do the test below only for project quotas. 'usrquota' and
2355          * 'grpquota' mount options are allowed even without quota feature
2356          * to support legacy quotas in quota files.
2357          */
2358         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2359                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2360                          "Cannot enable project quota enforcement.");
2361                 return 0;
2362         }
2363         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2364         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2365         if (usr_qf_name || grp_qf_name) {
2366                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2367                         clear_opt(sb, USRQUOTA);
2368
2369                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2370                         clear_opt(sb, GRPQUOTA);
2371
2372                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2373                         ext4_msg(sb, KERN_ERR, "old and new quota "
2374                                         "format mixing");
2375                         return 0;
2376                 }
2377
2378                 if (!sbi->s_jquota_fmt) {
2379                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2380                                         "not specified");
2381                         return 0;
2382                 }
2383         }
2384 #endif
2385         if (test_opt(sb, DIOREAD_NOLOCK)) {
2386                 int blocksize =
2387                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2388                 if (blocksize < PAGE_SIZE)
2389                         ext4_msg(sb, KERN_WARNING, "Warning: mounting with an "
2390                                  "experimental mount option 'dioread_nolock' "
2391                                  "for blocksize < PAGE_SIZE");
2392         }
2393         return 1;
2394 }
2395
2396 static inline void ext4_show_quota_options(struct seq_file *seq,
2397                                            struct super_block *sb)
2398 {
2399 #if defined(CONFIG_QUOTA)
2400         struct ext4_sb_info *sbi = EXT4_SB(sb);
2401         char *usr_qf_name, *grp_qf_name;
2402
2403         if (sbi->s_jquota_fmt) {
2404                 char *fmtname = "";
2405
2406                 switch (sbi->s_jquota_fmt) {
2407                 case QFMT_VFS_OLD:
2408                         fmtname = "vfsold";
2409                         break;
2410                 case QFMT_VFS_V0:
2411                         fmtname = "vfsv0";
2412                         break;
2413                 case QFMT_VFS_V1:
2414                         fmtname = "vfsv1";
2415                         break;
2416                 }
2417                 seq_printf(seq, ",jqfmt=%s", fmtname);
2418         }
2419
2420         rcu_read_lock();
2421         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2422         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2423         if (usr_qf_name)
2424                 seq_show_option(seq, "usrjquota", usr_qf_name);
2425         if (grp_qf_name)
2426                 seq_show_option(seq, "grpjquota", grp_qf_name);
2427         rcu_read_unlock();
2428 #endif
2429 }
2430
2431 static const char *token2str(int token)
2432 {
2433         const struct match_token *t;
2434
2435         for (t = tokens; t->token != Opt_err; t++)
2436                 if (t->token == token && !strchr(t->pattern, '='))
2437                         break;
2438         return t->pattern;
2439 }
2440
2441 /*
2442  * Show an option if
2443  *  - it's set to a non-default value OR
2444  *  - if the per-sb default is different from the global default
2445  */
2446 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2447                               int nodefs)
2448 {
2449         struct ext4_sb_info *sbi = EXT4_SB(sb);
2450         struct ext4_super_block *es = sbi->s_es;
2451         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2452         const struct mount_opts *m;
2453         char sep = nodefs ? '\n' : ',';
2454
2455 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2456 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2457
2458         if (sbi->s_sb_block != 1)
2459                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2460
2461         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2462                 int want_set = m->flags & MOPT_SET;
2463                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2464                     (m->flags & MOPT_CLEAR_ERR) || m->flags & MOPT_SKIP)
2465                         continue;
2466                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2467                         continue; /* skip if same as the default */
2468                 if ((want_set &&
2469                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2470                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2471                         continue; /* select Opt_noFoo vs Opt_Foo */
2472                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2473         }
2474
2475         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2476             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2477                 SEQ_OPTS_PRINT("resuid=%u",
2478                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2479         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2480             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2481                 SEQ_OPTS_PRINT("resgid=%u",
2482                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2483         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2484         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2485                 SEQ_OPTS_PUTS("errors=remount-ro");
2486         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2487                 SEQ_OPTS_PUTS("errors=continue");
2488         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2489                 SEQ_OPTS_PUTS("errors=panic");
2490         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2491                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2492         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2493                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2494         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2495                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2496         if (sb->s_flags & SB_I_VERSION)
2497                 SEQ_OPTS_PUTS("i_version");
2498         if (nodefs || sbi->s_stripe)
2499                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2500         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2501                         (sbi->s_mount_opt ^ def_mount_opt)) {
2502                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2503                         SEQ_OPTS_PUTS("data=journal");
2504                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2505                         SEQ_OPTS_PUTS("data=ordered");
2506                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2507                         SEQ_OPTS_PUTS("data=writeback");
2508         }
2509         if (nodefs ||
2510             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2511                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2512                                sbi->s_inode_readahead_blks);
2513
2514         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2515                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2516                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2517         if (nodefs || sbi->s_max_dir_size_kb)
2518                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2519         if (test_opt(sb, DATA_ERR_ABORT))
2520                 SEQ_OPTS_PUTS("data_err=abort");
2521
2522         fscrypt_show_test_dummy_encryption(seq, sep, sb);
2523
2524         if (sb->s_flags & SB_INLINECRYPT)
2525                 SEQ_OPTS_PUTS("inlinecrypt");
2526
2527         if (test_opt(sb, DAX_ALWAYS)) {
2528                 if (IS_EXT2_SB(sb))
2529                         SEQ_OPTS_PUTS("dax");
2530                 else
2531                         SEQ_OPTS_PUTS("dax=always");
2532         } else if (test_opt2(sb, DAX_NEVER)) {
2533                 SEQ_OPTS_PUTS("dax=never");
2534         } else if (test_opt2(sb, DAX_INODE)) {
2535                 SEQ_OPTS_PUTS("dax=inode");
2536         }
2537
2538         ext4_show_quota_options(seq, sb);
2539         return 0;
2540 }
2541
2542 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2543 {
2544         return _ext4_show_options(seq, root->d_sb, 0);
2545 }
2546
2547 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2548 {
2549         struct super_block *sb = seq->private;
2550         int rc;
2551
2552         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2553         rc = _ext4_show_options(seq, sb, 1);
2554         seq_puts(seq, "\n");
2555         return rc;
2556 }
2557
2558 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2559                             int read_only)
2560 {
2561         struct ext4_sb_info *sbi = EXT4_SB(sb);
2562         int err = 0;
2563
2564         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2565                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2566                          "forcing read-only mode");
2567                 err = -EROFS;
2568                 goto done;
2569         }
2570         if (read_only)
2571                 goto done;
2572         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2573                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2574                          "running e2fsck is recommended");
2575         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2576                 ext4_msg(sb, KERN_WARNING,
2577                          "warning: mounting fs with errors, "
2578                          "running e2fsck is recommended");
2579         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2580                  le16_to_cpu(es->s_mnt_count) >=
2581                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2582                 ext4_msg(sb, KERN_WARNING,
2583                          "warning: maximal mount count reached, "
2584                          "running e2fsck is recommended");
2585         else if (le32_to_cpu(es->s_checkinterval) &&
2586                  (ext4_get_tstamp(es, s_lastcheck) +
2587                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2588                 ext4_msg(sb, KERN_WARNING,
2589                          "warning: checktime reached, "
2590                          "running e2fsck is recommended");
2591         if (!sbi->s_journal)
2592                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2593         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2594                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2595         le16_add_cpu(&es->s_mnt_count, 1);
2596         ext4_update_tstamp(es, s_mtime);
2597         if (sbi->s_journal)
2598                 ext4_set_feature_journal_needs_recovery(sb);
2599
2600         err = ext4_commit_super(sb, 1);
2601 done:
2602         if (test_opt(sb, DEBUG))
2603                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2604                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2605                         sb->s_blocksize,
2606                         sbi->s_groups_count,
2607                         EXT4_BLOCKS_PER_GROUP(sb),
2608                         EXT4_INODES_PER_GROUP(sb),
2609                         sbi->s_mount_opt, sbi->s_mount_opt2);
2610
2611         cleancache_init_fs(sb);
2612         return err;
2613 }
2614
2615 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2616 {
2617         struct ext4_sb_info *sbi = EXT4_SB(sb);
2618         struct flex_groups **old_groups, **new_groups;
2619         int size, i, j;
2620
2621         if (!sbi->s_log_groups_per_flex)
2622                 return 0;
2623
2624         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2625         if (size <= sbi->s_flex_groups_allocated)
2626                 return 0;
2627
2628         new_groups = kvzalloc(roundup_pow_of_two(size *
2629                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2630         if (!new_groups) {
2631                 ext4_msg(sb, KERN_ERR,
2632                          "not enough memory for %d flex group pointers", size);
2633                 return -ENOMEM;
2634         }
2635         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2636                 new_groups[i] = kvzalloc(roundup_pow_of_two(
2637                                          sizeof(struct flex_groups)),
2638                                          GFP_KERNEL);
2639                 if (!new_groups[i]) {
2640                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
2641                                 kvfree(new_groups[j]);
2642                         kvfree(new_groups);
2643                         ext4_msg(sb, KERN_ERR,
2644                                  "not enough memory for %d flex groups", size);
2645                         return -ENOMEM;
2646                 }
2647         }
2648         rcu_read_lock();
2649         old_groups = rcu_dereference(sbi->s_flex_groups);
2650         if (old_groups)
2651                 memcpy(new_groups, old_groups,
2652                        (sbi->s_flex_groups_allocated *
2653                         sizeof(struct flex_groups *)));
2654         rcu_read_unlock();
2655         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2656         sbi->s_flex_groups_allocated = size;
2657         if (old_groups)
2658                 ext4_kvfree_array_rcu(old_groups);
2659         return 0;
2660 }
2661
2662 static int ext4_fill_flex_info(struct super_block *sb)
2663 {
2664         struct ext4_sb_info *sbi = EXT4_SB(sb);
2665         struct ext4_group_desc *gdp = NULL;
2666         struct flex_groups *fg;
2667         ext4_group_t flex_group;
2668         int i, err;
2669
2670         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2671         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2672                 sbi->s_log_groups_per_flex = 0;
2673                 return 1;
2674         }
2675
2676         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2677         if (err)
2678                 goto failed;
2679
2680         for (i = 0; i < sbi->s_groups_count; i++) {
2681                 gdp = ext4_get_group_desc(sb, i, NULL);
2682
2683                 flex_group = ext4_flex_group(sbi, i);
2684                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2685                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2686                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2687                              &fg->free_clusters);
2688                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2689         }
2690
2691         return 1;
2692 failed:
2693         return 0;
2694 }
2695
2696 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2697                                    struct ext4_group_desc *gdp)
2698 {
2699         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2700         __u16 crc = 0;
2701         __le32 le_group = cpu_to_le32(block_group);
2702         struct ext4_sb_info *sbi = EXT4_SB(sb);
2703
2704         if (ext4_has_metadata_csum(sbi->s_sb)) {
2705                 /* Use new metadata_csum algorithm */
2706                 __u32 csum32;
2707                 __u16 dummy_csum = 0;
2708
2709                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2710                                      sizeof(le_group));
2711                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2712                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2713                                      sizeof(dummy_csum));
2714                 offset += sizeof(dummy_csum);
2715                 if (offset < sbi->s_desc_size)
2716                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2717                                              sbi->s_desc_size - offset);
2718
2719                 crc = csum32 & 0xFFFF;
2720                 goto out;
2721         }
2722
2723         /* old crc16 code */
2724         if (!ext4_has_feature_gdt_csum(sb))
2725                 return 0;
2726
2727         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2728         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2729         crc = crc16(crc, (__u8 *)gdp, offset);
2730         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2731         /* for checksum of struct ext4_group_desc do the rest...*/
2732         if (ext4_has_feature_64bit(sb) &&
2733             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2734                 crc = crc16(crc, (__u8 *)gdp + offset,
2735                             le16_to_cpu(sbi->s_es->s_desc_size) -
2736                                 offset);
2737
2738 out:
2739         return cpu_to_le16(crc);
2740 }
2741
2742 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2743                                 struct ext4_group_desc *gdp)
2744 {
2745         if (ext4_has_group_desc_csum(sb) &&
2746             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2747                 return 0;
2748
2749         return 1;
2750 }
2751
2752 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2753                               struct ext4_group_desc *gdp)
2754 {
2755         if (!ext4_has_group_desc_csum(sb))
2756                 return;
2757         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2758 }
2759
2760 /* Called at mount-time, super-block is locked */
2761 static int ext4_check_descriptors(struct super_block *sb,
2762                                   ext4_fsblk_t sb_block,
2763                                   ext4_group_t *first_not_zeroed)
2764 {
2765         struct ext4_sb_info *sbi = EXT4_SB(sb);
2766         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2767         ext4_fsblk_t last_block;
2768         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2769         ext4_fsblk_t block_bitmap;
2770         ext4_fsblk_t inode_bitmap;
2771         ext4_fsblk_t inode_table;
2772         int flexbg_flag = 0;
2773         ext4_group_t i, grp = sbi->s_groups_count;
2774
2775         if (ext4_has_feature_flex_bg(sb))
2776                 flexbg_flag = 1;
2777
2778         ext4_debug("Checking group descriptors");
2779
2780         for (i = 0; i < sbi->s_groups_count; i++) {
2781                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2782
2783                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2784                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2785                 else
2786                         last_block = first_block +
2787                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2788
2789                 if ((grp == sbi->s_groups_count) &&
2790                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2791                         grp = i;
2792
2793                 block_bitmap = ext4_block_bitmap(sb, gdp);
2794                 if (block_bitmap == sb_block) {
2795                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2796                                  "Block bitmap for group %u overlaps "
2797                                  "superblock", i);
2798                         if (!sb_rdonly(sb))
2799                                 return 0;
2800                 }
2801                 if (block_bitmap >= sb_block + 1 &&
2802                     block_bitmap <= last_bg_block) {
2803                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2804                                  "Block bitmap for group %u overlaps "
2805                                  "block group descriptors", i);
2806                         if (!sb_rdonly(sb))
2807                                 return 0;
2808                 }
2809                 if (block_bitmap < first_block || block_bitmap > last_block) {
2810                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2811                                "Block bitmap for group %u not in group "
2812                                "(block %llu)!", i, block_bitmap);
2813                         return 0;
2814                 }
2815                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2816                 if (inode_bitmap == sb_block) {
2817                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2818                                  "Inode bitmap for group %u overlaps "
2819                                  "superblock", i);
2820                         if (!sb_rdonly(sb))
2821                                 return 0;
2822                 }
2823                 if (inode_bitmap >= sb_block + 1 &&
2824                     inode_bitmap <= last_bg_block) {
2825                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2826                                  "Inode bitmap for group %u overlaps "
2827                                  "block group descriptors", i);
2828                         if (!sb_rdonly(sb))
2829                                 return 0;
2830                 }
2831                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2832                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2833                                "Inode bitmap for group %u not in group "
2834                                "(block %llu)!", i, inode_bitmap);
2835                         return 0;
2836                 }
2837                 inode_table = ext4_inode_table(sb, gdp);
2838                 if (inode_table == sb_block) {
2839                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2840                                  "Inode table for group %u overlaps "
2841                                  "superblock", i);
2842                         if (!sb_rdonly(sb))
2843                                 return 0;
2844                 }
2845                 if (inode_table >= sb_block + 1 &&
2846                     inode_table <= last_bg_block) {
2847                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2848                                  "Inode table for group %u overlaps "
2849                                  "block group descriptors", i);
2850                         if (!sb_rdonly(sb))
2851                                 return 0;
2852                 }
2853                 if (inode_table < first_block ||
2854                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2855                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2856                                "Inode table for group %u not in group "
2857                                "(block %llu)!", i, inode_table);
2858                         return 0;
2859                 }
2860                 ext4_lock_group(sb, i);
2861                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2862                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2863                                  "Checksum for group %u failed (%u!=%u)",
2864                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2865                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2866                         if (!sb_rdonly(sb)) {
2867                                 ext4_unlock_group(sb, i);
2868                                 return 0;
2869                         }
2870                 }
2871                 ext4_unlock_group(sb, i);
2872                 if (!flexbg_flag)
2873                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2874         }
2875         if (NULL != first_not_zeroed)
2876                 *first_not_zeroed = grp;
2877         return 1;
2878 }
2879
2880 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2881  * the superblock) which were deleted from all directories, but held open by
2882  * a process at the time of a crash.  We walk the list and try to delete these
2883  * inodes at recovery time (only with a read-write filesystem).
2884  *
2885  * In order to keep the orphan inode chain consistent during traversal (in
2886  * case of crash during recovery), we link each inode into the superblock
2887  * orphan list_head and handle it the same way as an inode deletion during
2888  * normal operation (which journals the operations for us).
2889  *
2890  * We only do an iget() and an iput() on each inode, which is very safe if we
2891  * accidentally point at an in-use or already deleted inode.  The worst that
2892  * can happen in this case is that we get a "bit already cleared" message from
2893  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2894  * e2fsck was run on this filesystem, and it must have already done the orphan
2895  * inode cleanup for us, so we can safely abort without any further action.
2896  */
2897 static void ext4_orphan_cleanup(struct super_block *sb,
2898                                 struct ext4_super_block *es)
2899 {
2900         unsigned int s_flags = sb->s_flags;
2901         int ret, nr_orphans = 0, nr_truncates = 0;
2902 #ifdef CONFIG_QUOTA
2903         int quota_update = 0;
2904         int i;
2905 #endif
2906         if (!es->s_last_orphan) {
2907                 jbd_debug(4, "no orphan inodes to clean up\n");
2908                 return;
2909         }
2910
2911         if (bdev_read_only(sb->s_bdev)) {
2912                 ext4_msg(sb, KERN_ERR, "write access "
2913                         "unavailable, skipping orphan cleanup");
2914                 return;
2915         }
2916
2917         /* Check if feature set would not allow a r/w mount */
2918         if (!ext4_feature_set_ok(sb, 0)) {
2919                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2920                          "unknown ROCOMPAT features");
2921                 return;
2922         }
2923
2924         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2925                 /* don't clear list on RO mount w/ errors */
2926                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2927                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2928                                   "clearing orphan list.\n");
2929                         es->s_last_orphan = 0;
2930                 }
2931                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2932                 return;
2933         }
2934
2935         if (s_flags & SB_RDONLY) {
2936                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2937                 sb->s_flags &= ~SB_RDONLY;
2938         }
2939 #ifdef CONFIG_QUOTA
2940         /* Needed for iput() to work correctly and not trash data */
2941         sb->s_flags |= SB_ACTIVE;
2942
2943         /*
2944          * Turn on quotas which were not enabled for read-only mounts if
2945          * filesystem has quota feature, so that they are updated correctly.
2946          */
2947         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2948                 int ret = ext4_enable_quotas(sb);
2949
2950                 if (!ret)
2951                         quota_update = 1;
2952                 else
2953                         ext4_msg(sb, KERN_ERR,
2954                                 "Cannot turn on quotas: error %d", ret);
2955         }
2956
2957         /* Turn on journaled quotas used for old sytle */
2958         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2959                 if (EXT4_SB(sb)->s_qf_names[i]) {
2960                         int ret = ext4_quota_on_mount(sb, i);
2961
2962                         if (!ret)
2963                                 quota_update = 1;
2964                         else
2965                                 ext4_msg(sb, KERN_ERR,
2966                                         "Cannot turn on journaled "
2967                                         "quota: type %d: error %d", i, ret);
2968                 }
2969         }
2970 #endif
2971
2972         while (es->s_last_orphan) {
2973                 struct inode *inode;
2974
2975                 /*
2976                  * We may have encountered an error during cleanup; if
2977                  * so, skip the rest.
2978                  */
2979                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2980                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2981                         es->s_last_orphan = 0;
2982                         break;
2983                 }
2984
2985                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2986                 if (IS_ERR(inode)) {
2987                         es->s_last_orphan = 0;
2988                         break;
2989                 }
2990
2991                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2992                 dquot_initialize(inode);
2993                 if (inode->i_nlink) {
2994                         if (test_opt(sb, DEBUG))
2995                                 ext4_msg(sb, KERN_DEBUG,
2996                                         "%s: truncating inode %lu to %lld bytes",
2997                                         __func__, inode->i_ino, inode->i_size);
2998                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2999                                   inode->i_ino, inode->i_size);
3000                         inode_lock(inode);
3001                         truncate_inode_pages(inode->i_mapping, inode->i_size);
3002                         ret = ext4_truncate(inode);
3003                         if (ret)
3004                                 ext4_std_error(inode->i_sb, ret);
3005                         inode_unlock(inode);
3006                         nr_truncates++;
3007                 } else {
3008                         if (test_opt(sb, DEBUG))
3009                                 ext4_msg(sb, KERN_DEBUG,
3010                                         "%s: deleting unreferenced inode %lu",
3011                                         __func__, inode->i_ino);
3012                         jbd_debug(2, "deleting unreferenced inode %lu\n",
3013                                   inode->i_ino);
3014                         nr_orphans++;
3015                 }
3016                 iput(inode);  /* The delete magic happens here! */
3017         }
3018
3019 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
3020
3021         if (nr_orphans)
3022                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
3023                        PLURAL(nr_orphans));
3024         if (nr_truncates)
3025                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
3026                        PLURAL(nr_truncates));
3027 #ifdef CONFIG_QUOTA
3028         /* Turn off quotas if they were enabled for orphan cleanup */
3029         if (quota_update) {
3030                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3031                         if (sb_dqopt(sb)->files[i])
3032                                 dquot_quota_off(sb, i);
3033                 }
3034         }
3035 #endif
3036         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
3037 }
3038
3039 /*
3040  * Maximal extent format file size.
3041  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3042  * extent format containers, within a sector_t, and within i_blocks
3043  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3044  * so that won't be a limiting factor.
3045  *
3046  * However there is other limiting factor. We do store extents in the form
3047  * of starting block and length, hence the resulting length of the extent
3048  * covering maximum file size must fit into on-disk format containers as
3049  * well. Given that length is always by 1 unit bigger than max unit (because
3050  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3051  *
3052  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3053  */
3054 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3055 {
3056         loff_t res;
3057         loff_t upper_limit = MAX_LFS_FILESIZE;
3058
3059         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3060
3061         if (!has_huge_files) {
3062                 upper_limit = (1LL << 32) - 1;
3063
3064                 /* total blocks in file system block size */
3065                 upper_limit >>= (blkbits - 9);
3066                 upper_limit <<= blkbits;
3067         }
3068
3069         /*
3070          * 32-bit extent-start container, ee_block. We lower the maxbytes
3071          * by one fs block, so ee_len can cover the extent of maximum file
3072          * size
3073          */
3074         res = (1LL << 32) - 1;
3075         res <<= blkbits;
3076
3077         /* Sanity check against vm- & vfs- imposed limits */
3078         if (res > upper_limit)
3079                 res = upper_limit;
3080
3081         return res;
3082 }
3083
3084 /*
3085  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3086  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3087  * We need to be 1 filesystem block less than the 2^48 sector limit.
3088  */
3089 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3090 {
3091         loff_t res = EXT4_NDIR_BLOCKS;
3092         int meta_blocks;
3093         loff_t upper_limit;
3094         /* This is calculated to be the largest file size for a dense, block
3095          * mapped file such that the file's total number of 512-byte sectors,
3096          * including data and all indirect blocks, does not exceed (2^48 - 1).
3097          *
3098          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3099          * number of 512-byte sectors of the file.
3100          */
3101
3102         if (!has_huge_files) {
3103                 /*
3104                  * !has_huge_files or implies that the inode i_block field
3105                  * represents total file blocks in 2^32 512-byte sectors ==
3106                  * size of vfs inode i_blocks * 8
3107                  */
3108                 upper_limit = (1LL << 32) - 1;
3109
3110                 /* total blocks in file system block size */
3111                 upper_limit >>= (bits - 9);
3112
3113         } else {
3114                 /*
3115                  * We use 48 bit ext4_inode i_blocks
3116                  * With EXT4_HUGE_FILE_FL set the i_blocks
3117                  * represent total number of blocks in
3118                  * file system block size
3119                  */
3120                 upper_limit = (1LL << 48) - 1;
3121
3122         }
3123
3124         /* indirect blocks */
3125         meta_blocks = 1;
3126         /* double indirect blocks */
3127         meta_blocks += 1 + (1LL << (bits-2));
3128         /* tripple indirect blocks */
3129         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
3130
3131         upper_limit -= meta_blocks;
3132         upper_limit <<= bits;
3133
3134         res += 1LL << (bits-2);
3135         res += 1LL << (2*(bits-2));
3136         res += 1LL << (3*(bits-2));
3137         res <<= bits;
3138         if (res > upper_limit)
3139                 res = upper_limit;
3140
3141         if (res > MAX_LFS_FILESIZE)
3142                 res = MAX_LFS_FILESIZE;
3143
3144         return res;
3145 }
3146
3147 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3148                                    ext4_fsblk_t logical_sb_block, int nr)
3149 {
3150         struct ext4_sb_info *sbi = EXT4_SB(sb);
3151         ext4_group_t bg, first_meta_bg;
3152         int has_super = 0;
3153
3154         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3155
3156         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3157                 return logical_sb_block + nr + 1;
3158         bg = sbi->s_desc_per_block * nr;
3159         if (ext4_bg_has_super(sb, bg))
3160                 has_super = 1;
3161
3162         /*
3163          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3164          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3165          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3166          * compensate.
3167          */
3168         if (sb->s_blocksize == 1024 && nr == 0 &&
3169             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3170                 has_super++;
3171
3172         return (has_super + ext4_group_first_block_no(sb, bg));
3173 }
3174
3175 /**
3176  * ext4_get_stripe_size: Get the stripe size.
3177  * @sbi: In memory super block info
3178  *
3179  * If we have specified it via mount option, then
3180  * use the mount option value. If the value specified at mount time is
3181  * greater than the blocks per group use the super block value.
3182  * If the super block value is greater than blocks per group return 0.
3183  * Allocator needs it be less than blocks per group.
3184  *
3185  */
3186 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3187 {
3188         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3189         unsigned long stripe_width =
3190                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3191         int ret;
3192
3193         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3194                 ret = sbi->s_stripe;
3195         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3196                 ret = stripe_width;
3197         else if (stride && stride <= sbi->s_blocks_per_group)
3198                 ret = stride;
3199         else
3200                 ret = 0;
3201
3202         /*
3203          * If the stripe width is 1, this makes no sense and
3204          * we set it to 0 to turn off stripe handling code.
3205          */
3206         if (ret <= 1)
3207                 ret = 0;
3208
3209         return ret;
3210 }
3211
3212 /*
3213  * Check whether this filesystem can be mounted based on
3214  * the features present and the RDONLY/RDWR mount requested.
3215  * Returns 1 if this filesystem can be mounted as requested,
3216  * 0 if it cannot be.
3217  */
3218 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
3219 {
3220         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3221                 ext4_msg(sb, KERN_ERR,
3222                         "Couldn't mount because of "
3223                         "unsupported optional features (%x)",
3224                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3225                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3226                 return 0;
3227         }
3228
3229 #ifndef CONFIG_UNICODE
3230         if (ext4_has_feature_casefold(sb)) {
3231                 ext4_msg(sb, KERN_ERR,
3232                          "Filesystem with casefold feature cannot be "
3233                          "mounted without CONFIG_UNICODE");
3234                 return 0;
3235         }
3236 #endif
3237
3238         if (readonly)
3239                 return 1;
3240
3241         if (ext4_has_feature_readonly(sb)) {
3242                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3243                 sb->s_flags |= SB_RDONLY;
3244                 return 1;
3245         }
3246
3247         /* Check that feature set is OK for a read-write mount */
3248         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3249                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3250                          "unsupported optional features (%x)",
3251                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3252                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3253                 return 0;
3254         }
3255         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3256                 ext4_msg(sb, KERN_ERR,
3257                          "Can't support bigalloc feature without "
3258                          "extents feature\n");
3259                 return 0;
3260         }
3261
3262 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3263         if (!readonly && (ext4_has_feature_quota(sb) ||
3264                           ext4_has_feature_project(sb))) {
3265                 ext4_msg(sb, KERN_ERR,
3266                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3267                 return 0;
3268         }
3269 #endif  /* CONFIG_QUOTA */
3270         return 1;
3271 }
3272
3273 /*
3274  * This function is called once a day if we have errors logged
3275  * on the file system
3276  */
3277 static void print_daily_error_info(struct timer_list *t)
3278 {
3279         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3280         struct super_block *sb = sbi->s_sb;
3281         struct ext4_super_block *es = sbi->s_es;
3282
3283         if (es->s_error_count)
3284                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3285                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3286                          le32_to_cpu(es->s_error_count));
3287         if (es->s_first_error_time) {
3288                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3289                        sb->s_id,
3290                        ext4_get_tstamp(es, s_first_error_time),
3291                        (int) sizeof(es->s_first_error_func),
3292                        es->s_first_error_func,
3293                        le32_to_cpu(es->s_first_error_line));
3294                 if (es->s_first_error_ino)
3295                         printk(KERN_CONT ": inode %u",
3296                                le32_to_cpu(es->s_first_error_ino));
3297                 if (es->s_first_error_block)
3298                         printk(KERN_CONT ": block %llu", (unsigned long long)
3299                                le64_to_cpu(es->s_first_error_block));
3300                 printk(KERN_CONT "\n");
3301         }
3302         if (es->s_last_error_time) {
3303                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3304                        sb->s_id,
3305                        ext4_get_tstamp(es, s_last_error_time),
3306                        (int) sizeof(es->s_last_error_func),
3307                        es->s_last_error_func,
3308                        le32_to_cpu(es->s_last_error_line));
3309                 if (es->s_last_error_ino)
3310                         printk(KERN_CONT ": inode %u",
3311                                le32_to_cpu(es->s_last_error_ino));
3312                 if (es->s_last_error_block)
3313                         printk(KERN_CONT ": block %llu", (unsigned long long)
3314                                le64_to_cpu(es->s_last_error_block));
3315                 printk(KERN_CONT "\n");
3316         }
3317         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3318 }
3319
3320 /* Find next suitable group and run ext4_init_inode_table */
3321 static int ext4_run_li_request(struct ext4_li_request *elr)
3322 {
3323         struct ext4_group_desc *gdp = NULL;
3324         struct super_block *sb = elr->lr_super;
3325         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3326         ext4_group_t group = elr->lr_next_group;
3327         unsigned long timeout = 0;
3328         unsigned int prefetch_ios = 0;
3329         int ret = 0;
3330
3331         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3332                 elr->lr_next_group = ext4_mb_prefetch(sb, group,
3333                                 EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3334                 if (prefetch_ios)
3335                         ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3336                                               prefetch_ios);
3337                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3338                                             prefetch_ios);
3339                 if (group >= elr->lr_next_group) {
3340                         ret = 1;
3341                         if (elr->lr_first_not_zeroed != ngroups &&
3342                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3343                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3344                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3345                                 ret = 0;
3346                         }
3347                 }
3348                 return ret;
3349         }
3350
3351         for (; group < ngroups; group++) {
3352                 gdp = ext4_get_group_desc(sb, group, NULL);
3353                 if (!gdp) {
3354                         ret = 1;
3355                         break;
3356                 }
3357
3358                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3359                         break;
3360         }
3361
3362         if (group >= ngroups)
3363                 ret = 1;
3364
3365         if (!ret) {
3366                 timeout = jiffies;
3367                 ret = ext4_init_inode_table(sb, group,
3368                                             elr->lr_timeout ? 0 : 1);
3369                 trace_ext4_lazy_itable_init(sb, group);
3370                 if (elr->lr_timeout == 0) {
3371                         timeout = (jiffies - timeout) *
3372                                 EXT4_SB(elr->lr_super)->s_li_wait_mult;
3373                         elr->lr_timeout = timeout;
3374                 }
3375                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3376                 elr->lr_next_group = group + 1;
3377         }
3378         return ret;
3379 }
3380
3381 /*
3382  * Remove lr_request from the list_request and free the
3383  * request structure. Should be called with li_list_mtx held
3384  */
3385 static void ext4_remove_li_request(struct ext4_li_request *elr)
3386 {
3387         if (!elr)
3388                 return;
3389
3390         list_del(&elr->lr_request);
3391         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3392         kfree(elr);
3393 }
3394
3395 static void ext4_unregister_li_request(struct super_block *sb)
3396 {
3397         mutex_lock(&ext4_li_mtx);
3398         if (!ext4_li_info) {
3399                 mutex_unlock(&ext4_li_mtx);
3400                 return;
3401         }
3402
3403         mutex_lock(&ext4_li_info->li_list_mtx);
3404         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3405         mutex_unlock(&ext4_li_info->li_list_mtx);
3406         mutex_unlock(&ext4_li_mtx);
3407 }
3408
3409 static struct task_struct *ext4_lazyinit_task;
3410
3411 /*
3412  * This is the function where ext4lazyinit thread lives. It walks
3413  * through the request list searching for next scheduled filesystem.
3414  * When such a fs is found, run the lazy initialization request
3415  * (ext4_rn_li_request) and keep track of the time spend in this
3416  * function. Based on that time we compute next schedule time of
3417  * the request. When walking through the list is complete, compute
3418  * next waking time and put itself into sleep.
3419  */
3420 static int ext4_lazyinit_thread(void *arg)
3421 {
3422         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3423         struct list_head *pos, *n;
3424         struct ext4_li_request *elr;
3425         unsigned long next_wakeup, cur;
3426
3427         BUG_ON(NULL == eli);
3428
3429 cont_thread:
3430         while (true) {
3431                 next_wakeup = MAX_JIFFY_OFFSET;
3432
3433                 mutex_lock(&eli->li_list_mtx);
3434                 if (list_empty(&eli->li_request_list)) {
3435                         mutex_unlock(&eli->li_list_mtx);
3436                         goto exit_thread;
3437                 }
3438                 list_for_each_safe(pos, n, &eli->li_request_list) {
3439                         int err = 0;
3440                         int progress = 0;
3441                         elr = list_entry(pos, struct ext4_li_request,
3442                                          lr_request);
3443
3444                         if (time_before(jiffies, elr->lr_next_sched)) {
3445                                 if (time_before(elr->lr_next_sched, next_wakeup))
3446                                         next_wakeup = elr->lr_next_sched;
3447                                 continue;
3448                         }
3449                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3450                                 if (sb_start_write_trylock(elr->lr_super)) {
3451                                         progress = 1;
3452                                         /*
3453                                          * We hold sb->s_umount, sb can not
3454                                          * be removed from the list, it is
3455                                          * now safe to drop li_list_mtx
3456                                          */
3457                                         mutex_unlock(&eli->li_list_mtx);
3458                                         err = ext4_run_li_request(elr);
3459                                         sb_end_write(elr->lr_super);
3460                                         mutex_lock(&eli->li_list_mtx);
3461                                         n = pos->next;
3462                                 }
3463                                 up_read((&elr->lr_super->s_umount));
3464                         }
3465                         /* error, remove the lazy_init job */
3466                         if (err) {
3467                                 ext4_remove_li_request(elr);
3468                                 continue;
3469                         }
3470                         if (!progress) {
3471                                 elr->lr_next_sched = jiffies +
3472                                         (prandom_u32()
3473                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3474                         }
3475                         if (time_before(elr->lr_next_sched, next_wakeup))
3476                                 next_wakeup = elr->lr_next_sched;
3477                 }
3478                 mutex_unlock(&eli->li_list_mtx);
3479
3480                 try_to_freeze();
3481
3482                 cur = jiffies;
3483                 if ((time_after_eq(cur, next_wakeup)) ||
3484                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3485                         cond_resched();
3486                         continue;
3487                 }
3488
3489                 schedule_timeout_interruptible(next_wakeup - cur);
3490
3491                 if (kthread_should_stop()) {
3492                         ext4_clear_request_list();
3493                         goto exit_thread;
3494                 }
3495         }
3496
3497 exit_thread:
3498         /*
3499          * It looks like the request list is empty, but we need
3500          * to check it under the li_list_mtx lock, to prevent any
3501          * additions into it, and of course we should lock ext4_li_mtx
3502          * to atomically free the list and ext4_li_info, because at
3503          * this point another ext4 filesystem could be registering
3504          * new one.
3505          */
3506         mutex_lock(&ext4_li_mtx);
3507         mutex_lock(&eli->li_list_mtx);
3508         if (!list_empty(&eli->li_request_list)) {
3509                 mutex_unlock(&eli->li_list_mtx);
3510                 mutex_unlock(&ext4_li_mtx);
3511                 goto cont_thread;
3512         }
3513         mutex_unlock(&eli->li_list_mtx);
3514         kfree(ext4_li_info);
3515         ext4_li_info = NULL;
3516         mutex_unlock(&ext4_li_mtx);
3517
3518         return 0;
3519 }
3520
3521 static void ext4_clear_request_list(void)
3522 {
3523         struct list_head *pos, *n;
3524         struct ext4_li_request *elr;
3525
3526         mutex_lock(&ext4_li_info->li_list_mtx);
3527         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3528                 elr = list_entry(pos, struct ext4_li_request,
3529                                  lr_request);
3530                 ext4_remove_li_request(elr);
3531         }
3532         mutex_unlock(&ext4_li_info->li_list_mtx);
3533 }
3534
3535 static int ext4_run_lazyinit_thread(void)
3536 {
3537         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3538                                          ext4_li_info, "ext4lazyinit");
3539         if (IS_ERR(ext4_lazyinit_task)) {
3540                 int err = PTR_ERR(ext4_lazyinit_task);
3541                 ext4_clear_request_list();
3542                 kfree(ext4_li_info);
3543                 ext4_li_info = NULL;
3544                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3545                                  "initialization thread\n",
3546                                  err);
3547                 return err;
3548         }
3549         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3550         return 0;
3551 }
3552
3553 /*
3554  * Check whether it make sense to run itable init. thread or not.
3555  * If there is at least one uninitialized inode table, return
3556  * corresponding group number, else the loop goes through all
3557  * groups and return total number of groups.
3558  */
3559 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3560 {
3561         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3562         struct ext4_group_desc *gdp = NULL;
3563
3564         if (!ext4_has_group_desc_csum(sb))
3565                 return ngroups;
3566
3567         for (group = 0; group < ngroups; group++) {
3568                 gdp = ext4_get_group_desc(sb, group, NULL);
3569                 if (!gdp)
3570                         continue;
3571
3572                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3573                         break;
3574         }
3575
3576         return group;
3577 }
3578
3579 static int ext4_li_info_new(void)
3580 {
3581         struct ext4_lazy_init *eli = NULL;
3582
3583         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3584         if (!eli)
3585                 return -ENOMEM;
3586
3587         INIT_LIST_HEAD(&eli->li_request_list);
3588         mutex_init(&eli->li_list_mtx);
3589
3590         eli->li_state |= EXT4_LAZYINIT_QUIT;
3591
3592         ext4_li_info = eli;
3593
3594         return 0;
3595 }
3596
3597 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3598                                             ext4_group_t start)
3599 {
3600         struct ext4_li_request *elr;
3601
3602         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3603         if (!elr)
3604                 return NULL;
3605
3606         elr->lr_super = sb;
3607         elr->lr_first_not_zeroed = start;
3608         if (test_opt(sb, PREFETCH_BLOCK_BITMAPS))
3609                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3610         else {
3611                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3612                 elr->lr_next_group = start;
3613         }
3614
3615         /*
3616          * Randomize first schedule time of the request to
3617          * spread the inode table initialization requests
3618          * better.
3619          */
3620         elr->lr_next_sched = jiffies + (prandom_u32() %
3621                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3622         return elr;
3623 }
3624
3625 int ext4_register_li_request(struct super_block *sb,
3626                              ext4_group_t first_not_zeroed)
3627 {
3628         struct ext4_sb_info *sbi = EXT4_SB(sb);
3629         struct ext4_li_request *elr = NULL;
3630         ext4_group_t ngroups = sbi->s_groups_count;
3631         int ret = 0;
3632
3633         mutex_lock(&ext4_li_mtx);
3634         if (sbi->s_li_request != NULL) {
3635                 /*
3636                  * Reset timeout so it can be computed again, because
3637                  * s_li_wait_mult might have changed.
3638                  */
3639                 sbi->s_li_request->lr_timeout = 0;
3640                 goto out;
3641         }
3642
3643         if (!test_opt(sb, PREFETCH_BLOCK_BITMAPS) &&
3644             (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3645              !test_opt(sb, INIT_INODE_TABLE)))
3646                 goto out;
3647
3648         elr = ext4_li_request_new(sb, first_not_zeroed);
3649         if (!elr) {
3650                 ret = -ENOMEM;
3651                 goto out;
3652         }
3653
3654         if (NULL == ext4_li_info) {
3655                 ret = ext4_li_info_new();
3656                 if (ret)
3657                         goto out;
3658         }
3659
3660         mutex_lock(&ext4_li_info->li_list_mtx);
3661         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3662         mutex_unlock(&ext4_li_info->li_list_mtx);
3663
3664         sbi->s_li_request = elr;
3665         /*
3666          * set elr to NULL here since it has been inserted to
3667          * the request_list and the removal and free of it is
3668          * handled by ext4_clear_request_list from now on.
3669          */
3670         elr = NULL;
3671
3672         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3673                 ret = ext4_run_lazyinit_thread();
3674                 if (ret)
3675                         goto out;
3676         }
3677 out:
3678         mutex_unlock(&ext4_li_mtx);
3679         if (ret)
3680                 kfree(elr);
3681         return ret;
3682 }
3683
3684 /*
3685  * We do not need to lock anything since this is called on
3686  * module unload.
3687  */
3688 static void ext4_destroy_lazyinit_thread(void)
3689 {
3690         /*
3691          * If thread exited earlier
3692          * there's nothing to be done.
3693          */
3694         if (!ext4_li_info || !ext4_lazyinit_task)
3695                 return;
3696
3697         kthread_stop(ext4_lazyinit_task);
3698 }
3699
3700 static int set_journal_csum_feature_set(struct super_block *sb)
3701 {
3702         int ret = 1;
3703         int compat, incompat;
3704         struct ext4_sb_info *sbi = EXT4_SB(sb);
3705
3706         if (ext4_has_metadata_csum(sb)) {
3707                 /* journal checksum v3 */
3708                 compat = 0;
3709                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3710         } else {
3711                 /* journal checksum v1 */
3712                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3713                 incompat = 0;
3714         }
3715
3716         jbd2_journal_clear_features(sbi->s_journal,
3717                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3718                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3719                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3720         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3721                 ret = jbd2_journal_set_features(sbi->s_journal,
3722                                 compat, 0,
3723                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3724                                 incompat);
3725         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3726                 ret = jbd2_journal_set_features(sbi->s_journal,
3727                                 compat, 0,
3728                                 incompat);
3729                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3730                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3731         } else {
3732                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3733                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3734         }
3735
3736         return ret;
3737 }
3738
3739 /*
3740  * Note: calculating the overhead so we can be compatible with
3741  * historical BSD practice is quite difficult in the face of
3742  * clusters/bigalloc.  This is because multiple metadata blocks from
3743  * different block group can end up in the same allocation cluster.
3744  * Calculating the exact overhead in the face of clustered allocation
3745  * requires either O(all block bitmaps) in memory or O(number of block
3746  * groups**2) in time.  We will still calculate the superblock for
3747  * older file systems --- and if we come across with a bigalloc file
3748  * system with zero in s_overhead_clusters the estimate will be close to
3749  * correct especially for very large cluster sizes --- but for newer
3750  * file systems, it's better to calculate this figure once at mkfs
3751  * time, and store it in the superblock.  If the superblock value is
3752  * present (even for non-bigalloc file systems), we will use it.
3753  */
3754 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3755                           char *buf)
3756 {
3757         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3758         struct ext4_group_desc  *gdp;
3759         ext4_fsblk_t            first_block, last_block, b;
3760         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3761         int                     s, j, count = 0;
3762
3763         if (!ext4_has_feature_bigalloc(sb))
3764                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3765                         sbi->s_itb_per_group + 2);
3766
3767         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3768                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3769         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3770         for (i = 0; i < ngroups; i++) {
3771                 gdp = ext4_get_group_desc(sb, i, NULL);
3772                 b = ext4_block_bitmap(sb, gdp);
3773                 if (b >= first_block && b <= last_block) {
3774                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3775                         count++;
3776                 }
3777                 b = ext4_inode_bitmap(sb, gdp);
3778                 if (b >= first_block && b <= last_block) {
3779                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3780                         count++;
3781                 }
3782                 b = ext4_inode_table(sb, gdp);
3783                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3784                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3785                                 int c = EXT4_B2C(sbi, b - first_block);
3786                                 ext4_set_bit(c, buf);
3787                                 count++;
3788                         }
3789                 if (i != grp)
3790                         continue;
3791                 s = 0;
3792                 if (ext4_bg_has_super(sb, grp)) {
3793                         ext4_set_bit(s++, buf);
3794                         count++;
3795                 }
3796                 j = ext4_bg_num_gdb(sb, grp);
3797                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3798                         ext4_error(sb, "Invalid number of block group "
3799                                    "descriptor blocks: %d", j);
3800                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3801                 }
3802                 count += j;
3803                 for (; j > 0; j--)
3804                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3805         }
3806         if (!count)
3807                 return 0;
3808         return EXT4_CLUSTERS_PER_GROUP(sb) -
3809                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3810 }
3811
3812 /*
3813  * Compute the overhead and stash it in sbi->s_overhead
3814  */
3815 int ext4_calculate_overhead(struct super_block *sb)
3816 {
3817         struct ext4_sb_info *sbi = EXT4_SB(sb);
3818         struct ext4_super_block *es = sbi->s_es;
3819         struct inode *j_inode;
3820         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3821         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3822         ext4_fsblk_t overhead = 0;
3823         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3824
3825         if (!buf)
3826                 return -ENOMEM;
3827
3828         /*
3829          * Compute the overhead (FS structures).  This is constant
3830          * for a given filesystem unless the number of block groups
3831          * changes so we cache the previous value until it does.
3832          */
3833
3834         /*
3835          * All of the blocks before first_data_block are overhead
3836          */
3837         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3838
3839         /*
3840          * Add the overhead found in each block group
3841          */
3842         for (i = 0; i < ngroups; i++) {
3843                 int blks;
3844
3845                 blks = count_overhead(sb, i, buf);
3846                 overhead += blks;
3847                 if (blks)
3848                         memset(buf, 0, PAGE_SIZE);
3849                 cond_resched();
3850         }
3851
3852         /*
3853          * Add the internal journal blocks whether the journal has been
3854          * loaded or not
3855          */
3856         if (sbi->s_journal && !sbi->s_journal_bdev)
3857                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3858         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3859                 /* j_inum for internal journal is non-zero */
3860                 j_inode = ext4_get_journal_inode(sb, j_inum);
3861                 if (j_inode) {
3862                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3863                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3864                         iput(j_inode);
3865                 } else {
3866                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3867                 }
3868         }
3869         sbi->s_overhead = overhead;
3870         smp_wmb();
3871         free_page((unsigned long) buf);
3872         return 0;
3873 }
3874
3875 static void ext4_set_resv_clusters(struct super_block *sb)
3876 {
3877         ext4_fsblk_t resv_clusters;
3878         struct ext4_sb_info *sbi = EXT4_SB(sb);
3879
3880         /*
3881          * There's no need to reserve anything when we aren't using extents.
3882          * The space estimates are exact, there are no unwritten extents,
3883          * hole punching doesn't need new metadata... This is needed especially
3884          * to keep ext2/3 backward compatibility.
3885          */
3886         if (!ext4_has_feature_extents(sb))
3887                 return;
3888         /*
3889          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3890          * This should cover the situations where we can not afford to run
3891          * out of space like for example punch hole, or converting
3892          * unwritten extents in delalloc path. In most cases such
3893          * allocation would require 1, or 2 blocks, higher numbers are
3894          * very rare.
3895          */
3896         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3897                          sbi->s_cluster_bits);
3898
3899         do_div(resv_clusters, 50);
3900         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3901
3902         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3903 }
3904
3905 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3906 {
3907         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3908         char *orig_data = kstrdup(data, GFP_KERNEL);
3909         struct buffer_head *bh, **group_desc;
3910         struct ext4_super_block *es = NULL;
3911         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3912         struct flex_groups **flex_groups;
3913         ext4_fsblk_t block;
3914         ext4_fsblk_t sb_block = get_sb_block(&data);
3915         ext4_fsblk_t logical_sb_block;
3916         unsigned long offset = 0;
3917         unsigned long journal_devnum = 0;
3918         unsigned long def_mount_opts;
3919         struct inode *root;
3920         const char *descr;
3921         int ret = -ENOMEM;
3922         int blocksize, clustersize;
3923         unsigned int db_count;
3924         unsigned int i;
3925         int needs_recovery, has_huge_files;
3926         __u64 blocks_count;
3927         int err = 0;
3928         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3929         ext4_group_t first_not_zeroed;
3930
3931         if ((data && !orig_data) || !sbi)
3932                 goto out_free_base;
3933
3934         sbi->s_daxdev = dax_dev;
3935         sbi->s_blockgroup_lock =
3936                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3937         if (!sbi->s_blockgroup_lock)
3938                 goto out_free_base;
3939
3940         sb->s_fs_info = sbi;
3941         sbi->s_sb = sb;
3942         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3943         sbi->s_sb_block = sb_block;
3944         if (sb->s_bdev->bd_part)
3945                 sbi->s_sectors_written_start =
3946                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
3947
3948         /* Cleanup superblock name */
3949         strreplace(sb->s_id, '/', '!');
3950
3951         /* -EINVAL is default */
3952         ret = -EINVAL;
3953         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3954         if (!blocksize) {
3955                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3956                 goto out_fail;
3957         }
3958
3959         /*
3960          * The ext4 superblock will not be buffer aligned for other than 1kB
3961          * block sizes.  We need to calculate the offset from buffer start.
3962          */
3963         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3964                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3965                 offset = do_div(logical_sb_block, blocksize);
3966         } else {
3967                 logical_sb_block = sb_block;
3968         }
3969
3970         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
3971         if (IS_ERR(bh)) {
3972                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3973                 ret = PTR_ERR(bh);
3974                 bh = NULL;
3975                 goto out_fail;
3976         }
3977         /*
3978          * Note: s_es must be initialized as soon as possible because
3979          *       some ext4 macro-instructions depend on its value
3980          */
3981         es = (struct ext4_super_block *) (bh->b_data + offset);
3982         sbi->s_es = es;
3983         sb->s_magic = le16_to_cpu(es->s_magic);
3984         if (sb->s_magic != EXT4_SUPER_MAGIC)
3985                 goto cantfind_ext4;
3986         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3987
3988         /* Warn if metadata_csum and gdt_csum are both set. */
3989         if (ext4_has_feature_metadata_csum(sb) &&
3990             ext4_has_feature_gdt_csum(sb))
3991                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3992                              "redundant flags; please run fsck.");
3993
3994         /* Check for a known checksum algorithm */
3995         if (!ext4_verify_csum_type(sb, es)) {
3996                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3997                          "unknown checksum algorithm.");
3998                 silent = 1;
3999                 goto cantfind_ext4;
4000         }
4001
4002         /* Load the checksum driver */
4003         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4004         if (IS_ERR(sbi->s_chksum_driver)) {
4005                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4006                 ret = PTR_ERR(sbi->s_chksum_driver);
4007                 sbi->s_chksum_driver = NULL;
4008                 goto failed_mount;
4009         }
4010
4011         /* Check superblock checksum */
4012         if (!ext4_superblock_csum_verify(sb, es)) {
4013                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4014                          "invalid superblock checksum.  Run e2fsck?");
4015                 silent = 1;
4016                 ret = -EFSBADCRC;
4017                 goto cantfind_ext4;
4018         }
4019
4020         /* Precompute checksum seed for all metadata */
4021         if (ext4_has_feature_csum_seed(sb))
4022                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4023         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4024                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4025                                                sizeof(es->s_uuid));
4026
4027         /* Set defaults before we parse the mount options */
4028         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4029         set_opt(sb, INIT_INODE_TABLE);
4030         if (def_mount_opts & EXT4_DEFM_DEBUG)
4031                 set_opt(sb, DEBUG);
4032         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4033                 set_opt(sb, GRPID);
4034         if (def_mount_opts & EXT4_DEFM_UID16)
4035                 set_opt(sb, NO_UID32);
4036         /* xattr user namespace & acls are now defaulted on */
4037         set_opt(sb, XATTR_USER);
4038 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4039         set_opt(sb, POSIX_ACL);
4040 #endif
4041         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4042         if (ext4_has_metadata_csum(sb))
4043                 set_opt(sb, JOURNAL_CHECKSUM);
4044
4045         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4046                 set_opt(sb, JOURNAL_DATA);
4047         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4048                 set_opt(sb, ORDERED_DATA);
4049         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4050                 set_opt(sb, WRITEBACK_DATA);
4051
4052         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
4053                 set_opt(sb, ERRORS_PANIC);
4054         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
4055                 set_opt(sb, ERRORS_CONT);
4056         else
4057                 set_opt(sb, ERRORS_RO);
4058         /* block_validity enabled by default; disable with noblock_validity */
4059         set_opt(sb, BLOCK_VALIDITY);
4060         if (def_mount_opts & EXT4_DEFM_DISCARD)
4061                 set_opt(sb, DISCARD);
4062
4063         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
4064         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
4065         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
4066         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
4067         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
4068
4069         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4070                 set_opt(sb, BARRIER);
4071
4072         /*
4073          * enable delayed allocation by default
4074          * Use -o nodelalloc to turn it off
4075          */
4076         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4077             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4078                 set_opt(sb, DELALLOC);
4079
4080         /*
4081          * set default s_li_wait_mult for lazyinit, for the case there is
4082          * no mount option specified.
4083          */
4084         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
4085
4086         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
4087
4088         if (blocksize == PAGE_SIZE)
4089                 set_opt(sb, DIOREAD_NOLOCK);
4090
4091         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
4092             blocksize > EXT4_MAX_BLOCK_SIZE) {
4093                 ext4_msg(sb, KERN_ERR,
4094                        "Unsupported filesystem blocksize %d (%d log_block_size)",
4095                          blocksize, le32_to_cpu(es->s_log_block_size));
4096                 goto failed_mount;
4097         }
4098
4099         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4100                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4101                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4102         } else {
4103                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4104                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4105                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4106                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4107                                  sbi->s_first_ino);
4108                         goto failed_mount;
4109                 }
4110                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4111                     (!is_power_of_2(sbi->s_inode_size)) ||
4112                     (sbi->s_inode_size > blocksize)) {
4113                         ext4_msg(sb, KERN_ERR,
4114                                "unsupported inode size: %d",
4115                                sbi->s_inode_size);
4116                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
4117                         goto failed_mount;
4118                 }
4119                 /*
4120                  * i_atime_extra is the last extra field available for
4121                  * [acm]times in struct ext4_inode. Checking for that
4122                  * field should suffice to ensure we have extra space
4123                  * for all three.
4124                  */
4125                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4126                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4127                         sb->s_time_gran = 1;
4128                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4129                 } else {
4130                         sb->s_time_gran = NSEC_PER_SEC;
4131                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4132                 }
4133                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4134         }
4135         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4136                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4137                         EXT4_GOOD_OLD_INODE_SIZE;
4138                 if (ext4_has_feature_extra_isize(sb)) {
4139                         unsigned v, max = (sbi->s_inode_size -
4140                                            EXT4_GOOD_OLD_INODE_SIZE);
4141
4142                         v = le16_to_cpu(es->s_want_extra_isize);
4143                         if (v > max) {
4144                                 ext4_msg(sb, KERN_ERR,
4145                                          "bad s_want_extra_isize: %d", v);
4146                                 goto failed_mount;
4147                         }
4148                         if (sbi->s_want_extra_isize < v)
4149                                 sbi->s_want_extra_isize = v;
4150
4151                         v = le16_to_cpu(es->s_min_extra_isize);
4152                         if (v > max) {
4153                                 ext4_msg(sb, KERN_ERR,
4154                                          "bad s_min_extra_isize: %d", v);
4155                                 goto failed_mount;
4156                         }
4157                         if (sbi->s_want_extra_isize < v)
4158                                 sbi->s_want_extra_isize = v;
4159                 }
4160         }
4161
4162         if (sbi->s_es->s_mount_opts[0]) {
4163                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
4164                                               sizeof(sbi->s_es->s_mount_opts),
4165                                               GFP_KERNEL);
4166                 if (!s_mount_opts)
4167                         goto failed_mount;
4168                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
4169                                    &journal_ioprio, 0)) {
4170                         ext4_msg(sb, KERN_WARNING,
4171                                  "failed to parse options in superblock: %s",
4172                                  s_mount_opts);
4173                 }
4174                 kfree(s_mount_opts);
4175         }
4176         sbi->s_def_mount_opt = sbi->s_mount_opt;
4177         if (!parse_options((char *) data, sb, &journal_devnum,
4178                            &journal_ioprio, 0))
4179                 goto failed_mount;
4180
4181 #ifdef CONFIG_UNICODE
4182         if (ext4_has_feature_casefold(sb) && !sbi->s_encoding) {
4183                 const struct ext4_sb_encodings *encoding_info;
4184                 struct unicode_map *encoding;
4185                 __u16 encoding_flags;
4186
4187                 if (ext4_has_feature_encrypt(sb)) {
4188                         ext4_msg(sb, KERN_ERR,
4189                                  "Can't mount with encoding and encryption");
4190                         goto failed_mount;
4191                 }
4192
4193                 if (ext4_sb_read_encoding(es, &encoding_info,
4194                                           &encoding_flags)) {
4195                         ext4_msg(sb, KERN_ERR,
4196                                  "Encoding requested by superblock is unknown");
4197                         goto failed_mount;
4198                 }
4199
4200                 encoding = utf8_load(encoding_info->version);
4201                 if (IS_ERR(encoding)) {
4202                         ext4_msg(sb, KERN_ERR,
4203                                  "can't mount with superblock charset: %s-%s "
4204                                  "not supported by the kernel. flags: 0x%x.",
4205                                  encoding_info->name, encoding_info->version,
4206                                  encoding_flags);
4207                         goto failed_mount;
4208                 }
4209                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4210                          "%s-%s with flags 0x%hx", encoding_info->name,
4211                          encoding_info->version?:"\b", encoding_flags);
4212
4213                 sbi->s_encoding = encoding;
4214                 sbi->s_encoding_flags = encoding_flags;
4215         }
4216 #endif
4217
4218         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4219                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, and O_DIRECT support!\n");
4220                 /* can't mount with both data=journal and dioread_nolock. */
4221                 clear_opt(sb, DIOREAD_NOLOCK);
4222                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4223                         ext4_msg(sb, KERN_ERR, "can't mount with "
4224                                  "both data=journal and delalloc");
4225                         goto failed_mount;
4226                 }
4227                 if (test_opt(sb, DAX_ALWAYS)) {
4228                         ext4_msg(sb, KERN_ERR, "can't mount with "
4229                                  "both data=journal and dax");
4230                         goto failed_mount;
4231                 }
4232                 if (ext4_has_feature_encrypt(sb)) {
4233                         ext4_msg(sb, KERN_WARNING,
4234                                  "encrypted files will use data=ordered "
4235                                  "instead of data journaling mode");
4236                 }
4237                 if (test_opt(sb, DELALLOC))
4238                         clear_opt(sb, DELALLOC);
4239         } else {
4240                 sb->s_iflags |= SB_I_CGROUPWB;
4241         }
4242
4243         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4244                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4245
4246         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4247             (ext4_has_compat_features(sb) ||
4248              ext4_has_ro_compat_features(sb) ||
4249              ext4_has_incompat_features(sb)))
4250                 ext4_msg(sb, KERN_WARNING,
4251                        "feature flags set on rev 0 fs, "
4252                        "running e2fsck is recommended");
4253
4254         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4255                 set_opt2(sb, HURD_COMPAT);
4256                 if (ext4_has_feature_64bit(sb)) {
4257                         ext4_msg(sb, KERN_ERR,
4258                                  "The Hurd can't support 64-bit file systems");
4259                         goto failed_mount;
4260                 }
4261
4262                 /*
4263                  * ea_inode feature uses l_i_version field which is not
4264                  * available in HURD_COMPAT mode.
4265                  */
4266                 if (ext4_has_feature_ea_inode(sb)) {
4267                         ext4_msg(sb, KERN_ERR,
4268                                  "ea_inode feature is not supported for Hurd");
4269                         goto failed_mount;
4270                 }
4271         }
4272
4273         if (IS_EXT2_SB(sb)) {
4274                 if (ext2_feature_set_ok(sb))
4275                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4276                                  "using the ext4 subsystem");
4277                 else {
4278                         /*
4279                          * If we're probing be silent, if this looks like
4280                          * it's actually an ext[34] filesystem.
4281                          */
4282                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4283                                 goto failed_mount;
4284                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4285                                  "to feature incompatibilities");
4286                         goto failed_mount;
4287                 }
4288         }
4289
4290         if (IS_EXT3_SB(sb)) {
4291                 if (ext3_feature_set_ok(sb))
4292                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4293                                  "using the ext4 subsystem");
4294                 else {
4295                         /*
4296                          * If we're probing be silent, if this looks like
4297                          * it's actually an ext4 filesystem.
4298                          */
4299                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4300                                 goto failed_mount;
4301                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4302                                  "to feature incompatibilities");
4303                         goto failed_mount;
4304                 }
4305         }
4306
4307         /*
4308          * Check feature flags regardless of the revision level, since we
4309          * previously didn't change the revision level when setting the flags,
4310          * so there is a chance incompat flags are set on a rev 0 filesystem.
4311          */
4312         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4313                 goto failed_mount;
4314
4315         if (le32_to_cpu(es->s_log_block_size) >
4316             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4317                 ext4_msg(sb, KERN_ERR,
4318                          "Invalid log block size: %u",
4319                          le32_to_cpu(es->s_log_block_size));
4320                 goto failed_mount;
4321         }
4322         if (le32_to_cpu(es->s_log_cluster_size) >
4323             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4324                 ext4_msg(sb, KERN_ERR,
4325                          "Invalid log cluster size: %u",
4326                          le32_to_cpu(es->s_log_cluster_size));
4327                 goto failed_mount;
4328         }
4329
4330         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4331                 ext4_msg(sb, KERN_ERR,
4332                          "Number of reserved GDT blocks insanely large: %d",
4333                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4334                 goto failed_mount;
4335         }
4336
4337         if (bdev_dax_supported(sb->s_bdev, blocksize))
4338                 set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4339
4340         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4341                 if (ext4_has_feature_inline_data(sb)) {
4342                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4343                                         " that may contain inline data");
4344                         goto failed_mount;
4345                 }
4346                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4347                         ext4_msg(sb, KERN_ERR,
4348                                 "DAX unsupported by block device.");
4349                         goto failed_mount;
4350                 }
4351         }
4352
4353         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4354                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4355                          es->s_encryption_level);
4356                 goto failed_mount;
4357         }
4358
4359         if (sb->s_blocksize != blocksize) {
4360                 /* Validate the filesystem blocksize */
4361                 if (!sb_set_blocksize(sb, blocksize)) {
4362                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4363                                         blocksize);
4364                         goto failed_mount;
4365                 }
4366
4367                 brelse(bh);
4368                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4369                 offset = do_div(logical_sb_block, blocksize);
4370                 bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4371                 if (IS_ERR(bh)) {
4372                         ext4_msg(sb, KERN_ERR,
4373                                "Can't read superblock on 2nd try");
4374                         ret = PTR_ERR(bh);
4375                         bh = NULL;
4376                         goto failed_mount;
4377                 }
4378                 es = (struct ext4_super_block *)(bh->b_data + offset);
4379                 sbi->s_es = es;
4380                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4381                         ext4_msg(sb, KERN_ERR,
4382                                "Magic mismatch, very weird!");
4383                         goto failed_mount;
4384                 }
4385         }
4386
4387         has_huge_files = ext4_has_feature_huge_file(sb);
4388         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4389                                                       has_huge_files);
4390         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4391
4392         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4393         if (ext4_has_feature_64bit(sb)) {
4394                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4395                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4396                     !is_power_of_2(sbi->s_desc_size)) {
4397                         ext4_msg(sb, KERN_ERR,
4398                                "unsupported descriptor size %lu",
4399                                sbi->s_desc_size);
4400                         goto failed_mount;
4401                 }
4402         } else
4403                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4404
4405         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4406         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4407
4408         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4409         if (sbi->s_inodes_per_block == 0)
4410                 goto cantfind_ext4;
4411         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4412             sbi->s_inodes_per_group > blocksize * 8) {
4413                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4414                          sbi->s_inodes_per_group);
4415                 goto failed_mount;
4416         }
4417         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4418                                         sbi->s_inodes_per_block;
4419         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4420         sbi->s_sbh = bh;
4421         sbi->s_mount_state = le16_to_cpu(es->s_state);
4422         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4423         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4424
4425         for (i = 0; i < 4; i++)
4426                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4427         sbi->s_def_hash_version = es->s_def_hash_version;
4428         if (ext4_has_feature_dir_index(sb)) {
4429                 i = le32_to_cpu(es->s_flags);
4430                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4431                         sbi->s_hash_unsigned = 3;
4432                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4433 #ifdef __CHAR_UNSIGNED__
4434                         if (!sb_rdonly(sb))
4435                                 es->s_flags |=
4436                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4437                         sbi->s_hash_unsigned = 3;
4438 #else
4439                         if (!sb_rdonly(sb))
4440                                 es->s_flags |=
4441                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4442 #endif
4443                 }
4444         }
4445
4446         /* Handle clustersize */
4447         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4448         if (ext4_has_feature_bigalloc(sb)) {
4449                 if (clustersize < blocksize) {
4450                         ext4_msg(sb, KERN_ERR,
4451                                  "cluster size (%d) smaller than "
4452                                  "block size (%d)", clustersize, blocksize);
4453                         goto failed_mount;
4454                 }
4455                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4456                         le32_to_cpu(es->s_log_block_size);
4457                 sbi->s_clusters_per_group =
4458                         le32_to_cpu(es->s_clusters_per_group);
4459                 if (sbi->s_clusters_per_group > blocksize * 8) {
4460                         ext4_msg(sb, KERN_ERR,
4461                                  "#clusters per group too big: %lu",
4462                                  sbi->s_clusters_per_group);
4463                         goto failed_mount;
4464                 }
4465                 if (sbi->s_blocks_per_group !=
4466                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4467                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4468                                  "clusters per group (%lu) inconsistent",
4469                                  sbi->s_blocks_per_group,
4470                                  sbi->s_clusters_per_group);
4471                         goto failed_mount;
4472                 }
4473         } else {
4474                 if (clustersize != blocksize) {
4475                         ext4_msg(sb, KERN_ERR,
4476                                  "fragment/cluster size (%d) != "
4477                                  "block size (%d)", clustersize, blocksize);
4478                         goto failed_mount;
4479                 }
4480                 if (sbi->s_blocks_per_group > blocksize * 8) {
4481                         ext4_msg(sb, KERN_ERR,
4482                                  "#blocks per group too big: %lu",
4483                                  sbi->s_blocks_per_group);
4484                         goto failed_mount;
4485                 }
4486                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4487                 sbi->s_cluster_bits = 0;
4488         }
4489         sbi->s_cluster_ratio = clustersize / blocksize;
4490
4491         /* Do we have standard group size of clustersize * 8 blocks ? */
4492         if (sbi->s_blocks_per_group == clustersize << 3)
4493                 set_opt2(sb, STD_GROUP_SIZE);
4494
4495         /*
4496          * Test whether we have more sectors than will fit in sector_t,
4497          * and whether the max offset is addressable by the page cache.
4498          */
4499         err = generic_check_addressable(sb->s_blocksize_bits,
4500                                         ext4_blocks_count(es));
4501         if (err) {
4502                 ext4_msg(sb, KERN_ERR, "filesystem"
4503                          " too large to mount safely on this system");
4504                 goto failed_mount;
4505         }
4506
4507         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4508                 goto cantfind_ext4;
4509
4510         /* check blocks count against device size */
4511         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4512         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4513                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4514                        "exceeds size of device (%llu blocks)",
4515                        ext4_blocks_count(es), blocks_count);
4516                 goto failed_mount;
4517         }
4518
4519         /*
4520          * It makes no sense for the first data block to be beyond the end
4521          * of the filesystem.
4522          */
4523         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4524                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4525                          "block %u is beyond end of filesystem (%llu)",
4526                          le32_to_cpu(es->s_first_data_block),
4527                          ext4_blocks_count(es));
4528                 goto failed_mount;
4529         }
4530         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4531             (sbi->s_cluster_ratio == 1)) {
4532                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4533                          "block is 0 with a 1k block and cluster size");
4534                 goto failed_mount;
4535         }
4536
4537         blocks_count = (ext4_blocks_count(es) -
4538                         le32_to_cpu(es->s_first_data_block) +
4539                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4540         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4541         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4542                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4543                        "(block count %llu, first data block %u, "
4544                        "blocks per group %lu)", blocks_count,
4545                        ext4_blocks_count(es),
4546                        le32_to_cpu(es->s_first_data_block),
4547                        EXT4_BLOCKS_PER_GROUP(sb));
4548                 goto failed_mount;
4549         }
4550         sbi->s_groups_count = blocks_count;
4551         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4552                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4553         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4554             le32_to_cpu(es->s_inodes_count)) {
4555                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4556                          le32_to_cpu(es->s_inodes_count),
4557                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4558                 ret = -EINVAL;
4559                 goto failed_mount;
4560         }
4561         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4562                    EXT4_DESC_PER_BLOCK(sb);
4563         if (ext4_has_feature_meta_bg(sb)) {
4564                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4565                         ext4_msg(sb, KERN_WARNING,
4566                                  "first meta block group too large: %u "
4567                                  "(group descriptor block count %u)",
4568                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4569                         goto failed_mount;
4570                 }
4571         }
4572         rcu_assign_pointer(sbi->s_group_desc,
4573                            kvmalloc_array(db_count,
4574                                           sizeof(struct buffer_head *),
4575                                           GFP_KERNEL));
4576         if (sbi->s_group_desc == NULL) {
4577                 ext4_msg(sb, KERN_ERR, "not enough memory");
4578                 ret = -ENOMEM;
4579                 goto failed_mount;
4580         }
4581
4582         bgl_lock_init(sbi->s_blockgroup_lock);
4583
4584         /* Pre-read the descriptors into the buffer cache */
4585         for (i = 0; i < db_count; i++) {
4586                 block = descriptor_loc(sb, logical_sb_block, i);
4587                 ext4_sb_breadahead_unmovable(sb, block);
4588         }
4589
4590         for (i = 0; i < db_count; i++) {
4591                 struct buffer_head *bh;
4592
4593                 block = descriptor_loc(sb, logical_sb_block, i);
4594                 bh = ext4_sb_bread_unmovable(sb, block);
4595                 if (IS_ERR(bh)) {
4596                         ext4_msg(sb, KERN_ERR,
4597                                "can't read group descriptor %d", i);
4598                         db_count = i;
4599                         ret = PTR_ERR(bh);
4600                         bh = NULL;
4601                         goto failed_mount2;
4602                 }
4603                 rcu_read_lock();
4604                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4605                 rcu_read_unlock();
4606         }
4607         sbi->s_gdb_count = db_count;
4608         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4609                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4610                 ret = -EFSCORRUPTED;
4611                 goto failed_mount2;
4612         }
4613
4614         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4615
4616         /* Register extent status tree shrinker */
4617         if (ext4_es_register_shrinker(sbi))
4618                 goto failed_mount3;
4619
4620         sbi->s_stripe = ext4_get_stripe_size(sbi);
4621         sbi->s_extent_max_zeroout_kb = 32;
4622
4623         /*
4624          * set up enough so that it can read an inode
4625          */
4626         sb->s_op = &ext4_sops;
4627         sb->s_export_op = &ext4_export_ops;
4628         sb->s_xattr = ext4_xattr_handlers;
4629 #ifdef CONFIG_FS_ENCRYPTION
4630         sb->s_cop = &ext4_cryptops;
4631 #endif
4632 #ifdef CONFIG_FS_VERITY
4633         sb->s_vop = &ext4_verityops;
4634 #endif
4635 #ifdef CONFIG_QUOTA
4636         sb->dq_op = &ext4_quota_operations;
4637         if (ext4_has_feature_quota(sb))
4638                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4639         else
4640                 sb->s_qcop = &ext4_qctl_operations;
4641         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4642 #endif
4643         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4644
4645         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4646         mutex_init(&sbi->s_orphan_lock);
4647
4648         sb->s_root = NULL;
4649
4650         needs_recovery = (es->s_last_orphan != 0 ||
4651                           ext4_has_feature_journal_needs_recovery(sb));
4652
4653         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4654                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4655                         goto failed_mount3a;
4656
4657         /*
4658          * The first inode we look at is the journal inode.  Don't try
4659          * root first: it may be modified in the journal!
4660          */
4661         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4662                 err = ext4_load_journal(sb, es, journal_devnum);
4663                 if (err)
4664                         goto failed_mount3a;
4665         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4666                    ext4_has_feature_journal_needs_recovery(sb)) {
4667                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4668                        "suppressed and not mounted read-only");
4669                 goto failed_mount_wq;
4670         } else {
4671                 /* Nojournal mode, all journal mount options are illegal */
4672                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4673                         ext4_msg(sb, KERN_ERR, "can't mount with "
4674                                  "journal_checksum, fs mounted w/o journal");
4675                         goto failed_mount_wq;
4676                 }
4677                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4678                         ext4_msg(sb, KERN_ERR, "can't mount with "
4679                                  "journal_async_commit, fs mounted w/o journal");
4680                         goto failed_mount_wq;
4681                 }
4682                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4683                         ext4_msg(sb, KERN_ERR, "can't mount with "
4684                                  "commit=%lu, fs mounted w/o journal",
4685                                  sbi->s_commit_interval / HZ);
4686                         goto failed_mount_wq;
4687                 }
4688                 if (EXT4_MOUNT_DATA_FLAGS &
4689                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4690                         ext4_msg(sb, KERN_ERR, "can't mount with "
4691                                  "data=, fs mounted w/o journal");
4692                         goto failed_mount_wq;
4693                 }
4694                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4695                 clear_opt(sb, JOURNAL_CHECKSUM);
4696                 clear_opt(sb, DATA_FLAGS);
4697                 sbi->s_journal = NULL;
4698                 needs_recovery = 0;
4699                 goto no_journal;
4700         }
4701
4702         if (ext4_has_feature_64bit(sb) &&
4703             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4704                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4705                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4706                 goto failed_mount_wq;
4707         }
4708
4709         if (!set_journal_csum_feature_set(sb)) {
4710                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4711                          "feature set");
4712                 goto failed_mount_wq;
4713         }
4714
4715         /* We have now updated the journal if required, so we can
4716          * validate the data journaling mode. */
4717         switch (test_opt(sb, DATA_FLAGS)) {
4718         case 0:
4719                 /* No mode set, assume a default based on the journal
4720                  * capabilities: ORDERED_DATA if the journal can
4721                  * cope, else JOURNAL_DATA
4722                  */
4723                 if (jbd2_journal_check_available_features
4724                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4725                         set_opt(sb, ORDERED_DATA);
4726                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4727                 } else {
4728                         set_opt(sb, JOURNAL_DATA);
4729                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4730                 }
4731                 break;
4732
4733         case EXT4_MOUNT_ORDERED_DATA:
4734         case EXT4_MOUNT_WRITEBACK_DATA:
4735                 if (!jbd2_journal_check_available_features
4736                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4737                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4738                                "requested data journaling mode");
4739                         goto failed_mount_wq;
4740                 }
4741         default:
4742                 break;
4743         }
4744
4745         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4746             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4747                 ext4_msg(sb, KERN_ERR, "can't mount with "
4748                         "journal_async_commit in data=ordered mode");
4749                 goto failed_mount_wq;
4750         }
4751
4752         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4753
4754         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4755         sbi->s_journal->j_submit_inode_data_buffers =
4756                 jbd2_journal_submit_inode_data_buffers;
4757         sbi->s_journal->j_finish_inode_data_buffers =
4758                 jbd2_journal_finish_inode_data_buffers;
4759
4760 no_journal:
4761         if (!test_opt(sb, NO_MBCACHE)) {
4762                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4763                 if (!sbi->s_ea_block_cache) {
4764                         ext4_msg(sb, KERN_ERR,
4765                                  "Failed to create ea_block_cache");
4766                         goto failed_mount_wq;
4767                 }
4768
4769                 if (ext4_has_feature_ea_inode(sb)) {
4770                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4771                         if (!sbi->s_ea_inode_cache) {
4772                                 ext4_msg(sb, KERN_ERR,
4773                                          "Failed to create ea_inode_cache");
4774                                 goto failed_mount_wq;
4775                         }
4776                 }
4777         }
4778
4779         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4780                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4781                 goto failed_mount_wq;
4782         }
4783
4784         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4785             !ext4_has_feature_encrypt(sb)) {
4786                 ext4_set_feature_encrypt(sb);
4787                 ext4_commit_super(sb, 1);
4788         }
4789
4790         /*
4791          * Get the # of file system overhead blocks from the
4792          * superblock if present.
4793          */
4794         if (es->s_overhead_clusters)
4795                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4796         else {
4797                 err = ext4_calculate_overhead(sb);
4798                 if (err)
4799                         goto failed_mount_wq;
4800         }
4801
4802         /*
4803          * The maximum number of concurrent works can be high and
4804          * concurrency isn't really necessary.  Limit it to 1.
4805          */
4806         EXT4_SB(sb)->rsv_conversion_wq =
4807                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4808         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4809                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4810                 ret = -ENOMEM;
4811                 goto failed_mount4;
4812         }
4813
4814         /*
4815          * The jbd2_journal_load will have done any necessary log recovery,
4816          * so we can safely mount the rest of the filesystem now.
4817          */
4818
4819         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4820         if (IS_ERR(root)) {
4821                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4822                 ret = PTR_ERR(root);
4823                 root = NULL;
4824                 goto failed_mount4;
4825         }
4826         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4827                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4828                 iput(root);
4829                 goto failed_mount4;
4830         }
4831
4832 #ifdef CONFIG_UNICODE
4833         if (sbi->s_encoding)
4834                 sb->s_d_op = &ext4_dentry_ops;
4835 #endif
4836
4837         sb->s_root = d_make_root(root);
4838         if (!sb->s_root) {
4839                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4840                 ret = -ENOMEM;
4841                 goto failed_mount4;
4842         }
4843
4844         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4845         if (ret == -EROFS) {
4846                 sb->s_flags |= SB_RDONLY;
4847                 ret = 0;
4848         } else if (ret)
4849                 goto failed_mount4a;
4850
4851         ext4_set_resv_clusters(sb);
4852
4853         if (test_opt(sb, BLOCK_VALIDITY)) {
4854                 err = ext4_setup_system_zone(sb);
4855                 if (err) {
4856                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
4857                                  "zone (%d)", err);
4858                         goto failed_mount4a;
4859                 }
4860         }
4861
4862         ext4_ext_init(sb);
4863         err = ext4_mb_init(sb);
4864         if (err) {
4865                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4866                          err);
4867                 goto failed_mount5;
4868         }
4869
4870         block = ext4_count_free_clusters(sb);
4871         ext4_free_blocks_count_set(sbi->s_es,
4872                                    EXT4_C2B(sbi, block));
4873         ext4_superblock_csum_set(sb);
4874         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4875                                   GFP_KERNEL);
4876         if (!err) {
4877                 unsigned long freei = ext4_count_free_inodes(sb);
4878                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4879                 ext4_superblock_csum_set(sb);
4880                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4881                                           GFP_KERNEL);
4882         }
4883         if (!err)
4884                 err = percpu_counter_init(&sbi->s_dirs_counter,
4885                                           ext4_count_dirs(sb), GFP_KERNEL);
4886         if (!err)
4887                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4888                                           GFP_KERNEL);
4889         if (!err)
4890                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
4891
4892         if (err) {
4893                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4894                 goto failed_mount6;
4895         }
4896
4897         if (ext4_has_feature_flex_bg(sb))
4898                 if (!ext4_fill_flex_info(sb)) {
4899                         ext4_msg(sb, KERN_ERR,
4900                                "unable to initialize "
4901                                "flex_bg meta info!");
4902                         goto failed_mount6;
4903                 }
4904
4905         err = ext4_register_li_request(sb, first_not_zeroed);
4906         if (err)
4907                 goto failed_mount6;
4908
4909         err = ext4_register_sysfs(sb);
4910         if (err)
4911                 goto failed_mount7;
4912
4913 #ifdef CONFIG_QUOTA
4914         /* Enable quota usage during mount. */
4915         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4916                 err = ext4_enable_quotas(sb);
4917                 if (err)
4918                         goto failed_mount8;
4919         }
4920 #endif  /* CONFIG_QUOTA */
4921
4922         /*
4923          * Save the original bdev mapping's wb_err value which could be
4924          * used to detect the metadata async write error.
4925          */
4926         spin_lock_init(&sbi->s_bdev_wb_lock);
4927         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
4928                                  &sbi->s_bdev_wb_err);
4929         sb->s_bdev->bd_super = sb;
4930         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4931         ext4_orphan_cleanup(sb, es);
4932         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4933         if (needs_recovery) {
4934                 ext4_msg(sb, KERN_INFO, "recovery complete");
4935                 err = ext4_mark_recovery_complete(sb, es);
4936                 if (err)
4937                         goto failed_mount8;
4938         }
4939         if (EXT4_SB(sb)->s_journal) {
4940                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4941                         descr = " journalled data mode";
4942                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4943                         descr = " ordered data mode";
4944                 else
4945                         descr = " writeback data mode";
4946         } else
4947                 descr = "out journal";
4948
4949         if (test_opt(sb, DISCARD)) {
4950                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4951                 if (!blk_queue_discard(q))
4952                         ext4_msg(sb, KERN_WARNING,
4953                                  "mounting with \"discard\" option, but "
4954                                  "the device does not support discard");
4955         }
4956
4957         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4958                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4959                          "Opts: %.*s%s%s", descr,
4960                          (int) sizeof(sbi->s_es->s_mount_opts),
4961                          sbi->s_es->s_mount_opts,
4962                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4963
4964         if (es->s_error_count)
4965                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4966
4967         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4968         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4969         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4970         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4971         atomic_set(&sbi->s_warning_count, 0);
4972         atomic_set(&sbi->s_msg_count, 0);
4973
4974         kfree(orig_data);
4975         return 0;
4976
4977 cantfind_ext4:
4978         if (!silent)
4979                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4980         goto failed_mount;
4981
4982 failed_mount8:
4983         ext4_unregister_sysfs(sb);
4984         kobject_put(&sbi->s_kobj);
4985 failed_mount7:
4986         ext4_unregister_li_request(sb);
4987 failed_mount6:
4988         ext4_mb_release(sb);
4989         rcu_read_lock();
4990         flex_groups = rcu_dereference(sbi->s_flex_groups);
4991         if (flex_groups) {
4992                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
4993                         kvfree(flex_groups[i]);
4994                 kvfree(flex_groups);
4995         }
4996         rcu_read_unlock();
4997         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4998         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4999         percpu_counter_destroy(&sbi->s_dirs_counter);
5000         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
5001         percpu_free_rwsem(&sbi->s_writepages_rwsem);
5002 failed_mount5:
5003         ext4_ext_release(sb);
5004         ext4_release_system_zone(sb);
5005 failed_mount4a:
5006         dput(sb->s_root);
5007         sb->s_root = NULL;
5008 failed_mount4:
5009         ext4_msg(sb, KERN_ERR, "mount failed");
5010         if (EXT4_SB(sb)->rsv_conversion_wq)
5011                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5012 failed_mount_wq:
5013         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5014         sbi->s_ea_inode_cache = NULL;
5015
5016         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5017         sbi->s_ea_block_cache = NULL;
5018
5019         if (sbi->s_journal) {
5020                 jbd2_journal_destroy(sbi->s_journal);
5021                 sbi->s_journal = NULL;
5022         }
5023 failed_mount3a:
5024         ext4_es_unregister_shrinker(sbi);
5025 failed_mount3:
5026         del_timer_sync(&sbi->s_err_report);
5027         if (sbi->s_mmp_tsk)
5028                 kthread_stop(sbi->s_mmp_tsk);
5029 failed_mount2:
5030         rcu_read_lock();
5031         group_desc = rcu_dereference(sbi->s_group_desc);
5032         for (i = 0; i < db_count; i++)
5033                 brelse(group_desc[i]);
5034         kvfree(group_desc);
5035         rcu_read_unlock();
5036 failed_mount:
5037         if (sbi->s_chksum_driver)
5038                 crypto_free_shash(sbi->s_chksum_driver);
5039
5040 #ifdef CONFIG_UNICODE
5041         utf8_unload(sbi->s_encoding);
5042 #endif
5043
5044 #ifdef CONFIG_QUOTA
5045         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5046                 kfree(get_qf_name(sb, sbi, i));
5047 #endif
5048         fscrypt_free_dummy_context(&sbi->s_dummy_enc_ctx);
5049         ext4_blkdev_remove(sbi);
5050         brelse(bh);
5051 out_fail:
5052         sb->s_fs_info = NULL;
5053         kfree(sbi->s_blockgroup_lock);
5054 out_free_base:
5055         kfree(sbi);
5056         kfree(orig_data);
5057         fs_put_dax(dax_dev);
5058         return err ? err : ret;
5059 }
5060
5061 /*
5062  * Setup any per-fs journal parameters now.  We'll do this both on
5063  * initial mount, once the journal has been initialised but before we've
5064  * done any recovery; and again on any subsequent remount.
5065  */
5066 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5067 {
5068         struct ext4_sb_info *sbi = EXT4_SB(sb);
5069
5070         journal->j_commit_interval = sbi->s_commit_interval;
5071         journal->j_min_batch_time = sbi->s_min_batch_time;
5072         journal->j_max_batch_time = sbi->s_max_batch_time;
5073
5074         write_lock(&journal->j_state_lock);
5075         if (test_opt(sb, BARRIER))
5076                 journal->j_flags |= JBD2_BARRIER;
5077         else
5078                 journal->j_flags &= ~JBD2_BARRIER;
5079         if (test_opt(sb, DATA_ERR_ABORT))
5080                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5081         else
5082                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5083         write_unlock(&journal->j_state_lock);
5084 }
5085
5086 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5087                                              unsigned int journal_inum)
5088 {
5089         struct inode *journal_inode;
5090
5091         /*
5092          * Test for the existence of a valid inode on disk.  Bad things
5093          * happen if we iget() an unused inode, as the subsequent iput()
5094          * will try to delete it.
5095          */
5096         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5097         if (IS_ERR(journal_inode)) {
5098                 ext4_msg(sb, KERN_ERR, "no journal found");
5099                 return NULL;
5100         }
5101         if (!journal_inode->i_nlink) {
5102                 make_bad_inode(journal_inode);
5103                 iput(journal_inode);
5104                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5105                 return NULL;
5106         }
5107
5108         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
5109                   journal_inode, journal_inode->i_size);
5110         if (!S_ISREG(journal_inode->i_mode)) {
5111                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5112                 iput(journal_inode);
5113                 return NULL;
5114         }
5115         return journal_inode;
5116 }
5117
5118 static journal_t *ext4_get_journal(struct super_block *sb,
5119                                    unsigned int journal_inum)
5120 {
5121         struct inode *journal_inode;
5122         journal_t *journal;
5123
5124         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5125                 return NULL;
5126
5127         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5128         if (!journal_inode)
5129                 return NULL;
5130
5131         journal = jbd2_journal_init_inode(journal_inode);
5132         if (!journal) {
5133                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5134                 iput(journal_inode);
5135                 return NULL;
5136         }
5137         journal->j_private = sb;
5138         ext4_init_journal_params(sb, journal);
5139         return journal;
5140 }
5141
5142 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5143                                        dev_t j_dev)
5144 {
5145         struct buffer_head *bh;
5146         journal_t *journal;
5147         ext4_fsblk_t start;
5148         ext4_fsblk_t len;
5149         int hblock, blocksize;
5150         ext4_fsblk_t sb_block;
5151         unsigned long offset;
5152         struct ext4_super_block *es;
5153         struct block_device *bdev;
5154
5155         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5156                 return NULL;
5157
5158         bdev = ext4_blkdev_get(j_dev, sb);
5159         if (bdev == NULL)
5160                 return NULL;
5161
5162         blocksize = sb->s_blocksize;
5163         hblock = bdev_logical_block_size(bdev);
5164         if (blocksize < hblock) {
5165                 ext4_msg(sb, KERN_ERR,
5166                         "blocksize too small for journal device");
5167                 goto out_bdev;
5168         }
5169
5170         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5171         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5172         set_blocksize(bdev, blocksize);
5173         if (!(bh = __bread(bdev, sb_block, blocksize))) {
5174                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5175                        "external journal");
5176                 goto out_bdev;
5177         }
5178
5179         es = (struct ext4_super_block *) (bh->b_data + offset);
5180         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5181             !(le32_to_cpu(es->s_feature_incompat) &
5182               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5183                 ext4_msg(sb, KERN_ERR, "external journal has "
5184                                         "bad superblock");
5185                 brelse(bh);
5186                 goto out_bdev;
5187         }
5188
5189         if ((le32_to_cpu(es->s_feature_ro_compat) &
5190              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5191             es->s_checksum != ext4_superblock_csum(sb, es)) {
5192                 ext4_msg(sb, KERN_ERR, "external journal has "
5193                                        "corrupt superblock");
5194                 brelse(bh);
5195                 goto out_bdev;
5196         }
5197
5198         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5199                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5200                 brelse(bh);
5201                 goto out_bdev;
5202         }
5203
5204         len = ext4_blocks_count(es);
5205         start = sb_block + 1;
5206         brelse(bh);     /* we're done with the superblock */
5207
5208         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5209                                         start, len, blocksize);
5210         if (!journal) {
5211                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5212                 goto out_bdev;
5213         }
5214         journal->j_private = sb;
5215         if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
5216                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5217                 goto out_journal;
5218         }
5219         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5220                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5221                                         "user (unsupported) - %d",
5222                         be32_to_cpu(journal->j_superblock->s_nr_users));
5223                 goto out_journal;
5224         }
5225         EXT4_SB(sb)->s_journal_bdev = bdev;
5226         ext4_init_journal_params(sb, journal);
5227         return journal;
5228
5229 out_journal:
5230         jbd2_journal_destroy(journal);
5231 out_bdev:
5232         ext4_blkdev_put(bdev);
5233         return NULL;
5234 }
5235
5236 static int ext4_load_journal(struct super_block *sb,
5237                              struct ext4_super_block *es,
5238                              unsigned long journal_devnum)
5239 {
5240         journal_t *journal;
5241         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5242         dev_t journal_dev;
5243         int err = 0;
5244         int really_read_only;
5245         int journal_dev_ro;
5246
5247         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5248                 return -EFSCORRUPTED;
5249
5250         if (journal_devnum &&
5251             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5252                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5253                         "numbers have changed");
5254                 journal_dev = new_decode_dev(journal_devnum);
5255         } else
5256                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5257
5258         if (journal_inum && journal_dev) {
5259                 ext4_msg(sb, KERN_ERR,
5260                          "filesystem has both journal inode and journal device!");
5261                 return -EINVAL;
5262         }
5263
5264         if (journal_inum) {
5265                 journal = ext4_get_journal(sb, journal_inum);
5266                 if (!journal)
5267                         return -EINVAL;
5268         } else {
5269                 journal = ext4_get_dev_journal(sb, journal_dev);
5270                 if (!journal)
5271                         return -EINVAL;
5272         }
5273
5274         journal_dev_ro = bdev_read_only(journal->j_dev);
5275         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5276
5277         if (journal_dev_ro && !sb_rdonly(sb)) {
5278                 ext4_msg(sb, KERN_ERR,
5279                          "journal device read-only, try mounting with '-o ro'");
5280                 err = -EROFS;
5281                 goto err_out;
5282         }
5283
5284         /*
5285          * Are we loading a blank journal or performing recovery after a
5286          * crash?  For recovery, we need to check in advance whether we
5287          * can get read-write access to the device.
5288          */
5289         if (ext4_has_feature_journal_needs_recovery(sb)) {
5290                 if (sb_rdonly(sb)) {
5291                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5292                                         "required on readonly filesystem");
5293                         if (really_read_only) {
5294                                 ext4_msg(sb, KERN_ERR, "write access "
5295                                         "unavailable, cannot proceed "
5296                                         "(try mounting with noload)");
5297                                 err = -EROFS;
5298                                 goto err_out;
5299                         }
5300                         ext4_msg(sb, KERN_INFO, "write access will "
5301                                "be enabled during recovery");
5302                 }
5303         }
5304
5305         if (!(journal->j_flags & JBD2_BARRIER))
5306                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5307
5308         if (!ext4_has_feature_journal_needs_recovery(sb))
5309                 err = jbd2_journal_wipe(journal, !really_read_only);
5310         if (!err) {
5311                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5312                 if (save)
5313                         memcpy(save, ((char *) es) +
5314                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5315                 err = jbd2_journal_load(journal);
5316                 if (save)
5317                         memcpy(((char *) es) + EXT4_S_ERR_START,
5318                                save, EXT4_S_ERR_LEN);
5319                 kfree(save);
5320         }
5321
5322         if (err) {
5323                 ext4_msg(sb, KERN_ERR, "error loading journal");
5324                 goto err_out;
5325         }
5326
5327         EXT4_SB(sb)->s_journal = journal;
5328         err = ext4_clear_journal_err(sb, es);
5329         if (err) {
5330                 EXT4_SB(sb)->s_journal = NULL;
5331                 jbd2_journal_destroy(journal);
5332                 return err;
5333         }
5334
5335         if (!really_read_only && journal_devnum &&
5336             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5337                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5338
5339                 /* Make sure we flush the recovery flag to disk. */
5340                 ext4_commit_super(sb, 1);
5341         }
5342
5343         return 0;
5344
5345 err_out:
5346         jbd2_journal_destroy(journal);
5347         return err;
5348 }
5349
5350 static int ext4_commit_super(struct super_block *sb, int sync)
5351 {
5352         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
5353         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5354         int error = 0;
5355
5356         if (!sbh || block_device_ejected(sb))
5357                 return error;
5358
5359         /*
5360          * If the file system is mounted read-only, don't update the
5361          * superblock write time.  This avoids updating the superblock
5362          * write time when we are mounting the root file system
5363          * read/only but we need to replay the journal; at that point,
5364          * for people who are east of GMT and who make their clock
5365          * tick in localtime for Windows bug-for-bug compatibility,
5366          * the clock is set in the future, and this will cause e2fsck
5367          * to complain and force a full file system check.
5368          */
5369         if (!(sb->s_flags & SB_RDONLY))
5370                 ext4_update_tstamp(es, s_wtime);
5371         if (sb->s_bdev->bd_part)
5372                 es->s_kbytes_written =
5373                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5374                             ((part_stat_read(sb->s_bdev->bd_part,
5375                                              sectors[STAT_WRITE]) -
5376                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
5377         else
5378                 es->s_kbytes_written =
5379                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5380         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5381                 ext4_free_blocks_count_set(es,
5382                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5383                                 &EXT4_SB(sb)->s_freeclusters_counter)));
5384         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5385                 es->s_free_inodes_count =
5386                         cpu_to_le32(percpu_counter_sum_positive(
5387                                 &EXT4_SB(sb)->s_freeinodes_counter));
5388         BUFFER_TRACE(sbh, "marking dirty");
5389         ext4_superblock_csum_set(sb);
5390         if (sync)
5391                 lock_buffer(sbh);
5392         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5393                 /*
5394                  * Oh, dear.  A previous attempt to write the
5395                  * superblock failed.  This could happen because the
5396                  * USB device was yanked out.  Or it could happen to
5397                  * be a transient write error and maybe the block will
5398                  * be remapped.  Nothing we can do but to retry the
5399                  * write and hope for the best.
5400                  */
5401                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5402                        "superblock detected");
5403                 clear_buffer_write_io_error(sbh);
5404                 set_buffer_uptodate(sbh);
5405         }
5406         mark_buffer_dirty(sbh);
5407         if (sync) {
5408                 unlock_buffer(sbh);
5409                 error = __sync_dirty_buffer(sbh,
5410                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5411                 if (buffer_write_io_error(sbh)) {
5412                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5413                                "superblock");
5414                         clear_buffer_write_io_error(sbh);
5415                         set_buffer_uptodate(sbh);
5416                 }
5417         }
5418         return error;
5419 }
5420
5421 /*
5422  * Have we just finished recovery?  If so, and if we are mounting (or
5423  * remounting) the filesystem readonly, then we will end up with a
5424  * consistent fs on disk.  Record that fact.
5425  */
5426 static int ext4_mark_recovery_complete(struct super_block *sb,
5427                                        struct ext4_super_block *es)
5428 {
5429         int err;
5430         journal_t *journal = EXT4_SB(sb)->s_journal;
5431
5432         if (!ext4_has_feature_journal(sb)) {
5433                 if (journal != NULL) {
5434                         ext4_error(sb, "Journal got removed while the fs was "
5435                                    "mounted!");
5436                         return -EFSCORRUPTED;
5437                 }
5438                 return 0;
5439         }
5440         jbd2_journal_lock_updates(journal);
5441         err = jbd2_journal_flush(journal);
5442         if (err < 0)
5443                 goto out;
5444
5445         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5446                 ext4_clear_feature_journal_needs_recovery(sb);
5447                 ext4_commit_super(sb, 1);
5448         }
5449 out:
5450         jbd2_journal_unlock_updates(journal);
5451         return err;
5452 }
5453
5454 /*
5455  * If we are mounting (or read-write remounting) a filesystem whose journal
5456  * has recorded an error from a previous lifetime, move that error to the
5457  * main filesystem now.
5458  */
5459 static int ext4_clear_journal_err(struct super_block *sb,
5460                                    struct ext4_super_block *es)
5461 {
5462         journal_t *journal;
5463         int j_errno;
5464         const char *errstr;
5465
5466         if (!ext4_has_feature_journal(sb)) {
5467                 ext4_error(sb, "Journal got removed while the fs was mounted!");
5468                 return -EFSCORRUPTED;
5469         }
5470
5471         journal = EXT4_SB(sb)->s_journal;
5472
5473         /*
5474          * Now check for any error status which may have been recorded in the
5475          * journal by a prior ext4_error() or ext4_abort()
5476          */
5477
5478         j_errno = jbd2_journal_errno(journal);
5479         if (j_errno) {
5480                 char nbuf[16];
5481
5482                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5483                 ext4_warning(sb, "Filesystem error recorded "
5484                              "from previous mount: %s", errstr);
5485                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5486
5487                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5488                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5489                 ext4_commit_super(sb, 1);
5490
5491                 jbd2_journal_clear_err(journal);
5492                 jbd2_journal_update_sb_errno(journal);
5493         }
5494         return 0;
5495 }
5496
5497 /*
5498  * Force the running and committing transactions to commit,
5499  * and wait on the commit.
5500  */
5501 int ext4_force_commit(struct super_block *sb)
5502 {
5503         journal_t *journal;
5504
5505         if (sb_rdonly(sb))
5506                 return 0;
5507
5508         journal = EXT4_SB(sb)->s_journal;
5509         return ext4_journal_force_commit(journal);
5510 }
5511
5512 static int ext4_sync_fs(struct super_block *sb, int wait)
5513 {
5514         int ret = 0;
5515         tid_t target;
5516         bool needs_barrier = false;
5517         struct ext4_sb_info *sbi = EXT4_SB(sb);
5518
5519         if (unlikely(ext4_forced_shutdown(sbi)))
5520                 return 0;
5521
5522         trace_ext4_sync_fs(sb, wait);
5523         flush_workqueue(sbi->rsv_conversion_wq);
5524         /*
5525          * Writeback quota in non-journalled quota case - journalled quota has
5526          * no dirty dquots
5527          */
5528         dquot_writeback_dquots(sb, -1);
5529         /*
5530          * Data writeback is possible w/o journal transaction, so barrier must
5531          * being sent at the end of the function. But we can skip it if
5532          * transaction_commit will do it for us.
5533          */
5534         if (sbi->s_journal) {
5535                 target = jbd2_get_latest_transaction(sbi->s_journal);
5536                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5537                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5538                         needs_barrier = true;
5539
5540                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5541                         if (wait)
5542                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5543                                                            target);
5544                 }
5545         } else if (wait && test_opt(sb, BARRIER))
5546                 needs_barrier = true;
5547         if (needs_barrier) {
5548                 int err;
5549                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL);
5550                 if (!ret)
5551                         ret = err;
5552         }
5553
5554         return ret;
5555 }
5556
5557 /*
5558  * LVM calls this function before a (read-only) snapshot is created.  This
5559  * gives us a chance to flush the journal completely and mark the fs clean.
5560  *
5561  * Note that only this function cannot bring a filesystem to be in a clean
5562  * state independently. It relies on upper layer to stop all data & metadata
5563  * modifications.
5564  */
5565 static int ext4_freeze(struct super_block *sb)
5566 {
5567         int error = 0;
5568         journal_t *journal;
5569
5570         if (sb_rdonly(sb))
5571                 return 0;
5572
5573         journal = EXT4_SB(sb)->s_journal;
5574
5575         if (journal) {
5576                 /* Now we set up the journal barrier. */
5577                 jbd2_journal_lock_updates(journal);
5578
5579                 /*
5580                  * Don't clear the needs_recovery flag if we failed to
5581                  * flush the journal.
5582                  */
5583                 error = jbd2_journal_flush(journal);
5584                 if (error < 0)
5585                         goto out;
5586
5587                 /* Journal blocked and flushed, clear needs_recovery flag. */
5588                 ext4_clear_feature_journal_needs_recovery(sb);
5589         }
5590
5591         error = ext4_commit_super(sb, 1);
5592 out:
5593         if (journal)
5594                 /* we rely on upper layer to stop further updates */
5595                 jbd2_journal_unlock_updates(journal);
5596         return error;
5597 }
5598
5599 /*
5600  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5601  * flag here, even though the filesystem is not technically dirty yet.
5602  */
5603 static int ext4_unfreeze(struct super_block *sb)
5604 {
5605         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5606                 return 0;
5607
5608         if (EXT4_SB(sb)->s_journal) {
5609                 /* Reset the needs_recovery flag before the fs is unlocked. */
5610                 ext4_set_feature_journal_needs_recovery(sb);
5611         }
5612
5613         ext4_commit_super(sb, 1);
5614         return 0;
5615 }
5616
5617 /*
5618  * Structure to save mount options for ext4_remount's benefit
5619  */
5620 struct ext4_mount_options {
5621         unsigned long s_mount_opt;
5622         unsigned long s_mount_opt2;
5623         kuid_t s_resuid;
5624         kgid_t s_resgid;
5625         unsigned long s_commit_interval;
5626         u32 s_min_batch_time, s_max_batch_time;
5627 #ifdef CONFIG_QUOTA
5628         int s_jquota_fmt;
5629         char *s_qf_names[EXT4_MAXQUOTAS];
5630 #endif
5631 };
5632
5633 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5634 {
5635         struct ext4_super_block *es;
5636         struct ext4_sb_info *sbi = EXT4_SB(sb);
5637         unsigned long old_sb_flags, vfs_flags;
5638         struct ext4_mount_options old_opts;
5639         int enable_quota = 0;
5640         ext4_group_t g;
5641         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5642         int err = 0;
5643 #ifdef CONFIG_QUOTA
5644         int i, j;
5645         char *to_free[EXT4_MAXQUOTAS];
5646 #endif
5647         char *orig_data = kstrdup(data, GFP_KERNEL);
5648
5649         if (data && !orig_data)
5650                 return -ENOMEM;
5651
5652         /* Store the original options */
5653         old_sb_flags = sb->s_flags;
5654         old_opts.s_mount_opt = sbi->s_mount_opt;
5655         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5656         old_opts.s_resuid = sbi->s_resuid;
5657         old_opts.s_resgid = sbi->s_resgid;
5658         old_opts.s_commit_interval = sbi->s_commit_interval;
5659         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5660         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5661 #ifdef CONFIG_QUOTA
5662         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5663         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5664                 if (sbi->s_qf_names[i]) {
5665                         char *qf_name = get_qf_name(sb, sbi, i);
5666
5667                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5668                         if (!old_opts.s_qf_names[i]) {
5669                                 for (j = 0; j < i; j++)
5670                                         kfree(old_opts.s_qf_names[j]);
5671                                 kfree(orig_data);
5672                                 return -ENOMEM;
5673                         }
5674                 } else
5675                         old_opts.s_qf_names[i] = NULL;
5676 #endif
5677         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5678                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5679
5680         /*
5681          * Some options can be enabled by ext4 and/or by VFS mount flag
5682          * either way we need to make sure it matches in both *flags and
5683          * s_flags. Copy those selected flags from *flags to s_flags
5684          */
5685         vfs_flags = SB_LAZYTIME | SB_I_VERSION;
5686         sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags);
5687
5688         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5689                 err = -EINVAL;
5690                 goto restore_opts;
5691         }
5692
5693         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5694             test_opt(sb, JOURNAL_CHECKSUM)) {
5695                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5696                          "during remount not supported; ignoring");
5697                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5698         }
5699
5700         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5701                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5702                         ext4_msg(sb, KERN_ERR, "can't mount with "
5703                                  "both data=journal and delalloc");
5704                         err = -EINVAL;
5705                         goto restore_opts;
5706                 }
5707                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5708                         ext4_msg(sb, KERN_ERR, "can't mount with "
5709                                  "both data=journal and dioread_nolock");
5710                         err = -EINVAL;
5711                         goto restore_opts;
5712                 }
5713         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5714                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5715                         ext4_msg(sb, KERN_ERR, "can't mount with "
5716                                 "journal_async_commit in data=ordered mode");
5717                         err = -EINVAL;
5718                         goto restore_opts;
5719                 }
5720         }
5721
5722         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5723                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5724                 err = -EINVAL;
5725                 goto restore_opts;
5726         }
5727
5728         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5729                 ext4_abort(sb, EXT4_ERR_ESHUTDOWN, "Abort forced by user");
5730
5731         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5732                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5733
5734         es = sbi->s_es;
5735
5736         if (sbi->s_journal) {
5737                 ext4_init_journal_params(sb, sbi->s_journal);
5738                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5739         }
5740
5741         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5742                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5743                         err = -EROFS;
5744                         goto restore_opts;
5745                 }
5746
5747                 if (*flags & SB_RDONLY) {
5748                         err = sync_filesystem(sb);
5749                         if (err < 0)
5750                                 goto restore_opts;
5751                         err = dquot_suspend(sb, -1);
5752                         if (err < 0)
5753                                 goto restore_opts;
5754
5755                         /*
5756                          * First of all, the unconditional stuff we have to do
5757                          * to disable replay of the journal when we next remount
5758                          */
5759                         sb->s_flags |= SB_RDONLY;
5760
5761                         /*
5762                          * OK, test if we are remounting a valid rw partition
5763                          * readonly, and if so set the rdonly flag and then
5764                          * mark the partition as valid again.
5765                          */
5766                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5767                             (sbi->s_mount_state & EXT4_VALID_FS))
5768                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5769
5770                         if (sbi->s_journal) {
5771                                 /*
5772                                  * We let remount-ro finish even if marking fs
5773                                  * as clean failed...
5774                                  */
5775                                 ext4_mark_recovery_complete(sb, es);
5776                         }
5777                         if (sbi->s_mmp_tsk)
5778                                 kthread_stop(sbi->s_mmp_tsk);
5779                 } else {
5780                         /* Make sure we can mount this feature set readwrite */
5781                         if (ext4_has_feature_readonly(sb) ||
5782                             !ext4_feature_set_ok(sb, 0)) {
5783                                 err = -EROFS;
5784                                 goto restore_opts;
5785                         }
5786                         /*
5787                          * Make sure the group descriptor checksums
5788                          * are sane.  If they aren't, refuse to remount r/w.
5789                          */
5790                         for (g = 0; g < sbi->s_groups_count; g++) {
5791                                 struct ext4_group_desc *gdp =
5792                                         ext4_get_group_desc(sb, g, NULL);
5793
5794                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5795                                         ext4_msg(sb, KERN_ERR,
5796                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5797                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5798                                                le16_to_cpu(gdp->bg_checksum));
5799                                         err = -EFSBADCRC;
5800                                         goto restore_opts;
5801                                 }
5802                         }
5803
5804                         /*
5805                          * If we have an unprocessed orphan list hanging
5806                          * around from a previously readonly bdev mount,
5807                          * require a full umount/remount for now.
5808                          */
5809                         if (es->s_last_orphan) {
5810                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5811                                        "remount RDWR because of unprocessed "
5812                                        "orphan inode list.  Please "
5813                                        "umount/remount instead");
5814                                 err = -EINVAL;
5815                                 goto restore_opts;
5816                         }
5817
5818                         /*
5819                          * Mounting a RDONLY partition read-write, so reread
5820                          * and store the current valid flag.  (It may have
5821                          * been changed by e2fsck since we originally mounted
5822                          * the partition.)
5823                          */
5824                         if (sbi->s_journal) {
5825                                 err = ext4_clear_journal_err(sb, es);
5826                                 if (err)
5827                                         goto restore_opts;
5828                         }
5829                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5830
5831                         err = ext4_setup_super(sb, es, 0);
5832                         if (err)
5833                                 goto restore_opts;
5834
5835                         sb->s_flags &= ~SB_RDONLY;
5836                         if (ext4_has_feature_mmp(sb))
5837                                 if (ext4_multi_mount_protect(sb,
5838                                                 le64_to_cpu(es->s_mmp_block))) {
5839                                         err = -EROFS;
5840                                         goto restore_opts;
5841                                 }
5842                         enable_quota = 1;
5843                 }
5844         }
5845
5846         /*
5847          * Reinitialize lazy itable initialization thread based on
5848          * current settings
5849          */
5850         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5851                 ext4_unregister_li_request(sb);
5852         else {
5853                 ext4_group_t first_not_zeroed;
5854                 first_not_zeroed = ext4_has_uninit_itable(sb);
5855                 ext4_register_li_request(sb, first_not_zeroed);
5856         }
5857
5858         /*
5859          * Handle creation of system zone data early because it can fail.
5860          * Releasing of existing data is done when we are sure remount will
5861          * succeed.
5862          */
5863         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
5864                 err = ext4_setup_system_zone(sb);
5865                 if (err)
5866                         goto restore_opts;
5867         }
5868
5869         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5870                 err = ext4_commit_super(sb, 1);
5871                 if (err)
5872                         goto restore_opts;
5873         }
5874
5875 #ifdef CONFIG_QUOTA
5876         /* Release old quota file names */
5877         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5878                 kfree(old_opts.s_qf_names[i]);
5879         if (enable_quota) {
5880                 if (sb_any_quota_suspended(sb))
5881                         dquot_resume(sb, -1);
5882                 else if (ext4_has_feature_quota(sb)) {
5883                         err = ext4_enable_quotas(sb);
5884                         if (err)
5885                                 goto restore_opts;
5886                 }
5887         }
5888 #endif
5889         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
5890                 ext4_release_system_zone(sb);
5891
5892         /*
5893          * Some options can be enabled by ext4 and/or by VFS mount flag
5894          * either way we need to make sure it matches in both *flags and
5895          * s_flags. Copy those selected flags from s_flags to *flags
5896          */
5897         *flags = (*flags & ~vfs_flags) | (sb->s_flags & vfs_flags);
5898
5899         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5900         kfree(orig_data);
5901         return 0;
5902
5903 restore_opts:
5904         sb->s_flags = old_sb_flags;
5905         sbi->s_mount_opt = old_opts.s_mount_opt;
5906         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5907         sbi->s_resuid = old_opts.s_resuid;
5908         sbi->s_resgid = old_opts.s_resgid;
5909         sbi->s_commit_interval = old_opts.s_commit_interval;
5910         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5911         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5912         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
5913                 ext4_release_system_zone(sb);
5914 #ifdef CONFIG_QUOTA
5915         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5916         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5917                 to_free[i] = get_qf_name(sb, sbi, i);
5918                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
5919         }
5920         synchronize_rcu();
5921         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5922                 kfree(to_free[i]);
5923 #endif
5924         kfree(orig_data);
5925         return err;
5926 }
5927
5928 #ifdef CONFIG_QUOTA
5929 static int ext4_statfs_project(struct super_block *sb,
5930                                kprojid_t projid, struct kstatfs *buf)
5931 {
5932         struct kqid qid;
5933         struct dquot *dquot;
5934         u64 limit;
5935         u64 curblock;
5936
5937         qid = make_kqid_projid(projid);
5938         dquot = dqget(sb, qid);
5939         if (IS_ERR(dquot))
5940                 return PTR_ERR(dquot);
5941         spin_lock(&dquot->dq_dqb_lock);
5942
5943         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
5944                              dquot->dq_dqb.dqb_bhardlimit);
5945         limit >>= sb->s_blocksize_bits;
5946
5947         if (limit && buf->f_blocks > limit) {
5948                 curblock = (dquot->dq_dqb.dqb_curspace +
5949                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5950                 buf->f_blocks = limit;
5951                 buf->f_bfree = buf->f_bavail =
5952                         (buf->f_blocks > curblock) ?
5953                          (buf->f_blocks - curblock) : 0;
5954         }
5955
5956         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
5957                              dquot->dq_dqb.dqb_ihardlimit);
5958         if (limit && buf->f_files > limit) {
5959                 buf->f_files = limit;
5960                 buf->f_ffree =
5961                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5962                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5963         }
5964
5965         spin_unlock(&dquot->dq_dqb_lock);
5966         dqput(dquot);
5967         return 0;
5968 }
5969 #endif
5970
5971 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5972 {
5973         struct super_block *sb = dentry->d_sb;
5974         struct ext4_sb_info *sbi = EXT4_SB(sb);
5975         struct ext4_super_block *es = sbi->s_es;
5976         ext4_fsblk_t overhead = 0, resv_blocks;
5977         u64 fsid;
5978         s64 bfree;
5979         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5980
5981         if (!test_opt(sb, MINIX_DF))
5982                 overhead = sbi->s_overhead;
5983
5984         buf->f_type = EXT4_SUPER_MAGIC;
5985         buf->f_bsize = sb->s_blocksize;
5986         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5987         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5988                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5989         /* prevent underflow in case that few free space is available */
5990         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5991         buf->f_bavail = buf->f_bfree -
5992                         (ext4_r_blocks_count(es) + resv_blocks);
5993         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5994                 buf->f_bavail = 0;
5995         buf->f_files = le32_to_cpu(es->s_inodes_count);
5996         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5997         buf->f_namelen = EXT4_NAME_LEN;
5998         fsid = le64_to_cpup((void *)es->s_uuid) ^
5999                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
6000         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
6001         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
6002
6003 #ifdef CONFIG_QUOTA
6004         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6005             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6006                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6007 #endif
6008         return 0;
6009 }
6010
6011
6012 #ifdef CONFIG_QUOTA
6013
6014 /*
6015  * Helper functions so that transaction is started before we acquire dqio_sem
6016  * to keep correct lock ordering of transaction > dqio_sem
6017  */
6018 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6019 {
6020         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6021 }
6022
6023 static int ext4_write_dquot(struct dquot *dquot)
6024 {
6025         int ret, err;
6026         handle_t *handle;
6027         struct inode *inode;
6028
6029         inode = dquot_to_inode(dquot);
6030         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6031                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6032         if (IS_ERR(handle))
6033                 return PTR_ERR(handle);
6034         ret = dquot_commit(dquot);
6035         err = ext4_journal_stop(handle);
6036         if (!ret)
6037                 ret = err;
6038         return ret;
6039 }
6040
6041 static int ext4_acquire_dquot(struct dquot *dquot)
6042 {
6043         int ret, err;
6044         handle_t *handle;
6045
6046         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6047                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6048         if (IS_ERR(handle))
6049                 return PTR_ERR(handle);
6050         ret = dquot_acquire(dquot);
6051         err = ext4_journal_stop(handle);
6052         if (!ret)
6053                 ret = err;
6054         return ret;
6055 }
6056
6057 static int ext4_release_dquot(struct dquot *dquot)
6058 {
6059         int ret, err;
6060         handle_t *handle;
6061
6062         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6063                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6064         if (IS_ERR(handle)) {
6065                 /* Release dquot anyway to avoid endless cycle in dqput() */
6066                 dquot_release(dquot);
6067                 return PTR_ERR(handle);
6068         }
6069         ret = dquot_release(dquot);
6070         err = ext4_journal_stop(handle);
6071         if (!ret)
6072                 ret = err;
6073         return ret;
6074 }
6075
6076 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6077 {
6078         struct super_block *sb = dquot->dq_sb;
6079         struct ext4_sb_info *sbi = EXT4_SB(sb);
6080
6081         /* Are we journaling quotas? */
6082         if (ext4_has_feature_quota(sb) ||
6083             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
6084                 dquot_mark_dquot_dirty(dquot);
6085                 return ext4_write_dquot(dquot);
6086         } else {
6087                 return dquot_mark_dquot_dirty(dquot);
6088         }
6089 }
6090
6091 static int ext4_write_info(struct super_block *sb, int type)
6092 {
6093         int ret, err;
6094         handle_t *handle;
6095
6096         /* Data block + inode block */
6097         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
6098         if (IS_ERR(handle))
6099                 return PTR_ERR(handle);
6100         ret = dquot_commit_info(sb, type);
6101         err = ext4_journal_stop(handle);
6102         if (!ret)
6103                 ret = err;
6104         return ret;
6105 }
6106
6107 /*
6108  * Turn on quotas during mount time - we need to find
6109  * the quota file and such...
6110  */
6111 static int ext4_quota_on_mount(struct super_block *sb, int type)
6112 {
6113         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
6114                                         EXT4_SB(sb)->s_jquota_fmt, type);
6115 }
6116
6117 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6118 {
6119         struct ext4_inode_info *ei = EXT4_I(inode);
6120
6121         /* The first argument of lockdep_set_subclass has to be
6122          * *exactly* the same as the argument to init_rwsem() --- in
6123          * this case, in init_once() --- or lockdep gets unhappy
6124          * because the name of the lock is set using the
6125          * stringification of the argument to init_rwsem().
6126          */
6127         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6128         lockdep_set_subclass(&ei->i_data_sem, subclass);
6129 }
6130
6131 /*
6132  * Standard function to be called on quota_on
6133  */
6134 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6135                          const struct path *path)
6136 {
6137         int err;
6138
6139         if (!test_opt(sb, QUOTA))
6140                 return -EINVAL;
6141
6142         /* Quotafile not on the same filesystem? */
6143         if (path->dentry->d_sb != sb)
6144                 return -EXDEV;
6145         /* Journaling quota? */
6146         if (EXT4_SB(sb)->s_qf_names[type]) {
6147                 /* Quotafile not in fs root? */
6148                 if (path->dentry->d_parent != sb->s_root)
6149                         ext4_msg(sb, KERN_WARNING,
6150                                 "Quota file not on filesystem root. "
6151                                 "Journaled quota will not work");
6152                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6153         } else {
6154                 /*
6155                  * Clear the flag just in case mount options changed since
6156                  * last time.
6157                  */
6158                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6159         }
6160
6161         /*
6162          * When we journal data on quota file, we have to flush journal to see
6163          * all updates to the file when we bypass pagecache...
6164          */
6165         if (EXT4_SB(sb)->s_journal &&
6166             ext4_should_journal_data(d_inode(path->dentry))) {
6167                 /*
6168                  * We don't need to lock updates but journal_flush() could
6169                  * otherwise be livelocked...
6170                  */
6171                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6172                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
6173                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6174                 if (err)
6175                         return err;
6176         }
6177
6178         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6179         err = dquot_quota_on(sb, type, format_id, path);
6180         if (err) {
6181                 lockdep_set_quota_inode(path->dentry->d_inode,
6182                                              I_DATA_SEM_NORMAL);
6183         } else {
6184                 struct inode *inode = d_inode(path->dentry);
6185                 handle_t *handle;
6186
6187                 /*
6188                  * Set inode flags to prevent userspace from messing with quota
6189                  * files. If this fails, we return success anyway since quotas
6190                  * are already enabled and this is not a hard failure.
6191                  */
6192                 inode_lock(inode);
6193                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6194                 if (IS_ERR(handle))
6195                         goto unlock_inode;
6196                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6197                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6198                                 S_NOATIME | S_IMMUTABLE);
6199                 err = ext4_mark_inode_dirty(handle, inode);
6200                 ext4_journal_stop(handle);
6201         unlock_inode:
6202                 inode_unlock(inode);
6203         }
6204         return err;
6205 }
6206
6207 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6208                              unsigned int flags)
6209 {
6210         int err;
6211         struct inode *qf_inode;
6212         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6213                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6214                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6215                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6216         };
6217
6218         BUG_ON(!ext4_has_feature_quota(sb));
6219
6220         if (!qf_inums[type])
6221                 return -EPERM;
6222
6223         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6224         if (IS_ERR(qf_inode)) {
6225                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6226                 return PTR_ERR(qf_inode);
6227         }
6228
6229         /* Don't account quota for quota files to avoid recursion */
6230         qf_inode->i_flags |= S_NOQUOTA;
6231         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6232         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6233         if (err)
6234                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6235         iput(qf_inode);
6236
6237         return err;
6238 }
6239
6240 /* Enable usage tracking for all quota types. */
6241 static int ext4_enable_quotas(struct super_block *sb)
6242 {
6243         int type, err = 0;
6244         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6245                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6246                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6247                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6248         };
6249         bool quota_mopt[EXT4_MAXQUOTAS] = {
6250                 test_opt(sb, USRQUOTA),
6251                 test_opt(sb, GRPQUOTA),
6252                 test_opt(sb, PRJQUOTA),
6253         };
6254
6255         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6256         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6257                 if (qf_inums[type]) {
6258                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6259                                 DQUOT_USAGE_ENABLED |
6260                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6261                         if (err) {
6262                                 ext4_warning(sb,
6263                                         "Failed to enable quota tracking "
6264                                         "(type=%d, err=%d). Please run "
6265                                         "e2fsck to fix.", type, err);
6266                                 for (type--; type >= 0; type--)
6267                                         dquot_quota_off(sb, type);
6268
6269                                 return err;
6270                         }
6271                 }
6272         }
6273         return 0;
6274 }
6275
6276 static int ext4_quota_off(struct super_block *sb, int type)
6277 {
6278         struct inode *inode = sb_dqopt(sb)->files[type];
6279         handle_t *handle;
6280         int err;
6281
6282         /* Force all delayed allocation blocks to be allocated.
6283          * Caller already holds s_umount sem */
6284         if (test_opt(sb, DELALLOC))
6285                 sync_filesystem(sb);
6286
6287         if (!inode || !igrab(inode))
6288                 goto out;
6289
6290         err = dquot_quota_off(sb, type);
6291         if (err || ext4_has_feature_quota(sb))
6292                 goto out_put;
6293
6294         inode_lock(inode);
6295         /*
6296          * Update modification times of quota files when userspace can
6297          * start looking at them. If we fail, we return success anyway since
6298          * this is not a hard failure and quotas are already disabled.
6299          */
6300         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6301         if (IS_ERR(handle)) {
6302                 err = PTR_ERR(handle);
6303                 goto out_unlock;
6304         }
6305         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6306         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6307         inode->i_mtime = inode->i_ctime = current_time(inode);
6308         err = ext4_mark_inode_dirty(handle, inode);
6309         ext4_journal_stop(handle);
6310 out_unlock:
6311         inode_unlock(inode);
6312 out_put:
6313         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6314         iput(inode);
6315         return err;
6316 out:
6317         return dquot_quota_off(sb, type);
6318 }
6319
6320 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6321  * acquiring the locks... As quota files are never truncated and quota code
6322  * itself serializes the operations (and no one else should touch the files)
6323  * we don't have to be afraid of races */
6324 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6325                                size_t len, loff_t off)
6326 {
6327         struct inode *inode = sb_dqopt(sb)->files[type];
6328         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6329         int offset = off & (sb->s_blocksize - 1);
6330         int tocopy;
6331         size_t toread;
6332         struct buffer_head *bh;
6333         loff_t i_size = i_size_read(inode);
6334
6335         if (off > i_size)
6336                 return 0;
6337         if (off+len > i_size)
6338                 len = i_size-off;
6339         toread = len;
6340         while (toread > 0) {
6341                 tocopy = sb->s_blocksize - offset < toread ?
6342                                 sb->s_blocksize - offset : toread;
6343                 bh = ext4_bread(NULL, inode, blk, 0);
6344                 if (IS_ERR(bh))
6345                         return PTR_ERR(bh);
6346                 if (!bh)        /* A hole? */
6347                         memset(data, 0, tocopy);
6348                 else
6349                         memcpy(data, bh->b_data+offset, tocopy);
6350                 brelse(bh);
6351                 offset = 0;
6352                 toread -= tocopy;
6353                 data += tocopy;
6354                 blk++;
6355         }
6356         return len;
6357 }
6358
6359 /* Write to quotafile (we know the transaction is already started and has
6360  * enough credits) */
6361 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6362                                 const char *data, size_t len, loff_t off)
6363 {
6364         struct inode *inode = sb_dqopt(sb)->files[type];
6365         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6366         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6367         int retries = 0;
6368         struct buffer_head *bh;
6369         handle_t *handle = journal_current_handle();
6370
6371         if (EXT4_SB(sb)->s_journal && !handle) {
6372                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6373                         " cancelled because transaction is not started",
6374                         (unsigned long long)off, (unsigned long long)len);
6375                 return -EIO;
6376         }
6377         /*
6378          * Since we account only one data block in transaction credits,
6379          * then it is impossible to cross a block boundary.
6380          */
6381         if (sb->s_blocksize - offset < len) {
6382                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6383                         " cancelled because not block aligned",
6384                         (unsigned long long)off, (unsigned long long)len);
6385                 return -EIO;
6386         }
6387
6388         do {
6389                 bh = ext4_bread(handle, inode, blk,
6390                                 EXT4_GET_BLOCKS_CREATE |
6391                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6392         } while (PTR_ERR(bh) == -ENOSPC &&
6393                  ext4_should_retry_alloc(inode->i_sb, &retries));
6394         if (IS_ERR(bh))
6395                 return PTR_ERR(bh);
6396         if (!bh)
6397                 goto out;
6398         BUFFER_TRACE(bh, "get write access");
6399         err = ext4_journal_get_write_access(handle, bh);
6400         if (err) {
6401                 brelse(bh);
6402                 return err;
6403         }
6404         lock_buffer(bh);
6405         memcpy(bh->b_data+offset, data, len);
6406         flush_dcache_page(bh->b_page);
6407         unlock_buffer(bh);
6408         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6409         brelse(bh);
6410 out:
6411         if (inode->i_size < off + len) {
6412                 i_size_write(inode, off + len);
6413                 EXT4_I(inode)->i_disksize = inode->i_size;
6414                 err2 = ext4_mark_inode_dirty(handle, inode);
6415                 if (unlikely(err2 && !err))
6416                         err = err2;
6417         }
6418         return err ? err : len;
6419 }
6420 #endif
6421
6422 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6423                        const char *dev_name, void *data)
6424 {
6425         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6426 }
6427
6428 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6429 static inline void register_as_ext2(void)
6430 {
6431         int err = register_filesystem(&ext2_fs_type);
6432         if (err)
6433                 printk(KERN_WARNING
6434                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6435 }
6436
6437 static inline void unregister_as_ext2(void)
6438 {
6439         unregister_filesystem(&ext2_fs_type);
6440 }
6441
6442 static inline int ext2_feature_set_ok(struct super_block *sb)
6443 {
6444         if (ext4_has_unknown_ext2_incompat_features(sb))
6445                 return 0;
6446         if (sb_rdonly(sb))
6447                 return 1;
6448         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6449                 return 0;
6450         return 1;
6451 }
6452 #else
6453 static inline void register_as_ext2(void) { }
6454 static inline void unregister_as_ext2(void) { }
6455 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6456 #endif
6457
6458 static inline void register_as_ext3(void)
6459 {
6460         int err = register_filesystem(&ext3_fs_type);
6461         if (err)
6462                 printk(KERN_WARNING
6463                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6464 }
6465
6466 static inline void unregister_as_ext3(void)
6467 {
6468         unregister_filesystem(&ext3_fs_type);
6469 }
6470
6471 static inline int ext3_feature_set_ok(struct super_block *sb)
6472 {
6473         if (ext4_has_unknown_ext3_incompat_features(sb))
6474                 return 0;
6475         if (!ext4_has_feature_journal(sb))
6476                 return 0;
6477         if (sb_rdonly(sb))
6478                 return 1;
6479         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6480                 return 0;
6481         return 1;
6482 }
6483
6484 static struct file_system_type ext4_fs_type = {
6485         .owner          = THIS_MODULE,
6486         .name           = "ext4",
6487         .mount          = ext4_mount,
6488         .kill_sb        = kill_block_super,
6489         .fs_flags       = FS_REQUIRES_DEV,
6490 };
6491 MODULE_ALIAS_FS("ext4");
6492
6493 /* Shared across all ext4 file systems */
6494 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6495
6496 static int __init ext4_init_fs(void)
6497 {
6498         int i, err;
6499
6500         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6501         ext4_li_info = NULL;
6502         mutex_init(&ext4_li_mtx);
6503
6504         /* Build-time check for flags consistency */
6505         ext4_check_flag_values();
6506
6507         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6508                 init_waitqueue_head(&ext4__ioend_wq[i]);
6509
6510         err = ext4_init_es();
6511         if (err)
6512                 return err;
6513
6514         err = ext4_init_pending();
6515         if (err)
6516                 goto out7;
6517
6518         err = ext4_init_post_read_processing();
6519         if (err)
6520                 goto out6;
6521
6522         err = ext4_init_pageio();
6523         if (err)
6524                 goto out5;
6525
6526         err = ext4_init_system_zone();
6527         if (err)
6528                 goto out4;
6529
6530         err = ext4_init_sysfs();
6531         if (err)
6532                 goto out3;
6533
6534         err = ext4_init_mballoc();
6535         if (err)
6536                 goto out2;
6537         err = init_inodecache();
6538         if (err)
6539                 goto out1;
6540         register_as_ext3();
6541         register_as_ext2();
6542         err = register_filesystem(&ext4_fs_type);
6543         if (err)
6544                 goto out;
6545
6546         return 0;
6547 out:
6548         unregister_as_ext2();
6549         unregister_as_ext3();
6550         destroy_inodecache();
6551 out1:
6552         ext4_exit_mballoc();
6553 out2:
6554         ext4_exit_sysfs();
6555 out3:
6556         ext4_exit_system_zone();
6557 out4:
6558         ext4_exit_pageio();
6559 out5:
6560         ext4_exit_post_read_processing();
6561 out6:
6562         ext4_exit_pending();
6563 out7:
6564         ext4_exit_es();
6565
6566         return err;
6567 }
6568
6569 static void __exit ext4_exit_fs(void)
6570 {
6571         ext4_destroy_lazyinit_thread();
6572         unregister_as_ext2();
6573         unregister_as_ext3();
6574         unregister_filesystem(&ext4_fs_type);
6575         destroy_inodecache();
6576         ext4_exit_mballoc();
6577         ext4_exit_sysfs();
6578         ext4_exit_system_zone();
6579         ext4_exit_pageio();
6580         ext4_exit_post_read_processing();
6581         ext4_exit_es();
6582         ext4_exit_pending();
6583 }
6584
6585 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6586 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6587 MODULE_LICENSE("GPL");
6588 MODULE_SOFTDEP("pre: crc32c");
6589 module_init(ext4_init_fs)
6590 module_exit(ext4_exit_fs)