fs/ext4/super.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/ext4/super.c
   4  *
   5  * Copyright (C) 1992, 1993, 1994, 1995
   6  * Remy Card (card@masi.ibp.fr)
   7  * Laboratoire MASI - Institut Blaise Pascal
   8  * Universite Pierre et Marie Curie (Paris VI)
   9  *
  10  *  from
  11  *
  12  *  linux/fs/minix/inode.c
  13  *
  14  *  Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  *  Big-endian to little-endian byte-swapping/bitmaps by
  17  *        David S. Miller (davem@caip.rutgers.edu), 1995
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/string.h>
  22 #include <linux/fs.h>
  23 #include <linux/time.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/backing-dev.h>
  29 #include <linux/parser.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/dax.h>
  42 #include <linux/cleancache.h>
  43 #include <linux/uaccess.h>
  44 #include <linux/iversion.h>
  45 #include <linux/unicode.h>
  46 #include <linux/part_stat.h>
  47 #include <linux/kthread.h>
  48 #include <linux/freezer.h>
  49
  50 #include "ext4.h"
  51 #include "ext4_extents.h"       /* Needed for trace points definition */
  52 #include "ext4_jbd2.h"
  53 #include "xattr.h"
  54 #include "acl.h"
  55 #include "mballoc.h"
  56 #include "fsmap.h"
  57
  58 #define CREATE_TRACE_POINTS
  59 #include <trace/events/ext4.h>
  60
  61 static struct ext4_lazy_init *ext4_li_info;
  62 static struct mutex ext4_li_mtx;
  63 static struct ratelimit_state ext4_mount_msg_ratelimit;
  64
  65 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  66                              unsigned long journal_devnum);
  67 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  68 static int ext4_commit_super(struct super_block *sb, int sync);
  69 static int ext4_mark_recovery_complete(struct super_block *sb,
  70                                         struct ext4_super_block *es);
  71 static int ext4_clear_journal_err(struct super_block *sb,
  72                                   struct ext4_super_block *es);
  73 static int ext4_sync_fs(struct super_block *sb, int wait);
  74 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  75 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  76 static int ext4_unfreeze(struct super_block *sb);
  77 static int ext4_freeze(struct super_block *sb);
  78 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  79                        const char *dev_name, void *data);
  80 static inline int ext2_feature_set_ok(struct super_block *sb);
  81 static inline int ext3_feature_set_ok(struct super_block *sb);
  82 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  83 static void ext4_destroy_lazyinit_thread(void);
  84 static void ext4_unregister_li_request(struct super_block *sb);
  85 static void ext4_clear_request_list(void);
  86 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  87                                             unsigned int journal_inum);
  88
  89 /*
  90  * Lock ordering
  91  *
  92  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
  93  * i_mmap_rwsem (inode->i_mmap_rwsem)!
  94  *
  95  * page fault path:
  96  * mmap_lock -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
  97  *   page lock -> i_data_sem (rw)
  98  *
  99  * buffered write path:
 100  * sb_start_write -> i_mutex -> mmap_lock
 101  * sb_start_write -> i_mutex -> transaction start -> page lock ->
 102  *   i_data_sem (rw)
 103  *
 104  * truncate:
 105  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> i_mmap_rwsem (w) -> page lock
 106  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> transaction start ->
 107  *   i_data_sem (rw)
 108  *
 109  * direct IO:
 110  * sb_start_write -> i_mutex -> mmap_lock
 111  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
 112  *
 113  * writepages:
 114  * transaction start -> page lock(s) -> i_data_sem (rw)
 115  */
 116
 117 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 118 static struct file_system_type ext2_fs_type = {
 119         .owner          = THIS_MODULE,
 120         .name           = "ext2",
 121         .mount          = ext4_mount,
 122         .kill_sb        = kill_block_super,
 123         .fs_flags       = FS_REQUIRES_DEV,
 124 };
 125 MODULE_ALIAS_FS("ext2");
 126 MODULE_ALIAS("ext2");
 127 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
 128 #else
 129 #define IS_EXT2_SB(sb) (0)
 130 #endif
 131
 132
 133 static struct file_system_type ext3_fs_type = {
 134         .owner          = THIS_MODULE,
 135         .name           = "ext3",
 136         .mount          = ext4_mount,
 137         .kill_sb        = kill_block_super,
 138         .fs_flags       = FS_REQUIRES_DEV,
 139 };
 140 MODULE_ALIAS_FS("ext3");
 141 MODULE_ALIAS("ext3");
 142 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 143
 144
 145 static inline void __ext4_read_bh(struct buffer_head *bh, int op_flags,
 146                                   bh_end_io_t *end_io)
 147 {
 148         /*
 149          * buffer's verified bit is no longer valid after reading from
 150          * disk again due to write out error, clear it to make sure we
 151          * recheck the buffer contents.
 152          */
 153         clear_buffer_verified(bh);
 154
 155         bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
 156         get_bh(bh);
 157         submit_bh(REQ_OP_READ, op_flags, bh);
 158 }
 159
 160 void ext4_read_bh_nowait(struct buffer_head *bh, int op_flags,
 161                          bh_end_io_t *end_io)
 162 {
 163         BUG_ON(!buffer_locked(bh));
 164
 165         if (ext4_buffer_uptodate(bh)) {
 166                 unlock_buffer(bh);
 167                 return;
 168         }
 169         __ext4_read_bh(bh, op_flags, end_io);
 170 }
 171
 172 int ext4_read_bh(struct buffer_head *bh, int op_flags, bh_end_io_t *end_io)
 173 {
 174         BUG_ON(!buffer_locked(bh));
 175
 176         if (ext4_buffer_uptodate(bh)) {
 177                 unlock_buffer(bh);
 178                 return 0;
 179         }
 180
 181         __ext4_read_bh(bh, op_flags, end_io);
 182
 183         wait_on_buffer(bh);
 184         if (buffer_uptodate(bh))
 185                 return 0;
 186         return -EIO;
 187 }
 188
 189 int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait)
 190 {
 191         if (trylock_buffer(bh)) {
 192                 if (wait)
 193                         return ext4_read_bh(bh, op_flags, NULL);
 194                 ext4_read_bh_nowait(bh, op_flags, NULL);
 195                 return 0;
 196         }
 197         if (wait) {
 198                 wait_on_buffer(bh);
 199                 if (buffer_uptodate(bh))
 200                         return 0;
 201                 return -EIO;
 202         }
 203         return 0;
 204 }
 205
 206 /*
 207  * This works like __bread_gfp() except it uses ERR_PTR for error
 208  * returns.  Currently with sb_bread it's impossible to distinguish
 209  * between ENOMEM and EIO situations (since both result in a NULL
 210  * return.
 211  */
 212 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
 213                                                sector_t block, int op_flags,
 214                                                gfp_t gfp)
 215 {
 216         struct buffer_head *bh;
 217         int ret;
 218
 219         bh = sb_getblk_gfp(sb, block, gfp);
 220         if (bh == NULL)
 221                 return ERR_PTR(-ENOMEM);
 222         if (ext4_buffer_uptodate(bh))
 223                 return bh;
 224
 225         ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
 226         if (ret) {
 227                 put_bh(bh);
 228                 return ERR_PTR(ret);
 229         }
 230         return bh;
 231 }
 232
 233 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
 234                                    int op_flags)
 235 {
 236         return __ext4_sb_bread_gfp(sb, block, op_flags, __GFP_MOVABLE);
 237 }
 238
 239 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
 240                                             sector_t block)
 241 {
 242         return __ext4_sb_bread_gfp(sb, block, 0, 0);
 243 }
 244
 245 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
 246 {
 247         struct buffer_head *bh = sb_getblk_gfp(sb, block, 0);
 248
 249         if (likely(bh)) {
 250                 ext4_read_bh_lock(bh, REQ_RAHEAD, false);
 251                 brelse(bh);
 252         }
 253 }
 254
 255 static int ext4_verify_csum_type(struct super_block *sb,
 256                                  struct ext4_super_block *es)
 257 {
 258         if (!ext4_has_feature_metadata_csum(sb))
 259                 return 1;
 260
 261         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 262 }
 263
 264 static __le32 ext4_superblock_csum(struct super_block *sb,
 265                                    struct ext4_super_block *es)
 266 {
 267         struct ext4_sb_info *sbi = EXT4_SB(sb);
 268         int offset = offsetof(struct ext4_super_block, s_checksum);
 269         __u32 csum;
 270
 271         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 272
 273         return cpu_to_le32(csum);
 274 }
 275
 276 static int ext4_superblock_csum_verify(struct super_block *sb,
 277                                        struct ext4_super_block *es)
 278 {
 279         if (!ext4_has_metadata_csum(sb))
 280                 return 1;
 281
 282         return es->s_checksum == ext4_superblock_csum(sb, es);
 283 }
 284
 285 void ext4_superblock_csum_set(struct super_block *sb)
 286 {
 287         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 288
 289         if (!ext4_has_metadata_csum(sb))
 290                 return;
 291
 292         /*
 293          * Locking the superblock prevents the scenario
 294          * where:
 295          *  1) a first thread pauses during checksum calculation.
 296          *  2) a second thread updates the superblock, recalculates
 297          *     the checksum, and updates s_checksum
 298          *  3) the first thread resumes and finishes its checksum calculation
 299          *     and updates s_checksum with a potentially stale or torn value.
 300          */
 301         lock_buffer(EXT4_SB(sb)->s_sbh);
 302         es->s_checksum = ext4_superblock_csum(sb, es);
 303         unlock_buffer(EXT4_SB(sb)->s_sbh);
 304 }
 305
 306 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 307                                struct ext4_group_desc *bg)
 308 {
 309         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 310                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 311                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 312 }
 313
 314 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 315                                struct ext4_group_desc *bg)
 316 {
 317         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 318                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 319                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 320 }
 321
 322 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 323                               struct ext4_group_desc *bg)
 324 {
 325         return le32_to_cpu(bg->bg_inode_table_lo) |
 326                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 327                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 328 }
 329
 330 __u32 ext4_free_group_clusters(struct super_block *sb,
 331                                struct ext4_group_desc *bg)
 332 {
 333         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 334                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 335                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 336 }
 337
 338 __u32 ext4_free_inodes_count(struct super_block *sb,
 339                               struct ext4_group_desc *bg)
 340 {
 341         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 342                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 343                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 344 }
 345
 346 __u32 ext4_used_dirs_count(struct super_block *sb,
 347                               struct ext4_group_desc *bg)
 348 {
 349         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 350                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 351                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 352 }
 353
 354 __u32 ext4_itable_unused_count(struct super_block *sb,
 355                               struct ext4_group_desc *bg)
 356 {
 357         return le16_to_cpu(bg->bg_itable_unused_lo) |
 358                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 359                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 360 }
 361
 362 void ext4_block_bitmap_set(struct super_block *sb,
 363                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 364 {
 365         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 366         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 367                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 368 }
 369
 370 void ext4_inode_bitmap_set(struct super_block *sb,
 371                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 372 {
 373         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 374         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 375                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 376 }
 377
 378 void ext4_inode_table_set(struct super_block *sb,
 379                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 380 {
 381         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 382         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 383                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 384 }
 385
 386 void ext4_free_group_clusters_set(struct super_block *sb,
 387                                   struct ext4_group_desc *bg, __u32 count)
 388 {
 389         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 390         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 391                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 392 }
 393
 394 void ext4_free_inodes_set(struct super_block *sb,
 395                           struct ext4_group_desc *bg, __u32 count)
 396 {
 397         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 398         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 399                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 400 }
 401
 402 void ext4_used_dirs_set(struct super_block *sb,
 403                           struct ext4_group_desc *bg, __u32 count)
 404 {
 405         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 406         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 407                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 408 }
 409
 410 void ext4_itable_unused_set(struct super_block *sb,
 411                           struct ext4_group_desc *bg, __u32 count)
 412 {
 413         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 414         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 415                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 416 }
 417
 418 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi)
 419 {
 420         time64_t now = ktime_get_real_seconds();
 421
 422         now = clamp_val(now, 0, (1ull << 40) - 1);
 423
 424         *lo = cpu_to_le32(lower_32_bits(now));
 425         *hi = upper_32_bits(now);
 426 }
 427
 428 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 429 {
 430         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 431 }
 432 #define ext4_update_tstamp(es, tstamp) \
 433         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 434 #define ext4_get_tstamp(es, tstamp) \
 435         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 436
 437 static void __save_error_info(struct super_block *sb, int error,
 438                               __u32 ino, __u64 block,
 439                               const char *func, unsigned int line)
 440 {
 441         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 442         int err;
 443
 444         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 445         if (bdev_read_only(sb->s_bdev))
 446                 return;
 447         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 448         ext4_update_tstamp(es, s_last_error_time);
 449         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 450         es->s_last_error_line = cpu_to_le32(line);
 451         es->s_last_error_ino = cpu_to_le32(ino);
 452         es->s_last_error_block = cpu_to_le64(block);
 453         switch (error) {
 454         case EIO:
 455                 err = EXT4_ERR_EIO;
 456                 break;
 457         case ENOMEM:
 458                 err = EXT4_ERR_ENOMEM;
 459                 break;
 460         case EFSBADCRC:
 461                 err = EXT4_ERR_EFSBADCRC;
 462                 break;
 463         case 0:
 464         case EFSCORRUPTED:
 465                 err = EXT4_ERR_EFSCORRUPTED;
 466                 break;
 467         case ENOSPC:
 468                 err = EXT4_ERR_ENOSPC;
 469                 break;
 470         case ENOKEY:
 471                 err = EXT4_ERR_ENOKEY;
 472                 break;
 473         case EROFS:
 474                 err = EXT4_ERR_EROFS;
 475                 break;
 476         case EFBIG:
 477                 err = EXT4_ERR_EFBIG;
 478                 break;
 479         case EEXIST:
 480                 err = EXT4_ERR_EEXIST;
 481                 break;
 482         case ERANGE:
 483                 err = EXT4_ERR_ERANGE;
 484                 break;
 485         case EOVERFLOW:
 486                 err = EXT4_ERR_EOVERFLOW;
 487                 break;
 488         case EBUSY:
 489                 err = EXT4_ERR_EBUSY;
 490                 break;
 491         case ENOTDIR:
 492                 err = EXT4_ERR_ENOTDIR;
 493                 break;
 494         case ENOTEMPTY:
 495                 err = EXT4_ERR_ENOTEMPTY;
 496                 break;
 497         case ESHUTDOWN:
 498                 err = EXT4_ERR_ESHUTDOWN;
 499                 break;
 500         case EFAULT:
 501                 err = EXT4_ERR_EFAULT;
 502                 break;
 503         default:
 504                 err = EXT4_ERR_UNKNOWN;
 505         }
 506         es->s_last_error_errcode = err;
 507         if (!es->s_first_error_time) {
 508                 es->s_first_error_time = es->s_last_error_time;
 509                 es->s_first_error_time_hi = es->s_last_error_time_hi;
 510                 strncpy(es->s_first_error_func, func,
 511                         sizeof(es->s_first_error_func));
 512                 es->s_first_error_line = cpu_to_le32(line);
 513                 es->s_first_error_ino = es->s_last_error_ino;
 514                 es->s_first_error_block = es->s_last_error_block;
 515                 es->s_first_error_errcode = es->s_last_error_errcode;
 516         }
 517         /*
 518          * Start the daily error reporting function if it hasn't been
 519          * started already
 520          */
 521         if (!es->s_error_count)
 522                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 523         le32_add_cpu(&es->s_error_count, 1);
 524 }
 525
 526 static void save_error_info(struct super_block *sb, int error,
 527                             __u32 ino, __u64 block,
 528                             const char *func, unsigned int line)
 529 {
 530         __save_error_info(sb, error, ino, block, func, line);
 531         if (!bdev_read_only(sb->s_bdev))
 532                 ext4_commit_super(sb, 1);
 533 }
 534
 535 /*
 536  * The del_gendisk() function uninitializes the disk-specific data
 537  * structures, including the bdi structure, without telling anyone
 538  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 539  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 540  * This is a kludge to prevent these oops until we can put in a proper
 541  * hook in del_gendisk() to inform the VFS and file system layers.
 542  */
 543 static int block_device_ejected(struct super_block *sb)
 544 {
 545         struct inode *bd_inode = sb->s_bdev->bd_inode;
 546         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 547
 548         return bdi->dev == NULL;
 549 }
 550
 551 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 552 {
 553         struct super_block              *sb = journal->j_private;
 554         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 555         int                             error = is_journal_aborted(journal);
 556         struct ext4_journal_cb_entry    *jce;
 557
 558         BUG_ON(txn->t_state == T_FINISHED);
 559
 560         ext4_process_freed_data(sb, txn->t_tid);
 561
 562         spin_lock(&sbi->s_md_lock);
 563         while (!list_empty(&txn->t_private_list)) {
 564                 jce = list_entry(txn->t_private_list.next,
 565                                  struct ext4_journal_cb_entry, jce_list);
 566                 list_del_init(&jce->jce_list);
 567                 spin_unlock(&sbi->s_md_lock);
 568                 jce->jce_func(sb, jce, error);
 569                 spin_lock(&sbi->s_md_lock);
 570         }
 571         spin_unlock(&sbi->s_md_lock);
 572 }
 573
 574 /*
 575  * This writepage callback for write_cache_pages()
 576  * takes care of a few cases after page cleaning.
 577  *
 578  * write_cache_pages() already checks for dirty pages
 579  * and calls clear_page_dirty_for_io(), which we want,
 580  * to write protect the pages.
 581  *
 582  * However, we may have to redirty a page (see below.)
 583  */
 584 static int ext4_journalled_writepage_callback(struct page *page,
 585                                               struct writeback_control *wbc,
 586                                               void *data)
 587 {
 588         transaction_t *transaction = (transaction_t *) data;
 589         struct buffer_head *bh, *head;
 590         struct journal_head *jh;
 591
 592         bh = head = page_buffers(page);
 593         do {
 594                 /*
 595                  * We have to redirty a page in these cases:
 596                  * 1) If buffer is dirty, it means the page was dirty because it
 597                  * contains a buffer that needs checkpointing. So the dirty bit
 598                  * needs to be preserved so that checkpointing writes the buffer
 599                  * properly.
 600                  * 2) If buffer is not part of the committing transaction
 601                  * (we may have just accidentally come across this buffer because
 602                  * inode range tracking is not exact) or if the currently running
 603                  * transaction already contains this buffer as well, dirty bit
 604                  * needs to be preserved so that the buffer gets writeprotected
 605                  * properly on running transaction's commit.
 606                  */
 607                 jh = bh2jh(bh);
 608                 if (buffer_dirty(bh) ||
 609                     (jh && (jh->b_transaction != transaction ||
 610                             jh->b_next_transaction))) {
 611                         redirty_page_for_writepage(wbc, page);
 612                         goto out;
 613                 }
 614         } while ((bh = bh->b_this_page) != head);
 615
 616 out:
 617         return AOP_WRITEPAGE_ACTIVATE;
 618 }
 619
 620 static int ext4_journalled_submit_inode_data_buffers(struct jbd2_inode *jinode)
 621 {
 622         struct address_space *mapping = jinode->i_vfs_inode->i_mapping;
 623         struct writeback_control wbc = {
 624                 .sync_mode =  WB_SYNC_ALL,
 625                 .nr_to_write = LONG_MAX,
 626                 .range_start = jinode->i_dirty_start,
 627                 .range_end = jinode->i_dirty_end,
 628         };
 629
 630         return write_cache_pages(mapping, &wbc,
 631                                  ext4_journalled_writepage_callback,
 632                                  jinode->i_transaction);
 633 }
 634
 635 static int ext4_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
 636 {
 637         int ret;
 638
 639         if (ext4_should_journal_data(jinode->i_vfs_inode))
 640                 ret = ext4_journalled_submit_inode_data_buffers(jinode);
 641         else
 642                 ret = jbd2_journal_submit_inode_data_buffers(jinode);
 643
 644         return ret;
 645 }
 646
 647 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
 648 {
 649         int ret = 0;
 650
 651         if (!ext4_should_journal_data(jinode->i_vfs_inode))
 652                 ret = jbd2_journal_finish_inode_data_buffers(jinode);
 653
 654         return ret;
 655 }
 656
 657 static bool system_going_down(void)
 658 {
 659         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 660                 || system_state == SYSTEM_RESTART;
 661 }
 662
 663 /* Deal with the reporting of failure conditions on a filesystem such as
 664  * inconsistencies detected or read IO failures.
 665  *
 666  * On ext2, we can store the error state of the filesystem in the
 667  * superblock.  That is not possible on ext4, because we may have other
 668  * write ordering constraints on the superblock which prevent us from
 669  * writing it out straight away; and given that the journal is about to
 670  * be aborted, we can't rely on the current, or future, transactions to
 671  * write out the superblock safely.
 672  *
 673  * We'll just use the jbd2_journal_abort() error code to record an error in
 674  * the journal instead.  On recovery, the journal will complain about
 675  * that error until we've noted it down and cleared it.
 676  */
 677
 678 static void ext4_handle_error(struct super_block *sb)
 679 {
 680         if (test_opt(sb, WARN_ON_ERROR))
 681                 WARN_ON_ONCE(1);
 682
 683         if (sb_rdonly(sb))
 684                 return;
 685
 686         if (!test_opt(sb, ERRORS_CONT)) {
 687                 journal_t *journal = EXT4_SB(sb)->s_journal;
 688
 689                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 690                 if (journal)
 691                         jbd2_journal_abort(journal, -EIO);
 692         }
 693         /*
 694          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 695          * could panic during 'reboot -f' as the underlying device got already
 696          * disabled.
 697          */
 698         if (test_opt(sb, ERRORS_RO) || system_going_down()) {
 699                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 700                 /*
 701                  * Make sure updated value of ->s_mount_flags will be visible
 702                  * before ->s_flags update
 703                  */
 704                 smp_wmb();
 705                 sb->s_flags |= SB_RDONLY;
 706         } else if (test_opt(sb, ERRORS_PANIC)) {
 707                 panic("EXT4-fs (device %s): panic forced after error\n",
 708                         sb->s_id);
 709         }
 710 }
 711
 712 #define ext4_error_ratelimit(sb)                                        \
 713                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 714                              "EXT4-fs error")
 715
 716 void __ext4_error(struct super_block *sb, const char *function,
 717                   unsigned int line, int error, __u64 block,
 718                   const char *fmt, ...)
 719 {
 720         struct va_format vaf;
 721         va_list args;
 722
 723         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 724                 return;
 725
 726         trace_ext4_error(sb, function, line);
 727         if (ext4_error_ratelimit(sb)) {
 728                 va_start(args, fmt);
 729                 vaf.fmt = fmt;
 730                 vaf.va = &args;
 731                 printk(KERN_CRIT
 732                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 733                        sb->s_id, function, line, current->comm, &vaf);
 734                 va_end(args);
 735         }
 736         save_error_info(sb, error, 0, block, function, line);
 737         ext4_handle_error(sb);
 738 }
 739
 740 void __ext4_error_inode(struct inode *inode, const char *function,
 741                         unsigned int line, ext4_fsblk_t block, int error,
 742                         const char *fmt, ...)
 743 {
 744         va_list args;
 745         struct va_format vaf;
 746
 747         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 748                 return;
 749
 750         trace_ext4_error(inode->i_sb, function, line);
 751         if (ext4_error_ratelimit(inode->i_sb)) {
 752                 va_start(args, fmt);
 753                 vaf.fmt = fmt;
 754                 vaf.va = &args;
 755                 if (block)
 756                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 757                                "inode #%lu: block %llu: comm %s: %pV\n",
 758                                inode->i_sb->s_id, function, line, inode->i_ino,
 759                                block, current->comm, &vaf);
 760                 else
 761                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 762                                "inode #%lu: comm %s: %pV\n",
 763                                inode->i_sb->s_id, function, line, inode->i_ino,
 764                                current->comm, &vaf);
 765                 va_end(args);
 766         }
 767         save_error_info(inode->i_sb, error, inode->i_ino, block,
 768                         function, line);
 769         ext4_handle_error(inode->i_sb);
 770 }
 771
 772 void __ext4_error_file(struct file *file, const char *function,
 773                        unsigned int line, ext4_fsblk_t block,
 774                        const char *fmt, ...)
 775 {
 776         va_list args;
 777         struct va_format vaf;
 778         struct inode *inode = file_inode(file);
 779         char pathname[80], *path;
 780
 781         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 782                 return;
 783
 784         trace_ext4_error(inode->i_sb, function, line);
 785         if (ext4_error_ratelimit(inode->i_sb)) {
 786                 path = file_path(file, pathname, sizeof(pathname));
 787                 if (IS_ERR(path))
 788                         path = "(unknown)";
 789                 va_start(args, fmt);
 790                 vaf.fmt = fmt;
 791                 vaf.va = &args;
 792                 if (block)
 793                         printk(KERN_CRIT
 794                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 795                                "block %llu: comm %s: path %s: %pV\n",
 796                                inode->i_sb->s_id, function, line, inode->i_ino,
 797                                block, current->comm, path, &vaf);
 798                 else
 799                         printk(KERN_CRIT
 800                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 801                                "comm %s: path %s: %pV\n",
 802                                inode->i_sb->s_id, function, line, inode->i_ino,
 803                                current->comm, path, &vaf);
 804                 va_end(args);
 805         }
 806         save_error_info(inode->i_sb, EFSCORRUPTED, inode->i_ino, block,
 807                         function, line);
 808         ext4_handle_error(inode->i_sb);
 809 }
 810
 811 const char *ext4_decode_error(struct super_block *sb, int errno,
 812                               char nbuf[16])
 813 {
 814         char *errstr = NULL;
 815
 816         switch (errno) {
 817         case -EFSCORRUPTED:
 818                 errstr = "Corrupt filesystem";
 819                 break;
 820         case -EFSBADCRC:
 821                 errstr = "Filesystem failed CRC";
 822                 break;
 823         case -EIO:
 824                 errstr = "IO failure";
 825                 break;
 826         case -ENOMEM:
 827                 errstr = "Out of memory";
 828                 break;
 829         case -EROFS:
 830                 if (!sb || (EXT4_SB(sb)->s_journal &&
 831                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 832                         errstr = "Journal has aborted";
 833                 else
 834                         errstr = "Readonly filesystem";
 835                 break;
 836         default:
 837                 /* If the caller passed in an extra buffer for unknown
 838                  * errors, textualise them now.  Else we just return
 839                  * NULL. */
 840                 if (nbuf) {
 841                         /* Check for truncated error codes... */
 842                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 843                                 errstr = nbuf;
 844                 }
 845                 break;
 846         }
 847
 848         return errstr;
 849 }
 850
 851 /* __ext4_std_error decodes expected errors from journaling functions
 852  * automatically and invokes the appropriate error response.  */
 853
 854 void __ext4_std_error(struct super_block *sb, const char *function,
 855                       unsigned int line, int errno)
 856 {
 857         char nbuf[16];
 858         const char *errstr;
 859
 860         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 861                 return;
 862
 863         /* Special case: if the error is EROFS, and we're not already
 864          * inside a transaction, then there's really no point in logging
 865          * an error. */
 866         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 867                 return;
 868
 869         if (ext4_error_ratelimit(sb)) {
 870                 errstr = ext4_decode_error(sb, errno, nbuf);
 871                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 872                        sb->s_id, function, line, errstr);
 873         }
 874
 875         save_error_info(sb, -errno, 0, 0, function, line);
 876         ext4_handle_error(sb);
 877 }
 878
 879 /*
 880  * ext4_abort is a much stronger failure handler than ext4_error.  The
 881  * abort function may be used to deal with unrecoverable failures such
 882  * as journal IO errors or ENOMEM at a critical moment in log management.
 883  *
 884  * We unconditionally force the filesystem into an ABORT|READONLY state,
 885  * unless the error response on the fs has been set to panic in which
 886  * case we take the easy way out and panic immediately.
 887  */
 888
 889 void __ext4_abort(struct super_block *sb, const char *function,
 890                   unsigned int line, int error, const char *fmt, ...)
 891 {
 892         struct va_format vaf;
 893         va_list args;
 894
 895         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 896                 return;
 897
 898         save_error_info(sb, error, 0, 0, function, line);
 899         va_start(args, fmt);
 900         vaf.fmt = fmt;
 901         vaf.va = &args;
 902         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 903                sb->s_id, function, line, &vaf);
 904         va_end(args);
 905
 906         if (sb_rdonly(sb) == 0) {
 907                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 908                 if (EXT4_SB(sb)->s_journal)
 909                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 910
 911                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 912                 /*
 913                  * Make sure updated value of ->s_mount_flags will be visible
 914                  * before ->s_flags update
 915                  */
 916                 smp_wmb();
 917                 sb->s_flags |= SB_RDONLY;
 918         }
 919         if (test_opt(sb, ERRORS_PANIC) && !system_going_down())
 920                 panic("EXT4-fs panic from previous error\n");
 921 }
 922
 923 void __ext4_msg(struct super_block *sb,
 924                 const char *prefix, const char *fmt, ...)
 925 {
 926         struct va_format vaf;
 927         va_list args;
 928
 929         atomic_inc(&EXT4_SB(sb)->s_msg_count);
 930         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 931                 return;
 932
 933         va_start(args, fmt);
 934         vaf.fmt = fmt;
 935         vaf.va = &args;
 936         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 937         va_end(args);
 938 }
 939
 940 static int ext4_warning_ratelimit(struct super_block *sb)
 941 {
 942         atomic_inc(&EXT4_SB(sb)->s_warning_count);
 943         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
 944                             "EXT4-fs warning");
 945 }
 946
 947 void __ext4_warning(struct super_block *sb, const char *function,
 948                     unsigned int line, const char *fmt, ...)
 949 {
 950         struct va_format vaf;
 951         va_list args;
 952
 953         if (!ext4_warning_ratelimit(sb))
 954                 return;
 955
 956         va_start(args, fmt);
 957         vaf.fmt = fmt;
 958         vaf.va = &args;
 959         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 960                sb->s_id, function, line, &vaf);
 961         va_end(args);
 962 }
 963
 964 void __ext4_warning_inode(const struct inode *inode, const char *function,
 965                           unsigned int line, const char *fmt, ...)
 966 {
 967         struct va_format vaf;
 968         va_list args;
 969
 970         if (!ext4_warning_ratelimit(inode->i_sb))
 971                 return;
 972
 973         va_start(args, fmt);
 974         vaf.fmt = fmt;
 975         vaf.va = &args;
 976         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 977                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 978                function, line, inode->i_ino, current->comm, &vaf);
 979         va_end(args);
 980 }
 981
 982 void __ext4_grp_locked_error(const char *function, unsigned int line,
 983                              struct super_block *sb, ext4_group_t grp,
 984                              unsigned long ino, ext4_fsblk_t block,
 985                              const char *fmt, ...)
 986 __releases(bitlock)
 987 __acquires(bitlock)
 988 {
 989         struct va_format vaf;
 990         va_list args;
 991
 992         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 993                 return;
 994
 995         trace_ext4_error(sb, function, line);
 996         __save_error_info(sb, EFSCORRUPTED, ino, block, function, line);
 997
 998         if (ext4_error_ratelimit(sb)) {
 999                 va_start(args, fmt);
1000                 vaf.fmt = fmt;
1001                 vaf.va = &args;
1002                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
1003                        sb->s_id, function, line, grp);
1004                 if (ino)
1005                         printk(KERN_CONT "inode %lu: ", ino);
1006                 if (block)
1007                         printk(KERN_CONT "block %llu:",
1008                                (unsigned long long) block);
1009                 printk(KERN_CONT "%pV\n", &vaf);
1010                 va_end(args);
1011         }
1012
1013         if (test_opt(sb, WARN_ON_ERROR))
1014                 WARN_ON_ONCE(1);
1015
1016         if (test_opt(sb, ERRORS_CONT)) {
1017                 ext4_commit_super(sb, 0);
1018                 return;
1019         }
1020
1021         ext4_unlock_group(sb, grp);
1022         ext4_commit_super(sb, 1);
1023         ext4_handle_error(sb);
1024         /*
1025          * We only get here in the ERRORS_RO case; relocking the group
1026          * may be dangerous, but nothing bad will happen since the
1027          * filesystem will have already been marked read/only and the
1028          * journal has been aborted.  We return 1 as a hint to callers
1029          * who might what to use the return value from
1030          * ext4_grp_locked_error() to distinguish between the
1031          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1032          * aggressively from the ext4 function in question, with a
1033          * more appropriate error code.
1034          */
1035         ext4_lock_group(sb, grp);
1036         return;
1037 }
1038
1039 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1040                                      ext4_group_t group,
1041                                      unsigned int flags)
1042 {
1043         struct ext4_sb_info *sbi = EXT4_SB(sb);
1044         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1045         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1046         int ret;
1047
1048         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1049                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1050                                             &grp->bb_state);
1051                 if (!ret)
1052                         percpu_counter_sub(&sbi->s_freeclusters_counter,
1053                                            grp->bb_free);
1054         }
1055
1056         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1057                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1058                                             &grp->bb_state);
1059                 if (!ret && gdp) {
1060                         int count;
1061
1062                         count = ext4_free_inodes_count(sb, gdp);
1063                         percpu_counter_sub(&sbi->s_freeinodes_counter,
1064                                            count);
1065                 }
1066         }
1067 }
1068
1069 void ext4_update_dynamic_rev(struct super_block *sb)
1070 {
1071         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1072
1073         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1074                 return;
1075
1076         ext4_warning(sb,
1077                      "updating to rev %d because of new feature flag, "
1078                      "running e2fsck is recommended",
1079                      EXT4_DYNAMIC_REV);
1080
1081         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1082         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1083         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1084         /* leave es->s_feature_*compat flags alone */
1085         /* es->s_uuid will be set by e2fsck if empty */
1086
1087         /*
1088          * The rest of the superblock fields should be zero, and if not it
1089          * means they are likely already in use, so leave them alone.  We
1090          * can leave it up to e2fsck to clean up any inconsistencies there.
1091          */
1092 }
1093
1094 /*
1095  * Open the external journal device
1096  */
1097 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
1098 {
1099         struct block_device *bdev;
1100
1101         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
1102         if (IS_ERR(bdev))
1103                 goto fail;
1104         return bdev;
1105
1106 fail:
1107         ext4_msg(sb, KERN_ERR,
1108                  "failed to open journal device unknown-block(%u,%u) %ld",
1109                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
1110         return NULL;
1111 }
1112
1113 /*
1114  * Release the journal device
1115  */
1116 static void ext4_blkdev_put(struct block_device *bdev)
1117 {
1118         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1119 }
1120
1121 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
1122 {
1123         struct block_device *bdev;
1124         bdev = sbi->s_journal_bdev;
1125         if (bdev) {
1126                 ext4_blkdev_put(bdev);
1127                 sbi->s_journal_bdev = NULL;
1128         }
1129 }
1130
1131 static inline struct inode *orphan_list_entry(struct list_head *l)
1132 {
1133         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1134 }
1135
1136 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1137 {
1138         struct list_head *l;
1139
1140         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1141                  le32_to_cpu(sbi->s_es->s_last_orphan));
1142
1143         printk(KERN_ERR "sb_info orphan list:\n");
1144         list_for_each(l, &sbi->s_orphan) {
1145                 struct inode *inode = orphan_list_entry(l);
1146                 printk(KERN_ERR "  "
1147                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1148                        inode->i_sb->s_id, inode->i_ino, inode,
1149                        inode->i_mode, inode->i_nlink,
1150                        NEXT_ORPHAN(inode));
1151         }
1152 }
1153
1154 #ifdef CONFIG_QUOTA
1155 static int ext4_quota_off(struct super_block *sb, int type);
1156
1157 static inline void ext4_quota_off_umount(struct super_block *sb)
1158 {
1159         int type;
1160
1161         /* Use our quota_off function to clear inode flags etc. */
1162         for (type = 0; type < EXT4_MAXQUOTAS; type++)
1163                 ext4_quota_off(sb, type);
1164 }
1165
1166 /*
1167  * This is a helper function which is used in the mount/remount
1168  * codepaths (which holds s_umount) to fetch the quota file name.
1169  */
1170 static inline char *get_qf_name(struct super_block *sb,
1171                                 struct ext4_sb_info *sbi,
1172                                 int type)
1173 {
1174         return rcu_dereference_protected(sbi->s_qf_names[type],
1175                                          lockdep_is_held(&sb->s_umount));
1176 }
1177 #else
1178 static inline void ext4_quota_off_umount(struct super_block *sb)
1179 {
1180 }
1181 #endif
1182
1183 static void ext4_put_super(struct super_block *sb)
1184 {
1185         struct ext4_sb_info *sbi = EXT4_SB(sb);
1186         struct ext4_super_block *es = sbi->s_es;
1187         struct buffer_head **group_desc;
1188         struct flex_groups **flex_groups;
1189         int aborted = 0;
1190         int i, err;
1191
1192         ext4_unregister_li_request(sb);
1193         ext4_quota_off_umount(sb);
1194
1195         destroy_workqueue(sbi->rsv_conversion_wq);
1196
1197         /*
1198          * Unregister sysfs before destroying jbd2 journal.
1199          * Since we could still access attr_journal_task attribute via sysfs
1200          * path which could have sbi->s_journal->j_task as NULL
1201          */
1202         ext4_unregister_sysfs(sb);
1203
1204         if (sbi->s_journal) {
1205                 aborted = is_journal_aborted(sbi->s_journal);
1206                 err = jbd2_journal_destroy(sbi->s_journal);
1207                 sbi->s_journal = NULL;
1208                 if ((err < 0) && !aborted) {
1209                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1210                 }
1211         }
1212
1213         ext4_es_unregister_shrinker(sbi);
1214         del_timer_sync(&sbi->s_err_report);
1215         ext4_release_system_zone(sb);
1216         ext4_mb_release(sb);
1217         ext4_ext_release(sb);
1218
1219         if (!sb_rdonly(sb) && !aborted) {
1220                 ext4_clear_feature_journal_needs_recovery(sb);
1221                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1222         }
1223         if (!sb_rdonly(sb))
1224                 ext4_commit_super(sb, 1);
1225
1226         rcu_read_lock();
1227         group_desc = rcu_dereference(sbi->s_group_desc);
1228         for (i = 0; i < sbi->s_gdb_count; i++)
1229                 brelse(group_desc[i]);
1230         kvfree(group_desc);
1231         flex_groups = rcu_dereference(sbi->s_flex_groups);
1232         if (flex_groups) {
1233                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1234                         kvfree(flex_groups[i]);
1235                 kvfree(flex_groups);
1236         }
1237         rcu_read_unlock();
1238         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1239         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1240         percpu_counter_destroy(&sbi->s_dirs_counter);
1241         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1242         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1243 #ifdef CONFIG_QUOTA
1244         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1245                 kfree(get_qf_name(sb, sbi, i));
1246 #endif
1247
1248         /* Debugging code just in case the in-memory inode orphan list
1249          * isn't empty.  The on-disk one can be non-empty if we've
1250          * detected an error and taken the fs readonly, but the
1251          * in-memory list had better be clean by this point. */
1252         if (!list_empty(&sbi->s_orphan))
1253                 dump_orphan_list(sb, sbi);
1254         J_ASSERT(list_empty(&sbi->s_orphan));
1255
1256         sync_blockdev(sb->s_bdev);
1257         invalidate_bdev(sb->s_bdev);
1258         if (sbi->s_journal_bdev && sbi->s_journal_bdev != sb->s_bdev) {
1259                 /*
1260                  * Invalidate the journal device's buffers.  We don't want them
1261                  * floating about in memory - the physical journal device may
1262                  * hotswapped, and it breaks the `ro-after' testing code.
1263                  */
1264                 sync_blockdev(sbi->s_journal_bdev);
1265                 invalidate_bdev(sbi->s_journal_bdev);
1266                 ext4_blkdev_remove(sbi);
1267         }
1268
1269         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1270         sbi->s_ea_inode_cache = NULL;
1271
1272         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1273         sbi->s_ea_block_cache = NULL;
1274
1275         if (sbi->s_mmp_tsk)
1276                 kthread_stop(sbi->s_mmp_tsk);
1277         brelse(sbi->s_sbh);
1278         sb->s_fs_info = NULL;
1279         /*
1280          * Now that we are completely done shutting down the
1281          * superblock, we need to actually destroy the kobject.
1282          */
1283         kobject_put(&sbi->s_kobj);
1284         wait_for_completion(&sbi->s_kobj_unregister);
1285         if (sbi->s_chksum_driver)
1286                 crypto_free_shash(sbi->s_chksum_driver);
1287         kfree(sbi->s_blockgroup_lock);
1288         fs_put_dax(sbi->s_daxdev);
1289         fscrypt_free_dummy_context(&sbi->s_dummy_enc_ctx);
1290 #ifdef CONFIG_UNICODE
1291         utf8_unload(sbi->s_encoding);
1292 #endif
1293         kfree(sbi);
1294 }
1295
1296 static struct kmem_cache *ext4_inode_cachep;
1297
1298 /*
1299  * Called inside transaction, so use GFP_NOFS
1300  */
1301 static struct inode *ext4_alloc_inode(struct super_block *sb)
1302 {
1303         struct ext4_inode_info *ei;
1304
1305         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1306         if (!ei)
1307                 return NULL;
1308
1309         inode_set_iversion(&ei->vfs_inode, 1);
1310         spin_lock_init(&ei->i_raw_lock);
1311         INIT_LIST_HEAD(&ei->i_prealloc_list);
1312         atomic_set(&ei->i_prealloc_active, 0);
1313         spin_lock_init(&ei->i_prealloc_lock);
1314         ext4_es_init_tree(&ei->i_es_tree);
1315         rwlock_init(&ei->i_es_lock);
1316         INIT_LIST_HEAD(&ei->i_es_list);
1317         ei->i_es_all_nr = 0;
1318         ei->i_es_shk_nr = 0;
1319         ei->i_es_shrink_lblk = 0;
1320         ei->i_reserved_data_blocks = 0;
1321         spin_lock_init(&(ei->i_block_reservation_lock));
1322         ext4_init_pending_tree(&ei->i_pending_tree);
1323 #ifdef CONFIG_QUOTA
1324         ei->i_reserved_quota = 0;
1325         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1326 #endif
1327         ei->jinode = NULL;
1328         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1329         spin_lock_init(&ei->i_completed_io_lock);
1330         ei->i_sync_tid = 0;
1331         ei->i_datasync_tid = 0;
1332         atomic_set(&ei->i_unwritten, 0);
1333         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1334         return &ei->vfs_inode;
1335 }
1336
1337 static int ext4_drop_inode(struct inode *inode)
1338 {
1339         int drop = generic_drop_inode(inode);
1340
1341         if (!drop)
1342                 drop = fscrypt_drop_inode(inode);
1343
1344         trace_ext4_drop_inode(inode, drop);
1345         return drop;
1346 }
1347
1348 static void ext4_free_in_core_inode(struct inode *inode)
1349 {
1350         fscrypt_free_inode(inode);
1351         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1352 }
1353
1354 static void ext4_destroy_inode(struct inode *inode)
1355 {
1356         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1357                 ext4_msg(inode->i_sb, KERN_ERR,
1358                          "Inode %lu (%p): orphan list check failed!",
1359                          inode->i_ino, EXT4_I(inode));
1360                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1361                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1362                                 true);
1363                 dump_stack();
1364         }
1365 }
1366
1367 static void init_once(void *foo)
1368 {
1369         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1370
1371         INIT_LIST_HEAD(&ei->i_orphan);
1372         init_rwsem(&ei->xattr_sem);
1373         init_rwsem(&ei->i_data_sem);
1374         init_rwsem(&ei->i_mmap_sem);
1375         inode_init_once(&ei->vfs_inode);
1376 }
1377
1378 static int __init init_inodecache(void)
1379 {
1380         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1381                                 sizeof(struct ext4_inode_info), 0,
1382                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1383                                         SLAB_ACCOUNT),
1384                                 offsetof(struct ext4_inode_info, i_data),
1385                                 sizeof_field(struct ext4_inode_info, i_data),
1386                                 init_once);
1387         if (ext4_inode_cachep == NULL)
1388                 return -ENOMEM;
1389         return 0;
1390 }
1391
1392 static void destroy_inodecache(void)
1393 {
1394         /*
1395          * Make sure all delayed rcu free inodes are flushed before we
1396          * destroy cache.
1397          */
1398         rcu_barrier();
1399         kmem_cache_destroy(ext4_inode_cachep);
1400 }
1401
1402 void ext4_clear_inode(struct inode *inode)
1403 {
1404         invalidate_inode_buffers(inode);
1405         clear_inode(inode);
1406         ext4_discard_preallocations(inode, 0);
1407         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1408         dquot_drop(inode);
1409         if (EXT4_I(inode)->jinode) {
1410                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1411                                                EXT4_I(inode)->jinode);
1412                 jbd2_free_inode(EXT4_I(inode)->jinode);
1413                 EXT4_I(inode)->jinode = NULL;
1414         }
1415         fscrypt_put_encryption_info(inode);
1416         fsverity_cleanup_inode(inode);
1417 }
1418
1419 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1420                                         u64 ino, u32 generation)
1421 {
1422         struct inode *inode;
1423
1424         /*
1425          * Currently we don't know the generation for parent directory, so
1426          * a generation of 0 means "accept any"
1427          */
1428         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1429         if (IS_ERR(inode))
1430                 return ERR_CAST(inode);
1431         if (generation && inode->i_generation != generation) {
1432                 iput(inode);
1433                 return ERR_PTR(-ESTALE);
1434         }
1435
1436         return inode;
1437 }
1438
1439 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1440                                         int fh_len, int fh_type)
1441 {
1442         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1443                                     ext4_nfs_get_inode);
1444 }
1445
1446 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1447                                         int fh_len, int fh_type)
1448 {
1449         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1450                                     ext4_nfs_get_inode);
1451 }
1452
1453 static int ext4_nfs_commit_metadata(struct inode *inode)
1454 {
1455         struct writeback_control wbc = {
1456                 .sync_mode = WB_SYNC_ALL
1457         };
1458
1459         trace_ext4_nfs_commit_metadata(inode);
1460         return ext4_write_inode(inode, &wbc);
1461 }
1462
1463 /*
1464  * Try to release metadata pages (indirect blocks, directories) which are
1465  * mapped via the block device.  Since these pages could have journal heads
1466  * which would prevent try_to_free_buffers() from freeing them, we must use
1467  * jbd2 layer's try_to_free_buffers() function to release them.
1468  */
1469 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1470                                  gfp_t wait)
1471 {
1472         journal_t *journal = EXT4_SB(sb)->s_journal;
1473
1474         WARN_ON(PageChecked(page));
1475         if (!page_has_buffers(page))
1476                 return 0;
1477         if (journal)
1478                 return jbd2_journal_try_to_free_buffers(journal, page);
1479
1480         return try_to_free_buffers(page);
1481 }
1482
1483 #ifdef CONFIG_FS_ENCRYPTION
1484 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1485 {
1486         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1487                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1488 }
1489
1490 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1491                                                         void *fs_data)
1492 {
1493         handle_t *handle = fs_data;
1494         int res, res2, credits, retries = 0;
1495
1496         /*
1497          * Encrypting the root directory is not allowed because e2fsck expects
1498          * lost+found to exist and be unencrypted, and encrypting the root
1499          * directory would imply encrypting the lost+found directory as well as
1500          * the filename "lost+found" itself.
1501          */
1502         if (inode->i_ino == EXT4_ROOT_INO)
1503                 return -EPERM;
1504
1505         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1506                 return -EINVAL;
1507
1508         if (ext4_test_inode_flag(inode, EXT4_INODE_DAX))
1509                 return -EOPNOTSUPP;
1510
1511         res = ext4_convert_inline_data(inode);
1512         if (res)
1513                 return res;
1514
1515         /*
1516          * If a journal handle was specified, then the encryption context is
1517          * being set on a new inode via inheritance and is part of a larger
1518          * transaction to create the inode.  Otherwise the encryption context is
1519          * being set on an existing inode in its own transaction.  Only in the
1520          * latter case should the "retry on ENOSPC" logic be used.
1521          */
1522
1523         if (handle) {
1524                 res = ext4_xattr_set_handle(handle, inode,
1525                                             EXT4_XATTR_INDEX_ENCRYPTION,
1526                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1527                                             ctx, len, 0);
1528                 if (!res) {
1529                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1530                         ext4_clear_inode_state(inode,
1531                                         EXT4_STATE_MAY_INLINE_DATA);
1532                         /*
1533                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1534                          * S_DAX may be disabled
1535                          */
1536                         ext4_set_inode_flags(inode, false);
1537                 }
1538                 return res;
1539         }
1540
1541         res = dquot_initialize(inode);
1542         if (res)
1543                 return res;
1544 retry:
1545         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1546                                      &credits);
1547         if (res)
1548                 return res;
1549
1550         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1551         if (IS_ERR(handle))
1552                 return PTR_ERR(handle);
1553
1554         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1555                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1556                                     ctx, len, 0);
1557         if (!res) {
1558                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1559                 /*
1560                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1561                  * S_DAX may be disabled
1562                  */
1563                 ext4_set_inode_flags(inode, false);
1564                 res = ext4_mark_inode_dirty(handle, inode);
1565                 if (res)
1566                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1567         }
1568         res2 = ext4_journal_stop(handle);
1569
1570         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1571                 goto retry;
1572         if (!res)
1573                 res = res2;
1574         return res;
1575 }
1576
1577 static const union fscrypt_context *
1578 ext4_get_dummy_context(struct super_block *sb)
1579 {
1580         return EXT4_SB(sb)->s_dummy_enc_ctx.ctx;
1581 }
1582
1583 static bool ext4_has_stable_inodes(struct super_block *sb)
1584 {
1585         return ext4_has_feature_stable_inodes(sb);
1586 }
1587
1588 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1589                                        int *ino_bits_ret, int *lblk_bits_ret)
1590 {
1591         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1592         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1593 }
1594
1595 static const struct fscrypt_operations ext4_cryptops = {
1596         .key_prefix             = "ext4:",
1597         .get_context            = ext4_get_context,
1598         .set_context            = ext4_set_context,
1599         .get_dummy_context      = ext4_get_dummy_context,
1600         .empty_dir              = ext4_empty_dir,
1601         .max_namelen            = EXT4_NAME_LEN,
1602         .has_stable_inodes      = ext4_has_stable_inodes,
1603         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1604 };
1605 #endif
1606
1607 #ifdef CONFIG_QUOTA
1608 static const char * const quotatypes[] = INITQFNAMES;
1609 #define QTYPE2NAME(t) (quotatypes[t])
1610
1611 static int ext4_write_dquot(struct dquot *dquot);
1612 static int ext4_acquire_dquot(struct dquot *dquot);
1613 static int ext4_release_dquot(struct dquot *dquot);
1614 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1615 static int ext4_write_info(struct super_block *sb, int type);
1616 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1617                          const struct path *path);
1618 static int ext4_quota_on_mount(struct super_block *sb, int type);
1619 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1620                                size_t len, loff_t off);
1621 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1622                                 const char *data, size_t len, loff_t off);
1623 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1624                              unsigned int flags);
1625 static int ext4_enable_quotas(struct super_block *sb);
1626
1627 static struct dquot **ext4_get_dquots(struct inode *inode)
1628 {
1629         return EXT4_I(inode)->i_dquot;
1630 }
1631
1632 static const struct dquot_operations ext4_quota_operations = {
1633         .get_reserved_space     = ext4_get_reserved_space,
1634         .write_dquot            = ext4_write_dquot,
1635         .acquire_dquot          = ext4_acquire_dquot,
1636         .release_dquot          = ext4_release_dquot,
1637         .mark_dirty             = ext4_mark_dquot_dirty,
1638         .write_info             = ext4_write_info,
1639         .alloc_dquot            = dquot_alloc,
1640         .destroy_dquot          = dquot_destroy,
1641         .get_projid             = ext4_get_projid,
1642         .get_inode_usage        = ext4_get_inode_usage,
1643         .get_next_id            = dquot_get_next_id,
1644 };
1645
1646 static const struct quotactl_ops ext4_qctl_operations = {
1647         .quota_on       = ext4_quota_on,
1648         .quota_off      = ext4_quota_off,
1649         .quota_sync     = dquot_quota_sync,
1650         .get_state      = dquot_get_state,
1651         .set_info       = dquot_set_dqinfo,
1652         .get_dqblk      = dquot_get_dqblk,
1653         .set_dqblk      = dquot_set_dqblk,
1654         .get_nextdqblk  = dquot_get_next_dqblk,
1655 };
1656 #endif
1657
1658 static const struct super_operations ext4_sops = {
1659         .alloc_inode    = ext4_alloc_inode,
1660         .free_inode     = ext4_free_in_core_inode,
1661         .destroy_inode  = ext4_destroy_inode,
1662         .write_inode    = ext4_write_inode,
1663         .dirty_inode    = ext4_dirty_inode,
1664         .drop_inode     = ext4_drop_inode,
1665         .evict_inode    = ext4_evict_inode,
1666         .put_super      = ext4_put_super,
1667         .sync_fs        = ext4_sync_fs,
1668         .freeze_fs      = ext4_freeze,
1669         .unfreeze_fs    = ext4_unfreeze,
1670         .statfs         = ext4_statfs,
1671         .remount_fs     = ext4_remount,
1672         .show_options   = ext4_show_options,
1673 #ifdef CONFIG_QUOTA
1674         .quota_read     = ext4_quota_read,
1675         .quota_write    = ext4_quota_write,
1676         .get_dquots     = ext4_get_dquots,
1677 #endif
1678         .bdev_try_to_free_page = bdev_try_to_free_page,
1679 };
1680
1681 static const struct export_operations ext4_export_ops = {
1682         .fh_to_dentry = ext4_fh_to_dentry,
1683         .fh_to_parent = ext4_fh_to_parent,
1684         .get_parent = ext4_get_parent,
1685         .commit_metadata = ext4_nfs_commit_metadata,
1686 };
1687
1688 enum {
1689         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1690         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1691         Opt_nouid32, Opt_debug, Opt_removed,
1692         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1693         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1694         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1695         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1696         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1697         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1698         Opt_inlinecrypt,
1699         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1700         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1701         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1702         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
1703         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1704         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1705         Opt_nowarn_on_error, Opt_mblk_io_submit,
1706         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1707         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1708         Opt_inode_readahead_blks, Opt_journal_ioprio,
1709         Opt_dioread_nolock, Opt_dioread_lock,
1710         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1711         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1712         Opt_prefetch_block_bitmaps, Opt_no_fc,
1713 };
1714
1715 static const match_table_t tokens = {
1716         {Opt_bsd_df, "bsddf"},
1717         {Opt_minix_df, "minixdf"},
1718         {Opt_grpid, "grpid"},
1719         {Opt_grpid, "bsdgroups"},
1720         {Opt_nogrpid, "nogrpid"},
1721         {Opt_nogrpid, "sysvgroups"},
1722         {Opt_resgid, "resgid=%u"},
1723         {Opt_resuid, "resuid=%u"},
1724         {Opt_sb, "sb=%u"},
1725         {Opt_err_cont, "errors=continue"},
1726         {Opt_err_panic, "errors=panic"},
1727         {Opt_err_ro, "errors=remount-ro"},
1728         {Opt_nouid32, "nouid32"},
1729         {Opt_debug, "debug"},
1730         {Opt_removed, "oldalloc"},
1731         {Opt_removed, "orlov"},
1732         {Opt_user_xattr, "user_xattr"},
1733         {Opt_nouser_xattr, "nouser_xattr"},
1734         {Opt_acl, "acl"},
1735         {Opt_noacl, "noacl"},
1736         {Opt_noload, "norecovery"},
1737         {Opt_noload, "noload"},
1738         {Opt_removed, "nobh"},
1739         {Opt_removed, "bh"},
1740         {Opt_commit, "commit=%u"},
1741         {Opt_min_batch_time, "min_batch_time=%u"},
1742         {Opt_max_batch_time, "max_batch_time=%u"},
1743         {Opt_journal_dev, "journal_dev=%u"},
1744         {Opt_journal_path, "journal_path=%s"},
1745         {Opt_journal_checksum, "journal_checksum"},
1746         {Opt_nojournal_checksum, "nojournal_checksum"},
1747         {Opt_journal_async_commit, "journal_async_commit"},
1748         {Opt_abort, "abort"},
1749         {Opt_data_journal, "data=journal"},
1750         {Opt_data_ordered, "data=ordered"},
1751         {Opt_data_writeback, "data=writeback"},
1752         {Opt_data_err_abort, "data_err=abort"},
1753         {Opt_data_err_ignore, "data_err=ignore"},
1754         {Opt_offusrjquota, "usrjquota="},
1755         {Opt_usrjquota, "usrjquota=%s"},
1756         {Opt_offgrpjquota, "grpjquota="},
1757         {Opt_grpjquota, "grpjquota=%s"},
1758         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1759         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1760         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1761         {Opt_grpquota, "grpquota"},
1762         {Opt_noquota, "noquota"},
1763         {Opt_quota, "quota"},
1764         {Opt_usrquota, "usrquota"},
1765         {Opt_prjquota, "prjquota"},
1766         {Opt_barrier, "barrier=%u"},
1767         {Opt_barrier, "barrier"},
1768         {Opt_nobarrier, "nobarrier"},
1769         {Opt_i_version, "i_version"},
1770         {Opt_dax, "dax"},
1771         {Opt_dax_always, "dax=always"},
1772         {Opt_dax_inode, "dax=inode"},
1773         {Opt_dax_never, "dax=never"},
1774         {Opt_stripe, "stripe=%u"},
1775         {Opt_delalloc, "delalloc"},
1776         {Opt_warn_on_error, "warn_on_error"},
1777         {Opt_nowarn_on_error, "nowarn_on_error"},
1778         {Opt_lazytime, "lazytime"},
1779         {Opt_nolazytime, "nolazytime"},
1780         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1781         {Opt_nodelalloc, "nodelalloc"},
1782         {Opt_removed, "mblk_io_submit"},
1783         {Opt_removed, "nomblk_io_submit"},
1784         {Opt_block_validity, "block_validity"},
1785         {Opt_noblock_validity, "noblock_validity"},
1786         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1787         {Opt_journal_ioprio, "journal_ioprio=%u"},
1788         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1789         {Opt_auto_da_alloc, "auto_da_alloc"},
1790         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1791         {Opt_dioread_nolock, "dioread_nolock"},
1792         {Opt_dioread_lock, "nodioread_nolock"},
1793         {Opt_dioread_lock, "dioread_lock"},
1794         {Opt_discard, "discard"},
1795         {Opt_nodiscard, "nodiscard"},
1796         {Opt_init_itable, "init_itable=%u"},
1797         {Opt_init_itable, "init_itable"},
1798         {Opt_noinit_itable, "noinit_itable"},
1799         {Opt_no_fc, "no_fc"},
1800         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1801         {Opt_test_dummy_encryption, "test_dummy_encryption=%s"},
1802         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1803         {Opt_inlinecrypt, "inlinecrypt"},
1804         {Opt_nombcache, "nombcache"},
1805         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1806         {Opt_prefetch_block_bitmaps, "prefetch_block_bitmaps"},
1807         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1808         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1809         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1810         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1811         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1812         {Opt_err, NULL},
1813 };
1814
1815 static ext4_fsblk_t get_sb_block(void **data)
1816 {
1817         ext4_fsblk_t    sb_block;
1818         char            *options = (char *) *data;
1819
1820         if (!options || strncmp(options, "sb=", 3) != 0)
1821                 return 1;       /* Default location */
1822
1823         options += 3;
1824         /* TODO: use simple_strtoll with >32bit ext4 */
1825         sb_block = simple_strtoul(options, &options, 0);
1826         if (*options && *options != ',') {
1827                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1828                        (char *) *data);
1829                 return 1;
1830         }
1831         if (*options == ',')
1832                 options++;
1833         *data = (void *) options;
1834
1835         return sb_block;
1836 }
1837
1838 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1839 static const char deprecated_msg[] =
1840         "Mount option \"%s\" will be removed by %s\n"
1841         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1842
1843 #ifdef CONFIG_QUOTA
1844 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1845 {
1846         struct ext4_sb_info *sbi = EXT4_SB(sb);
1847         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1848         int ret = -1;
1849
1850         if (sb_any_quota_loaded(sb) && !old_qname) {
1851                 ext4_msg(sb, KERN_ERR,
1852                         "Cannot change journaled "
1853                         "quota options when quota turned on");
1854                 return -1;
1855         }
1856         if (ext4_has_feature_quota(sb)) {
1857                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1858                          "ignored when QUOTA feature is enabled");
1859                 return 1;
1860         }
1861         qname = match_strdup(args);
1862         if (!qname) {
1863                 ext4_msg(sb, KERN_ERR,
1864                         "Not enough memory for storing quotafile name");
1865                 return -1;
1866         }
1867         if (old_qname) {
1868                 if (strcmp(old_qname, qname) == 0)
1869                         ret = 1;
1870                 else
1871                         ext4_msg(sb, KERN_ERR,
1872                                  "%s quota file already specified",
1873                                  QTYPE2NAME(qtype));
1874                 goto errout;
1875         }
1876         if (strchr(qname, '/')) {
1877                 ext4_msg(sb, KERN_ERR,
1878                         "quotafile must be on filesystem root");
1879                 goto errout;
1880         }
1881         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1882         set_opt(sb, QUOTA);
1883         return 1;
1884 errout:
1885         kfree(qname);
1886         return ret;
1887 }
1888
1889 static int clear_qf_name(struct super_block *sb, int qtype)
1890 {
1891
1892         struct ext4_sb_info *sbi = EXT4_SB(sb);
1893         char *old_qname = get_qf_name(sb, sbi, qtype);
1894
1895         if (sb_any_quota_loaded(sb) && old_qname) {
1896                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1897                         " when quota turned on");
1898                 return -1;
1899         }
1900         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1901         synchronize_rcu();
1902         kfree(old_qname);
1903         return 1;
1904 }
1905 #endif
1906
1907 #define MOPT_SET        0x0001
1908 #define MOPT_CLEAR      0x0002
1909 #define MOPT_NOSUPPORT  0x0004
1910 #define MOPT_EXPLICIT   0x0008
1911 #define MOPT_CLEAR_ERR  0x0010
1912 #define MOPT_GTE0       0x0020
1913 #ifdef CONFIG_QUOTA
1914 #define MOPT_Q          0
1915 #define MOPT_QFMT       0x0040
1916 #else
1917 #define MOPT_Q          MOPT_NOSUPPORT
1918 #define MOPT_QFMT       MOPT_NOSUPPORT
1919 #endif
1920 #define MOPT_DATAJ      0x0080
1921 #define MOPT_NO_EXT2    0x0100
1922 #define MOPT_NO_EXT3    0x0200
1923 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1924 #define MOPT_STRING     0x0400
1925 #define MOPT_SKIP       0x0800
1926 #define MOPT_2          0x1000
1927
1928 static const struct mount_opts {
1929         int     token;
1930         int     mount_opt;
1931         int     flags;
1932 } ext4_mount_opts[] = {
1933         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1934         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1935         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1936         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1937         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1938         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1939         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1940          MOPT_EXT4_ONLY | MOPT_SET},
1941         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1942          MOPT_EXT4_ONLY | MOPT_CLEAR},
1943         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1944         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1945         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1946          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1947         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1948          MOPT_EXT4_ONLY | MOPT_CLEAR},
1949         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1950         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1951         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1952          MOPT_EXT4_ONLY | MOPT_CLEAR},
1953         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1954          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1955         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1956                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1957          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1958         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1959         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1960         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1961         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1962         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1963          MOPT_NO_EXT2},
1964         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1965          MOPT_NO_EXT2},
1966         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1967         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1968         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1969         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1970         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1971         {Opt_commit, 0, MOPT_GTE0},
1972         {Opt_max_batch_time, 0, MOPT_GTE0},
1973         {Opt_min_batch_time, 0, MOPT_GTE0},
1974         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1975         {Opt_init_itable, 0, MOPT_GTE0},
1976         {Opt_dax, EXT4_MOUNT_DAX_ALWAYS, MOPT_SET | MOPT_SKIP},
1977         {Opt_dax_always, EXT4_MOUNT_DAX_ALWAYS,
1978                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1979         {Opt_dax_inode, EXT4_MOUNT2_DAX_INODE,
1980                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1981         {Opt_dax_never, EXT4_MOUNT2_DAX_NEVER,
1982                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1983         {Opt_stripe, 0, MOPT_GTE0},
1984         {Opt_resuid, 0, MOPT_GTE0},
1985         {Opt_resgid, 0, MOPT_GTE0},
1986         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1987         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1988         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1989         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1990         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1991         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1992          MOPT_NO_EXT2 | MOPT_DATAJ},
1993         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1994         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1995 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1996         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1997         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1998 #else
1999         {Opt_acl, 0, MOPT_NOSUPPORT},
2000         {Opt_noacl, 0, MOPT_NOSUPPORT},
2001 #endif
2002         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
2003         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
2004         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
2005         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
2006         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
2007                                                         MOPT_SET | MOPT_Q},
2008         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
2009                                                         MOPT_SET | MOPT_Q},
2010         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
2011                                                         MOPT_SET | MOPT_Q},
2012         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2013                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
2014                                                         MOPT_CLEAR | MOPT_Q},
2015         {Opt_usrjquota, 0, MOPT_Q},
2016         {Opt_grpjquota, 0, MOPT_Q},
2017         {Opt_offusrjquota, 0, MOPT_Q},
2018         {Opt_offgrpjquota, 0, MOPT_Q},
2019         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
2020         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
2021         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
2022         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
2023         {Opt_test_dummy_encryption, 0, MOPT_STRING},
2024         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
2025         {Opt_prefetch_block_bitmaps, EXT4_MOUNT_PREFETCH_BLOCK_BITMAPS,
2026          MOPT_SET},
2027         {Opt_no_fc, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
2028          MOPT_CLEAR | MOPT_2 | MOPT_EXT4_ONLY},
2029         {Opt_err, 0, 0}
2030 };
2031
2032 #ifdef CONFIG_UNICODE
2033 static const struct ext4_sb_encodings {
2034         __u16 magic;
2035         char *name;
2036         char *version;
2037 } ext4_sb_encoding_map[] = {
2038         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
2039 };
2040
2041 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
2042                                  const struct ext4_sb_encodings **encoding,
2043                                  __u16 *flags)
2044 {
2045         __u16 magic = le16_to_cpu(es->s_encoding);
2046         int i;
2047
2048         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
2049                 if (magic == ext4_sb_encoding_map[i].magic)
2050                         break;
2051
2052         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
2053                 return -EINVAL;
2054
2055         *encoding = &ext4_sb_encoding_map[i];
2056         *flags = le16_to_cpu(es->s_encoding_flags);
2057
2058         return 0;
2059 }
2060 #endif
2061
2062 static int ext4_set_test_dummy_encryption(struct super_block *sb,
2063                                           const char *opt,
2064                                           const substring_t *arg,
2065                                           bool is_remount)
2066 {
2067 #ifdef CONFIG_FS_ENCRYPTION
2068         struct ext4_sb_info *sbi = EXT4_SB(sb);
2069         int err;
2070
2071         /*
2072          * This mount option is just for testing, and it's not worthwhile to
2073          * implement the extra complexity (e.g. RCU protection) that would be
2074          * needed to allow it to be set or changed during remount.  We do allow
2075          * it to be specified during remount, but only if there is no change.
2076          */
2077         if (is_remount && !sbi->s_dummy_enc_ctx.ctx) {
2078                 ext4_msg(sb, KERN_WARNING,
2079                          "Can't set test_dummy_encryption on remount");
2080                 return -1;
2081         }
2082         err = fscrypt_set_test_dummy_encryption(sb, arg, &sbi->s_dummy_enc_ctx);
2083         if (err) {
2084                 if (err == -EEXIST)
2085                         ext4_msg(sb, KERN_WARNING,
2086                                  "Can't change test_dummy_encryption on remount");
2087                 else if (err == -EINVAL)
2088                         ext4_msg(sb, KERN_WARNING,
2089                                  "Value of option \"%s\" is unrecognized", opt);
2090                 else
2091                         ext4_msg(sb, KERN_WARNING,
2092                                  "Error processing option \"%s\" [%d]",
2093                                  opt, err);
2094                 return -1;
2095         }
2096         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2097 #else
2098         ext4_msg(sb, KERN_WARNING,
2099                  "Test dummy encryption mount option ignored");
2100 #endif
2101         return 1;
2102 }
2103
2104 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
2105                             substring_t *args, unsigned long *journal_devnum,
2106                             unsigned int *journal_ioprio, int is_remount)
2107 {
2108         struct ext4_sb_info *sbi = EXT4_SB(sb);
2109         const struct mount_opts *m;
2110         kuid_t uid;
2111         kgid_t gid;
2112         int arg = 0;
2113
2114 #ifdef CONFIG_QUOTA
2115         if (token == Opt_usrjquota)
2116                 return set_qf_name(sb, USRQUOTA, &args[0]);
2117         else if (token == Opt_grpjquota)
2118                 return set_qf_name(sb, GRPQUOTA, &args[0]);
2119         else if (token == Opt_offusrjquota)
2120                 return clear_qf_name(sb, USRQUOTA);
2121         else if (token == Opt_offgrpjquota)
2122                 return clear_qf_name(sb, GRPQUOTA);
2123 #endif
2124         switch (token) {
2125         case Opt_noacl:
2126         case Opt_nouser_xattr:
2127                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
2128                 break;
2129         case Opt_sb:
2130                 return 1;       /* handled by get_sb_block() */
2131         case Opt_removed:
2132                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
2133                 return 1;
2134         case Opt_abort:
2135                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
2136                 return 1;
2137         case Opt_i_version:
2138                 sb->s_flags |= SB_I_VERSION;
2139                 return 1;
2140         case Opt_lazytime:
2141                 sb->s_flags |= SB_LAZYTIME;
2142                 return 1;
2143         case Opt_nolazytime:
2144                 sb->s_flags &= ~SB_LAZYTIME;
2145                 return 1;
2146         case Opt_inlinecrypt:
2147 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2148                 sb->s_flags |= SB_INLINECRYPT;
2149 #else
2150                 ext4_msg(sb, KERN_ERR, "inline encryption not supported");
2151 #endif
2152                 return 1;
2153         }
2154
2155         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2156                 if (token == m->token)
2157                         break;
2158
2159         if (m->token == Opt_err) {
2160                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
2161                          "or missing value", opt);
2162                 return -1;
2163         }
2164
2165         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2166                 ext4_msg(sb, KERN_ERR,
2167                          "Mount option \"%s\" incompatible with ext2", opt);
2168                 return -1;
2169         }
2170         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2171                 ext4_msg(sb, KERN_ERR,
2172                          "Mount option \"%s\" incompatible with ext3", opt);
2173                 return -1;
2174         }
2175
2176         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
2177                 return -1;
2178         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
2179                 return -1;
2180         if (m->flags & MOPT_EXPLICIT) {
2181                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2182                         set_opt2(sb, EXPLICIT_DELALLOC);
2183                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2184                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
2185                 } else
2186                         return -1;
2187         }
2188         if (m->flags & MOPT_CLEAR_ERR)
2189                 clear_opt(sb, ERRORS_MASK);
2190         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
2191                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
2192                          "options when quota turned on");
2193                 return -1;
2194         }
2195
2196         if (m->flags & MOPT_NOSUPPORT) {
2197                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
2198         } else if (token == Opt_commit) {
2199                 if (arg == 0)
2200                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
2201                 else if (arg > INT_MAX / HZ) {
2202                         ext4_msg(sb, KERN_ERR,
2203                                  "Invalid commit interval %d, "
2204                                  "must be smaller than %d",
2205                                  arg, INT_MAX / HZ);
2206                         return -1;
2207                 }
2208                 sbi->s_commit_interval = HZ * arg;
2209         } else if (token == Opt_debug_want_extra_isize) {
2210                 if ((arg & 1) ||
2211                     (arg < 4) ||
2212                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
2213                         ext4_msg(sb, KERN_ERR,
2214                                  "Invalid want_extra_isize %d", arg);
2215                         return -1;
2216                 }
2217                 sbi->s_want_extra_isize = arg;
2218         } else if (token == Opt_max_batch_time) {
2219                 sbi->s_max_batch_time = arg;
2220         } else if (token == Opt_min_batch_time) {
2221                 sbi->s_min_batch_time = arg;
2222         } else if (token == Opt_inode_readahead_blks) {
2223                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
2224                         ext4_msg(sb, KERN_ERR,
2225                                  "EXT4-fs: inode_readahead_blks must be "
2226                                  "0 or a power of 2 smaller than 2^31");
2227                         return -1;
2228                 }
2229                 sbi->s_inode_readahead_blks = arg;
2230         } else if (token == Opt_init_itable) {
2231                 set_opt(sb, INIT_INODE_TABLE);
2232                 if (!args->from)
2233                         arg = EXT4_DEF_LI_WAIT_MULT;
2234                 sbi->s_li_wait_mult = arg;
2235         } else if (token == Opt_max_dir_size_kb) {
2236                 sbi->s_max_dir_size_kb = arg;
2237         } else if (token == Opt_stripe) {
2238                 sbi->s_stripe = arg;
2239         } else if (token == Opt_resuid) {
2240                 uid = make_kuid(current_user_ns(), arg);
2241                 if (!uid_valid(uid)) {
2242                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
2243                         return -1;
2244                 }
2245                 sbi->s_resuid = uid;
2246         } else if (token == Opt_resgid) {
2247                 gid = make_kgid(current_user_ns(), arg);
2248                 if (!gid_valid(gid)) {
2249                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
2250                         return -1;
2251                 }
2252                 sbi->s_resgid = gid;
2253         } else if (token == Opt_journal_dev) {
2254                 if (is_remount) {
2255                         ext4_msg(sb, KERN_ERR,
2256                                  "Cannot specify journal on remount");
2257                         return -1;
2258                 }
2259                 *journal_devnum = arg;
2260         } else if (token == Opt_journal_path) {
2261                 char *journal_path;
2262                 struct inode *journal_inode;
2263                 struct path path;
2264                 int error;
2265
2266                 if (is_remount) {
2267                         ext4_msg(sb, KERN_ERR,
2268                                  "Cannot specify journal on remount");
2269                         return -1;
2270                 }
2271                 journal_path = match_strdup(&args[0]);
2272                 if (!journal_path) {
2273                         ext4_msg(sb, KERN_ERR, "error: could not dup "
2274                                 "journal device string");
2275                         return -1;
2276                 }
2277
2278                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2279                 if (error) {
2280                         ext4_msg(sb, KERN_ERR, "error: could not find "
2281                                 "journal device path: error %d", error);
2282                         kfree(journal_path);
2283                         return -1;
2284                 }
2285
2286                 journal_inode = d_inode(path.dentry);
2287                 if (!S_ISBLK(journal_inode->i_mode)) {
2288                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
2289                                 "is not a block device", journal_path);
2290                         path_put(&path);
2291                         kfree(journal_path);
2292                         return -1;
2293                 }
2294
2295                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
2296                 path_put(&path);
2297                 kfree(journal_path);
2298         } else if (token == Opt_journal_ioprio) {
2299                 if (arg > 7) {
2300                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2301                                  " (must be 0-7)");
2302                         return -1;
2303                 }
2304                 *journal_ioprio =
2305                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2306         } else if (token == Opt_test_dummy_encryption) {
2307                 return ext4_set_test_dummy_encryption(sb, opt, &args[0],
2308                                                       is_remount);
2309         } else if (m->flags & MOPT_DATAJ) {
2310                 if (is_remount) {
2311                         if (!sbi->s_journal)
2312                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2313                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2314                                 ext4_msg(sb, KERN_ERR,
2315                                          "Cannot change data mode on remount");
2316                                 return -1;
2317                         }
2318                 } else {
2319                         clear_opt(sb, DATA_FLAGS);
2320                         sbi->s_mount_opt |= m->mount_opt;
2321                 }
2322 #ifdef CONFIG_QUOTA
2323         } else if (m->flags & MOPT_QFMT) {
2324                 if (sb_any_quota_loaded(sb) &&
2325                     sbi->s_jquota_fmt != m->mount_opt) {
2326                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2327                                  "quota options when quota turned on");
2328                         return -1;
2329                 }
2330                 if (ext4_has_feature_quota(sb)) {
2331                         ext4_msg(sb, KERN_INFO,
2332                                  "Quota format mount options ignored "
2333                                  "when QUOTA feature is enabled");
2334                         return 1;
2335                 }
2336                 sbi->s_jquota_fmt = m->mount_opt;
2337 #endif
2338         } else if (token == Opt_dax || token == Opt_dax_always ||
2339                    token == Opt_dax_inode || token == Opt_dax_never) {
2340 #ifdef CONFIG_FS_DAX
2341                 switch (token) {
2342                 case Opt_dax:
2343                 case Opt_dax_always:
2344                         if (is_remount &&
2345                             (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2346                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2347                         fail_dax_change_remount:
2348                                 ext4_msg(sb, KERN_ERR, "can't change "
2349                                          "dax mount option while remounting");
2350                                 return -1;
2351                         }
2352                         if (is_remount &&
2353                             (test_opt(sb, DATA_FLAGS) ==
2354                              EXT4_MOUNT_JOURNAL_DATA)) {
2355                                     ext4_msg(sb, KERN_ERR, "can't mount with "
2356                                              "both data=journal and dax");
2357                                     return -1;
2358                         }
2359                         ext4_msg(sb, KERN_WARNING,
2360                                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2361                         sbi->s_mount_opt |= EXT4_MOUNT_DAX_ALWAYS;
2362                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2363                         break;
2364                 case Opt_dax_never:
2365                         if (is_remount &&
2366                             (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2367                              (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS)))
2368                                 goto fail_dax_change_remount;
2369                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2370                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2371                         break;
2372                 case Opt_dax_inode:
2373                         if (is_remount &&
2374                             ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2375                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2376                              !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE)))
2377                                 goto fail_dax_change_remount;
2378                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2379                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2380                         /* Strictly for printing options */
2381                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_INODE;
2382                         break;
2383                 }
2384 #else
2385                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2386                 sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2387                 sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2388                 return -1;
2389 #endif
2390         } else if (token == Opt_data_err_abort) {
2391                 sbi->s_mount_opt |= m->mount_opt;
2392         } else if (token == Opt_data_err_ignore) {
2393                 sbi->s_mount_opt &= ~m->mount_opt;
2394         } else {
2395                 if (!args->from)
2396                         arg = 1;
2397                 if (m->flags & MOPT_CLEAR)
2398                         arg = !arg;
2399                 else if (unlikely(!(m->flags & MOPT_SET))) {
2400                         ext4_msg(sb, KERN_WARNING,
2401                                  "buggy handling of option %s", opt);
2402                         WARN_ON(1);
2403                         return -1;
2404                 }
2405                 if (m->flags & MOPT_2) {
2406                         if (arg != 0)
2407                                 sbi->s_mount_opt2 |= m->mount_opt;
2408                         else
2409                                 sbi->s_mount_opt2 &= ~m->mount_opt;
2410                 } else {
2411                         if (arg != 0)
2412                                 sbi->s_mount_opt |= m->mount_opt;
2413                         else
2414                                 sbi->s_mount_opt &= ~m->mount_opt;
2415                 }
2416         }
2417         return 1;
2418 }
2419
2420 static int parse_options(char *options, struct super_block *sb,
2421                          unsigned long *journal_devnum,
2422                          unsigned int *journal_ioprio,
2423                          int is_remount)
2424 {
2425         struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2426         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2427         substring_t args[MAX_OPT_ARGS];
2428         int token;
2429
2430         if (!options)
2431                 return 1;
2432
2433         while ((p = strsep(&options, ",")) != NULL) {
2434                 if (!*p)
2435                         continue;
2436                 /*
2437                  * Initialize args struct so we know whether arg was
2438                  * found; some options take optional arguments.
2439                  */
2440                 args[0].to = args[0].from = NULL;
2441                 token = match_token(p, tokens, args);
2442                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2443                                      journal_ioprio, is_remount) < 0)
2444                         return 0;
2445         }
2446 #ifdef CONFIG_QUOTA
2447         /*
2448          * We do the test below only for project quotas. 'usrquota' and
2449          * 'grpquota' mount options are allowed even without quota feature
2450          * to support legacy quotas in quota files.
2451          */
2452         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2453                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2454                          "Cannot enable project quota enforcement.");
2455                 return 0;
2456         }
2457         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2458         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2459         if (usr_qf_name || grp_qf_name) {
2460                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2461                         clear_opt(sb, USRQUOTA);
2462
2463                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2464                         clear_opt(sb, GRPQUOTA);
2465
2466                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2467                         ext4_msg(sb, KERN_ERR, "old and new quota "
2468                                         "format mixing");
2469                         return 0;
2470                 }
2471
2472                 if (!sbi->s_jquota_fmt) {
2473                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2474                                         "not specified");
2475                         return 0;
2476                 }
2477         }
2478 #endif
2479         if (test_opt(sb, DIOREAD_NOLOCK)) {
2480                 int blocksize =
2481                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2482                 if (blocksize < PAGE_SIZE)
2483                         ext4_msg(sb, KERN_WARNING, "Warning: mounting with an "
2484                                  "experimental mount option 'dioread_nolock' "
2485                                  "for blocksize < PAGE_SIZE");
2486         }
2487         return 1;
2488 }
2489
2490 static inline void ext4_show_quota_options(struct seq_file *seq,
2491                                            struct super_block *sb)
2492 {
2493 #if defined(CONFIG_QUOTA)
2494         struct ext4_sb_info *sbi = EXT4_SB(sb);
2495         char *usr_qf_name, *grp_qf_name;
2496
2497         if (sbi->s_jquota_fmt) {
2498                 char *fmtname = "";
2499
2500                 switch (sbi->s_jquota_fmt) {
2501                 case QFMT_VFS_OLD:
2502                         fmtname = "vfsold";
2503                         break;
2504                 case QFMT_VFS_V0:
2505                         fmtname = "vfsv0";
2506                         break;
2507                 case QFMT_VFS_V1:
2508                         fmtname = "vfsv1";
2509                         break;
2510                 }
2511                 seq_printf(seq, ",jqfmt=%s", fmtname);
2512         }
2513
2514         rcu_read_lock();
2515         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2516         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2517         if (usr_qf_name)
2518                 seq_show_option(seq, "usrjquota", usr_qf_name);
2519         if (grp_qf_name)
2520                 seq_show_option(seq, "grpjquota", grp_qf_name);
2521         rcu_read_unlock();
2522 #endif
2523 }
2524
2525 static const char *token2str(int token)
2526 {
2527         const struct match_token *t;
2528
2529         for (t = tokens; t->token != Opt_err; t++)
2530                 if (t->token == token && !strchr(t->pattern, '='))
2531                         break;
2532         return t->pattern;
2533 }
2534
2535 /*
2536  * Show an option if
2537  *  - it's set to a non-default value OR
2538  *  - if the per-sb default is different from the global default
2539  */
2540 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2541                               int nodefs)
2542 {
2543         struct ext4_sb_info *sbi = EXT4_SB(sb);
2544         struct ext4_super_block *es = sbi->s_es;
2545         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2546         const struct mount_opts *m;
2547         char sep = nodefs ? '\n' : ',';
2548
2549 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2550 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2551
2552         if (sbi->s_sb_block != 1)
2553                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2554
2555         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2556                 int want_set = m->flags & MOPT_SET;
2557                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2558                     (m->flags & MOPT_CLEAR_ERR) || m->flags & MOPT_SKIP)
2559                         continue;
2560                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2561                         continue; /* skip if same as the default */
2562                 if ((want_set &&
2563                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2564                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2565                         continue; /* select Opt_noFoo vs Opt_Foo */
2566                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2567         }
2568
2569         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2570             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2571                 SEQ_OPTS_PRINT("resuid=%u",
2572                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2573         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2574             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2575                 SEQ_OPTS_PRINT("resgid=%u",
2576                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2577         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2578         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2579                 SEQ_OPTS_PUTS("errors=remount-ro");
2580         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2581                 SEQ_OPTS_PUTS("errors=continue");
2582         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2583                 SEQ_OPTS_PUTS("errors=panic");
2584         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2585                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2586         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2587                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2588         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2589                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2590         if (sb->s_flags & SB_I_VERSION)
2591                 SEQ_OPTS_PUTS("i_version");
2592         if (nodefs || sbi->s_stripe)
2593                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2594         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2595                         (sbi->s_mount_opt ^ def_mount_opt)) {
2596                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2597                         SEQ_OPTS_PUTS("data=journal");
2598                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2599                         SEQ_OPTS_PUTS("data=ordered");
2600                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2601                         SEQ_OPTS_PUTS("data=writeback");
2602         }
2603         if (nodefs ||
2604             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2605                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2606                                sbi->s_inode_readahead_blks);
2607
2608         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2609                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2610                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2611         if (nodefs || sbi->s_max_dir_size_kb)
2612                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2613         if (test_opt(sb, DATA_ERR_ABORT))
2614                 SEQ_OPTS_PUTS("data_err=abort");
2615
2616         fscrypt_show_test_dummy_encryption(seq, sep, sb);
2617
2618         if (sb->s_flags & SB_INLINECRYPT)
2619                 SEQ_OPTS_PUTS("inlinecrypt");
2620
2621         if (test_opt(sb, DAX_ALWAYS)) {
2622                 if (IS_EXT2_SB(sb))
2623                         SEQ_OPTS_PUTS("dax");
2624                 else
2625                         SEQ_OPTS_PUTS("dax=always");
2626         } else if (test_opt2(sb, DAX_NEVER)) {
2627                 SEQ_OPTS_PUTS("dax=never");
2628         } else if (test_opt2(sb, DAX_INODE)) {
2629                 SEQ_OPTS_PUTS("dax=inode");
2630         }
2631
2632         if (test_opt2(sb, JOURNAL_FAST_COMMIT))
2633                 SEQ_OPTS_PUTS("fast_commit");
2634
2635         ext4_show_quota_options(seq, sb);
2636         return 0;
2637 }
2638
2639 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2640 {
2641         return _ext4_show_options(seq, root->d_sb, 0);
2642 }
2643
2644 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2645 {
2646         struct super_block *sb = seq->private;
2647         int rc;
2648
2649         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2650         rc = _ext4_show_options(seq, sb, 1);
2651         seq_puts(seq, "\n");
2652         return rc;
2653 }
2654
2655 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2656                             int read_only)
2657 {
2658         struct ext4_sb_info *sbi = EXT4_SB(sb);
2659         int err = 0;
2660
2661         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2662                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2663                          "forcing read-only mode");
2664                 err = -EROFS;
2665                 goto done;
2666         }
2667         if (read_only)
2668                 goto done;
2669         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2670                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2671                          "running e2fsck is recommended");
2672         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2673                 ext4_msg(sb, KERN_WARNING,
2674                          "warning: mounting fs with errors, "
2675                          "running e2fsck is recommended");
2676         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2677                  le16_to_cpu(es->s_mnt_count) >=
2678                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2679                 ext4_msg(sb, KERN_WARNING,
2680                          "warning: maximal mount count reached, "
2681                          "running e2fsck is recommended");
2682         else if (le32_to_cpu(es->s_checkinterval) &&
2683                  (ext4_get_tstamp(es, s_lastcheck) +
2684                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2685                 ext4_msg(sb, KERN_WARNING,
2686                          "warning: checktime reached, "
2687                          "running e2fsck is recommended");
2688         if (!sbi->s_journal)
2689                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2690         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2691                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2692         le16_add_cpu(&es->s_mnt_count, 1);
2693         ext4_update_tstamp(es, s_mtime);
2694         if (sbi->s_journal)
2695                 ext4_set_feature_journal_needs_recovery(sb);
2696
2697         err = ext4_commit_super(sb, 1);
2698 done:
2699         if (test_opt(sb, DEBUG))
2700                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2701                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2702                         sb->s_blocksize,
2703                         sbi->s_groups_count,
2704                         EXT4_BLOCKS_PER_GROUP(sb),
2705                         EXT4_INODES_PER_GROUP(sb),
2706                         sbi->s_mount_opt, sbi->s_mount_opt2);
2707
2708         cleancache_init_fs(sb);
2709         return err;
2710 }
2711
2712 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2713 {
2714         struct ext4_sb_info *sbi = EXT4_SB(sb);
2715         struct flex_groups **old_groups, **new_groups;
2716         int size, i, j;
2717
2718         if (!sbi->s_log_groups_per_flex)
2719                 return 0;
2720
2721         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2722         if (size <= sbi->s_flex_groups_allocated)
2723                 return 0;
2724
2725         new_groups = kvzalloc(roundup_pow_of_two(size *
2726                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2727         if (!new_groups) {
2728                 ext4_msg(sb, KERN_ERR,
2729                          "not enough memory for %d flex group pointers", size);
2730                 return -ENOMEM;
2731         }
2732         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2733                 new_groups[i] = kvzalloc(roundup_pow_of_two(
2734                                          sizeof(struct flex_groups)),
2735                                          GFP_KERNEL);
2736                 if (!new_groups[i]) {
2737                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
2738                                 kvfree(new_groups[j]);
2739                         kvfree(new_groups);
2740                         ext4_msg(sb, KERN_ERR,
2741                                  "not enough memory for %d flex groups", size);
2742                         return -ENOMEM;
2743                 }
2744         }
2745         rcu_read_lock();
2746         old_groups = rcu_dereference(sbi->s_flex_groups);
2747         if (old_groups)
2748                 memcpy(new_groups, old_groups,
2749                        (sbi->s_flex_groups_allocated *
2750                         sizeof(struct flex_groups *)));
2751         rcu_read_unlock();
2752         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2753         sbi->s_flex_groups_allocated = size;
2754         if (old_groups)
2755                 ext4_kvfree_array_rcu(old_groups);
2756         return 0;
2757 }
2758
2759 static int ext4_fill_flex_info(struct super_block *sb)
2760 {
2761         struct ext4_sb_info *sbi = EXT4_SB(sb);
2762         struct ext4_group_desc *gdp = NULL;
2763         struct flex_groups *fg;
2764         ext4_group_t flex_group;
2765         int i, err;
2766
2767         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2768         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2769                 sbi->s_log_groups_per_flex = 0;
2770                 return 1;
2771         }
2772
2773         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2774         if (err)
2775                 goto failed;
2776
2777         for (i = 0; i < sbi->s_groups_count; i++) {
2778                 gdp = ext4_get_group_desc(sb, i, NULL);
2779
2780                 flex_group = ext4_flex_group(sbi, i);
2781                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2782                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2783                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2784                              &fg->free_clusters);
2785                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2786         }
2787
2788         return 1;
2789 failed:
2790         return 0;
2791 }
2792
2793 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2794                                    struct ext4_group_desc *gdp)
2795 {
2796         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2797         __u16 crc = 0;
2798         __le32 le_group = cpu_to_le32(block_group);
2799         struct ext4_sb_info *sbi = EXT4_SB(sb);
2800
2801         if (ext4_has_metadata_csum(sbi->s_sb)) {
2802                 /* Use new metadata_csum algorithm */
2803                 __u32 csum32;
2804                 __u16 dummy_csum = 0;
2805
2806                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2807                                      sizeof(le_group));
2808                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2809                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2810                                      sizeof(dummy_csum));
2811                 offset += sizeof(dummy_csum);
2812                 if (offset < sbi->s_desc_size)
2813                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2814                                              sbi->s_desc_size - offset);
2815
2816                 crc = csum32 & 0xFFFF;
2817                 goto out;
2818         }
2819
2820         /* old crc16 code */
2821         if (!ext4_has_feature_gdt_csum(sb))
2822                 return 0;
2823
2824         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2825         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2826         crc = crc16(crc, (__u8 *)gdp, offset);
2827         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2828         /* for checksum of struct ext4_group_desc do the rest...*/
2829         if (ext4_has_feature_64bit(sb) &&
2830             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2831                 crc = crc16(crc, (__u8 *)gdp + offset,
2832                             le16_to_cpu(sbi->s_es->s_desc_size) -
2833                                 offset);
2834
2835 out:
2836         return cpu_to_le16(crc);
2837 }
2838
2839 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2840                                 struct ext4_group_desc *gdp)
2841 {
2842         if (ext4_has_group_desc_csum(sb) &&
2843             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2844                 return 0;
2845
2846         return 1;
2847 }
2848
2849 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2850                               struct ext4_group_desc *gdp)
2851 {
2852         if (!ext4_has_group_desc_csum(sb))
2853                 return;
2854         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2855 }
2856
2857 /* Called at mount-time, super-block is locked */
2858 static int ext4_check_descriptors(struct super_block *sb,
2859                                   ext4_fsblk_t sb_block,
2860                                   ext4_group_t *first_not_zeroed)
2861 {
2862         struct ext4_sb_info *sbi = EXT4_SB(sb);
2863         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2864         ext4_fsblk_t last_block;
2865         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2866         ext4_fsblk_t block_bitmap;
2867         ext4_fsblk_t inode_bitmap;
2868         ext4_fsblk_t inode_table;
2869         int flexbg_flag = 0;
2870         ext4_group_t i, grp = sbi->s_groups_count;
2871
2872         if (ext4_has_feature_flex_bg(sb))
2873                 flexbg_flag = 1;
2874
2875         ext4_debug("Checking group descriptors");
2876
2877         for (i = 0; i < sbi->s_groups_count; i++) {
2878                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2879
2880                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2881                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2882                 else
2883                         last_block = first_block +
2884                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2885
2886                 if ((grp == sbi->s_groups_count) &&
2887                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2888                         grp = i;
2889
2890                 block_bitmap = ext4_block_bitmap(sb, gdp);
2891                 if (block_bitmap == sb_block) {
2892                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2893                                  "Block bitmap for group %u overlaps "
2894                                  "superblock", i);
2895                         if (!sb_rdonly(sb))
2896                                 return 0;
2897                 }
2898                 if (block_bitmap >= sb_block + 1 &&
2899                     block_bitmap <= last_bg_block) {
2900                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2901                                  "Block bitmap for group %u overlaps "
2902                                  "block group descriptors", i);
2903                         if (!sb_rdonly(sb))
2904                                 return 0;
2905                 }
2906                 if (block_bitmap < first_block || block_bitmap > last_block) {
2907                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2908                                "Block bitmap for group %u not in group "
2909                                "(block %llu)!", i, block_bitmap);
2910                         return 0;
2911                 }
2912                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2913                 if (inode_bitmap == sb_block) {
2914                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2915                                  "Inode bitmap for group %u overlaps "
2916                                  "superblock", i);
2917                         if (!sb_rdonly(sb))
2918                                 return 0;
2919                 }
2920                 if (inode_bitmap >= sb_block + 1 &&
2921                     inode_bitmap <= last_bg_block) {
2922                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2923                                  "Inode bitmap for group %u overlaps "
2924                                  "block group descriptors", i);
2925                         if (!sb_rdonly(sb))
2926                                 return 0;
2927                 }
2928                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2929                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2930                                "Inode bitmap for group %u not in group "
2931                                "(block %llu)!", i, inode_bitmap);
2932                         return 0;
2933                 }
2934                 inode_table = ext4_inode_table(sb, gdp);
2935                 if (inode_table == sb_block) {
2936                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2937                                  "Inode table for group %u overlaps "
2938                                  "superblock", i);
2939                         if (!sb_rdonly(sb))
2940                                 return 0;
2941                 }
2942                 if (inode_table >= sb_block + 1 &&
2943                     inode_table <= last_bg_block) {
2944                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2945                                  "Inode table for group %u overlaps "
2946                                  "block group descriptors", i);
2947                         if (!sb_rdonly(sb))
2948                                 return 0;
2949                 }
2950                 if (inode_table < first_block ||
2951                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2952                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2953                                "Inode table for group %u not in group "
2954                                "(block %llu)!", i, inode_table);
2955                         return 0;
2956                 }
2957                 ext4_lock_group(sb, i);
2958                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2959                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2960                                  "Checksum for group %u failed (%u!=%u)",
2961                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2962                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2963                         if (!sb_rdonly(sb)) {
2964                                 ext4_unlock_group(sb, i);
2965                                 return 0;
2966                         }
2967                 }
2968                 ext4_unlock_group(sb, i);
2969                 if (!flexbg_flag)
2970                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2971         }
2972         if (NULL != first_not_zeroed)
2973                 *first_not_zeroed = grp;
2974         return 1;
2975 }
2976
2977 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2978  * the superblock) which were deleted from all directories, but held open by
2979  * a process at the time of a crash.  We walk the list and try to delete these
2980  * inodes at recovery time (only with a read-write filesystem).
2981  *
2982  * In order to keep the orphan inode chain consistent during traversal (in
2983  * case of crash during recovery), we link each inode into the superblock
2984  * orphan list_head and handle it the same way as an inode deletion during
2985  * normal operation (which journals the operations for us).
2986  *
2987  * We only do an iget() and an iput() on each inode, which is very safe if we
2988  * accidentally point at an in-use or already deleted inode.  The worst that
2989  * can happen in this case is that we get a "bit already cleared" message from
2990  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2991  * e2fsck was run on this filesystem, and it must have already done the orphan
2992  * inode cleanup for us, so we can safely abort without any further action.
2993  */
2994 static void ext4_orphan_cleanup(struct super_block *sb,
2995                                 struct ext4_super_block *es)
2996 {
2997         unsigned int s_flags = sb->s_flags;
2998         int ret, nr_orphans = 0, nr_truncates = 0;
2999 #ifdef CONFIG_QUOTA
3000         int quota_update = 0;
3001         int i;
3002 #endif
3003         if (!es->s_last_orphan) {
3004                 jbd_debug(4, "no orphan inodes to clean up\n");
3005                 return;
3006         }
3007
3008         if (bdev_read_only(sb->s_bdev)) {
3009                 ext4_msg(sb, KERN_ERR, "write access "
3010                         "unavailable, skipping orphan cleanup");
3011                 return;
3012         }
3013
3014         /* Check if feature set would not allow a r/w mount */
3015         if (!ext4_feature_set_ok(sb, 0)) {
3016                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
3017                          "unknown ROCOMPAT features");
3018                 return;
3019         }
3020
3021         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
3022                 /* don't clear list on RO mount w/ errors */
3023                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
3024                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
3025                                   "clearing orphan list.\n");
3026                         es->s_last_orphan = 0;
3027                 }
3028                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
3029                 return;
3030         }
3031
3032         if (s_flags & SB_RDONLY) {
3033                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
3034                 sb->s_flags &= ~SB_RDONLY;
3035         }
3036 #ifdef CONFIG_QUOTA
3037         /* Needed for iput() to work correctly and not trash data */
3038         sb->s_flags |= SB_ACTIVE;
3039
3040         /*
3041          * Turn on quotas which were not enabled for read-only mounts if
3042          * filesystem has quota feature, so that they are updated correctly.
3043          */
3044         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
3045                 int ret = ext4_enable_quotas(sb);
3046
3047                 if (!ret)
3048                         quota_update = 1;
3049                 else
3050                         ext4_msg(sb, KERN_ERR,
3051                                 "Cannot turn on quotas: error %d", ret);
3052         }
3053
3054         /* Turn on journaled quotas used for old sytle */
3055         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3056                 if (EXT4_SB(sb)->s_qf_names[i]) {
3057                         int ret = ext4_quota_on_mount(sb, i);
3058
3059                         if (!ret)
3060                                 quota_update = 1;
3061                         else
3062                                 ext4_msg(sb, KERN_ERR,
3063                                         "Cannot turn on journaled "
3064                                         "quota: type %d: error %d", i, ret);
3065                 }
3066         }
3067 #endif
3068
3069         while (es->s_last_orphan) {
3070                 struct inode *inode;
3071
3072                 /*
3073                  * We may have encountered an error during cleanup; if
3074                  * so, skip the rest.
3075                  */
3076                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
3077                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
3078                         es->s_last_orphan = 0;
3079                         break;
3080                 }
3081
3082                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
3083                 if (IS_ERR(inode)) {
3084                         es->s_last_orphan = 0;
3085                         break;
3086                 }
3087
3088                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
3089                 dquot_initialize(inode);
3090                 if (inode->i_nlink) {
3091                         if (test_opt(sb, DEBUG))
3092                                 ext4_msg(sb, KERN_DEBUG,
3093                                         "%s: truncating inode %lu to %lld bytes",
3094                                         __func__, inode->i_ino, inode->i_size);
3095                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
3096                                   inode->i_ino, inode->i_size);
3097                         inode_lock(inode);
3098                         truncate_inode_pages(inode->i_mapping, inode->i_size);
3099                         ret = ext4_truncate(inode);
3100                         if (ret)
3101                                 ext4_std_error(inode->i_sb, ret);
3102                         inode_unlock(inode);
3103                         nr_truncates++;
3104                 } else {
3105                         if (test_opt(sb, DEBUG))
3106                                 ext4_msg(sb, KERN_DEBUG,
3107                                         "%s: deleting unreferenced inode %lu",
3108                                         __func__, inode->i_ino);
3109                         jbd_debug(2, "deleting unreferenced inode %lu\n",
3110                                   inode->i_ino);
3111                         nr_orphans++;
3112                 }
3113                 iput(inode);  /* The delete magic happens here! */
3114         }
3115
3116 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
3117
3118         if (nr_orphans)
3119                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
3120                        PLURAL(nr_orphans));
3121         if (nr_truncates)
3122                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
3123                        PLURAL(nr_truncates));
3124 #ifdef CONFIG_QUOTA
3125         /* Turn off quotas if they were enabled for orphan cleanup */
3126         if (quota_update) {
3127                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3128                         if (sb_dqopt(sb)->files[i])
3129                                 dquot_quota_off(sb, i);
3130                 }
3131         }
3132 #endif
3133         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
3134 }
3135
3136 /*
3137  * Maximal extent format file size.
3138  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3139  * extent format containers, within a sector_t, and within i_blocks
3140  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3141  * so that won't be a limiting factor.
3142  *
3143  * However there is other limiting factor. We do store extents in the form
3144  * of starting block and length, hence the resulting length of the extent
3145  * covering maximum file size must fit into on-disk format containers as
3146  * well. Given that length is always by 1 unit bigger than max unit (because
3147  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3148  *
3149  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3150  */
3151 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3152 {
3153         loff_t res;
3154         loff_t upper_limit = MAX_LFS_FILESIZE;
3155
3156         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3157
3158         if (!has_huge_files) {
3159                 upper_limit = (1LL << 32) - 1;
3160
3161                 /* total blocks in file system block size */
3162                 upper_limit >>= (blkbits - 9);
3163                 upper_limit <<= blkbits;
3164         }
3165
3166         /*
3167          * 32-bit extent-start container, ee_block. We lower the maxbytes
3168          * by one fs block, so ee_len can cover the extent of maximum file
3169          * size
3170          */
3171         res = (1LL << 32) - 1;
3172         res <<= blkbits;
3173
3174         /* Sanity check against vm- & vfs- imposed limits */
3175         if (res > upper_limit)
3176                 res = upper_limit;
3177
3178         return res;
3179 }
3180
3181 /*
3182  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3183  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3184  * We need to be 1 filesystem block less than the 2^48 sector limit.
3185  */
3186 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3187 {
3188         loff_t res = EXT4_NDIR_BLOCKS;
3189         int meta_blocks;
3190         loff_t upper_limit;
3191         /* This is calculated to be the largest file size for a dense, block
3192          * mapped file such that the file's total number of 512-byte sectors,
3193          * including data and all indirect blocks, does not exceed (2^48 - 1).
3194          *
3195          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3196          * number of 512-byte sectors of the file.
3197          */
3198
3199         if (!has_huge_files) {
3200                 /*
3201                  * !has_huge_files or implies that the inode i_block field
3202                  * represents total file blocks in 2^32 512-byte sectors ==
3203                  * size of vfs inode i_blocks * 8
3204                  */
3205                 upper_limit = (1LL << 32) - 1;
3206
3207                 /* total blocks in file system block size */
3208                 upper_limit >>= (bits - 9);
3209
3210         } else {
3211                 /*
3212                  * We use 48 bit ext4_inode i_blocks
3213                  * With EXT4_HUGE_FILE_FL set the i_blocks
3214                  * represent total number of blocks in
3215                  * file system block size
3216                  */
3217                 upper_limit = (1LL << 48) - 1;
3218
3219         }
3220
3221         /* indirect blocks */
3222         meta_blocks = 1;
3223         /* double indirect blocks */
3224         meta_blocks += 1 + (1LL << (bits-2));
3225         /* tripple indirect blocks */
3226         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
3227
3228         upper_limit -= meta_blocks;
3229         upper_limit <<= bits;
3230
3231         res += 1LL << (bits-2);
3232         res += 1LL << (2*(bits-2));
3233         res += 1LL << (3*(bits-2));
3234         res <<= bits;
3235         if (res > upper_limit)
3236                 res = upper_limit;
3237
3238         if (res > MAX_LFS_FILESIZE)
3239                 res = MAX_LFS_FILESIZE;
3240
3241         return res;
3242 }
3243
3244 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3245                                    ext4_fsblk_t logical_sb_block, int nr)
3246 {
3247         struct ext4_sb_info *sbi = EXT4_SB(sb);
3248         ext4_group_t bg, first_meta_bg;
3249         int has_super = 0;
3250
3251         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3252
3253         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3254                 return logical_sb_block + nr + 1;
3255         bg = sbi->s_desc_per_block * nr;
3256         if (ext4_bg_has_super(sb, bg))
3257                 has_super = 1;
3258
3259         /*
3260          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3261          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3262          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3263          * compensate.
3264          */
3265         if (sb->s_blocksize == 1024 && nr == 0 &&
3266             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3267                 has_super++;
3268
3269         return (has_super + ext4_group_first_block_no(sb, bg));
3270 }
3271
3272 /**
3273  * ext4_get_stripe_size: Get the stripe size.
3274  * @sbi: In memory super block info
3275  *
3276  * If we have specified it via mount option, then
3277  * use the mount option value. If the value specified at mount time is
3278  * greater than the blocks per group use the super block value.
3279  * If the super block value is greater than blocks per group return 0.
3280  * Allocator needs it be less than blocks per group.
3281  *
3282  */
3283 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3284 {
3285         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3286         unsigned long stripe_width =
3287                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3288         int ret;
3289
3290         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3291                 ret = sbi->s_stripe;
3292         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3293                 ret = stripe_width;
3294         else if (stride && stride <= sbi->s_blocks_per_group)
3295                 ret = stride;
3296         else
3297                 ret = 0;
3298
3299         /*
3300          * If the stripe width is 1, this makes no sense and
3301          * we set it to 0 to turn off stripe handling code.
3302          */
3303         if (ret <= 1)
3304                 ret = 0;
3305
3306         return ret;
3307 }
3308
3309 /*
3310  * Check whether this filesystem can be mounted based on
3311  * the features present and the RDONLY/RDWR mount requested.
3312  * Returns 1 if this filesystem can be mounted as requested,
3313  * 0 if it cannot be.
3314  */
3315 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
3316 {
3317         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3318                 ext4_msg(sb, KERN_ERR,
3319                         "Couldn't mount because of "
3320                         "unsupported optional features (%x)",
3321                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3322                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3323                 return 0;
3324         }
3325
3326 #ifndef CONFIG_UNICODE
3327         if (ext4_has_feature_casefold(sb)) {
3328                 ext4_msg(sb, KERN_ERR,
3329                          "Filesystem with casefold feature cannot be "
3330                          "mounted without CONFIG_UNICODE");
3331                 return 0;
3332         }
3333 #endif
3334
3335         if (readonly)
3336                 return 1;
3337
3338         if (ext4_has_feature_readonly(sb)) {
3339                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3340                 sb->s_flags |= SB_RDONLY;
3341                 return 1;
3342         }
3343
3344         /* Check that feature set is OK for a read-write mount */
3345         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3346                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3347                          "unsupported optional features (%x)",
3348                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3349                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3350                 return 0;
3351         }
3352         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3353                 ext4_msg(sb, KERN_ERR,
3354                          "Can't support bigalloc feature without "
3355                          "extents feature\n");
3356                 return 0;
3357         }
3358
3359 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3360         if (!readonly && (ext4_has_feature_quota(sb) ||
3361                           ext4_has_feature_project(sb))) {
3362                 ext4_msg(sb, KERN_ERR,
3363                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3364                 return 0;
3365         }
3366 #endif  /* CONFIG_QUOTA */
3367         return 1;
3368 }
3369
3370 /*
3371  * This function is called once a day if we have errors logged
3372  * on the file system
3373  */
3374 static void print_daily_error_info(struct timer_list *t)
3375 {
3376         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3377         struct super_block *sb = sbi->s_sb;
3378         struct ext4_super_block *es = sbi->s_es;
3379
3380         if (es->s_error_count)
3381                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3382                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3383                          le32_to_cpu(es->s_error_count));
3384         if (es->s_first_error_time) {
3385                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3386                        sb->s_id,
3387                        ext4_get_tstamp(es, s_first_error_time),
3388                        (int) sizeof(es->s_first_error_func),
3389                        es->s_first_error_func,
3390                        le32_to_cpu(es->s_first_error_line));
3391                 if (es->s_first_error_ino)
3392                         printk(KERN_CONT ": inode %u",
3393                                le32_to_cpu(es->s_first_error_ino));
3394                 if (es->s_first_error_block)
3395                         printk(KERN_CONT ": block %llu", (unsigned long long)
3396                                le64_to_cpu(es->s_first_error_block));
3397                 printk(KERN_CONT "\n");
3398         }
3399         if (es->s_last_error_time) {
3400                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3401                        sb->s_id,
3402                        ext4_get_tstamp(es, s_last_error_time),
3403                        (int) sizeof(es->s_last_error_func),
3404                        es->s_last_error_func,
3405                        le32_to_cpu(es->s_last_error_line));
3406                 if (es->s_last_error_ino)
3407                         printk(KERN_CONT ": inode %u",
3408                                le32_to_cpu(es->s_last_error_ino));
3409                 if (es->s_last_error_block)
3410                         printk(KERN_CONT ": block %llu", (unsigned long long)
3411                                le64_to_cpu(es->s_last_error_block));
3412                 printk(KERN_CONT "\n");
3413         }
3414         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3415 }
3416
3417 /* Find next suitable group and run ext4_init_inode_table */
3418 static int ext4_run_li_request(struct ext4_li_request *elr)
3419 {
3420         struct ext4_group_desc *gdp = NULL;
3421         struct super_block *sb = elr->lr_super;
3422         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3423         ext4_group_t group = elr->lr_next_group;
3424         unsigned long timeout = 0;
3425         unsigned int prefetch_ios = 0;
3426         int ret = 0;
3427
3428         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3429                 elr->lr_next_group = ext4_mb_prefetch(sb, group,
3430                                 EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3431                 if (prefetch_ios)
3432                         ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3433                                               prefetch_ios);
3434                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3435                                             prefetch_ios);
3436                 if (group >= elr->lr_next_group) {
3437                         ret = 1;
3438                         if (elr->lr_first_not_zeroed != ngroups &&
3439                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3440                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3441                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3442                                 ret = 0;
3443                         }
3444                 }
3445                 return ret;
3446         }
3447
3448         for (; group < ngroups; group++) {
3449                 gdp = ext4_get_group_desc(sb, group, NULL);
3450                 if (!gdp) {
3451                         ret = 1;
3452                         break;
3453                 }
3454
3455                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3456                         break;
3457         }
3458
3459         if (group >= ngroups)
3460                 ret = 1;
3461
3462         if (!ret) {
3463                 timeout = jiffies;
3464                 ret = ext4_init_inode_table(sb, group,
3465                                             elr->lr_timeout ? 0 : 1);
3466                 trace_ext4_lazy_itable_init(sb, group);
3467                 if (elr->lr_timeout == 0) {
3468                         timeout = (jiffies - timeout) *
3469                                 EXT4_SB(elr->lr_super)->s_li_wait_mult;
3470                         elr->lr_timeout = timeout;
3471                 }
3472                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3473                 elr->lr_next_group = group + 1;
3474         }
3475         return ret;
3476 }
3477
3478 /*
3479  * Remove lr_request from the list_request and free the
3480  * request structure. Should be called with li_list_mtx held
3481  */
3482 static void ext4_remove_li_request(struct ext4_li_request *elr)
3483 {
3484         if (!elr)
3485                 return;
3486
3487         list_del(&elr->lr_request);
3488         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3489         kfree(elr);
3490 }
3491
3492 static void ext4_unregister_li_request(struct super_block *sb)
3493 {
3494         mutex_lock(&ext4_li_mtx);
3495         if (!ext4_li_info) {
3496                 mutex_unlock(&ext4_li_mtx);
3497                 return;
3498         }
3499
3500         mutex_lock(&ext4_li_info->li_list_mtx);
3501         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3502         mutex_unlock(&ext4_li_info->li_list_mtx);
3503         mutex_unlock(&ext4_li_mtx);
3504 }
3505
3506 static struct task_struct *ext4_lazyinit_task;
3507
3508 /*
3509  * This is the function where ext4lazyinit thread lives. It walks
3510  * through the request list searching for next scheduled filesystem.
3511  * When such a fs is found, run the lazy initialization request
3512  * (ext4_rn_li_request) and keep track of the time spend in this
3513  * function. Based on that time we compute next schedule time of
3514  * the request. When walking through the list is complete, compute
3515  * next waking time and put itself into sleep.
3516  */
3517 static int ext4_lazyinit_thread(void *arg)
3518 {
3519         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3520         struct list_head *pos, *n;
3521         struct ext4_li_request *elr;
3522         unsigned long next_wakeup, cur;
3523
3524         BUG_ON(NULL == eli);
3525
3526 cont_thread:
3527         while (true) {
3528                 next_wakeup = MAX_JIFFY_OFFSET;
3529
3530                 mutex_lock(&eli->li_list_mtx);
3531                 if (list_empty(&eli->li_request_list)) {
3532                         mutex_unlock(&eli->li_list_mtx);
3533                         goto exit_thread;
3534                 }
3535                 list_for_each_safe(pos, n, &eli->li_request_list) {
3536                         int err = 0;
3537                         int progress = 0;
3538                         elr = list_entry(pos, struct ext4_li_request,
3539                                          lr_request);
3540
3541                         if (time_before(jiffies, elr->lr_next_sched)) {
3542                                 if (time_before(elr->lr_next_sched, next_wakeup))
3543                                         next_wakeup = elr->lr_next_sched;
3544                                 continue;
3545                         }
3546                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3547                                 if (sb_start_write_trylock(elr->lr_super)) {
3548                                         progress = 1;
3549                                         /*
3550                                          * We hold sb->s_umount, sb can not
3551                                          * be removed from the list, it is
3552                                          * now safe to drop li_list_mtx
3553                                          */
3554                                         mutex_unlock(&eli->li_list_mtx);
3555                                         err = ext4_run_li_request(elr);
3556                                         sb_end_write(elr->lr_super);
3557                                         mutex_lock(&eli->li_list_mtx);
3558                                         n = pos->next;
3559                                 }
3560                                 up_read((&elr->lr_super->s_umount));
3561                         }
3562                         /* error, remove the lazy_init job */
3563                         if (err) {
3564                                 ext4_remove_li_request(elr);
3565                                 continue;
3566                         }
3567                         if (!progress) {
3568                                 elr->lr_next_sched = jiffies +
3569                                         (prandom_u32()
3570                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3571                         }
3572                         if (time_before(elr->lr_next_sched, next_wakeup))
3573                                 next_wakeup = elr->lr_next_sched;
3574                 }
3575                 mutex_unlock(&eli->li_list_mtx);
3576
3577                 try_to_freeze();
3578
3579                 cur = jiffies;
3580                 if ((time_after_eq(cur, next_wakeup)) ||
3581                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3582                         cond_resched();
3583                         continue;
3584                 }
3585
3586                 schedule_timeout_interruptible(next_wakeup - cur);
3587
3588                 if (kthread_should_stop()) {
3589                         ext4_clear_request_list();
3590                         goto exit_thread;
3591                 }
3592         }
3593
3594 exit_thread:
3595         /*
3596          * It looks like the request list is empty, but we need
3597          * to check it under the li_list_mtx lock, to prevent any
3598          * additions into it, and of course we should lock ext4_li_mtx
3599          * to atomically free the list and ext4_li_info, because at
3600          * this point another ext4 filesystem could be registering
3601          * new one.
3602          */
3603         mutex_lock(&ext4_li_mtx);
3604         mutex_lock(&eli->li_list_mtx);
3605         if (!list_empty(&eli->li_request_list)) {
3606                 mutex_unlock(&eli->li_list_mtx);
3607                 mutex_unlock(&ext4_li_mtx);
3608                 goto cont_thread;
3609         }
3610         mutex_unlock(&eli->li_list_mtx);
3611         kfree(ext4_li_info);
3612         ext4_li_info = NULL;
3613         mutex_unlock(&ext4_li_mtx);
3614
3615         return 0;
3616 }
3617
3618 static void ext4_clear_request_list(void)
3619 {
3620         struct list_head *pos, *n;
3621         struct ext4_li_request *elr;
3622
3623         mutex_lock(&ext4_li_info->li_list_mtx);
3624         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3625                 elr = list_entry(pos, struct ext4_li_request,
3626                                  lr_request);
3627                 ext4_remove_li_request(elr);
3628         }
3629         mutex_unlock(&ext4_li_info->li_list_mtx);
3630 }
3631
3632 static int ext4_run_lazyinit_thread(void)
3633 {
3634         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3635                                          ext4_li_info, "ext4lazyinit");
3636         if (IS_ERR(ext4_lazyinit_task)) {
3637                 int err = PTR_ERR(ext4_lazyinit_task);
3638                 ext4_clear_request_list();
3639                 kfree(ext4_li_info);
3640                 ext4_li_info = NULL;
3641                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3642                                  "initialization thread\n",
3643                                  err);
3644                 return err;
3645         }
3646         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3647         return 0;
3648 }
3649
3650 /*
3651  * Check whether it make sense to run itable init. thread or not.
3652  * If there is at least one uninitialized inode table, return
3653  * corresponding group number, else the loop goes through all
3654  * groups and return total number of groups.
3655  */
3656 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3657 {
3658         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3659         struct ext4_group_desc *gdp = NULL;
3660
3661         if (!ext4_has_group_desc_csum(sb))
3662                 return ngroups;
3663
3664         for (group = 0; group < ngroups; group++) {
3665                 gdp = ext4_get_group_desc(sb, group, NULL);
3666                 if (!gdp)
3667                         continue;
3668
3669                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3670                         break;
3671         }
3672
3673         return group;
3674 }
3675
3676 static int ext4_li_info_new(void)
3677 {
3678         struct ext4_lazy_init *eli = NULL;
3679
3680         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3681         if (!eli)
3682                 return -ENOMEM;
3683
3684         INIT_LIST_HEAD(&eli->li_request_list);
3685         mutex_init(&eli->li_list_mtx);
3686
3687         eli->li_state |= EXT4_LAZYINIT_QUIT;
3688
3689         ext4_li_info = eli;
3690
3691         return 0;
3692 }
3693
3694 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3695                                             ext4_group_t start)
3696 {
3697         struct ext4_li_request *elr;
3698
3699         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3700         if (!elr)
3701                 return NULL;
3702
3703         elr->lr_super = sb;
3704         elr->lr_first_not_zeroed = start;
3705         if (test_opt(sb, PREFETCH_BLOCK_BITMAPS))
3706                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3707         else {
3708                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3709                 elr->lr_next_group = start;
3710         }
3711
3712         /*
3713          * Randomize first schedule time of the request to
3714          * spread the inode table initialization requests
3715          * better.
3716          */
3717         elr->lr_next_sched = jiffies + (prandom_u32() %
3718                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3719         return elr;
3720 }
3721
3722 int ext4_register_li_request(struct super_block *sb,
3723                              ext4_group_t first_not_zeroed)
3724 {
3725         struct ext4_sb_info *sbi = EXT4_SB(sb);
3726         struct ext4_li_request *elr = NULL;
3727         ext4_group_t ngroups = sbi->s_groups_count;
3728         int ret = 0;
3729
3730         mutex_lock(&ext4_li_mtx);
3731         if (sbi->s_li_request != NULL) {
3732                 /*
3733                  * Reset timeout so it can be computed again, because
3734                  * s_li_wait_mult might have changed.
3735                  */
3736                 sbi->s_li_request->lr_timeout = 0;
3737                 goto out;
3738         }
3739
3740         if (!test_opt(sb, PREFETCH_BLOCK_BITMAPS) &&
3741             (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3742              !test_opt(sb, INIT_INODE_TABLE)))
3743                 goto out;
3744
3745         elr = ext4_li_request_new(sb, first_not_zeroed);
3746         if (!elr) {
3747                 ret = -ENOMEM;
3748                 goto out;
3749         }
3750
3751         if (NULL == ext4_li_info) {
3752                 ret = ext4_li_info_new();
3753                 if (ret)
3754                         goto out;
3755         }
3756
3757         mutex_lock(&ext4_li_info->li_list_mtx);
3758         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3759         mutex_unlock(&ext4_li_info->li_list_mtx);
3760
3761         sbi->s_li_request = elr;
3762         /*
3763          * set elr to NULL here since it has been inserted to
3764          * the request_list and the removal and free of it is
3765          * handled by ext4_clear_request_list from now on.
3766          */
3767         elr = NULL;
3768
3769         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3770                 ret = ext4_run_lazyinit_thread();
3771                 if (ret)
3772                         goto out;
3773         }
3774 out:
3775         mutex_unlock(&ext4_li_mtx);
3776         if (ret)
3777                 kfree(elr);
3778         return ret;
3779 }
3780
3781 /*
3782  * We do not need to lock anything since this is called on
3783  * module unload.
3784  */
3785 static void ext4_destroy_lazyinit_thread(void)
3786 {
3787         /*
3788          * If thread exited earlier
3789          * there's nothing to be done.
3790          */
3791         if (!ext4_li_info || !ext4_lazyinit_task)
3792                 return;
3793
3794         kthread_stop(ext4_lazyinit_task);
3795 }
3796
3797 static int set_journal_csum_feature_set(struct super_block *sb)
3798 {
3799         int ret = 1;
3800         int compat, incompat;
3801         struct ext4_sb_info *sbi = EXT4_SB(sb);
3802
3803         if (ext4_has_metadata_csum(sb)) {
3804                 /* journal checksum v3 */
3805                 compat = 0;
3806                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3807         } else {
3808                 /* journal checksum v1 */
3809                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3810                 incompat = 0;
3811         }
3812
3813         jbd2_journal_clear_features(sbi->s_journal,
3814                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3815                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3816                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3817         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3818                 ret = jbd2_journal_set_features(sbi->s_journal,
3819                                 compat, 0,
3820                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3821                                 incompat);
3822         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3823                 ret = jbd2_journal_set_features(sbi->s_journal,
3824                                 compat, 0,
3825                                 incompat);
3826                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3827                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3828         } else {
3829                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3830                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3831         }
3832
3833         return ret;
3834 }
3835
3836 /*
3837  * Note: calculating the overhead so we can be compatible with
3838  * historical BSD practice is quite difficult in the face of
3839  * clusters/bigalloc.  This is because multiple metadata blocks from
3840  * different block group can end up in the same allocation cluster.
3841  * Calculating the exact overhead in the face of clustered allocation
3842  * requires either O(all block bitmaps) in memory or O(number of block
3843  * groups**2) in time.  We will still calculate the superblock for
3844  * older file systems --- and if we come across with a bigalloc file
3845  * system with zero in s_overhead_clusters the estimate will be close to
3846  * correct especially for very large cluster sizes --- but for newer
3847  * file systems, it's better to calculate this figure once at mkfs
3848  * time, and store it in the superblock.  If the superblock value is
3849  * present (even for non-bigalloc file systems), we will use it.
3850  */
3851 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3852                           char *buf)
3853 {
3854         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3855         struct ext4_group_desc  *gdp;
3856         ext4_fsblk_t            first_block, last_block, b;
3857         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3858         int                     s, j, count = 0;
3859
3860         if (!ext4_has_feature_bigalloc(sb))
3861                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3862                         sbi->s_itb_per_group + 2);
3863
3864         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3865                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3866         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3867         for (i = 0; i < ngroups; i++) {
3868                 gdp = ext4_get_group_desc(sb, i, NULL);
3869                 b = ext4_block_bitmap(sb, gdp);
3870                 if (b >= first_block && b <= last_block) {
3871                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3872                         count++;
3873                 }
3874                 b = ext4_inode_bitmap(sb, gdp);
3875                 if (b >= first_block && b <= last_block) {
3876                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3877                         count++;
3878                 }
3879                 b = ext4_inode_table(sb, gdp);
3880                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3881                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3882                                 int c = EXT4_B2C(sbi, b - first_block);
3883                                 ext4_set_bit(c, buf);
3884                                 count++;
3885                         }
3886                 if (i != grp)
3887                         continue;
3888                 s = 0;
3889                 if (ext4_bg_has_super(sb, grp)) {
3890                         ext4_set_bit(s++, buf);
3891                         count++;
3892                 }
3893                 j = ext4_bg_num_gdb(sb, grp);
3894                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3895                         ext4_error(sb, "Invalid number of block group "
3896                                    "descriptor blocks: %d", j);
3897                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3898                 }
3899                 count += j;
3900                 for (; j > 0; j--)
3901                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3902         }
3903         if (!count)
3904                 return 0;
3905         return EXT4_CLUSTERS_PER_GROUP(sb) -
3906                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3907 }
3908
3909 /*
3910  * Compute the overhead and stash it in sbi->s_overhead
3911  */
3912 int ext4_calculate_overhead(struct super_block *sb)
3913 {
3914         struct ext4_sb_info *sbi = EXT4_SB(sb);
3915         struct ext4_super_block *es = sbi->s_es;
3916         struct inode *j_inode;
3917         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3918         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3919         ext4_fsblk_t overhead = 0;
3920         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3921
3922         if (!buf)
3923                 return -ENOMEM;
3924
3925         /*
3926          * Compute the overhead (FS structures).  This is constant
3927          * for a given filesystem unless the number of block groups
3928          * changes so we cache the previous value until it does.
3929          */
3930
3931         /*
3932          * All of the blocks before first_data_block are overhead
3933          */
3934         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3935
3936         /*
3937          * Add the overhead found in each block group
3938          */
3939         for (i = 0; i < ngroups; i++) {
3940                 int blks;
3941
3942                 blks = count_overhead(sb, i, buf);
3943                 overhead += blks;
3944                 if (blks)
3945                         memset(buf, 0, PAGE_SIZE);
3946                 cond_resched();
3947         }
3948
3949         /*
3950          * Add the internal journal blocks whether the journal has been
3951          * loaded or not
3952          */
3953         if (sbi->s_journal && !sbi->s_journal_bdev)
3954                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3955         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3956                 /* j_inum for internal journal is non-zero */
3957                 j_inode = ext4_get_journal_inode(sb, j_inum);
3958                 if (j_inode) {
3959                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3960                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3961                         iput(j_inode);
3962                 } else {
3963                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3964                 }
3965         }
3966         sbi->s_overhead = overhead;
3967         smp_wmb();
3968         free_page((unsigned long) buf);
3969         return 0;
3970 }
3971
3972 static void ext4_set_resv_clusters(struct super_block *sb)
3973 {
3974         ext4_fsblk_t resv_clusters;
3975         struct ext4_sb_info *sbi = EXT4_SB(sb);
3976
3977         /*
3978          * There's no need to reserve anything when we aren't using extents.
3979          * The space estimates are exact, there are no unwritten extents,
3980          * hole punching doesn't need new metadata... This is needed especially
3981          * to keep ext2/3 backward compatibility.
3982          */
3983         if (!ext4_has_feature_extents(sb))
3984                 return;
3985         /*
3986          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3987          * This should cover the situations where we can not afford to run
3988          * out of space like for example punch hole, or converting
3989          * unwritten extents in delalloc path. In most cases such
3990          * allocation would require 1, or 2 blocks, higher numbers are
3991          * very rare.
3992          */
3993         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3994                          sbi->s_cluster_bits);
3995
3996         do_div(resv_clusters, 50);
3997         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3998
3999         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4000 }
4001
4002 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
4003 {
4004         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
4005         char *orig_data = kstrdup(data, GFP_KERNEL);
4006         struct buffer_head *bh, **group_desc;
4007         struct ext4_super_block *es = NULL;
4008         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4009         struct flex_groups **flex_groups;
4010         ext4_fsblk_t block;
4011         ext4_fsblk_t sb_block = get_sb_block(&data);
4012         ext4_fsblk_t logical_sb_block;
4013         unsigned long offset = 0;
4014         unsigned long journal_devnum = 0;
4015         unsigned long def_mount_opts;
4016         struct inode *root;
4017         const char *descr;
4018         int ret = -ENOMEM;
4019         int blocksize, clustersize;
4020         unsigned int db_count;
4021         unsigned int i;
4022         int needs_recovery, has_huge_files;
4023         __u64 blocks_count;
4024         int err = 0;
4025         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4026         ext4_group_t first_not_zeroed;
4027
4028         if ((data && !orig_data) || !sbi)
4029                 goto out_free_base;
4030
4031         sbi->s_daxdev = dax_dev;
4032         sbi->s_blockgroup_lock =
4033                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4034         if (!sbi->s_blockgroup_lock)
4035                 goto out_free_base;
4036
4037         sb->s_fs_info = sbi;
4038         sbi->s_sb = sb;
4039         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
4040         sbi->s_sb_block = sb_block;
4041         if (sb->s_bdev->bd_part)
4042                 sbi->s_sectors_written_start =
4043                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
4044
4045         /* Cleanup superblock name */
4046         strreplace(sb->s_id, '/', '!');
4047
4048         /* -EINVAL is default */
4049         ret = -EINVAL;
4050         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
4051         if (!blocksize) {
4052                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
4053                 goto out_fail;
4054         }
4055
4056         /*
4057          * The ext4 superblock will not be buffer aligned for other than 1kB
4058          * block sizes.  We need to calculate the offset from buffer start.
4059          */
4060         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
4061                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4062                 offset = do_div(logical_sb_block, blocksize);
4063         } else {
4064                 logical_sb_block = sb_block;
4065         }
4066
4067         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4068         if (IS_ERR(bh)) {
4069                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
4070                 ret = PTR_ERR(bh);
4071                 bh = NULL;
4072                 goto out_fail;
4073         }
4074         /*
4075          * Note: s_es must be initialized as soon as possible because
4076          *       some ext4 macro-instructions depend on its value
4077          */
4078         es = (struct ext4_super_block *) (bh->b_data + offset);
4079         sbi->s_es = es;
4080         sb->s_magic = le16_to_cpu(es->s_magic);
4081         if (sb->s_magic != EXT4_SUPER_MAGIC)
4082                 goto cantfind_ext4;
4083         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
4084
4085         /* Warn if metadata_csum and gdt_csum are both set. */
4086         if (ext4_has_feature_metadata_csum(sb) &&
4087             ext4_has_feature_gdt_csum(sb))
4088                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4089                              "redundant flags; please run fsck.");
4090
4091         /* Check for a known checksum algorithm */
4092         if (!ext4_verify_csum_type(sb, es)) {
4093                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4094                          "unknown checksum algorithm.");
4095                 silent = 1;
4096                 goto cantfind_ext4;
4097         }
4098
4099         /* Load the checksum driver */
4100         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4101         if (IS_ERR(sbi->s_chksum_driver)) {
4102                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4103                 ret = PTR_ERR(sbi->s_chksum_driver);
4104                 sbi->s_chksum_driver = NULL;
4105                 goto failed_mount;
4106         }
4107
4108         /* Check superblock checksum */
4109         if (!ext4_superblock_csum_verify(sb, es)) {
4110                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4111                          "invalid superblock checksum.  Run e2fsck?");
4112                 silent = 1;
4113                 ret = -EFSBADCRC;
4114                 goto cantfind_ext4;
4115         }
4116
4117         /* Precompute checksum seed for all metadata */
4118         if (ext4_has_feature_csum_seed(sb))
4119                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4120         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4121                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4122                                                sizeof(es->s_uuid));
4123
4124         /* Set defaults before we parse the mount options */
4125         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4126         set_opt(sb, INIT_INODE_TABLE);
4127         if (def_mount_opts & EXT4_DEFM_DEBUG)
4128                 set_opt(sb, DEBUG);
4129         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4130                 set_opt(sb, GRPID);
4131         if (def_mount_opts & EXT4_DEFM_UID16)
4132                 set_opt(sb, NO_UID32);
4133         /* xattr user namespace & acls are now defaulted on */
4134         set_opt(sb, XATTR_USER);
4135 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4136         set_opt(sb, POSIX_ACL);
4137 #endif
4138         if (ext4_has_feature_fast_commit(sb))
4139                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4140         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4141         if (ext4_has_metadata_csum(sb))
4142                 set_opt(sb, JOURNAL_CHECKSUM);
4143
4144         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4145                 set_opt(sb, JOURNAL_DATA);
4146         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4147                 set_opt(sb, ORDERED_DATA);
4148         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4149                 set_opt(sb, WRITEBACK_DATA);
4150
4151         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
4152                 set_opt(sb, ERRORS_PANIC);
4153         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
4154                 set_opt(sb, ERRORS_CONT);
4155         else
4156                 set_opt(sb, ERRORS_RO);
4157         /* block_validity enabled by default; disable with noblock_validity */
4158         set_opt(sb, BLOCK_VALIDITY);
4159         if (def_mount_opts & EXT4_DEFM_DISCARD)
4160                 set_opt(sb, DISCARD);
4161
4162         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
4163         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
4164         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
4165         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
4166         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
4167
4168         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4169                 set_opt(sb, BARRIER);
4170
4171         /*
4172          * enable delayed allocation by default
4173          * Use -o nodelalloc to turn it off
4174          */
4175         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4176             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4177                 set_opt(sb, DELALLOC);
4178
4179         /*
4180          * set default s_li_wait_mult for lazyinit, for the case there is
4181          * no mount option specified.
4182          */
4183         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
4184
4185         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
4186
4187         if (blocksize == PAGE_SIZE)
4188                 set_opt(sb, DIOREAD_NOLOCK);
4189
4190         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
4191             blocksize > EXT4_MAX_BLOCK_SIZE) {
4192                 ext4_msg(sb, KERN_ERR,
4193                        "Unsupported filesystem blocksize %d (%d log_block_size)",
4194                          blocksize, le32_to_cpu(es->s_log_block_size));
4195                 goto failed_mount;
4196         }
4197
4198         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4199                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4200                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4201         } else {
4202                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4203                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4204                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4205                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4206                                  sbi->s_first_ino);
4207                         goto failed_mount;
4208                 }
4209                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4210                     (!is_power_of_2(sbi->s_inode_size)) ||
4211                     (sbi->s_inode_size > blocksize)) {
4212                         ext4_msg(sb, KERN_ERR,
4213                                "unsupported inode size: %d",
4214                                sbi->s_inode_size);
4215                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
4216                         goto failed_mount;
4217                 }
4218                 /*
4219                  * i_atime_extra is the last extra field available for
4220                  * [acm]times in struct ext4_inode. Checking for that
4221                  * field should suffice to ensure we have extra space
4222                  * for all three.
4223                  */
4224                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4225                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4226                         sb->s_time_gran = 1;
4227                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4228                 } else {
4229                         sb->s_time_gran = NSEC_PER_SEC;
4230                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4231                 }
4232                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4233         }
4234         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4235                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4236                         EXT4_GOOD_OLD_INODE_SIZE;
4237                 if (ext4_has_feature_extra_isize(sb)) {
4238                         unsigned v, max = (sbi->s_inode_size -
4239                                            EXT4_GOOD_OLD_INODE_SIZE);
4240
4241                         v = le16_to_cpu(es->s_want_extra_isize);
4242                         if (v > max) {
4243                                 ext4_msg(sb, KERN_ERR,
4244                                          "bad s_want_extra_isize: %d", v);
4245                                 goto failed_mount;
4246                         }
4247                         if (sbi->s_want_extra_isize < v)
4248                                 sbi->s_want_extra_isize = v;
4249
4250                         v = le16_to_cpu(es->s_min_extra_isize);
4251                         if (v > max) {
4252                                 ext4_msg(sb, KERN_ERR,
4253                                          "bad s_min_extra_isize: %d", v);
4254                                 goto failed_mount;
4255                         }
4256                         if (sbi->s_want_extra_isize < v)
4257                                 sbi->s_want_extra_isize = v;
4258                 }
4259         }
4260
4261         if (sbi->s_es->s_mount_opts[0]) {
4262                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
4263                                               sizeof(sbi->s_es->s_mount_opts),
4264                                               GFP_KERNEL);
4265                 if (!s_mount_opts)
4266                         goto failed_mount;
4267                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
4268                                    &journal_ioprio, 0)) {
4269                         ext4_msg(sb, KERN_WARNING,
4270                                  "failed to parse options in superblock: %s",
4271                                  s_mount_opts);
4272                 }
4273                 kfree(s_mount_opts);
4274         }
4275         sbi->s_def_mount_opt = sbi->s_mount_opt;
4276         if (!parse_options((char *) data, sb, &journal_devnum,
4277                            &journal_ioprio, 0))
4278                 goto failed_mount;
4279
4280 #ifdef CONFIG_UNICODE
4281         if (ext4_has_feature_casefold(sb) && !sbi->s_encoding) {
4282                 const struct ext4_sb_encodings *encoding_info;
4283                 struct unicode_map *encoding;
4284                 __u16 encoding_flags;
4285
4286                 if (ext4_has_feature_encrypt(sb)) {
4287                         ext4_msg(sb, KERN_ERR,
4288                                  "Can't mount with encoding and encryption");
4289                         goto failed_mount;
4290                 }
4291
4292                 if (ext4_sb_read_encoding(es, &encoding_info,
4293                                           &encoding_flags)) {
4294                         ext4_msg(sb, KERN_ERR,
4295                                  "Encoding requested by superblock is unknown");
4296                         goto failed_mount;
4297                 }
4298
4299                 encoding = utf8_load(encoding_info->version);
4300                 if (IS_ERR(encoding)) {
4301                         ext4_msg(sb, KERN_ERR,
4302                                  "can't mount with superblock charset: %s-%s "
4303                                  "not supported by the kernel. flags: 0x%x.",
4304                                  encoding_info->name, encoding_info->version,
4305                                  encoding_flags);
4306                         goto failed_mount;
4307                 }
4308                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4309                          "%s-%s with flags 0x%hx", encoding_info->name,
4310                          encoding_info->version?:"\b", encoding_flags);
4311
4312                 sbi->s_encoding = encoding;
4313                 sbi->s_encoding_flags = encoding_flags;
4314         }
4315 #endif
4316
4317         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4318                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, and O_DIRECT support!\n");
4319                 /* can't mount with both data=journal and dioread_nolock. */
4320                 clear_opt(sb, DIOREAD_NOLOCK);
4321                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4322                         ext4_msg(sb, KERN_ERR, "can't mount with "
4323                                  "both data=journal and delalloc");
4324                         goto failed_mount;
4325                 }
4326                 if (test_opt(sb, DAX_ALWAYS)) {
4327                         ext4_msg(sb, KERN_ERR, "can't mount with "
4328                                  "both data=journal and dax");
4329                         goto failed_mount;
4330                 }
4331                 if (ext4_has_feature_encrypt(sb)) {
4332                         ext4_msg(sb, KERN_WARNING,
4333                                  "encrypted files will use data=ordered "
4334                                  "instead of data journaling mode");
4335                 }
4336                 if (test_opt(sb, DELALLOC))
4337                         clear_opt(sb, DELALLOC);
4338         } else {
4339                 sb->s_iflags |= SB_I_CGROUPWB;
4340         }
4341
4342         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4343                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4344
4345         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4346             (ext4_has_compat_features(sb) ||
4347              ext4_has_ro_compat_features(sb) ||
4348              ext4_has_incompat_features(sb)))
4349                 ext4_msg(sb, KERN_WARNING,
4350                        "feature flags set on rev 0 fs, "
4351                        "running e2fsck is recommended");
4352
4353         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4354                 set_opt2(sb, HURD_COMPAT);
4355                 if (ext4_has_feature_64bit(sb)) {
4356                         ext4_msg(sb, KERN_ERR,
4357                                  "The Hurd can't support 64-bit file systems");
4358                         goto failed_mount;
4359                 }
4360
4361                 /*
4362                  * ea_inode feature uses l_i_version field which is not
4363                  * available in HURD_COMPAT mode.
4364                  */
4365                 if (ext4_has_feature_ea_inode(sb)) {
4366                         ext4_msg(sb, KERN_ERR,
4367                                  "ea_inode feature is not supported for Hurd");
4368                         goto failed_mount;
4369                 }
4370         }
4371
4372         if (IS_EXT2_SB(sb)) {
4373                 if (ext2_feature_set_ok(sb))
4374                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4375                                  "using the ext4 subsystem");
4376                 else {
4377                         /*
4378                          * If we're probing be silent, if this looks like
4379                          * it's actually an ext[34] filesystem.
4380                          */
4381                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4382                                 goto failed_mount;
4383                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4384                                  "to feature incompatibilities");
4385                         goto failed_mount;
4386                 }
4387         }
4388
4389         if (IS_EXT3_SB(sb)) {
4390                 if (ext3_feature_set_ok(sb))
4391                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4392                                  "using the ext4 subsystem");
4393                 else {
4394                         /*
4395                          * If we're probing be silent, if this looks like
4396                          * it's actually an ext4 filesystem.
4397                          */
4398                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4399                                 goto failed_mount;
4400                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4401                                  "to feature incompatibilities");
4402                         goto failed_mount;
4403                 }
4404         }
4405
4406         /*
4407          * Check feature flags regardless of the revision level, since we
4408          * previously didn't change the revision level when setting the flags,
4409          * so there is a chance incompat flags are set on a rev 0 filesystem.
4410          */
4411         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4412                 goto failed_mount;
4413
4414         if (le32_to_cpu(es->s_log_block_size) >
4415             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4416                 ext4_msg(sb, KERN_ERR,
4417                          "Invalid log block size: %u",
4418                          le32_to_cpu(es->s_log_block_size));
4419                 goto failed_mount;
4420         }
4421         if (le32_to_cpu(es->s_log_cluster_size) >
4422             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4423                 ext4_msg(sb, KERN_ERR,
4424                          "Invalid log cluster size: %u",
4425                          le32_to_cpu(es->s_log_cluster_size));
4426                 goto failed_mount;
4427         }
4428
4429         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4430                 ext4_msg(sb, KERN_ERR,
4431                          "Number of reserved GDT blocks insanely large: %d",
4432                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4433                 goto failed_mount;
4434         }
4435
4436         if (bdev_dax_supported(sb->s_bdev, blocksize))
4437                 set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4438
4439         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4440                 if (ext4_has_feature_inline_data(sb)) {
4441                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4442                                         " that may contain inline data");
4443                         goto failed_mount;
4444                 }
4445                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4446                         ext4_msg(sb, KERN_ERR,
4447                                 "DAX unsupported by block device.");
4448                         goto failed_mount;
4449                 }
4450         }
4451
4452         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4453                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4454                          es->s_encryption_level);
4455                 goto failed_mount;
4456         }
4457
4458         if (sb->s_blocksize != blocksize) {
4459                 /* Validate the filesystem blocksize */
4460                 if (!sb_set_blocksize(sb, blocksize)) {
4461                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4462                                         blocksize);
4463                         goto failed_mount;
4464                 }
4465
4466                 brelse(bh);
4467                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4468                 offset = do_div(logical_sb_block, blocksize);
4469                 bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4470                 if (IS_ERR(bh)) {
4471                         ext4_msg(sb, KERN_ERR,
4472                                "Can't read superblock on 2nd try");
4473                         ret = PTR_ERR(bh);
4474                         bh = NULL;
4475                         goto failed_mount;
4476                 }
4477                 es = (struct ext4_super_block *)(bh->b_data + offset);
4478                 sbi->s_es = es;
4479                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4480                         ext4_msg(sb, KERN_ERR,
4481                                "Magic mismatch, very weird!");
4482                         goto failed_mount;
4483                 }
4484         }
4485
4486         has_huge_files = ext4_has_feature_huge_file(sb);
4487         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4488                                                       has_huge_files);
4489         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4490
4491         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4492         if (ext4_has_feature_64bit(sb)) {
4493                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4494                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4495                     !is_power_of_2(sbi->s_desc_size)) {
4496                         ext4_msg(sb, KERN_ERR,
4497                                "unsupported descriptor size %lu",
4498                                sbi->s_desc_size);
4499                         goto failed_mount;
4500                 }
4501         } else
4502                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4503
4504         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4505         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4506
4507         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4508         if (sbi->s_inodes_per_block == 0)
4509                 goto cantfind_ext4;
4510         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4511             sbi->s_inodes_per_group > blocksize * 8) {
4512                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4513                          sbi->s_inodes_per_group);
4514                 goto failed_mount;
4515         }
4516         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4517                                         sbi->s_inodes_per_block;
4518         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4519         sbi->s_sbh = bh;
4520         sbi->s_mount_state = le16_to_cpu(es->s_state);
4521         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4522         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4523
4524         for (i = 0; i < 4; i++)
4525                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4526         sbi->s_def_hash_version = es->s_def_hash_version;
4527         if (ext4_has_feature_dir_index(sb)) {
4528                 i = le32_to_cpu(es->s_flags);
4529                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4530                         sbi->s_hash_unsigned = 3;
4531                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4532 #ifdef __CHAR_UNSIGNED__
4533                         if (!sb_rdonly(sb))
4534                                 es->s_flags |=
4535                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4536                         sbi->s_hash_unsigned = 3;
4537 #else
4538                         if (!sb_rdonly(sb))
4539                                 es->s_flags |=
4540                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4541 #endif
4542                 }
4543         }
4544
4545         /* Handle clustersize */
4546         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4547         if (ext4_has_feature_bigalloc(sb)) {
4548                 if (clustersize < blocksize) {
4549                         ext4_msg(sb, KERN_ERR,
4550                                  "cluster size (%d) smaller than "
4551                                  "block size (%d)", clustersize, blocksize);
4552                         goto failed_mount;
4553                 }
4554                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4555                         le32_to_cpu(es->s_log_block_size);
4556                 sbi->s_clusters_per_group =
4557                         le32_to_cpu(es->s_clusters_per_group);
4558                 if (sbi->s_clusters_per_group > blocksize * 8) {
4559                         ext4_msg(sb, KERN_ERR,
4560                                  "#clusters per group too big: %lu",
4561                                  sbi->s_clusters_per_group);
4562                         goto failed_mount;
4563                 }
4564                 if (sbi->s_blocks_per_group !=
4565                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4566                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4567                                  "clusters per group (%lu) inconsistent",
4568                                  sbi->s_blocks_per_group,
4569                                  sbi->s_clusters_per_group);
4570                         goto failed_mount;
4571                 }
4572         } else {
4573                 if (clustersize != blocksize) {
4574                         ext4_msg(sb, KERN_ERR,
4575                                  "fragment/cluster size (%d) != "
4576                                  "block size (%d)", clustersize, blocksize);
4577                         goto failed_mount;
4578                 }
4579                 if (sbi->s_blocks_per_group > blocksize * 8) {
4580                         ext4_msg(sb, KERN_ERR,
4581                                  "#blocks per group too big: %lu",
4582                                  sbi->s_blocks_per_group);
4583                         goto failed_mount;
4584                 }
4585                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4586                 sbi->s_cluster_bits = 0;
4587         }
4588         sbi->s_cluster_ratio = clustersize / blocksize;
4589
4590         /* Do we have standard group size of clustersize * 8 blocks ? */
4591         if (sbi->s_blocks_per_group == clustersize << 3)
4592                 set_opt2(sb, STD_GROUP_SIZE);
4593
4594         /*
4595          * Test whether we have more sectors than will fit in sector_t,
4596          * and whether the max offset is addressable by the page cache.
4597          */
4598         err = generic_check_addressable(sb->s_blocksize_bits,
4599                                         ext4_blocks_count(es));
4600         if (err) {
4601                 ext4_msg(sb, KERN_ERR, "filesystem"
4602                          " too large to mount safely on this system");
4603                 goto failed_mount;
4604         }
4605
4606         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4607                 goto cantfind_ext4;
4608
4609         /* check blocks count against device size */
4610         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4611         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4612                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4613                        "exceeds size of device (%llu blocks)",
4614                        ext4_blocks_count(es), blocks_count);
4615                 goto failed_mount;
4616         }
4617
4618         /*
4619          * It makes no sense for the first data block to be beyond the end
4620          * of the filesystem.
4621          */
4622         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4623                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4624                          "block %u is beyond end of filesystem (%llu)",
4625                          le32_to_cpu(es->s_first_data_block),
4626                          ext4_blocks_count(es));
4627                 goto failed_mount;
4628         }
4629         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4630             (sbi->s_cluster_ratio == 1)) {
4631                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4632                          "block is 0 with a 1k block and cluster size");
4633                 goto failed_mount;
4634         }
4635
4636         blocks_count = (ext4_blocks_count(es) -
4637                         le32_to_cpu(es->s_first_data_block) +
4638                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4639         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4640         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4641                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4642                        "(block count %llu, first data block %u, "
4643                        "blocks per group %lu)", blocks_count,
4644                        ext4_blocks_count(es),
4645                        le32_to_cpu(es->s_first_data_block),
4646                        EXT4_BLOCKS_PER_GROUP(sb));
4647                 goto failed_mount;
4648         }
4649         sbi->s_groups_count = blocks_count;
4650         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4651                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4652         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4653             le32_to_cpu(es->s_inodes_count)) {
4654                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4655                          le32_to_cpu(es->s_inodes_count),
4656                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4657                 ret = -EINVAL;
4658                 goto failed_mount;
4659         }
4660         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4661                    EXT4_DESC_PER_BLOCK(sb);
4662         if (ext4_has_feature_meta_bg(sb)) {
4663                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4664                         ext4_msg(sb, KERN_WARNING,
4665                                  "first meta block group too large: %u "
4666                                  "(group descriptor block count %u)",
4667                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4668                         goto failed_mount;
4669                 }
4670         }
4671         rcu_assign_pointer(sbi->s_group_desc,
4672                            kvmalloc_array(db_count,
4673                                           sizeof(struct buffer_head *),
4674                                           GFP_KERNEL));
4675         if (sbi->s_group_desc == NULL) {
4676                 ext4_msg(sb, KERN_ERR, "not enough memory");
4677                 ret = -ENOMEM;
4678                 goto failed_mount;
4679         }
4680
4681         bgl_lock_init(sbi->s_blockgroup_lock);
4682
4683         /* Pre-read the descriptors into the buffer cache */
4684         for (i = 0; i < db_count; i++) {
4685                 block = descriptor_loc(sb, logical_sb_block, i);
4686                 ext4_sb_breadahead_unmovable(sb, block);
4687         }
4688
4689         for (i = 0; i < db_count; i++) {
4690                 struct buffer_head *bh;
4691
4692                 block = descriptor_loc(sb, logical_sb_block, i);
4693                 bh = ext4_sb_bread_unmovable(sb, block);
4694                 if (IS_ERR(bh)) {
4695                         ext4_msg(sb, KERN_ERR,
4696                                "can't read group descriptor %d", i);
4697                         db_count = i;
4698                         ret = PTR_ERR(bh);
4699                         bh = NULL;
4700                         goto failed_mount2;
4701                 }
4702                 rcu_read_lock();
4703                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4704                 rcu_read_unlock();
4705         }
4706         sbi->s_gdb_count = db_count;
4707         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4708                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4709                 ret = -EFSCORRUPTED;
4710                 goto failed_mount2;
4711         }
4712
4713         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4714
4715         /* Register extent status tree shrinker */
4716         if (ext4_es_register_shrinker(sbi))
4717                 goto failed_mount3;
4718
4719         sbi->s_stripe = ext4_get_stripe_size(sbi);
4720         sbi->s_extent_max_zeroout_kb = 32;
4721
4722         /*
4723          * set up enough so that it can read an inode
4724          */
4725         sb->s_op = &ext4_sops;
4726         sb->s_export_op = &ext4_export_ops;
4727         sb->s_xattr = ext4_xattr_handlers;
4728 #ifdef CONFIG_FS_ENCRYPTION
4729         sb->s_cop = &ext4_cryptops;
4730 #endif
4731 #ifdef CONFIG_FS_VERITY
4732         sb->s_vop = &ext4_verityops;
4733 #endif
4734 #ifdef CONFIG_QUOTA
4735         sb->dq_op = &ext4_quota_operations;
4736         if (ext4_has_feature_quota(sb))
4737                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4738         else
4739                 sb->s_qcop = &ext4_qctl_operations;
4740         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4741 #endif
4742         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4743
4744         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4745         mutex_init(&sbi->s_orphan_lock);
4746
4747         sb->s_root = NULL;
4748
4749         needs_recovery = (es->s_last_orphan != 0 ||
4750                           ext4_has_feature_journal_needs_recovery(sb));
4751
4752         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4753                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4754                         goto failed_mount3a;
4755
4756         /*
4757          * The first inode we look at is the journal inode.  Don't try
4758          * root first: it may be modified in the journal!
4759          */
4760         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4761                 err = ext4_load_journal(sb, es, journal_devnum);
4762                 if (err)
4763                         goto failed_mount3a;
4764         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4765                    ext4_has_feature_journal_needs_recovery(sb)) {
4766                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4767                        "suppressed and not mounted read-only");
4768                 goto failed_mount_wq;
4769         } else {
4770                 /* Nojournal mode, all journal mount options are illegal */
4771                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4772                         ext4_msg(sb, KERN_ERR, "can't mount with "
4773                                  "journal_checksum, fs mounted w/o journal");
4774                         goto failed_mount_wq;
4775                 }
4776                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4777                         ext4_msg(sb, KERN_ERR, "can't mount with "
4778                                  "journal_async_commit, fs mounted w/o journal");
4779                         goto failed_mount_wq;
4780                 }
4781                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4782                         ext4_msg(sb, KERN_ERR, "can't mount with "
4783                                  "commit=%lu, fs mounted w/o journal",
4784                                  sbi->s_commit_interval / HZ);
4785                         goto failed_mount_wq;
4786                 }
4787                 if (EXT4_MOUNT_DATA_FLAGS &
4788                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4789                         ext4_msg(sb, KERN_ERR, "can't mount with "
4790                                  "data=, fs mounted w/o journal");
4791                         goto failed_mount_wq;
4792                 }
4793                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4794                 clear_opt(sb, JOURNAL_CHECKSUM);
4795                 clear_opt(sb, DATA_FLAGS);
4796                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4797                 sbi->s_journal = NULL;
4798                 needs_recovery = 0;
4799                 goto no_journal;
4800         }
4801
4802         if (ext4_has_feature_64bit(sb) &&
4803             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4804                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4805                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4806                 goto failed_mount_wq;
4807         }
4808
4809         if (!set_journal_csum_feature_set(sb)) {
4810                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4811                          "feature set");
4812                 goto failed_mount_wq;
4813         }
4814
4815         /* We have now updated the journal if required, so we can
4816          * validate the data journaling mode. */
4817         switch (test_opt(sb, DATA_FLAGS)) {
4818         case 0:
4819                 /* No mode set, assume a default based on the journal
4820                  * capabilities: ORDERED_DATA if the journal can
4821                  * cope, else JOURNAL_DATA
4822                  */
4823                 if (jbd2_journal_check_available_features
4824                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4825                         set_opt(sb, ORDERED_DATA);
4826                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4827                 } else {
4828                         set_opt(sb, JOURNAL_DATA);
4829                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4830                 }
4831                 break;
4832
4833         case EXT4_MOUNT_ORDERED_DATA:
4834         case EXT4_MOUNT_WRITEBACK_DATA:
4835                 if (!jbd2_journal_check_available_features
4836                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4837                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4838                                "requested data journaling mode");
4839                         goto failed_mount_wq;
4840                 }
4841         default:
4842                 break;
4843         }
4844
4845         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4846             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4847                 ext4_msg(sb, KERN_ERR, "can't mount with "
4848                         "journal_async_commit in data=ordered mode");
4849                 goto failed_mount_wq;
4850         }
4851
4852         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4853
4854         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4855         sbi->s_journal->j_submit_inode_data_buffers =
4856                 ext4_journal_submit_inode_data_buffers;
4857         sbi->s_journal->j_finish_inode_data_buffers =
4858                 ext4_journal_finish_inode_data_buffers;
4859
4860 no_journal:
4861         if (!test_opt(sb, NO_MBCACHE)) {
4862                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4863                 if (!sbi->s_ea_block_cache) {
4864                         ext4_msg(sb, KERN_ERR,
4865                                  "Failed to create ea_block_cache");
4866                         goto failed_mount_wq;
4867                 }
4868
4869                 if (ext4_has_feature_ea_inode(sb)) {
4870                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4871                         if (!sbi->s_ea_inode_cache) {
4872                                 ext4_msg(sb, KERN_ERR,
4873                                          "Failed to create ea_inode_cache");
4874                                 goto failed_mount_wq;
4875                         }
4876                 }
4877         }
4878
4879         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4880                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4881                 goto failed_mount_wq;
4882         }
4883
4884         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4885             !ext4_has_feature_encrypt(sb)) {
4886                 ext4_set_feature_encrypt(sb);
4887                 ext4_commit_super(sb, 1);
4888         }
4889
4890         /*
4891          * Get the # of file system overhead blocks from the
4892          * superblock if present.
4893          */
4894         if (es->s_overhead_clusters)
4895                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4896         else {
4897                 err = ext4_calculate_overhead(sb);
4898                 if (err)
4899                         goto failed_mount_wq;
4900         }
4901
4902         /*
4903          * The maximum number of concurrent works can be high and
4904          * concurrency isn't really necessary.  Limit it to 1.
4905          */
4906         EXT4_SB(sb)->rsv_conversion_wq =
4907                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4908         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4909                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4910                 ret = -ENOMEM;
4911                 goto failed_mount4;
4912         }
4913
4914         /*
4915          * The jbd2_journal_load will have done any necessary log recovery,
4916          * so we can safely mount the rest of the filesystem now.
4917          */
4918
4919         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4920         if (IS_ERR(root)) {
4921                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4922                 ret = PTR_ERR(root);
4923                 root = NULL;
4924                 goto failed_mount4;
4925         }
4926         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4927                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4928                 iput(root);
4929                 goto failed_mount4;
4930         }
4931
4932 #ifdef CONFIG_UNICODE
4933         if (sbi->s_encoding)
4934                 sb->s_d_op = &ext4_dentry_ops;
4935 #endif
4936
4937         sb->s_root = d_make_root(root);
4938         if (!sb->s_root) {
4939                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4940                 ret = -ENOMEM;
4941                 goto failed_mount4;
4942         }
4943
4944         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4945         if (ret == -EROFS) {
4946                 sb->s_flags |= SB_RDONLY;
4947                 ret = 0;
4948         } else if (ret)
4949                 goto failed_mount4a;
4950
4951         ext4_set_resv_clusters(sb);
4952
4953         if (test_opt(sb, BLOCK_VALIDITY)) {
4954                 err = ext4_setup_system_zone(sb);
4955                 if (err) {
4956                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
4957                                  "zone (%d)", err);
4958                         goto failed_mount4a;
4959                 }
4960         }
4961
4962         ext4_ext_init(sb);
4963         err = ext4_mb_init(sb);
4964         if (err) {
4965                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4966                          err);
4967                 goto failed_mount5;
4968         }
4969
4970         block = ext4_count_free_clusters(sb);
4971         ext4_free_blocks_count_set(sbi->s_es,
4972                                    EXT4_C2B(sbi, block));
4973         ext4_superblock_csum_set(sb);
4974         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4975                                   GFP_KERNEL);
4976         if (!err) {
4977                 unsigned long freei = ext4_count_free_inodes(sb);
4978                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4979                 ext4_superblock_csum_set(sb);
4980                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4981                                           GFP_KERNEL);
4982         }
4983         if (!err)
4984                 err = percpu_counter_init(&sbi->s_dirs_counter,
4985                                           ext4_count_dirs(sb), GFP_KERNEL);
4986         if (!err)
4987                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4988                                           GFP_KERNEL);
4989         if (!err)
4990                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
4991
4992         if (err) {
4993                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4994                 goto failed_mount6;
4995         }
4996
4997         if (ext4_has_feature_flex_bg(sb))
4998                 if (!ext4_fill_flex_info(sb)) {
4999                         ext4_msg(sb, KERN_ERR,
5000                                "unable to initialize "
5001                                "flex_bg meta info!");
5002                         goto failed_mount6;
5003                 }
5004
5005         err = ext4_register_li_request(sb, first_not_zeroed);
5006         if (err)
5007                 goto failed_mount6;
5008
5009         err = ext4_register_sysfs(sb);
5010         if (err)
5011                 goto failed_mount7;
5012
5013 #ifdef CONFIG_QUOTA
5014         /* Enable quota usage during mount. */
5015         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5016                 err = ext4_enable_quotas(sb);
5017                 if (err)
5018                         goto failed_mount8;
5019         }
5020 #endif  /* CONFIG_QUOTA */
5021
5022         /*
5023          * Save the original bdev mapping's wb_err value which could be
5024          * used to detect the metadata async write error.
5025          */
5026         spin_lock_init(&sbi->s_bdev_wb_lock);
5027         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5028                                  &sbi->s_bdev_wb_err);
5029         sb->s_bdev->bd_super = sb;
5030         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5031         ext4_orphan_cleanup(sb, es);
5032         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5033         if (needs_recovery) {
5034                 ext4_msg(sb, KERN_INFO, "recovery complete");
5035                 err = ext4_mark_recovery_complete(sb, es);
5036                 if (err)
5037                         goto failed_mount8;
5038         }
5039         if (EXT4_SB(sb)->s_journal) {
5040                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5041                         descr = " journalled data mode";
5042                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5043                         descr = " ordered data mode";
5044                 else
5045                         descr = " writeback data mode";
5046         } else
5047                 descr = "out journal";
5048
5049         if (test_opt(sb, DISCARD)) {
5050                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
5051                 if (!blk_queue_discard(q))
5052                         ext4_msg(sb, KERN_WARNING,
5053                                  "mounting with \"discard\" option, but "
5054                                  "the device does not support discard");
5055         }
5056
5057         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5058                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
5059                          "Opts: %.*s%s%s", descr,
5060                          (int) sizeof(sbi->s_es->s_mount_opts),
5061                          sbi->s_es->s_mount_opts,
5062                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
5063
5064         if (es->s_error_count)
5065                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5066
5067         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5068         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5069         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5070         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5071         atomic_set(&sbi->s_warning_count, 0);
5072         atomic_set(&sbi->s_msg_count, 0);
5073
5074         kfree(orig_data);
5075         return 0;
5076
5077 cantfind_ext4:
5078         if (!silent)
5079                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5080         goto failed_mount;
5081
5082 failed_mount8:
5083         ext4_unregister_sysfs(sb);
5084         kobject_put(&sbi->s_kobj);
5085 failed_mount7:
5086         ext4_unregister_li_request(sb);
5087 failed_mount6:
5088         ext4_mb_release(sb);
5089         rcu_read_lock();
5090         flex_groups = rcu_dereference(sbi->s_flex_groups);
5091         if (flex_groups) {
5092                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
5093                         kvfree(flex_groups[i]);
5094                 kvfree(flex_groups);
5095         }
5096         rcu_read_unlock();
5097         percpu_counter_destroy(&sbi->s_freeclusters_counter);
5098         percpu_counter_destroy(&sbi->s_freeinodes_counter);
5099         percpu_counter_destroy(&sbi->s_dirs_counter);
5100         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
5101         percpu_free_rwsem(&sbi->s_writepages_rwsem);
5102 failed_mount5:
5103         ext4_ext_release(sb);
5104         ext4_release_system_zone(sb);
5105 failed_mount4a:
5106         dput(sb->s_root);
5107         sb->s_root = NULL;
5108 failed_mount4:
5109         ext4_msg(sb, KERN_ERR, "mount failed");
5110         if (EXT4_SB(sb)->rsv_conversion_wq)
5111                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5112 failed_mount_wq:
5113         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5114         sbi->s_ea_inode_cache = NULL;
5115
5116         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5117         sbi->s_ea_block_cache = NULL;
5118
5119         if (sbi->s_journal) {
5120                 jbd2_journal_destroy(sbi->s_journal);
5121                 sbi->s_journal = NULL;
5122         }
5123 failed_mount3a:
5124         ext4_es_unregister_shrinker(sbi);
5125 failed_mount3:
5126         del_timer_sync(&sbi->s_err_report);
5127         if (sbi->s_mmp_tsk)
5128                 kthread_stop(sbi->s_mmp_tsk);
5129 failed_mount2:
5130         rcu_read_lock();
5131         group_desc = rcu_dereference(sbi->s_group_desc);
5132         for (i = 0; i < db_count; i++)
5133                 brelse(group_desc[i]);
5134         kvfree(group_desc);
5135         rcu_read_unlock();
5136 failed_mount:
5137         if (sbi->s_chksum_driver)
5138                 crypto_free_shash(sbi->s_chksum_driver);
5139
5140 #ifdef CONFIG_UNICODE
5141         utf8_unload(sbi->s_encoding);
5142 #endif
5143
5144 #ifdef CONFIG_QUOTA
5145         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5146                 kfree(get_qf_name(sb, sbi, i));
5147 #endif
5148         fscrypt_free_dummy_context(&sbi->s_dummy_enc_ctx);
5149         ext4_blkdev_remove(sbi);
5150         brelse(bh);
5151 out_fail:
5152         sb->s_fs_info = NULL;
5153         kfree(sbi->s_blockgroup_lock);
5154 out_free_base:
5155         kfree(sbi);
5156         kfree(orig_data);
5157         fs_put_dax(dax_dev);
5158         return err ? err : ret;
5159 }
5160
5161 /*
5162  * Setup any per-fs journal parameters now.  We'll do this both on
5163  * initial mount, once the journal has been initialised but before we've
5164  * done any recovery; and again on any subsequent remount.
5165  */
5166 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5167 {
5168         struct ext4_sb_info *sbi = EXT4_SB(sb);
5169
5170         journal->j_commit_interval = sbi->s_commit_interval;
5171         journal->j_min_batch_time = sbi->s_min_batch_time;
5172         journal->j_max_batch_time = sbi->s_max_batch_time;
5173
5174         write_lock(&journal->j_state_lock);
5175         if (test_opt(sb, BARRIER))
5176                 journal->j_flags |= JBD2_BARRIER;
5177         else
5178                 journal->j_flags &= ~JBD2_BARRIER;
5179         if (test_opt(sb, DATA_ERR_ABORT))
5180                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5181         else
5182                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5183         write_unlock(&journal->j_state_lock);
5184 }
5185
5186 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5187                                              unsigned int journal_inum)
5188 {
5189         struct inode *journal_inode;
5190
5191         /*
5192          * Test for the existence of a valid inode on disk.  Bad things
5193          * happen if we iget() an unused inode, as the subsequent iput()
5194          * will try to delete it.
5195          */
5196         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5197         if (IS_ERR(journal_inode)) {
5198                 ext4_msg(sb, KERN_ERR, "no journal found");
5199                 return NULL;
5200         }
5201         if (!journal_inode->i_nlink) {
5202                 make_bad_inode(journal_inode);
5203                 iput(journal_inode);
5204                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5205                 return NULL;
5206         }
5207
5208         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
5209                   journal_inode, journal_inode->i_size);
5210         if (!S_ISREG(journal_inode->i_mode)) {
5211                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5212                 iput(journal_inode);
5213                 return NULL;
5214         }
5215         return journal_inode;
5216 }
5217
5218 static journal_t *ext4_get_journal(struct super_block *sb,
5219                                    unsigned int journal_inum)
5220 {
5221         struct inode *journal_inode;
5222         journal_t *journal;
5223
5224         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5225                 return NULL;
5226
5227         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5228         if (!journal_inode)
5229                 return NULL;
5230
5231         journal = jbd2_journal_init_inode(journal_inode);
5232         if (!journal) {
5233                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5234                 iput(journal_inode);
5235                 return NULL;
5236         }
5237         journal->j_private = sb;
5238         ext4_init_journal_params(sb, journal);
5239         return journal;
5240 }
5241
5242 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5243                                        dev_t j_dev)
5244 {
5245         struct buffer_head *bh;
5246         journal_t *journal;
5247         ext4_fsblk_t start;
5248         ext4_fsblk_t len;
5249         int hblock, blocksize;
5250         ext4_fsblk_t sb_block;
5251         unsigned long offset;
5252         struct ext4_super_block *es;
5253         struct block_device *bdev;
5254
5255         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5256                 return NULL;
5257
5258         bdev = ext4_blkdev_get(j_dev, sb);
5259         if (bdev == NULL)
5260                 return NULL;
5261
5262         blocksize = sb->s_blocksize;
5263         hblock = bdev_logical_block_size(bdev);
5264         if (blocksize < hblock) {
5265                 ext4_msg(sb, KERN_ERR,
5266                         "blocksize too small for journal device");
5267                 goto out_bdev;
5268         }
5269
5270         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5271         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5272         set_blocksize(bdev, blocksize);
5273         if (!(bh = __bread(bdev, sb_block, blocksize))) {
5274                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5275                        "external journal");
5276                 goto out_bdev;
5277         }
5278
5279         es = (struct ext4_super_block *) (bh->b_data + offset);
5280         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5281             !(le32_to_cpu(es->s_feature_incompat) &
5282               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5283                 ext4_msg(sb, KERN_ERR, "external journal has "
5284                                         "bad superblock");
5285                 brelse(bh);
5286                 goto out_bdev;
5287         }
5288
5289         if ((le32_to_cpu(es->s_feature_ro_compat) &
5290              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5291             es->s_checksum != ext4_superblock_csum(sb, es)) {
5292                 ext4_msg(sb, KERN_ERR, "external journal has "
5293                                        "corrupt superblock");
5294                 brelse(bh);
5295                 goto out_bdev;
5296         }
5297
5298         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5299                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5300                 brelse(bh);
5301                 goto out_bdev;
5302         }
5303
5304         len = ext4_blocks_count(es);
5305         start = sb_block + 1;
5306         brelse(bh);     /* we're done with the superblock */
5307
5308         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5309                                         start, len, blocksize);
5310         if (!journal) {
5311                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5312                 goto out_bdev;
5313         }
5314         journal->j_private = sb;
5315         if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
5316                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5317                 goto out_journal;
5318         }
5319         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5320                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5321                                         "user (unsupported) - %d",
5322                         be32_to_cpu(journal->j_superblock->s_nr_users));
5323                 goto out_journal;
5324         }
5325         EXT4_SB(sb)->s_journal_bdev = bdev;
5326         ext4_init_journal_params(sb, journal);
5327         return journal;
5328
5329 out_journal:
5330         jbd2_journal_destroy(journal);
5331 out_bdev:
5332         ext4_blkdev_put(bdev);
5333         return NULL;
5334 }
5335
5336 static int ext4_load_journal(struct super_block *sb,
5337                              struct ext4_super_block *es,
5338                              unsigned long journal_devnum)
5339 {
5340         journal_t *journal;
5341         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5342         dev_t journal_dev;
5343         int err = 0;
5344         int really_read_only;
5345         int journal_dev_ro;
5346
5347         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5348                 return -EFSCORRUPTED;
5349
5350         if (journal_devnum &&
5351             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5352                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5353                         "numbers have changed");
5354                 journal_dev = new_decode_dev(journal_devnum);
5355         } else
5356                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5357
5358         if (journal_inum && journal_dev) {
5359                 ext4_msg(sb, KERN_ERR,
5360                          "filesystem has both journal inode and journal device!");
5361                 return -EINVAL;
5362         }
5363
5364         if (journal_inum) {
5365                 journal = ext4_get_journal(sb, journal_inum);
5366                 if (!journal)
5367                         return -EINVAL;
5368         } else {
5369                 journal = ext4_get_dev_journal(sb, journal_dev);
5370                 if (!journal)
5371                         return -EINVAL;
5372         }
5373
5374         journal_dev_ro = bdev_read_only(journal->j_dev);
5375         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5376
5377         if (journal_dev_ro && !sb_rdonly(sb)) {
5378                 ext4_msg(sb, KERN_ERR,
5379                          "journal device read-only, try mounting with '-o ro'");
5380                 err = -EROFS;
5381                 goto err_out;
5382         }
5383
5384         /*
5385          * Are we loading a blank journal or performing recovery after a
5386          * crash?  For recovery, we need to check in advance whether we
5387          * can get read-write access to the device.
5388          */
5389         if (ext4_has_feature_journal_needs_recovery(sb)) {
5390                 if (sb_rdonly(sb)) {
5391                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5392                                         "required on readonly filesystem");
5393                         if (really_read_only) {
5394                                 ext4_msg(sb, KERN_ERR, "write access "
5395                                         "unavailable, cannot proceed "
5396                                         "(try mounting with noload)");
5397                                 err = -EROFS;
5398                                 goto err_out;
5399                         }
5400                         ext4_msg(sb, KERN_INFO, "write access will "
5401                                "be enabled during recovery");
5402                 }
5403         }
5404
5405         if (!(journal->j_flags & JBD2_BARRIER))
5406                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5407
5408         if (!ext4_has_feature_journal_needs_recovery(sb))
5409                 err = jbd2_journal_wipe(journal, !really_read_only);
5410         if (!err) {
5411                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5412                 if (save)
5413                         memcpy(save, ((char *) es) +
5414                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5415                 err = jbd2_journal_load(journal);
5416                 if (save)
5417                         memcpy(((char *) es) + EXT4_S_ERR_START,
5418                                save, EXT4_S_ERR_LEN);
5419                 kfree(save);
5420         }
5421
5422         if (err) {
5423                 ext4_msg(sb, KERN_ERR, "error loading journal");
5424                 goto err_out;
5425         }
5426
5427         EXT4_SB(sb)->s_journal = journal;
5428         err = ext4_clear_journal_err(sb, es);
5429         if (err) {
5430                 EXT4_SB(sb)->s_journal = NULL;
5431                 jbd2_journal_destroy(journal);
5432                 return err;
5433         }
5434
5435         if (!really_read_only && journal_devnum &&
5436             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5437                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5438
5439                 /* Make sure we flush the recovery flag to disk. */
5440                 ext4_commit_super(sb, 1);
5441         }
5442
5443         return 0;
5444
5445 err_out:
5446         jbd2_journal_destroy(journal);
5447         return err;
5448 }
5449
5450 static int ext4_commit_super(struct super_block *sb, int sync)
5451 {
5452         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
5453         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5454         int error = 0;
5455
5456         if (!sbh || block_device_ejected(sb))
5457                 return error;
5458
5459         /*
5460          * If the file system is mounted read-only, don't update the
5461          * superblock write time.  This avoids updating the superblock
5462          * write time when we are mounting the root file system
5463          * read/only but we need to replay the journal; at that point,
5464          * for people who are east of GMT and who make their clock
5465          * tick in localtime for Windows bug-for-bug compatibility,
5466          * the clock is set in the future, and this will cause e2fsck
5467          * to complain and force a full file system check.
5468          */
5469         if (!(sb->s_flags & SB_RDONLY))
5470                 ext4_update_tstamp(es, s_wtime);
5471         if (sb->s_bdev->bd_part)
5472                 es->s_kbytes_written =
5473                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5474                             ((part_stat_read(sb->s_bdev->bd_part,
5475                                              sectors[STAT_WRITE]) -
5476                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
5477         else
5478                 es->s_kbytes_written =
5479                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5480         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5481                 ext4_free_blocks_count_set(es,
5482                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5483                                 &EXT4_SB(sb)->s_freeclusters_counter)));
5484         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5485                 es->s_free_inodes_count =
5486                         cpu_to_le32(percpu_counter_sum_positive(
5487                                 &EXT4_SB(sb)->s_freeinodes_counter));
5488         BUFFER_TRACE(sbh, "marking dirty");
5489         ext4_superblock_csum_set(sb);
5490         if (sync)
5491                 lock_buffer(sbh);
5492         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5493                 /*
5494                  * Oh, dear.  A previous attempt to write the
5495                  * superblock failed.  This could happen because the
5496                  * USB device was yanked out.  Or it could happen to
5497                  * be a transient write error and maybe the block will
5498                  * be remapped.  Nothing we can do but to retry the
5499                  * write and hope for the best.
5500                  */
5501                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5502                        "superblock detected");
5503                 clear_buffer_write_io_error(sbh);
5504                 set_buffer_uptodate(sbh);
5505         }
5506         mark_buffer_dirty(sbh);
5507         if (sync) {
5508                 unlock_buffer(sbh);
5509                 error = __sync_dirty_buffer(sbh,
5510                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5511                 if (buffer_write_io_error(sbh)) {
5512                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5513                                "superblock");
5514                         clear_buffer_write_io_error(sbh);
5515                         set_buffer_uptodate(sbh);
5516                 }
5517         }
5518         return error;
5519 }
5520
5521 /*
5522  * Have we just finished recovery?  If so, and if we are mounting (or
5523  * remounting) the filesystem readonly, then we will end up with a
5524  * consistent fs on disk.  Record that fact.
5525  */
5526 static int ext4_mark_recovery_complete(struct super_block *sb,
5527                                        struct ext4_super_block *es)
5528 {
5529         int err;
5530         journal_t *journal = EXT4_SB(sb)->s_journal;
5531
5532         if (!ext4_has_feature_journal(sb)) {
5533                 if (journal != NULL) {
5534                         ext4_error(sb, "Journal got removed while the fs was "
5535                                    "mounted!");
5536                         return -EFSCORRUPTED;
5537                 }
5538                 return 0;
5539         }
5540         jbd2_journal_lock_updates(journal);
5541         err = jbd2_journal_flush(journal);
5542         if (err < 0)
5543                 goto out;
5544
5545         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5546                 ext4_clear_feature_journal_needs_recovery(sb);
5547                 ext4_commit_super(sb, 1);
5548         }
5549 out:
5550         jbd2_journal_unlock_updates(journal);
5551         return err;
5552 }
5553
5554 /*
5555  * If we are mounting (or read-write remounting) a filesystem whose journal
5556  * has recorded an error from a previous lifetime, move that error to the
5557  * main filesystem now.
5558  */
5559 static int ext4_clear_journal_err(struct super_block *sb,
5560                                    struct ext4_super_block *es)
5561 {
5562         journal_t *journal;
5563         int j_errno;
5564         const char *errstr;
5565
5566         if (!ext4_has_feature_journal(sb)) {
5567                 ext4_error(sb, "Journal got removed while the fs was mounted!");
5568                 return -EFSCORRUPTED;
5569         }
5570
5571         journal = EXT4_SB(sb)->s_journal;
5572
5573         /*
5574          * Now check for any error status which may have been recorded in the
5575          * journal by a prior ext4_error() or ext4_abort()
5576          */
5577
5578         j_errno = jbd2_journal_errno(journal);
5579         if (j_errno) {
5580                 char nbuf[16];
5581
5582                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5583                 ext4_warning(sb, "Filesystem error recorded "
5584                              "from previous mount: %s", errstr);
5585                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5586
5587                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5588                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5589                 ext4_commit_super(sb, 1);
5590
5591                 jbd2_journal_clear_err(journal);
5592                 jbd2_journal_update_sb_errno(journal);
5593         }
5594         return 0;
5595 }
5596
5597 /*
5598  * Force the running and committing transactions to commit,
5599  * and wait on the commit.
5600  */
5601 int ext4_force_commit(struct super_block *sb)
5602 {
5603         journal_t *journal;
5604
5605         if (sb_rdonly(sb))
5606                 return 0;
5607
5608         journal = EXT4_SB(sb)->s_journal;
5609         return ext4_journal_force_commit(journal);
5610 }
5611
5612 static int ext4_sync_fs(struct super_block *sb, int wait)
5613 {
5614         int ret = 0;
5615         tid_t target;
5616         bool needs_barrier = false;
5617         struct ext4_sb_info *sbi = EXT4_SB(sb);
5618
5619         if (unlikely(ext4_forced_shutdown(sbi)))
5620                 return 0;
5621
5622         trace_ext4_sync_fs(sb, wait);
5623         flush_workqueue(sbi->rsv_conversion_wq);
5624         /*
5625          * Writeback quota in non-journalled quota case - journalled quota has
5626          * no dirty dquots
5627          */
5628         dquot_writeback_dquots(sb, -1);
5629         /*
5630          * Data writeback is possible w/o journal transaction, so barrier must
5631          * being sent at the end of the function. But we can skip it if
5632          * transaction_commit will do it for us.
5633          */
5634         if (sbi->s_journal) {
5635                 target = jbd2_get_latest_transaction(sbi->s_journal);
5636                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5637                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5638                         needs_barrier = true;
5639
5640                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5641                         if (wait)
5642                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5643                                                            target);
5644                 }
5645         } else if (wait && test_opt(sb, BARRIER))
5646                 needs_barrier = true;
5647         if (needs_barrier) {
5648                 int err;
5649                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL);
5650                 if (!ret)
5651                         ret = err;
5652         }
5653
5654         return ret;
5655 }
5656
5657 /*
5658  * LVM calls this function before a (read-only) snapshot is created.  This
5659  * gives us a chance to flush the journal completely and mark the fs clean.
5660  *
5661  * Note that only this function cannot bring a filesystem to be in a clean
5662  * state independently. It relies on upper layer to stop all data & metadata
5663  * modifications.
5664  */
5665 static int ext4_freeze(struct super_block *sb)
5666 {
5667         int error = 0;
5668         journal_t *journal;
5669
5670         if (sb_rdonly(sb))
5671                 return 0;
5672
5673         journal = EXT4_SB(sb)->s_journal;
5674
5675         if (journal) {
5676                 /* Now we set up the journal barrier. */
5677                 jbd2_journal_lock_updates(journal);
5678
5679                 /*
5680                  * Don't clear the needs_recovery flag if we failed to
5681                  * flush the journal.
5682                  */
5683                 error = jbd2_journal_flush(journal);
5684                 if (error < 0)
5685                         goto out;
5686
5687                 /* Journal blocked and flushed, clear needs_recovery flag. */
5688                 ext4_clear_feature_journal_needs_recovery(sb);
5689         }
5690
5691         error = ext4_commit_super(sb, 1);
5692 out:
5693         if (journal)
5694                 /* we rely on upper layer to stop further updates */
5695                 jbd2_journal_unlock_updates(journal);
5696         return error;
5697 }
5698
5699 /*
5700  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5701  * flag here, even though the filesystem is not technically dirty yet.
5702  */
5703 static int ext4_unfreeze(struct super_block *sb)
5704 {
5705         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5706                 return 0;
5707
5708         if (EXT4_SB(sb)->s_journal) {
5709                 /* Reset the needs_recovery flag before the fs is unlocked. */
5710                 ext4_set_feature_journal_needs_recovery(sb);
5711         }
5712
5713         ext4_commit_super(sb, 1);
5714         return 0;
5715 }
5716
5717 /*
5718  * Structure to save mount options for ext4_remount's benefit
5719  */
5720 struct ext4_mount_options {
5721         unsigned long s_mount_opt;
5722         unsigned long s_mount_opt2;
5723         kuid_t s_resuid;
5724         kgid_t s_resgid;
5725         unsigned long s_commit_interval;
5726         u32 s_min_batch_time, s_max_batch_time;
5727 #ifdef CONFIG_QUOTA
5728         int s_jquota_fmt;
5729         char *s_qf_names[EXT4_MAXQUOTAS];
5730 #endif
5731 };
5732
5733 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5734 {
5735         struct ext4_super_block *es;
5736         struct ext4_sb_info *sbi = EXT4_SB(sb);
5737         unsigned long old_sb_flags, vfs_flags;
5738         struct ext4_mount_options old_opts;
5739         int enable_quota = 0;
5740         ext4_group_t g;
5741         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5742         int err = 0;
5743 #ifdef CONFIG_QUOTA
5744         int i, j;
5745         char *to_free[EXT4_MAXQUOTAS];
5746 #endif
5747         char *orig_data = kstrdup(data, GFP_KERNEL);
5748
5749         if (data && !orig_data)
5750                 return -ENOMEM;
5751
5752         /* Store the original options */
5753         old_sb_flags = sb->s_flags;
5754         old_opts.s_mount_opt = sbi->s_mount_opt;
5755         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5756         old_opts.s_resuid = sbi->s_resuid;
5757         old_opts.s_resgid = sbi->s_resgid;
5758         old_opts.s_commit_interval = sbi->s_commit_interval;
5759         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5760         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5761 #ifdef CONFIG_QUOTA
5762         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5763         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5764                 if (sbi->s_qf_names[i]) {
5765                         char *qf_name = get_qf_name(sb, sbi, i);
5766
5767                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5768                         if (!old_opts.s_qf_names[i]) {
5769                                 for (j = 0; j < i; j++)
5770                                         kfree(old_opts.s_qf_names[j]);
5771                                 kfree(orig_data);
5772                                 return -ENOMEM;
5773                         }
5774                 } else
5775                         old_opts.s_qf_names[i] = NULL;
5776 #endif
5777         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5778                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5779
5780         /*
5781          * Some options can be enabled by ext4 and/or by VFS mount flag
5782          * either way we need to make sure it matches in both *flags and
5783          * s_flags. Copy those selected flags from *flags to s_flags
5784          */
5785         vfs_flags = SB_LAZYTIME | SB_I_VERSION;
5786         sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags);
5787
5788         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5789                 err = -EINVAL;
5790                 goto restore_opts;
5791         }
5792
5793         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5794             test_opt(sb, JOURNAL_CHECKSUM)) {
5795                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5796                          "during remount not supported; ignoring");
5797                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5798         }
5799
5800         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5801                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5802                         ext4_msg(sb, KERN_ERR, "can't mount with "
5803                                  "both data=journal and delalloc");
5804                         err = -EINVAL;
5805                         goto restore_opts;
5806                 }
5807                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5808                         ext4_msg(sb, KERN_ERR, "can't mount with "
5809                                  "both data=journal and dioread_nolock");
5810                         err = -EINVAL;
5811                         goto restore_opts;
5812                 }
5813         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5814                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5815                         ext4_msg(sb, KERN_ERR, "can't mount with "
5816                                 "journal_async_commit in data=ordered mode");
5817                         err = -EINVAL;
5818                         goto restore_opts;
5819                 }
5820         }
5821
5822         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5823                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5824                 err = -EINVAL;
5825                 goto restore_opts;
5826         }
5827
5828         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5829                 ext4_abort(sb, EXT4_ERR_ESHUTDOWN, "Abort forced by user");
5830
5831         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5832                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5833
5834         es = sbi->s_es;
5835
5836         if (sbi->s_journal) {
5837                 ext4_init_journal_params(sb, sbi->s_journal);
5838                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5839         }
5840
5841         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5842                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5843                         err = -EROFS;
5844                         goto restore_opts;
5845                 }
5846
5847                 if (*flags & SB_RDONLY) {
5848                         err = sync_filesystem(sb);
5849                         if (err < 0)
5850                                 goto restore_opts;
5851                         err = dquot_suspend(sb, -1);
5852                         if (err < 0)
5853                                 goto restore_opts;
5854
5855                         /*
5856                          * First of all, the unconditional stuff we have to do
5857                          * to disable replay of the journal when we next remount
5858                          */
5859                         sb->s_flags |= SB_RDONLY;
5860
5861                         /*
5862                          * OK, test if we are remounting a valid rw partition
5863                          * readonly, and if so set the rdonly flag and then
5864                          * mark the partition as valid again.
5865                          */
5866                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5867                             (sbi->s_mount_state & EXT4_VALID_FS))
5868                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5869
5870                         if (sbi->s_journal) {
5871                                 /*
5872                                  * We let remount-ro finish even if marking fs
5873                                  * as clean failed...
5874                                  */
5875                                 ext4_mark_recovery_complete(sb, es);
5876                         }
5877                         if (sbi->s_mmp_tsk)
5878                                 kthread_stop(sbi->s_mmp_tsk);
5879                 } else {
5880                         /* Make sure we can mount this feature set readwrite */
5881                         if (ext4_has_feature_readonly(sb) ||
5882                             !ext4_feature_set_ok(sb, 0)) {
5883                                 err = -EROFS;
5884                                 goto restore_opts;
5885                         }
5886                         /*
5887                          * Make sure the group descriptor checksums
5888                          * are sane.  If they aren't, refuse to remount r/w.
5889                          */
5890                         for (g = 0; g < sbi->s_groups_count; g++) {
5891                                 struct ext4_group_desc *gdp =
5892                                         ext4_get_group_desc(sb, g, NULL);
5893
5894                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5895                                         ext4_msg(sb, KERN_ERR,
5896                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5897                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5898                                                le16_to_cpu(gdp->bg_checksum));
5899                                         err = -EFSBADCRC;
5900                                         goto restore_opts;
5901                                 }
5902                         }
5903
5904                         /*
5905                          * If we have an unprocessed orphan list hanging
5906                          * around from a previously readonly bdev mount,
5907                          * require a full umount/remount for now.
5908                          */
5909                         if (es->s_last_orphan) {
5910                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5911                                        "remount RDWR because of unprocessed "
5912                                        "orphan inode list.  Please "
5913                                        "umount/remount instead");
5914                                 err = -EINVAL;
5915                                 goto restore_opts;
5916                         }
5917
5918                         /*
5919                          * Mounting a RDONLY partition read-write, so reread
5920                          * and store the current valid flag.  (It may have
5921                          * been changed by e2fsck since we originally mounted
5922                          * the partition.)
5923                          */
5924                         if (sbi->s_journal) {
5925                                 err = ext4_clear_journal_err(sb, es);
5926                                 if (err)
5927                                         goto restore_opts;
5928                         }
5929                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5930
5931                         err = ext4_setup_super(sb, es, 0);
5932                         if (err)
5933                                 goto restore_opts;
5934
5935                         sb->s_flags &= ~SB_RDONLY;
5936                         if (ext4_has_feature_mmp(sb))
5937                                 if (ext4_multi_mount_protect(sb,
5938                                                 le64_to_cpu(es->s_mmp_block))) {
5939                                         err = -EROFS;
5940                                         goto restore_opts;
5941                                 }
5942                         enable_quota = 1;
5943                 }
5944         }
5945
5946         /*
5947          * Reinitialize lazy itable initialization thread based on
5948          * current settings
5949          */
5950         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5951                 ext4_unregister_li_request(sb);
5952         else {
5953                 ext4_group_t first_not_zeroed;
5954                 first_not_zeroed = ext4_has_uninit_itable(sb);
5955                 ext4_register_li_request(sb, first_not_zeroed);
5956         }
5957
5958         /*
5959          * Handle creation of system zone data early because it can fail.
5960          * Releasing of existing data is done when we are sure remount will
5961          * succeed.
5962          */
5963         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
5964                 err = ext4_setup_system_zone(sb);
5965                 if (err)
5966                         goto restore_opts;
5967         }
5968
5969         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5970                 err = ext4_commit_super(sb, 1);
5971                 if (err)
5972                         goto restore_opts;
5973         }
5974
5975 #ifdef CONFIG_QUOTA
5976         /* Release old quota file names */
5977         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5978                 kfree(old_opts.s_qf_names[i]);
5979         if (enable_quota) {
5980                 if (sb_any_quota_suspended(sb))
5981                         dquot_resume(sb, -1);
5982                 else if (ext4_has_feature_quota(sb)) {
5983                         err = ext4_enable_quotas(sb);
5984                         if (err)
5985                                 goto restore_opts;
5986                 }
5987         }
5988 #endif
5989         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
5990                 ext4_release_system_zone(sb);
5991
5992         /*
5993          * Some options can be enabled by ext4 and/or by VFS mount flag
5994          * either way we need to make sure it matches in both *flags and
5995          * s_flags. Copy those selected flags from s_flags to *flags
5996          */
5997         *flags = (*flags & ~vfs_flags) | (sb->s_flags & vfs_flags);
5998
5999         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
6000         kfree(orig_data);
6001         return 0;
6002
6003 restore_opts:
6004         sb->s_flags = old_sb_flags;
6005         sbi->s_mount_opt = old_opts.s_mount_opt;
6006         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6007         sbi->s_resuid = old_opts.s_resuid;
6008         sbi->s_resgid = old_opts.s_resgid;
6009         sbi->s_commit_interval = old_opts.s_commit_interval;
6010         sbi->s_min_batch_time = old_opts.s_min_batch_time;
6011         sbi->s_max_batch_time = old_opts.s_max_batch_time;
6012         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6013                 ext4_release_system_zone(sb);
6014 #ifdef CONFIG_QUOTA
6015         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6016         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6017                 to_free[i] = get_qf_name(sb, sbi, i);
6018                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6019         }
6020         synchronize_rcu();
6021         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6022                 kfree(to_free[i]);
6023 #endif
6024         kfree(orig_data);
6025         return err;
6026 }
6027
6028 #ifdef CONFIG_QUOTA
6029 static int ext4_statfs_project(struct super_block *sb,
6030                                kprojid_t projid, struct kstatfs *buf)
6031 {
6032         struct kqid qid;
6033         struct dquot *dquot;
6034         u64 limit;
6035         u64 curblock;
6036
6037         qid = make_kqid_projid(projid);
6038         dquot = dqget(sb, qid);
6039         if (IS_ERR(dquot))
6040                 return PTR_ERR(dquot);
6041         spin_lock(&dquot->dq_dqb_lock);
6042
6043         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6044                              dquot->dq_dqb.dqb_bhardlimit);
6045         limit >>= sb->s_blocksize_bits;
6046
6047         if (limit && buf->f_blocks > limit) {
6048                 curblock = (dquot->dq_dqb.dqb_curspace +
6049                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6050                 buf->f_blocks = limit;
6051                 buf->f_bfree = buf->f_bavail =
6052                         (buf->f_blocks > curblock) ?
6053                          (buf->f_blocks - curblock) : 0;
6054         }
6055
6056         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6057                              dquot->dq_dqb.dqb_ihardlimit);
6058         if (limit && buf->f_files > limit) {
6059                 buf->f_files = limit;
6060                 buf->f_ffree =
6061                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6062                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6063         }
6064
6065         spin_unlock(&dquot->dq_dqb_lock);
6066         dqput(dquot);
6067         return 0;
6068 }
6069 #endif
6070
6071 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6072 {
6073         struct super_block *sb = dentry->d_sb;
6074         struct ext4_sb_info *sbi = EXT4_SB(sb);
6075         struct ext4_super_block *es = sbi->s_es;
6076         ext4_fsblk_t overhead = 0, resv_blocks;
6077         u64 fsid;
6078         s64 bfree;
6079         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6080
6081         if (!test_opt(sb, MINIX_DF))
6082                 overhead = sbi->s_overhead;
6083
6084         buf->f_type = EXT4_SUPER_MAGIC;
6085         buf->f_bsize = sb->s_blocksize;
6086         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6087         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6088                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6089         /* prevent underflow in case that few free space is available */
6090         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6091         buf->f_bavail = buf->f_bfree -
6092                         (ext4_r_blocks_count(es) + resv_blocks);
6093         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6094                 buf->f_bavail = 0;
6095         buf->f_files = le32_to_cpu(es->s_inodes_count);
6096         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6097         buf->f_namelen = EXT4_NAME_LEN;
6098         fsid = le64_to_cpup((void *)es->s_uuid) ^
6099                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
6100         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
6101         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
6102
6103 #ifdef CONFIG_QUOTA
6104         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6105             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6106                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6107 #endif
6108         return 0;
6109 }
6110
6111
6112 #ifdef CONFIG_QUOTA
6113
6114 /*
6115  * Helper functions so that transaction is started before we acquire dqio_sem
6116  * to keep correct lock ordering of transaction > dqio_sem
6117  */
6118 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6119 {
6120         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6121 }
6122
6123 static int ext4_write_dquot(struct dquot *dquot)
6124 {
6125         int ret, err;
6126         handle_t *handle;
6127         struct inode *inode;
6128
6129         inode = dquot_to_inode(dquot);
6130         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6131                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6132         if (IS_ERR(handle))
6133                 return PTR_ERR(handle);
6134         ret = dquot_commit(dquot);
6135         err = ext4_journal_stop(handle);
6136         if (!ret)
6137                 ret = err;
6138         return ret;
6139 }
6140
6141 static int ext4_acquire_dquot(struct dquot *dquot)
6142 {
6143         int ret, err;
6144         handle_t *handle;
6145
6146         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6147                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6148         if (IS_ERR(handle))
6149                 return PTR_ERR(handle);
6150         ret = dquot_acquire(dquot);
6151         err = ext4_journal_stop(handle);
6152         if (!ret)
6153                 ret = err;
6154         return ret;
6155 }
6156
6157 static int ext4_release_dquot(struct dquot *dquot)
6158 {
6159         int ret, err;
6160         handle_t *handle;
6161
6162         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6163                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6164         if (IS_ERR(handle)) {
6165                 /* Release dquot anyway to avoid endless cycle in dqput() */
6166                 dquot_release(dquot);
6167                 return PTR_ERR(handle);
6168         }
6169         ret = dquot_release(dquot);
6170         err = ext4_journal_stop(handle);
6171         if (!ret)
6172                 ret = err;
6173         return ret;
6174 }
6175
6176 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6177 {
6178         struct super_block *sb = dquot->dq_sb;
6179         struct ext4_sb_info *sbi = EXT4_SB(sb);
6180
6181         /* Are we journaling quotas? */
6182         if (ext4_has_feature_quota(sb) ||
6183             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
6184                 dquot_mark_dquot_dirty(dquot);
6185                 return ext4_write_dquot(dquot);
6186         } else {
6187                 return dquot_mark_dquot_dirty(dquot);
6188         }
6189 }
6190
6191 static int ext4_write_info(struct super_block *sb, int type)
6192 {
6193         int ret, err;
6194         handle_t *handle;
6195
6196         /* Data block + inode block */
6197         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
6198         if (IS_ERR(handle))
6199                 return PTR_ERR(handle);
6200         ret = dquot_commit_info(sb, type);
6201         err = ext4_journal_stop(handle);
6202         if (!ret)
6203                 ret = err;
6204         return ret;
6205 }
6206
6207 /*
6208  * Turn on quotas during mount time - we need to find
6209  * the quota file and such...
6210  */
6211 static int ext4_quota_on_mount(struct super_block *sb, int type)
6212 {
6213         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
6214                                         EXT4_SB(sb)->s_jquota_fmt, type);
6215 }
6216
6217 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6218 {
6219         struct ext4_inode_info *ei = EXT4_I(inode);
6220
6221         /* The first argument of lockdep_set_subclass has to be
6222          * *exactly* the same as the argument to init_rwsem() --- in
6223          * this case, in init_once() --- or lockdep gets unhappy
6224          * because the name of the lock is set using the
6225          * stringification of the argument to init_rwsem().
6226          */
6227         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6228         lockdep_set_subclass(&ei->i_data_sem, subclass);
6229 }
6230
6231 /*
6232  * Standard function to be called on quota_on
6233  */
6234 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6235                          const struct path *path)
6236 {
6237         int err;
6238
6239         if (!test_opt(sb, QUOTA))
6240                 return -EINVAL;
6241
6242         /* Quotafile not on the same filesystem? */
6243         if (path->dentry->d_sb != sb)
6244                 return -EXDEV;
6245
6246         /* Quota already enabled for this file? */
6247         if (IS_NOQUOTA(d_inode(path->dentry)))
6248                 return -EBUSY;
6249
6250         /* Journaling quota? */
6251         if (EXT4_SB(sb)->s_qf_names[type]) {
6252                 /* Quotafile not in fs root? */
6253                 if (path->dentry->d_parent != sb->s_root)
6254                         ext4_msg(sb, KERN_WARNING,
6255                                 "Quota file not on filesystem root. "
6256                                 "Journaled quota will not work");
6257                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6258         } else {
6259                 /*
6260                  * Clear the flag just in case mount options changed since
6261                  * last time.
6262                  */
6263                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6264         }
6265
6266         /*
6267          * When we journal data on quota file, we have to flush journal to see
6268          * all updates to the file when we bypass pagecache...
6269          */
6270         if (EXT4_SB(sb)->s_journal &&
6271             ext4_should_journal_data(d_inode(path->dentry))) {
6272                 /*
6273                  * We don't need to lock updates but journal_flush() could
6274                  * otherwise be livelocked...
6275                  */
6276                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6277                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
6278                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6279                 if (err)
6280                         return err;
6281         }
6282
6283         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6284         err = dquot_quota_on(sb, type, format_id, path);
6285         if (err) {
6286                 lockdep_set_quota_inode(path->dentry->d_inode,
6287                                              I_DATA_SEM_NORMAL);
6288         } else {
6289                 struct inode *inode = d_inode(path->dentry);
6290                 handle_t *handle;
6291
6292                 /*
6293                  * Set inode flags to prevent userspace from messing with quota
6294                  * files. If this fails, we return success anyway since quotas
6295                  * are already enabled and this is not a hard failure.
6296                  */
6297                 inode_lock(inode);
6298                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6299                 if (IS_ERR(handle))
6300                         goto unlock_inode;
6301                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6302                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6303                                 S_NOATIME | S_IMMUTABLE);
6304                 err = ext4_mark_inode_dirty(handle, inode);
6305                 ext4_journal_stop(handle);
6306         unlock_inode:
6307                 inode_unlock(inode);
6308         }
6309         return err;
6310 }
6311
6312 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6313                              unsigned int flags)
6314 {
6315         int err;
6316         struct inode *qf_inode;
6317         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6318                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6319                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6320                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6321         };
6322
6323         BUG_ON(!ext4_has_feature_quota(sb));
6324
6325         if (!qf_inums[type])
6326                 return -EPERM;
6327
6328         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6329         if (IS_ERR(qf_inode)) {
6330                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6331                 return PTR_ERR(qf_inode);
6332         }
6333
6334         /* Don't account quota for quota files to avoid recursion */
6335         qf_inode->i_flags |= S_NOQUOTA;
6336         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6337         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6338         if (err)
6339                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6340         iput(qf_inode);
6341
6342         return err;
6343 }
6344
6345 /* Enable usage tracking for all quota types. */
6346 static int ext4_enable_quotas(struct super_block *sb)
6347 {
6348         int type, err = 0;
6349         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6350                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6351                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6352                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6353         };
6354         bool quota_mopt[EXT4_MAXQUOTAS] = {
6355                 test_opt(sb, USRQUOTA),
6356                 test_opt(sb, GRPQUOTA),
6357                 test_opt(sb, PRJQUOTA),
6358         };
6359
6360         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6361         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6362                 if (qf_inums[type]) {
6363                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6364                                 DQUOT_USAGE_ENABLED |
6365                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6366                         if (err) {
6367                                 ext4_warning(sb,
6368                                         "Failed to enable quota tracking "
6369                                         "(type=%d, err=%d). Please run "
6370                                         "e2fsck to fix.", type, err);
6371                                 for (type--; type >= 0; type--)
6372                                         dquot_quota_off(sb, type);
6373
6374                                 return err;
6375                         }
6376                 }
6377         }
6378         return 0;
6379 }
6380
6381 static int ext4_quota_off(struct super_block *sb, int type)
6382 {
6383         struct inode *inode = sb_dqopt(sb)->files[type];
6384         handle_t *handle;
6385         int err;
6386
6387         /* Force all delayed allocation blocks to be allocated.
6388          * Caller already holds s_umount sem */
6389         if (test_opt(sb, DELALLOC))
6390                 sync_filesystem(sb);
6391
6392         if (!inode || !igrab(inode))
6393                 goto out;
6394
6395         err = dquot_quota_off(sb, type);
6396         if (err || ext4_has_feature_quota(sb))
6397                 goto out_put;
6398
6399         inode_lock(inode);
6400         /*
6401          * Update modification times of quota files when userspace can
6402          * start looking at them. If we fail, we return success anyway since
6403          * this is not a hard failure and quotas are already disabled.
6404          */
6405         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6406         if (IS_ERR(handle)) {
6407                 err = PTR_ERR(handle);
6408                 goto out_unlock;
6409         }
6410         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6411         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6412         inode->i_mtime = inode->i_ctime = current_time(inode);
6413         err = ext4_mark_inode_dirty(handle, inode);
6414         ext4_journal_stop(handle);
6415 out_unlock:
6416         inode_unlock(inode);
6417 out_put:
6418         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6419         iput(inode);
6420         return err;
6421 out:
6422         return dquot_quota_off(sb, type);
6423 }
6424
6425 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6426  * acquiring the locks... As quota files are never truncated and quota code
6427  * itself serializes the operations (and no one else should touch the files)
6428  * we don't have to be afraid of races */
6429 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6430                                size_t len, loff_t off)
6431 {
6432         struct inode *inode = sb_dqopt(sb)->files[type];
6433         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6434         int offset = off & (sb->s_blocksize - 1);
6435         int tocopy;
6436         size_t toread;
6437         struct buffer_head *bh;
6438         loff_t i_size = i_size_read(inode);
6439
6440         if (off > i_size)
6441                 return 0;
6442         if (off+len > i_size)
6443                 len = i_size-off;
6444         toread = len;
6445         while (toread > 0) {
6446                 tocopy = sb->s_blocksize - offset < toread ?
6447                                 sb->s_blocksize - offset : toread;
6448                 bh = ext4_bread(NULL, inode, blk, 0);
6449                 if (IS_ERR(bh))
6450                         return PTR_ERR(bh);
6451                 if (!bh)        /* A hole? */
6452                         memset(data, 0, tocopy);
6453                 else
6454                         memcpy(data, bh->b_data+offset, tocopy);
6455                 brelse(bh);
6456                 offset = 0;
6457                 toread -= tocopy;
6458                 data += tocopy;
6459                 blk++;
6460         }
6461         return len;
6462 }
6463
6464 /* Write to quotafile (we know the transaction is already started and has
6465  * enough credits) */
6466 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6467                                 const char *data, size_t len, loff_t off)
6468 {
6469         struct inode *inode = sb_dqopt(sb)->files[type];
6470         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6471         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6472         int retries = 0;
6473         struct buffer_head *bh;
6474         handle_t *handle = journal_current_handle();
6475
6476         if (EXT4_SB(sb)->s_journal && !handle) {
6477                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6478                         " cancelled because transaction is not started",
6479                         (unsigned long long)off, (unsigned long long)len);
6480                 return -EIO;
6481         }
6482         /*
6483          * Since we account only one data block in transaction credits,
6484          * then it is impossible to cross a block boundary.
6485          */
6486         if (sb->s_blocksize - offset < len) {
6487                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6488                         " cancelled because not block aligned",
6489                         (unsigned long long)off, (unsigned long long)len);
6490                 return -EIO;
6491         }
6492
6493         do {
6494                 bh = ext4_bread(handle, inode, blk,
6495                                 EXT4_GET_BLOCKS_CREATE |
6496                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6497         } while (PTR_ERR(bh) == -ENOSPC &&
6498                  ext4_should_retry_alloc(inode->i_sb, &retries));
6499         if (IS_ERR(bh))
6500                 return PTR_ERR(bh);
6501         if (!bh)
6502                 goto out;
6503         BUFFER_TRACE(bh, "get write access");
6504         err = ext4_journal_get_write_access(handle, bh);
6505         if (err) {
6506                 brelse(bh);
6507                 return err;
6508         }
6509         lock_buffer(bh);
6510         memcpy(bh->b_data+offset, data, len);
6511         flush_dcache_page(bh->b_page);
6512         unlock_buffer(bh);
6513         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6514         brelse(bh);
6515 out:
6516         if (inode->i_size < off + len) {
6517                 i_size_write(inode, off + len);
6518                 EXT4_I(inode)->i_disksize = inode->i_size;
6519                 err2 = ext4_mark_inode_dirty(handle, inode);
6520                 if (unlikely(err2 && !err))
6521                         err = err2;
6522         }
6523         return err ? err : len;
6524 }
6525 #endif
6526
6527 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6528                        const char *dev_name, void *data)
6529 {
6530         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6531 }
6532
6533 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6534 static inline void register_as_ext2(void)
6535 {
6536         int err = register_filesystem(&ext2_fs_type);
6537         if (err)
6538                 printk(KERN_WARNING
6539                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6540 }
6541
6542 static inline void unregister_as_ext2(void)
6543 {
6544         unregister_filesystem(&ext2_fs_type);
6545 }
6546
6547 static inline int ext2_feature_set_ok(struct super_block *sb)
6548 {
6549         if (ext4_has_unknown_ext2_incompat_features(sb))
6550                 return 0;
6551         if (sb_rdonly(sb))
6552                 return 1;
6553         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6554                 return 0;
6555         return 1;
6556 }
6557 #else
6558 static inline void register_as_ext2(void) { }
6559 static inline void unregister_as_ext2(void) { }
6560 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6561 #endif
6562
6563 static inline void register_as_ext3(void)
6564 {
6565         int err = register_filesystem(&ext3_fs_type);
6566         if (err)
6567                 printk(KERN_WARNING
6568                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6569 }
6570
6571 static inline void unregister_as_ext3(void)
6572 {
6573         unregister_filesystem(&ext3_fs_type);
6574 }
6575
6576 static inline int ext3_feature_set_ok(struct super_block *sb)
6577 {
6578         if (ext4_has_unknown_ext3_incompat_features(sb))
6579                 return 0;
6580         if (!ext4_has_feature_journal(sb))
6581                 return 0;
6582         if (sb_rdonly(sb))
6583                 return 1;
6584         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6585                 return 0;
6586         return 1;
6587 }
6588
6589 static struct file_system_type ext4_fs_type = {
6590         .owner          = THIS_MODULE,
6591         .name           = "ext4",
6592         .mount          = ext4_mount,
6593         .kill_sb        = kill_block_super,
6594         .fs_flags       = FS_REQUIRES_DEV,
6595 };
6596 MODULE_ALIAS_FS("ext4");
6597
6598 /* Shared across all ext4 file systems */
6599 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6600
6601 static int __init ext4_init_fs(void)
6602 {
6603         int i, err;
6604
6605         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6606         ext4_li_info = NULL;
6607         mutex_init(&ext4_li_mtx);
6608
6609         /* Build-time check for flags consistency */
6610         ext4_check_flag_values();
6611
6612         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6613                 init_waitqueue_head(&ext4__ioend_wq[i]);
6614
6615         err = ext4_init_es();
6616         if (err)
6617                 return err;
6618
6619         err = ext4_init_pending();
6620         if (err)
6621                 goto out7;
6622
6623         err = ext4_init_post_read_processing();
6624         if (err)
6625                 goto out6;
6626
6627         err = ext4_init_pageio();
6628         if (err)
6629                 goto out5;
6630
6631         err = ext4_init_system_zone();
6632         if (err)
6633                 goto out4;
6634
6635         err = ext4_init_sysfs();
6636         if (err)
6637                 goto out3;
6638
6639         err = ext4_init_mballoc();
6640         if (err)
6641                 goto out2;
6642         err = init_inodecache();
6643         if (err)
6644                 goto out1;
6645         register_as_ext3();
6646         register_as_ext2();
6647         err = register_filesystem(&ext4_fs_type);
6648         if (err)
6649                 goto out;
6650
6651         return 0;
6652 out:
6653         unregister_as_ext2();
6654         unregister_as_ext3();
6655         destroy_inodecache();
6656 out1:
6657         ext4_exit_mballoc();
6658 out2:
6659         ext4_exit_sysfs();
6660 out3:
6661         ext4_exit_system_zone();
6662 out4:
6663         ext4_exit_pageio();
6664 out5:
6665         ext4_exit_post_read_processing();
6666 out6:
6667         ext4_exit_pending();
6668 out7:
6669         ext4_exit_es();
6670
6671         return err;
6672 }
6673
6674 static void __exit ext4_exit_fs(void)
6675 {
6676         ext4_destroy_lazyinit_thread();
6677         unregister_as_ext2();
6678         unregister_as_ext3();
6679         unregister_filesystem(&ext4_fs_type);
6680         destroy_inodecache();
6681         ext4_exit_mballoc();
6682         ext4_exit_sysfs();
6683         ext4_exit_system_zone();
6684         ext4_exit_pageio();
6685         ext4_exit_post_read_processing();
6686         ext4_exit_es();
6687         ext4_exit_pending();
6688 }
6689
6690 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6691 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6692 MODULE_LICENSE("GPL");
6693 MODULE_SOFTDEP("pre: crc32c");
6694 module_init(ext4_init_fs)
6695 module_exit(ext4_exit_fs)