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 ([email protected])
   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 ([email protected]), 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
  46 #include <linux/kthread.h>
  47 #include <linux/freezer.h>
  48
  49 #include "ext4.h"
  50 #include "ext4_extents.h"       /* Needed for trace points definition */
  51 #include "ext4_jbd2.h"
  52 #include "xattr.h"
  53 #include "acl.h"
  54 #include "mballoc.h"
  55 #include "fsmap.h"
  56
  57 #define CREATE_TRACE_POINTS
  58 #include <trace/events/ext4.h>
  59
  60 static struct ext4_lazy_init *ext4_li_info;
  61 static struct mutex ext4_li_mtx;
  62 static struct ratelimit_state ext4_mount_msg_ratelimit;
  63
  64 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  65                              unsigned long journal_devnum);
  66 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  67 static int ext4_commit_super(struct super_block *sb, int sync);
  68 static void ext4_mark_recovery_complete(struct super_block *sb,
  69                                         struct ext4_super_block *es);
  70 static void ext4_clear_journal_err(struct super_block *sb,
  71                                    struct ext4_super_block *es);
  72 static int ext4_sync_fs(struct super_block *sb, int wait);
  73 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  74 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  75 static int ext4_unfreeze(struct super_block *sb);
  76 static int ext4_freeze(struct super_block *sb);
  77 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  78                        const char *dev_name, void *data);
  79 static inline int ext2_feature_set_ok(struct super_block *sb);
  80 static inline int ext3_feature_set_ok(struct super_block *sb);
  81 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  82 static void ext4_destroy_lazyinit_thread(void);
  83 static void ext4_unregister_li_request(struct super_block *sb);
  84 static void ext4_clear_request_list(void);
  85 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  86                                             unsigned int journal_inum);
  87
  88 /*
  89  * Lock ordering
  90  *
  91  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
  92  * i_mmap_rwsem (inode->i_mmap_rwsem)!
  93  *
  94  * page fault path:
  95  * mmap_sem -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
  96  *   page lock -> i_data_sem (rw)
  97  *
  98  * buffered write path:
  99  * sb_start_write -> i_mutex -> mmap_sem
 100  * sb_start_write -> i_mutex -> transaction start -> page lock ->
 101  *   i_data_sem (rw)
 102  *
 103  * truncate:
 104  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> i_mmap_rwsem (w) -> page lock
 105  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> transaction start ->
 106  *   i_data_sem (rw)
 107  *
 108  * direct IO:
 109  * sb_start_write -> i_mutex -> mmap_sem
 110  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
 111  *
 112  * writepages:
 113  * transaction start -> page lock(s) -> i_data_sem (rw)
 114  */
 115
 116 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 117 static struct file_system_type ext2_fs_type = {
 118         .owner          = THIS_MODULE,
 119         .name           = "ext2",
 120         .mount          = ext4_mount,
 121         .kill_sb        = kill_block_super,
 122         .fs_flags       = FS_REQUIRES_DEV,
 123 };
 124 MODULE_ALIAS_FS("ext2");
 125 MODULE_ALIAS("ext2");
 126 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
 127 #else
 128 #define IS_EXT2_SB(sb) (0)
 129 #endif
 130
 131
 132 static struct file_system_type ext3_fs_type = {
 133         .owner          = THIS_MODULE,
 134         .name           = "ext3",
 135         .mount          = ext4_mount,
 136         .kill_sb        = kill_block_super,
 137         .fs_flags       = FS_REQUIRES_DEV,
 138 };
 139 MODULE_ALIAS_FS("ext3");
 140 MODULE_ALIAS("ext3");
 141 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 142
 143 /*
 144  * This works like sb_bread() except it uses ERR_PTR for error
 145  * returns.  Currently with sb_bread it's impossible to distinguish
 146  * between ENOMEM and EIO situations (since both result in a NULL
 147  * return.
 148  */
 149 struct buffer_head *
 150 ext4_sb_bread(struct super_block *sb, sector_t block, int op_flags)
 151 {
 152         struct buffer_head *bh = sb_getblk(sb, block);
 153
 154         if (bh == NULL)
 155                 return ERR_PTR(-ENOMEM);
 156         if (buffer_uptodate(bh))
 157                 return bh;
 158         ll_rw_block(REQ_OP_READ, REQ_META | op_flags, 1, &bh);
 159         wait_on_buffer(bh);
 160         if (buffer_uptodate(bh))
 161                 return bh;
 162         put_bh(bh);
 163         return ERR_PTR(-EIO);
 164 }
 165
 166 static int ext4_verify_csum_type(struct super_block *sb,
 167                                  struct ext4_super_block *es)
 168 {
 169         if (!ext4_has_feature_metadata_csum(sb))
 170                 return 1;
 171
 172         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 173 }
 174
 175 static __le32 ext4_superblock_csum(struct super_block *sb,
 176                                    struct ext4_super_block *es)
 177 {
 178         struct ext4_sb_info *sbi = EXT4_SB(sb);
 179         int offset = offsetof(struct ext4_super_block, s_checksum);
 180         __u32 csum;
 181
 182         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 183
 184         return cpu_to_le32(csum);
 185 }
 186
 187 static int ext4_superblock_csum_verify(struct super_block *sb,
 188                                        struct ext4_super_block *es)
 189 {
 190         if (!ext4_has_metadata_csum(sb))
 191                 return 1;
 192
 193         return es->s_checksum == ext4_superblock_csum(sb, es);
 194 }
 195
 196 void ext4_superblock_csum_set(struct super_block *sb)
 197 {
 198         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 199
 200         if (!ext4_has_metadata_csum(sb))
 201                 return;
 202
 203         es->s_checksum = ext4_superblock_csum(sb, es);
 204 }
 205
 206 void *ext4_kvmalloc(size_t size, gfp_t flags)
 207 {
 208         void *ret;
 209
 210         ret = kmalloc(size, flags | __GFP_NOWARN);
 211         if (!ret)
 212                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 213         return ret;
 214 }
 215
 216 void *ext4_kvzalloc(size_t size, gfp_t flags)
 217 {
 218         void *ret;
 219
 220         ret = kzalloc(size, flags | __GFP_NOWARN);
 221         if (!ret)
 222                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 223         return ret;
 224 }
 225
 226 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 227                                struct ext4_group_desc *bg)
 228 {
 229         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 230                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 231                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 232 }
 233
 234 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 235                                struct ext4_group_desc *bg)
 236 {
 237         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 238                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 239                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 240 }
 241
 242 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 243                               struct ext4_group_desc *bg)
 244 {
 245         return le32_to_cpu(bg->bg_inode_table_lo) |
 246                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 247                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 248 }
 249
 250 __u32 ext4_free_group_clusters(struct super_block *sb,
 251                                struct ext4_group_desc *bg)
 252 {
 253         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 254                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 255                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 256 }
 257
 258 __u32 ext4_free_inodes_count(struct super_block *sb,
 259                               struct ext4_group_desc *bg)
 260 {
 261         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 262                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 263                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 264 }
 265
 266 __u32 ext4_used_dirs_count(struct super_block *sb,
 267                               struct ext4_group_desc *bg)
 268 {
 269         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 270                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 271                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 272 }
 273
 274 __u32 ext4_itable_unused_count(struct super_block *sb,
 275                               struct ext4_group_desc *bg)
 276 {
 277         return le16_to_cpu(bg->bg_itable_unused_lo) |
 278                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 279                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 280 }
 281
 282 void ext4_block_bitmap_set(struct super_block *sb,
 283                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 284 {
 285         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 286         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 287                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 288 }
 289
 290 void ext4_inode_bitmap_set(struct super_block *sb,
 291                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 292 {
 293         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 294         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 295                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 296 }
 297
 298 void ext4_inode_table_set(struct super_block *sb,
 299                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 300 {
 301         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 302         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 303                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 304 }
 305
 306 void ext4_free_group_clusters_set(struct super_block *sb,
 307                                   struct ext4_group_desc *bg, __u32 count)
 308 {
 309         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 310         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 311                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 312 }
 313
 314 void ext4_free_inodes_set(struct super_block *sb,
 315                           struct ext4_group_desc *bg, __u32 count)
 316 {
 317         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 318         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 319                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 320 }
 321
 322 void ext4_used_dirs_set(struct super_block *sb,
 323                           struct ext4_group_desc *bg, __u32 count)
 324 {
 325         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 326         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 327                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 328 }
 329
 330 void ext4_itable_unused_set(struct super_block *sb,
 331                           struct ext4_group_desc *bg, __u32 count)
 332 {
 333         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 334         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 335                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 336 }
 337
 338 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi)
 339 {
 340         time64_t now = ktime_get_real_seconds();
 341
 342         now = clamp_val(now, 0, (1ull << 40) - 1);
 343
 344         *lo = cpu_to_le32(lower_32_bits(now));
 345         *hi = upper_32_bits(now);
 346 }
 347
 348 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 349 {
 350         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 351 }
 352 #define ext4_update_tstamp(es, tstamp) \
 353         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 354 #define ext4_get_tstamp(es, tstamp) \
 355         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 356
 357 static void __save_error_info(struct super_block *sb, const char *func,
 358                             unsigned int line)
 359 {
 360         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 361
 362         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 363         if (bdev_read_only(sb->s_bdev))
 364                 return;
 365         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 366         ext4_update_tstamp(es, s_last_error_time);
 367         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 368         es->s_last_error_line = cpu_to_le32(line);
 369         if (!es->s_first_error_time) {
 370                 es->s_first_error_time = es->s_last_error_time;
 371                 es->s_first_error_time_hi = es->s_last_error_time_hi;
 372                 strncpy(es->s_first_error_func, func,
 373                         sizeof(es->s_first_error_func));
 374                 es->s_first_error_line = cpu_to_le32(line);
 375                 es->s_first_error_ino = es->s_last_error_ino;
 376                 es->s_first_error_block = es->s_last_error_block;
 377         }
 378         /*
 379          * Start the daily error reporting function if it hasn't been
 380          * started already
 381          */
 382         if (!es->s_error_count)
 383                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 384         le32_add_cpu(&es->s_error_count, 1);
 385 }
 386
 387 static void save_error_info(struct super_block *sb, const char *func,
 388                             unsigned int line)
 389 {
 390         __save_error_info(sb, func, line);
 391         ext4_commit_super(sb, 1);
 392 }
 393
 394 /*
 395  * The del_gendisk() function uninitializes the disk-specific data
 396  * structures, including the bdi structure, without telling anyone
 397  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 398  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 399  * This is a kludge to prevent these oops until we can put in a proper
 400  * hook in del_gendisk() to inform the VFS and file system layers.
 401  */
 402 static int block_device_ejected(struct super_block *sb)
 403 {
 404         struct inode *bd_inode = sb->s_bdev->bd_inode;
 405         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 406
 407         return bdi->dev == NULL;
 408 }
 409
 410 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 411 {
 412         struct super_block              *sb = journal->j_private;
 413         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 414         int                             error = is_journal_aborted(journal);
 415         struct ext4_journal_cb_entry    *jce;
 416
 417         BUG_ON(txn->t_state == T_FINISHED);
 418
 419         ext4_process_freed_data(sb, txn->t_tid);
 420
 421         spin_lock(&sbi->s_md_lock);
 422         while (!list_empty(&txn->t_private_list)) {
 423                 jce = list_entry(txn->t_private_list.next,
 424                                  struct ext4_journal_cb_entry, jce_list);
 425                 list_del_init(&jce->jce_list);
 426                 spin_unlock(&sbi->s_md_lock);
 427                 jce->jce_func(sb, jce, error);
 428                 spin_lock(&sbi->s_md_lock);
 429         }
 430         spin_unlock(&sbi->s_md_lock);
 431 }
 432
 433 static bool system_going_down(void)
 434 {
 435         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 436                 || system_state == SYSTEM_RESTART;
 437 }
 438
 439 /* Deal with the reporting of failure conditions on a filesystem such as
 440  * inconsistencies detected or read IO failures.
 441  *
 442  * On ext2, we can store the error state of the filesystem in the
 443  * superblock.  That is not possible on ext4, because we may have other
 444  * write ordering constraints on the superblock which prevent us from
 445  * writing it out straight away; and given that the journal is about to
 446  * be aborted, we can't rely on the current, or future, transactions to
 447  * write out the superblock safely.
 448  *
 449  * We'll just use the jbd2_journal_abort() error code to record an error in
 450  * the journal instead.  On recovery, the journal will complain about
 451  * that error until we've noted it down and cleared it.
 452  */
 453
 454 static void ext4_handle_error(struct super_block *sb)
 455 {
 456         if (test_opt(sb, WARN_ON_ERROR))
 457                 WARN_ON_ONCE(1);
 458
 459         if (sb_rdonly(sb))
 460                 return;
 461
 462         if (!test_opt(sb, ERRORS_CONT)) {
 463                 journal_t *journal = EXT4_SB(sb)->s_journal;
 464
 465                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 466                 if (journal)
 467                         jbd2_journal_abort(journal, -EIO);
 468         }
 469         /*
 470          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 471          * could panic during 'reboot -f' as the underlying device got already
 472          * disabled.
 473          */
 474         if (test_opt(sb, ERRORS_RO) || system_going_down()) {
 475                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 476                 /*
 477                  * Make sure updated value of ->s_mount_flags will be visible
 478                  * before ->s_flags update
 479                  */
 480                 smp_wmb();
 481                 sb->s_flags |= SB_RDONLY;
 482         } else if (test_opt(sb, ERRORS_PANIC)) {
 483                 if (EXT4_SB(sb)->s_journal &&
 484                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 485                         return;
 486                 panic("EXT4-fs (device %s): panic forced after error\n",
 487                         sb->s_id);
 488         }
 489 }
 490
 491 #define ext4_error_ratelimit(sb)                                        \
 492                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 493                              "EXT4-fs error")
 494
 495 void __ext4_error(struct super_block *sb, const char *function,
 496                   unsigned int line, const char *fmt, ...)
 497 {
 498         struct va_format vaf;
 499         va_list args;
 500
 501         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 502                 return;
 503
 504         trace_ext4_error(sb, function, line);
 505         if (ext4_error_ratelimit(sb)) {
 506                 va_start(args, fmt);
 507                 vaf.fmt = fmt;
 508                 vaf.va = &args;
 509                 printk(KERN_CRIT
 510                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 511                        sb->s_id, function, line, current->comm, &vaf);
 512                 va_end(args);
 513         }
 514         save_error_info(sb, function, line);
 515         ext4_handle_error(sb);
 516 }
 517
 518 void __ext4_error_inode(struct inode *inode, const char *function,
 519                         unsigned int line, ext4_fsblk_t block,
 520                         const char *fmt, ...)
 521 {
 522         va_list args;
 523         struct va_format vaf;
 524         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 525
 526         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 527                 return;
 528
 529         trace_ext4_error(inode->i_sb, function, line);
 530         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 531         es->s_last_error_block = cpu_to_le64(block);
 532         if (ext4_error_ratelimit(inode->i_sb)) {
 533                 va_start(args, fmt);
 534                 vaf.fmt = fmt;
 535                 vaf.va = &args;
 536                 if (block)
 537                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 538                                "inode #%lu: block %llu: comm %s: %pV\n",
 539                                inode->i_sb->s_id, function, line, inode->i_ino,
 540                                block, current->comm, &vaf);
 541                 else
 542                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 543                                "inode #%lu: comm %s: %pV\n",
 544                                inode->i_sb->s_id, function, line, inode->i_ino,
 545                                current->comm, &vaf);
 546                 va_end(args);
 547         }
 548         save_error_info(inode->i_sb, function, line);
 549         ext4_handle_error(inode->i_sb);
 550 }
 551
 552 void __ext4_error_file(struct file *file, const char *function,
 553                        unsigned int line, ext4_fsblk_t block,
 554                        const char *fmt, ...)
 555 {
 556         va_list args;
 557         struct va_format vaf;
 558         struct ext4_super_block *es;
 559         struct inode *inode = file_inode(file);
 560         char pathname[80], *path;
 561
 562         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 563                 return;
 564
 565         trace_ext4_error(inode->i_sb, function, line);
 566         es = EXT4_SB(inode->i_sb)->s_es;
 567         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 568         if (ext4_error_ratelimit(inode->i_sb)) {
 569                 path = file_path(file, pathname, sizeof(pathname));
 570                 if (IS_ERR(path))
 571                         path = "(unknown)";
 572                 va_start(args, fmt);
 573                 vaf.fmt = fmt;
 574                 vaf.va = &args;
 575                 if (block)
 576                         printk(KERN_CRIT
 577                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 578                                "block %llu: comm %s: path %s: %pV\n",
 579                                inode->i_sb->s_id, function, line, inode->i_ino,
 580                                block, current->comm, path, &vaf);
 581                 else
 582                         printk(KERN_CRIT
 583                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 584                                "comm %s: path %s: %pV\n",
 585                                inode->i_sb->s_id, function, line, inode->i_ino,
 586                                current->comm, path, &vaf);
 587                 va_end(args);
 588         }
 589         save_error_info(inode->i_sb, function, line);
 590         ext4_handle_error(inode->i_sb);
 591 }
 592
 593 const char *ext4_decode_error(struct super_block *sb, int errno,
 594                               char nbuf[16])
 595 {
 596         char *errstr = NULL;
 597
 598         switch (errno) {
 599         case -EFSCORRUPTED:
 600                 errstr = "Corrupt filesystem";
 601                 break;
 602         case -EFSBADCRC:
 603                 errstr = "Filesystem failed CRC";
 604                 break;
 605         case -EIO:
 606                 errstr = "IO failure";
 607                 break;
 608         case -ENOMEM:
 609                 errstr = "Out of memory";
 610                 break;
 611         case -EROFS:
 612                 if (!sb || (EXT4_SB(sb)->s_journal &&
 613                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 614                         errstr = "Journal has aborted";
 615                 else
 616                         errstr = "Readonly filesystem";
 617                 break;
 618         default:
 619                 /* If the caller passed in an extra buffer for unknown
 620                  * errors, textualise them now.  Else we just return
 621                  * NULL. */
 622                 if (nbuf) {
 623                         /* Check for truncated error codes... */
 624                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 625                                 errstr = nbuf;
 626                 }
 627                 break;
 628         }
 629
 630         return errstr;
 631 }
 632
 633 /* __ext4_std_error decodes expected errors from journaling functions
 634  * automatically and invokes the appropriate error response.  */
 635
 636 void __ext4_std_error(struct super_block *sb, const char *function,
 637                       unsigned int line, int errno)
 638 {
 639         char nbuf[16];
 640         const char *errstr;
 641
 642         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 643                 return;
 644
 645         /* Special case: if the error is EROFS, and we're not already
 646          * inside a transaction, then there's really no point in logging
 647          * an error. */
 648         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 649                 return;
 650
 651         if (ext4_error_ratelimit(sb)) {
 652                 errstr = ext4_decode_error(sb, errno, nbuf);
 653                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 654                        sb->s_id, function, line, errstr);
 655         }
 656
 657         save_error_info(sb, function, line);
 658         ext4_handle_error(sb);
 659 }
 660
 661 /*
 662  * ext4_abort is a much stronger failure handler than ext4_error.  The
 663  * abort function may be used to deal with unrecoverable failures such
 664  * as journal IO errors or ENOMEM at a critical moment in log management.
 665  *
 666  * We unconditionally force the filesystem into an ABORT|READONLY state,
 667  * unless the error response on the fs has been set to panic in which
 668  * case we take the easy way out and panic immediately.
 669  */
 670
 671 void __ext4_abort(struct super_block *sb, const char *function,
 672                 unsigned int line, const char *fmt, ...)
 673 {
 674         struct va_format vaf;
 675         va_list args;
 676
 677         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 678                 return;
 679
 680         save_error_info(sb, function, line);
 681         va_start(args, fmt);
 682         vaf.fmt = fmt;
 683         vaf.va = &args;
 684         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 685                sb->s_id, function, line, &vaf);
 686         va_end(args);
 687
 688         if (sb_rdonly(sb) == 0) {
 689                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 690                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 691                 /*
 692                  * Make sure updated value of ->s_mount_flags will be visible
 693                  * before ->s_flags update
 694                  */
 695                 smp_wmb();
 696                 sb->s_flags |= SB_RDONLY;
 697                 if (EXT4_SB(sb)->s_journal)
 698                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 699                 save_error_info(sb, function, line);
 700         }
 701         if (test_opt(sb, ERRORS_PANIC)) {
 702                 if (EXT4_SB(sb)->s_journal &&
 703                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 704                         return;
 705                 panic("EXT4-fs panic from previous error\n");
 706         }
 707 }
 708
 709 void __ext4_msg(struct super_block *sb,
 710                 const char *prefix, const char *fmt, ...)
 711 {
 712         struct va_format vaf;
 713         va_list args;
 714
 715         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 716                 return;
 717
 718         va_start(args, fmt);
 719         vaf.fmt = fmt;
 720         vaf.va = &args;
 721         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 722         va_end(args);
 723 }
 724
 725 #define ext4_warning_ratelimit(sb)                                      \
 726                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 727                              "EXT4-fs warning")
 728
 729 void __ext4_warning(struct super_block *sb, const char *function,
 730                     unsigned int line, const char *fmt, ...)
 731 {
 732         struct va_format vaf;
 733         va_list args;
 734
 735         if (!ext4_warning_ratelimit(sb))
 736                 return;
 737
 738         va_start(args, fmt);
 739         vaf.fmt = fmt;
 740         vaf.va = &args;
 741         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 742                sb->s_id, function, line, &vaf);
 743         va_end(args);
 744 }
 745
 746 void __ext4_warning_inode(const struct inode *inode, const char *function,
 747                           unsigned int line, const char *fmt, ...)
 748 {
 749         struct va_format vaf;
 750         va_list args;
 751
 752         if (!ext4_warning_ratelimit(inode->i_sb))
 753                 return;
 754
 755         va_start(args, fmt);
 756         vaf.fmt = fmt;
 757         vaf.va = &args;
 758         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 759                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 760                function, line, inode->i_ino, current->comm, &vaf);
 761         va_end(args);
 762 }
 763
 764 void __ext4_grp_locked_error(const char *function, unsigned int line,
 765                              struct super_block *sb, ext4_group_t grp,
 766                              unsigned long ino, ext4_fsblk_t block,
 767                              const char *fmt, ...)
 768 __releases(bitlock)
 769 __acquires(bitlock)
 770 {
 771         struct va_format vaf;
 772         va_list args;
 773         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 774
 775         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 776                 return;
 777
 778         trace_ext4_error(sb, function, line);
 779         es->s_last_error_ino = cpu_to_le32(ino);
 780         es->s_last_error_block = cpu_to_le64(block);
 781         __save_error_info(sb, function, line);
 782
 783         if (ext4_error_ratelimit(sb)) {
 784                 va_start(args, fmt);
 785                 vaf.fmt = fmt;
 786                 vaf.va = &args;
 787                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 788                        sb->s_id, function, line, grp);
 789                 if (ino)
 790                         printk(KERN_CONT "inode %lu: ", ino);
 791                 if (block)
 792                         printk(KERN_CONT "block %llu:",
 793                                (unsigned long long) block);
 794                 printk(KERN_CONT "%pV\n", &vaf);
 795                 va_end(args);
 796         }
 797
 798         if (test_opt(sb, WARN_ON_ERROR))
 799                 WARN_ON_ONCE(1);
 800
 801         if (test_opt(sb, ERRORS_CONT)) {
 802                 ext4_commit_super(sb, 0);
 803                 return;
 804         }
 805
 806         ext4_unlock_group(sb, grp);
 807         ext4_commit_super(sb, 1);
 808         ext4_handle_error(sb);
 809         /*
 810          * We only get here in the ERRORS_RO case; relocking the group
 811          * may be dangerous, but nothing bad will happen since the
 812          * filesystem will have already been marked read/only and the
 813          * journal has been aborted.  We return 1 as a hint to callers
 814          * who might what to use the return value from
 815          * ext4_grp_locked_error() to distinguish between the
 816          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 817          * aggressively from the ext4 function in question, with a
 818          * more appropriate error code.
 819          */
 820         ext4_lock_group(sb, grp);
 821         return;
 822 }
 823
 824 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
 825                                      ext4_group_t group,
 826                                      unsigned int flags)
 827 {
 828         struct ext4_sb_info *sbi = EXT4_SB(sb);
 829         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
 830         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
 831         int ret;
 832
 833         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
 834                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
 835                                             &grp->bb_state);
 836                 if (!ret)
 837                         percpu_counter_sub(&sbi->s_freeclusters_counter,
 838                                            grp->bb_free);
 839         }
 840
 841         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
 842                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
 843                                             &grp->bb_state);
 844                 if (!ret && gdp) {
 845                         int count;
 846
 847                         count = ext4_free_inodes_count(sb, gdp);
 848                         percpu_counter_sub(&sbi->s_freeinodes_counter,
 849                                            count);
 850                 }
 851         }
 852 }
 853
 854 void ext4_update_dynamic_rev(struct super_block *sb)
 855 {
 856         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 857
 858         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 859                 return;
 860
 861         ext4_warning(sb,
 862                      "updating to rev %d because of new feature flag, "
 863                      "running e2fsck is recommended",
 864                      EXT4_DYNAMIC_REV);
 865
 866         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 867         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 868         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 869         /* leave es->s_feature_*compat flags alone */
 870         /* es->s_uuid will be set by e2fsck if empty */
 871
 872         /*
 873          * The rest of the superblock fields should be zero, and if not it
 874          * means they are likely already in use, so leave them alone.  We
 875          * can leave it up to e2fsck to clean up any inconsistencies there.
 876          */
 877 }
 878
 879 /*
 880  * Open the external journal device
 881  */
 882 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 883 {
 884         struct block_device *bdev;
 885         char b[BDEVNAME_SIZE];
 886
 887         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 888         if (IS_ERR(bdev))
 889                 goto fail;
 890         return bdev;
 891
 892 fail:
 893         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 894                         __bdevname(dev, b), PTR_ERR(bdev));
 895         return NULL;
 896 }
 897
 898 /*
 899  * Release the journal device
 900  */
 901 static void ext4_blkdev_put(struct block_device *bdev)
 902 {
 903         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 904 }
 905
 906 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 907 {
 908         struct block_device *bdev;
 909         bdev = sbi->journal_bdev;
 910         if (bdev) {
 911                 ext4_blkdev_put(bdev);
 912                 sbi->journal_bdev = NULL;
 913         }
 914 }
 915
 916 static inline struct inode *orphan_list_entry(struct list_head *l)
 917 {
 918         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 919 }
 920
 921 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 922 {
 923         struct list_head *l;
 924
 925         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 926                  le32_to_cpu(sbi->s_es->s_last_orphan));
 927
 928         printk(KERN_ERR "sb_info orphan list:\n");
 929         list_for_each(l, &sbi->s_orphan) {
 930                 struct inode *inode = orphan_list_entry(l);
 931                 printk(KERN_ERR "  "
 932                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 933                        inode->i_sb->s_id, inode->i_ino, inode,
 934                        inode->i_mode, inode->i_nlink,
 935                        NEXT_ORPHAN(inode));
 936         }
 937 }
 938
 939 #ifdef CONFIG_QUOTA
 940 static int ext4_quota_off(struct super_block *sb, int type);
 941
 942 static inline void ext4_quota_off_umount(struct super_block *sb)
 943 {
 944         int type;
 945
 946         /* Use our quota_off function to clear inode flags etc. */
 947         for (type = 0; type < EXT4_MAXQUOTAS; type++)
 948                 ext4_quota_off(sb, type);
 949 }
 950
 951 /*
 952  * This is a helper function which is used in the mount/remount
 953  * codepaths (which holds s_umount) to fetch the quota file name.
 954  */
 955 static inline char *get_qf_name(struct super_block *sb,
 956                                 struct ext4_sb_info *sbi,
 957                                 int type)
 958 {
 959         return rcu_dereference_protected(sbi->s_qf_names[type],
 960                                          lockdep_is_held(&sb->s_umount));
 961 }
 962 #else
 963 static inline void ext4_quota_off_umount(struct super_block *sb)
 964 {
 965 }
 966 #endif
 967
 968 static void ext4_put_super(struct super_block *sb)
 969 {
 970         struct ext4_sb_info *sbi = EXT4_SB(sb);
 971         struct ext4_super_block *es = sbi->s_es;
 972         int aborted = 0;
 973         int i, err;
 974
 975         ext4_unregister_li_request(sb);
 976         ext4_quota_off_umount(sb);
 977
 978         destroy_workqueue(sbi->rsv_conversion_wq);
 979
 980         if (sbi->s_journal) {
 981                 aborted = is_journal_aborted(sbi->s_journal);
 982                 err = jbd2_journal_destroy(sbi->s_journal);
 983                 sbi->s_journal = NULL;
 984                 if ((err < 0) && !aborted)
 985                         ext4_abort(sb, "Couldn't clean up the journal");
 986         }
 987
 988         ext4_unregister_sysfs(sb);
 989         ext4_es_unregister_shrinker(sbi);
 990         del_timer_sync(&sbi->s_err_report);
 991         ext4_release_system_zone(sb);
 992         ext4_mb_release(sb);
 993         ext4_ext_release(sb);
 994
 995         if (!sb_rdonly(sb) && !aborted) {
 996                 ext4_clear_feature_journal_needs_recovery(sb);
 997                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 998         }
 999         if (!sb_rdonly(sb))
1000                 ext4_commit_super(sb, 1);
1001
1002         for (i = 0; i < sbi->s_gdb_count; i++)
1003                 brelse(sbi->s_group_desc[i]);
1004         kvfree(sbi->s_group_desc);
1005         kvfree(sbi->s_flex_groups);
1006         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1007         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1008         percpu_counter_destroy(&sbi->s_dirs_counter);
1009         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1010         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
1011 #ifdef CONFIG_QUOTA
1012         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1013                 kfree(get_qf_name(sb, sbi, i));
1014 #endif
1015
1016         /* Debugging code just in case the in-memory inode orphan list
1017          * isn't empty.  The on-disk one can be non-empty if we've
1018          * detected an error and taken the fs readonly, but the
1019          * in-memory list had better be clean by this point. */
1020         if (!list_empty(&sbi->s_orphan))
1021                 dump_orphan_list(sb, sbi);
1022         J_ASSERT(list_empty(&sbi->s_orphan));
1023
1024         sync_blockdev(sb->s_bdev);
1025         invalidate_bdev(sb->s_bdev);
1026         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
1027                 /*
1028                  * Invalidate the journal device's buffers.  We don't want them
1029                  * floating about in memory - the physical journal device may
1030                  * hotswapped, and it breaks the `ro-after' testing code.
1031                  */
1032                 sync_blockdev(sbi->journal_bdev);
1033                 invalidate_bdev(sbi->journal_bdev);
1034                 ext4_blkdev_remove(sbi);
1035         }
1036
1037         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1038         sbi->s_ea_inode_cache = NULL;
1039
1040         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1041         sbi->s_ea_block_cache = NULL;
1042
1043         if (sbi->s_mmp_tsk)
1044                 kthread_stop(sbi->s_mmp_tsk);
1045         brelse(sbi->s_sbh);
1046         sb->s_fs_info = NULL;
1047         /*
1048          * Now that we are completely done shutting down the
1049          * superblock, we need to actually destroy the kobject.
1050          */
1051         kobject_put(&sbi->s_kobj);
1052         wait_for_completion(&sbi->s_kobj_unregister);
1053         if (sbi->s_chksum_driver)
1054                 crypto_free_shash(sbi->s_chksum_driver);
1055         kfree(sbi->s_blockgroup_lock);
1056         fs_put_dax(sbi->s_daxdev);
1057         kfree(sbi);
1058 }
1059
1060 static struct kmem_cache *ext4_inode_cachep;
1061
1062 /*
1063  * Called inside transaction, so use GFP_NOFS
1064  */
1065 static struct inode *ext4_alloc_inode(struct super_block *sb)
1066 {
1067         struct ext4_inode_info *ei;
1068
1069         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1070         if (!ei)
1071                 return NULL;
1072
1073         inode_set_iversion(&ei->vfs_inode, 1);
1074         spin_lock_init(&ei->i_raw_lock);
1075         INIT_LIST_HEAD(&ei->i_prealloc_list);
1076         spin_lock_init(&ei->i_prealloc_lock);
1077         ext4_es_init_tree(&ei->i_es_tree);
1078         rwlock_init(&ei->i_es_lock);
1079         INIT_LIST_HEAD(&ei->i_es_list);
1080         ei->i_es_all_nr = 0;
1081         ei->i_es_shk_nr = 0;
1082         ei->i_es_shrink_lblk = 0;
1083         ei->i_reserved_data_blocks = 0;
1084         ei->i_da_metadata_calc_len = 0;
1085         ei->i_da_metadata_calc_last_lblock = 0;
1086         spin_lock_init(&(ei->i_block_reservation_lock));
1087         ext4_init_pending_tree(&ei->i_pending_tree);
1088 #ifdef CONFIG_QUOTA
1089         ei->i_reserved_quota = 0;
1090         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1091 #endif
1092         ei->jinode = NULL;
1093         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1094         spin_lock_init(&ei->i_completed_io_lock);
1095         ei->i_sync_tid = 0;
1096         ei->i_datasync_tid = 0;
1097         atomic_set(&ei->i_unwritten, 0);
1098         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1099         return &ei->vfs_inode;
1100 }
1101
1102 static int ext4_drop_inode(struct inode *inode)
1103 {
1104         int drop = generic_drop_inode(inode);
1105
1106         trace_ext4_drop_inode(inode, drop);
1107         return drop;
1108 }
1109
1110 static void ext4_i_callback(struct rcu_head *head)
1111 {
1112         struct inode *inode = container_of(head, struct inode, i_rcu);
1113         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1114 }
1115
1116 static void ext4_destroy_inode(struct inode *inode)
1117 {
1118         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1119                 ext4_msg(inode->i_sb, KERN_ERR,
1120                          "Inode %lu (%p): orphan list check failed!",
1121                          inode->i_ino, EXT4_I(inode));
1122                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1123                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1124                                 true);
1125                 dump_stack();
1126         }
1127         call_rcu(&inode->i_rcu, ext4_i_callback);
1128 }
1129
1130 static void init_once(void *foo)
1131 {
1132         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1133
1134         INIT_LIST_HEAD(&ei->i_orphan);
1135         init_rwsem(&ei->xattr_sem);
1136         init_rwsem(&ei->i_data_sem);
1137         init_rwsem(&ei->i_mmap_sem);
1138         inode_init_once(&ei->vfs_inode);
1139 }
1140
1141 static int __init init_inodecache(void)
1142 {
1143         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1144                                 sizeof(struct ext4_inode_info), 0,
1145                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1146                                         SLAB_ACCOUNT),
1147                                 offsetof(struct ext4_inode_info, i_data),
1148                                 sizeof_field(struct ext4_inode_info, i_data),
1149                                 init_once);
1150         if (ext4_inode_cachep == NULL)
1151                 return -ENOMEM;
1152         return 0;
1153 }
1154
1155 static void destroy_inodecache(void)
1156 {
1157         /*
1158          * Make sure all delayed rcu free inodes are flushed before we
1159          * destroy cache.
1160          */
1161         rcu_barrier();
1162         kmem_cache_destroy(ext4_inode_cachep);
1163 }
1164
1165 void ext4_clear_inode(struct inode *inode)
1166 {
1167         invalidate_inode_buffers(inode);
1168         clear_inode(inode);
1169         dquot_drop(inode);
1170         ext4_discard_preallocations(inode);
1171         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1172         if (EXT4_I(inode)->jinode) {
1173                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1174                                                EXT4_I(inode)->jinode);
1175                 jbd2_free_inode(EXT4_I(inode)->jinode);
1176                 EXT4_I(inode)->jinode = NULL;
1177         }
1178         fscrypt_put_encryption_info(inode);
1179 }
1180
1181 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1182                                         u64 ino, u32 generation)
1183 {
1184         struct inode *inode;
1185
1186         /*
1187          * Currently we don't know the generation for parent directory, so
1188          * a generation of 0 means "accept any"
1189          */
1190         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1191         if (IS_ERR(inode))
1192                 return ERR_CAST(inode);
1193         if (generation && inode->i_generation != generation) {
1194                 iput(inode);
1195                 return ERR_PTR(-ESTALE);
1196         }
1197
1198         return inode;
1199 }
1200
1201 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1202                                         int fh_len, int fh_type)
1203 {
1204         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1205                                     ext4_nfs_get_inode);
1206 }
1207
1208 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1209                                         int fh_len, int fh_type)
1210 {
1211         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1212                                     ext4_nfs_get_inode);
1213 }
1214
1215 static int ext4_nfs_commit_metadata(struct inode *inode)
1216 {
1217         struct writeback_control wbc = {
1218                 .sync_mode = WB_SYNC_ALL
1219         };
1220
1221         trace_ext4_nfs_commit_metadata(inode);
1222         return ext4_write_inode(inode, &wbc);
1223 }
1224
1225 /*
1226  * Try to release metadata pages (indirect blocks, directories) which are
1227  * mapped via the block device.  Since these pages could have journal heads
1228  * which would prevent try_to_free_buffers() from freeing them, we must use
1229  * jbd2 layer's try_to_free_buffers() function to release them.
1230  */
1231 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1232                                  gfp_t wait)
1233 {
1234         journal_t *journal = EXT4_SB(sb)->s_journal;
1235
1236         WARN_ON(PageChecked(page));
1237         if (!page_has_buffers(page))
1238                 return 0;
1239         if (journal)
1240                 return jbd2_journal_try_to_free_buffers(journal, page,
1241                                                 wait & ~__GFP_DIRECT_RECLAIM);
1242         return try_to_free_buffers(page);
1243 }
1244
1245 #ifdef CONFIG_FS_ENCRYPTION
1246 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1247 {
1248         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1249                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1250 }
1251
1252 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1253                                                         void *fs_data)
1254 {
1255         handle_t *handle = fs_data;
1256         int res, res2, credits, retries = 0;
1257
1258         /*
1259          * Encrypting the root directory is not allowed because e2fsck expects
1260          * lost+found to exist and be unencrypted, and encrypting the root
1261          * directory would imply encrypting the lost+found directory as well as
1262          * the filename "lost+found" itself.
1263          */
1264         if (inode->i_ino == EXT4_ROOT_INO)
1265                 return -EPERM;
1266
1267         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1268                 return -EINVAL;
1269
1270         res = ext4_convert_inline_data(inode);
1271         if (res)
1272                 return res;
1273
1274         /*
1275          * If a journal handle was specified, then the encryption context is
1276          * being set on a new inode via inheritance and is part of a larger
1277          * transaction to create the inode.  Otherwise the encryption context is
1278          * being set on an existing inode in its own transaction.  Only in the
1279          * latter case should the "retry on ENOSPC" logic be used.
1280          */
1281
1282         if (handle) {
1283                 res = ext4_xattr_set_handle(handle, inode,
1284                                             EXT4_XATTR_INDEX_ENCRYPTION,
1285                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1286                                             ctx, len, 0);
1287                 if (!res) {
1288                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1289                         ext4_clear_inode_state(inode,
1290                                         EXT4_STATE_MAY_INLINE_DATA);
1291                         /*
1292                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1293                          * S_DAX may be disabled
1294                          */
1295                         ext4_set_inode_flags(inode);
1296                 }
1297                 return res;
1298         }
1299
1300         res = dquot_initialize(inode);
1301         if (res)
1302                 return res;
1303 retry:
1304         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1305                                      &credits);
1306         if (res)
1307                 return res;
1308
1309         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1310         if (IS_ERR(handle))
1311                 return PTR_ERR(handle);
1312
1313         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1314                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1315                                     ctx, len, 0);
1316         if (!res) {
1317                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1318                 /*
1319                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1320                  * S_DAX may be disabled
1321                  */
1322                 ext4_set_inode_flags(inode);
1323                 res = ext4_mark_inode_dirty(handle, inode);
1324                 if (res)
1325                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1326         }
1327         res2 = ext4_journal_stop(handle);
1328
1329         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1330                 goto retry;
1331         if (!res)
1332                 res = res2;
1333         return res;
1334 }
1335
1336 static bool ext4_dummy_context(struct inode *inode)
1337 {
1338         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1339 }
1340
1341 static const struct fscrypt_operations ext4_cryptops = {
1342         .key_prefix             = "ext4:",
1343         .get_context            = ext4_get_context,
1344         .set_context            = ext4_set_context,
1345         .dummy_context          = ext4_dummy_context,
1346         .empty_dir              = ext4_empty_dir,
1347         .max_namelen            = EXT4_NAME_LEN,
1348 };
1349 #endif
1350
1351 #ifdef CONFIG_QUOTA
1352 static const char * const quotatypes[] = INITQFNAMES;
1353 #define QTYPE2NAME(t) (quotatypes[t])
1354
1355 static int ext4_write_dquot(struct dquot *dquot);
1356 static int ext4_acquire_dquot(struct dquot *dquot);
1357 static int ext4_release_dquot(struct dquot *dquot);
1358 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1359 static int ext4_write_info(struct super_block *sb, int type);
1360 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1361                          const struct path *path);
1362 static int ext4_quota_on_mount(struct super_block *sb, int type);
1363 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1364                                size_t len, loff_t off);
1365 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1366                                 const char *data, size_t len, loff_t off);
1367 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1368                              unsigned int flags);
1369 static int ext4_enable_quotas(struct super_block *sb);
1370 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid);
1371
1372 static struct dquot **ext4_get_dquots(struct inode *inode)
1373 {
1374         return EXT4_I(inode)->i_dquot;
1375 }
1376
1377 static const struct dquot_operations ext4_quota_operations = {
1378         .get_reserved_space     = ext4_get_reserved_space,
1379         .write_dquot            = ext4_write_dquot,
1380         .acquire_dquot          = ext4_acquire_dquot,
1381         .release_dquot          = ext4_release_dquot,
1382         .mark_dirty             = ext4_mark_dquot_dirty,
1383         .write_info             = ext4_write_info,
1384         .alloc_dquot            = dquot_alloc,
1385         .destroy_dquot          = dquot_destroy,
1386         .get_projid             = ext4_get_projid,
1387         .get_inode_usage        = ext4_get_inode_usage,
1388         .get_next_id            = ext4_get_next_id,
1389 };
1390
1391 static const struct quotactl_ops ext4_qctl_operations = {
1392         .quota_on       = ext4_quota_on,
1393         .quota_off      = ext4_quota_off,
1394         .quota_sync     = dquot_quota_sync,
1395         .get_state      = dquot_get_state,
1396         .set_info       = dquot_set_dqinfo,
1397         .get_dqblk      = dquot_get_dqblk,
1398         .set_dqblk      = dquot_set_dqblk,
1399         .get_nextdqblk  = dquot_get_next_dqblk,
1400 };
1401 #endif
1402
1403 static const struct super_operations ext4_sops = {
1404         .alloc_inode    = ext4_alloc_inode,
1405         .destroy_inode  = ext4_destroy_inode,
1406         .write_inode    = ext4_write_inode,
1407         .dirty_inode    = ext4_dirty_inode,
1408         .drop_inode     = ext4_drop_inode,
1409         .evict_inode    = ext4_evict_inode,
1410         .put_super      = ext4_put_super,
1411         .sync_fs        = ext4_sync_fs,
1412         .freeze_fs      = ext4_freeze,
1413         .unfreeze_fs    = ext4_unfreeze,
1414         .statfs         = ext4_statfs,
1415         .remount_fs     = ext4_remount,
1416         .show_options   = ext4_show_options,
1417 #ifdef CONFIG_QUOTA
1418         .quota_read     = ext4_quota_read,
1419         .quota_write    = ext4_quota_write,
1420         .get_dquots     = ext4_get_dquots,
1421 #endif
1422         .bdev_try_to_free_page = bdev_try_to_free_page,
1423 };
1424
1425 static const struct export_operations ext4_export_ops = {
1426         .fh_to_dentry = ext4_fh_to_dentry,
1427         .fh_to_parent = ext4_fh_to_parent,
1428         .get_parent = ext4_get_parent,
1429         .commit_metadata = ext4_nfs_commit_metadata,
1430 };
1431
1432 enum {
1433         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1434         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1435         Opt_nouid32, Opt_debug, Opt_removed,
1436         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1437         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1438         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1439         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1440         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1441         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1442         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1443         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1444         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1445         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1446         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1447         Opt_nowarn_on_error, Opt_mblk_io_submit,
1448         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1449         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1450         Opt_inode_readahead_blks, Opt_journal_ioprio,
1451         Opt_dioread_nolock, Opt_dioread_lock,
1452         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1453         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1454 };
1455
1456 static const match_table_t tokens = {
1457         {Opt_bsd_df, "bsddf"},
1458         {Opt_minix_df, "minixdf"},
1459         {Opt_grpid, "grpid"},
1460         {Opt_grpid, "bsdgroups"},
1461         {Opt_nogrpid, "nogrpid"},
1462         {Opt_nogrpid, "sysvgroups"},
1463         {Opt_resgid, "resgid=%u"},
1464         {Opt_resuid, "resuid=%u"},
1465         {Opt_sb, "sb=%u"},
1466         {Opt_err_cont, "errors=continue"},
1467         {Opt_err_panic, "errors=panic"},
1468         {Opt_err_ro, "errors=remount-ro"},
1469         {Opt_nouid32, "nouid32"},
1470         {Opt_debug, "debug"},
1471         {Opt_removed, "oldalloc"},
1472         {Opt_removed, "orlov"},
1473         {Opt_user_xattr, "user_xattr"},
1474         {Opt_nouser_xattr, "nouser_xattr"},
1475         {Opt_acl, "acl"},
1476         {Opt_noacl, "noacl"},
1477         {Opt_noload, "norecovery"},
1478         {Opt_noload, "noload"},
1479         {Opt_removed, "nobh"},
1480         {Opt_removed, "bh"},
1481         {Opt_commit, "commit=%u"},
1482         {Opt_min_batch_time, "min_batch_time=%u"},
1483         {Opt_max_batch_time, "max_batch_time=%u"},
1484         {Opt_journal_dev, "journal_dev=%u"},
1485         {Opt_journal_path, "journal_path=%s"},
1486         {Opt_journal_checksum, "journal_checksum"},
1487         {Opt_nojournal_checksum, "nojournal_checksum"},
1488         {Opt_journal_async_commit, "journal_async_commit"},
1489         {Opt_abort, "abort"},
1490         {Opt_data_journal, "data=journal"},
1491         {Opt_data_ordered, "data=ordered"},
1492         {Opt_data_writeback, "data=writeback"},
1493         {Opt_data_err_abort, "data_err=abort"},
1494         {Opt_data_err_ignore, "data_err=ignore"},
1495         {Opt_offusrjquota, "usrjquota="},
1496         {Opt_usrjquota, "usrjquota=%s"},
1497         {Opt_offgrpjquota, "grpjquota="},
1498         {Opt_grpjquota, "grpjquota=%s"},
1499         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1500         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1501         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1502         {Opt_grpquota, "grpquota"},
1503         {Opt_noquota, "noquota"},
1504         {Opt_quota, "quota"},
1505         {Opt_usrquota, "usrquota"},
1506         {Opt_prjquota, "prjquota"},
1507         {Opt_barrier, "barrier=%u"},
1508         {Opt_barrier, "barrier"},
1509         {Opt_nobarrier, "nobarrier"},
1510         {Opt_i_version, "i_version"},
1511         {Opt_dax, "dax"},
1512         {Opt_stripe, "stripe=%u"},
1513         {Opt_delalloc, "delalloc"},
1514         {Opt_warn_on_error, "warn_on_error"},
1515         {Opt_nowarn_on_error, "nowarn_on_error"},
1516         {Opt_lazytime, "lazytime"},
1517         {Opt_nolazytime, "nolazytime"},
1518         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1519         {Opt_nodelalloc, "nodelalloc"},
1520         {Opt_removed, "mblk_io_submit"},
1521         {Opt_removed, "nomblk_io_submit"},
1522         {Opt_block_validity, "block_validity"},
1523         {Opt_noblock_validity, "noblock_validity"},
1524         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1525         {Opt_journal_ioprio, "journal_ioprio=%u"},
1526         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1527         {Opt_auto_da_alloc, "auto_da_alloc"},
1528         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1529         {Opt_dioread_nolock, "dioread_nolock"},
1530         {Opt_dioread_lock, "dioread_lock"},
1531         {Opt_discard, "discard"},
1532         {Opt_nodiscard, "nodiscard"},
1533         {Opt_init_itable, "init_itable=%u"},
1534         {Opt_init_itable, "init_itable"},
1535         {Opt_noinit_itable, "noinit_itable"},
1536         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1537         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1538         {Opt_nombcache, "nombcache"},
1539         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1540         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1541         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1542         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1543         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1544         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1545         {Opt_err, NULL},
1546 };
1547
1548 static ext4_fsblk_t get_sb_block(void **data)
1549 {
1550         ext4_fsblk_t    sb_block;
1551         char            *options = (char *) *data;
1552
1553         if (!options || strncmp(options, "sb=", 3) != 0)
1554                 return 1;       /* Default location */
1555
1556         options += 3;
1557         /* TODO: use simple_strtoll with >32bit ext4 */
1558         sb_block = simple_strtoul(options, &options, 0);
1559         if (*options && *options != ',') {
1560                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1561                        (char *) *data);
1562                 return 1;
1563         }
1564         if (*options == ',')
1565                 options++;
1566         *data = (void *) options;
1567
1568         return sb_block;
1569 }
1570
1571 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1572 static const char deprecated_msg[] =
1573         "Mount option \"%s\" will be removed by %s\n"
1574         "Contact [email protected] if you think we should keep it.\n";
1575
1576 #ifdef CONFIG_QUOTA
1577 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1578 {
1579         struct ext4_sb_info *sbi = EXT4_SB(sb);
1580         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1581         int ret = -1;
1582
1583         if (sb_any_quota_loaded(sb) && !old_qname) {
1584                 ext4_msg(sb, KERN_ERR,
1585                         "Cannot change journaled "
1586                         "quota options when quota turned on");
1587                 return -1;
1588         }
1589         if (ext4_has_feature_quota(sb)) {
1590                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1591                          "ignored when QUOTA feature is enabled");
1592                 return 1;
1593         }
1594         qname = match_strdup(args);
1595         if (!qname) {
1596                 ext4_msg(sb, KERN_ERR,
1597                         "Not enough memory for storing quotafile name");
1598                 return -1;
1599         }
1600         if (old_qname) {
1601                 if (strcmp(old_qname, qname) == 0)
1602                         ret = 1;
1603                 else
1604                         ext4_msg(sb, KERN_ERR,
1605                                  "%s quota file already specified",
1606                                  QTYPE2NAME(qtype));
1607                 goto errout;
1608         }
1609         if (strchr(qname, '/')) {
1610                 ext4_msg(sb, KERN_ERR,
1611                         "quotafile must be on filesystem root");
1612                 goto errout;
1613         }
1614         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1615         set_opt(sb, QUOTA);
1616         return 1;
1617 errout:
1618         kfree(qname);
1619         return ret;
1620 }
1621
1622 static int clear_qf_name(struct super_block *sb, int qtype)
1623 {
1624
1625         struct ext4_sb_info *sbi = EXT4_SB(sb);
1626         char *old_qname = get_qf_name(sb, sbi, qtype);
1627
1628         if (sb_any_quota_loaded(sb) && old_qname) {
1629                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1630                         " when quota turned on");
1631                 return -1;
1632         }
1633         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1634         synchronize_rcu();
1635         kfree(old_qname);
1636         return 1;
1637 }
1638 #endif
1639
1640 #define MOPT_SET        0x0001
1641 #define MOPT_CLEAR      0x0002
1642 #define MOPT_NOSUPPORT  0x0004
1643 #define MOPT_EXPLICIT   0x0008
1644 #define MOPT_CLEAR_ERR  0x0010
1645 #define MOPT_GTE0       0x0020
1646 #ifdef CONFIG_QUOTA
1647 #define MOPT_Q          0
1648 #define MOPT_QFMT       0x0040
1649 #else
1650 #define MOPT_Q          MOPT_NOSUPPORT
1651 #define MOPT_QFMT       MOPT_NOSUPPORT
1652 #endif
1653 #define MOPT_DATAJ      0x0080
1654 #define MOPT_NO_EXT2    0x0100
1655 #define MOPT_NO_EXT3    0x0200
1656 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1657 #define MOPT_STRING     0x0400
1658
1659 static const struct mount_opts {
1660         int     token;
1661         int     mount_opt;
1662         int     flags;
1663 } ext4_mount_opts[] = {
1664         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1665         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1666         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1667         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1668         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1669         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1670         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1671          MOPT_EXT4_ONLY | MOPT_SET},
1672         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1673          MOPT_EXT4_ONLY | MOPT_CLEAR},
1674         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1675         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1676         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1677          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1678         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1679          MOPT_EXT4_ONLY | MOPT_CLEAR},
1680         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1681         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1682         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1683          MOPT_EXT4_ONLY | MOPT_CLEAR},
1684         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1685          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1686         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1687                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1688          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1689         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1690         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1691         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1692         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1693         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1694          MOPT_NO_EXT2},
1695         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1696          MOPT_NO_EXT2},
1697         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1698         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1699         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1700         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1701         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1702         {Opt_commit, 0, MOPT_GTE0},
1703         {Opt_max_batch_time, 0, MOPT_GTE0},
1704         {Opt_min_batch_time, 0, MOPT_GTE0},
1705         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1706         {Opt_init_itable, 0, MOPT_GTE0},
1707         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1708         {Opt_stripe, 0, MOPT_GTE0},
1709         {Opt_resuid, 0, MOPT_GTE0},
1710         {Opt_resgid, 0, MOPT_GTE0},
1711         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1712         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1713         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1714         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1715         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1716         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1717          MOPT_NO_EXT2 | MOPT_DATAJ},
1718         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1719         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1720 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1721         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1722         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1723 #else
1724         {Opt_acl, 0, MOPT_NOSUPPORT},
1725         {Opt_noacl, 0, MOPT_NOSUPPORT},
1726 #endif
1727         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1728         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1729         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1730         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1731         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1732                                                         MOPT_SET | MOPT_Q},
1733         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1734                                                         MOPT_SET | MOPT_Q},
1735         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1736                                                         MOPT_SET | MOPT_Q},
1737         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1738                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1739                                                         MOPT_CLEAR | MOPT_Q},
1740         {Opt_usrjquota, 0, MOPT_Q},
1741         {Opt_grpjquota, 0, MOPT_Q},
1742         {Opt_offusrjquota, 0, MOPT_Q},
1743         {Opt_offgrpjquota, 0, MOPT_Q},
1744         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1745         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1746         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1747         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1748         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1749         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1750         {Opt_err, 0, 0}
1751 };
1752
1753 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1754                             substring_t *args, unsigned long *journal_devnum,
1755                             unsigned int *journal_ioprio, int is_remount)
1756 {
1757         struct ext4_sb_info *sbi = EXT4_SB(sb);
1758         const struct mount_opts *m;
1759         kuid_t uid;
1760         kgid_t gid;
1761         int arg = 0;
1762
1763 #ifdef CONFIG_QUOTA
1764         if (token == Opt_usrjquota)
1765                 return set_qf_name(sb, USRQUOTA, &args[0]);
1766         else if (token == Opt_grpjquota)
1767                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1768         else if (token == Opt_offusrjquota)
1769                 return clear_qf_name(sb, USRQUOTA);
1770         else if (token == Opt_offgrpjquota)
1771                 return clear_qf_name(sb, GRPQUOTA);
1772 #endif
1773         switch (token) {
1774         case Opt_noacl:
1775         case Opt_nouser_xattr:
1776                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1777                 break;
1778         case Opt_sb:
1779                 return 1;       /* handled by get_sb_block() */
1780         case Opt_removed:
1781                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1782                 return 1;
1783         case Opt_abort:
1784                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1785                 return 1;
1786         case Opt_i_version:
1787                 sb->s_flags |= SB_I_VERSION;
1788                 return 1;
1789         case Opt_lazytime:
1790                 sb->s_flags |= SB_LAZYTIME;
1791                 return 1;
1792         case Opt_nolazytime:
1793                 sb->s_flags &= ~SB_LAZYTIME;
1794                 return 1;
1795         }
1796
1797         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1798                 if (token == m->token)
1799                         break;
1800
1801         if (m->token == Opt_err) {
1802                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1803                          "or missing value", opt);
1804                 return -1;
1805         }
1806
1807         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1808                 ext4_msg(sb, KERN_ERR,
1809                          "Mount option \"%s\" incompatible with ext2", opt);
1810                 return -1;
1811         }
1812         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1813                 ext4_msg(sb, KERN_ERR,
1814                          "Mount option \"%s\" incompatible with ext3", opt);
1815                 return -1;
1816         }
1817
1818         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1819                 return -1;
1820         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1821                 return -1;
1822         if (m->flags & MOPT_EXPLICIT) {
1823                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1824                         set_opt2(sb, EXPLICIT_DELALLOC);
1825                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1826                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1827                 } else
1828                         return -1;
1829         }
1830         if (m->flags & MOPT_CLEAR_ERR)
1831                 clear_opt(sb, ERRORS_MASK);
1832         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1833                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1834                          "options when quota turned on");
1835                 return -1;
1836         }
1837
1838         if (m->flags & MOPT_NOSUPPORT) {
1839                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1840         } else if (token == Opt_commit) {
1841                 if (arg == 0)
1842                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1843                 sbi->s_commit_interval = HZ * arg;
1844         } else if (token == Opt_debug_want_extra_isize) {
1845                 sbi->s_want_extra_isize = arg;
1846         } else if (token == Opt_max_batch_time) {
1847                 sbi->s_max_batch_time = arg;
1848         } else if (token == Opt_min_batch_time) {
1849                 sbi->s_min_batch_time = arg;
1850         } else if (token == Opt_inode_readahead_blks) {
1851                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1852                         ext4_msg(sb, KERN_ERR,
1853                                  "EXT4-fs: inode_readahead_blks must be "
1854                                  "0 or a power of 2 smaller than 2^31");
1855                         return -1;
1856                 }
1857                 sbi->s_inode_readahead_blks = arg;
1858         } else if (token == Opt_init_itable) {
1859                 set_opt(sb, INIT_INODE_TABLE);
1860                 if (!args->from)
1861                         arg = EXT4_DEF_LI_WAIT_MULT;
1862                 sbi->s_li_wait_mult = arg;
1863         } else if (token == Opt_max_dir_size_kb) {
1864                 sbi->s_max_dir_size_kb = arg;
1865         } else if (token == Opt_stripe) {
1866                 sbi->s_stripe = arg;
1867         } else if (token == Opt_resuid) {
1868                 uid = make_kuid(current_user_ns(), arg);
1869                 if (!uid_valid(uid)) {
1870                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1871                         return -1;
1872                 }
1873                 sbi->s_resuid = uid;
1874         } else if (token == Opt_resgid) {
1875                 gid = make_kgid(current_user_ns(), arg);
1876                 if (!gid_valid(gid)) {
1877                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1878                         return -1;
1879                 }
1880                 sbi->s_resgid = gid;
1881         } else if (token == Opt_journal_dev) {
1882                 if (is_remount) {
1883                         ext4_msg(sb, KERN_ERR,
1884                                  "Cannot specify journal on remount");
1885                         return -1;
1886                 }
1887                 *journal_devnum = arg;
1888         } else if (token == Opt_journal_path) {
1889                 char *journal_path;
1890                 struct inode *journal_inode;
1891                 struct path path;
1892                 int error;
1893
1894                 if (is_remount) {
1895                         ext4_msg(sb, KERN_ERR,
1896                                  "Cannot specify journal on remount");
1897                         return -1;
1898                 }
1899                 journal_path = match_strdup(&args[0]);
1900                 if (!journal_path) {
1901                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1902                                 "journal device string");
1903                         return -1;
1904                 }
1905
1906                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1907                 if (error) {
1908                         ext4_msg(sb, KERN_ERR, "error: could not find "
1909                                 "journal device path: error %d", error);
1910                         kfree(journal_path);
1911                         return -1;
1912                 }
1913
1914                 journal_inode = d_inode(path.dentry);
1915                 if (!S_ISBLK(journal_inode->i_mode)) {
1916                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1917                                 "is not a block device", journal_path);
1918                         path_put(&path);
1919                         kfree(journal_path);
1920                         return -1;
1921                 }
1922
1923                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1924                 path_put(&path);
1925                 kfree(journal_path);
1926         } else if (token == Opt_journal_ioprio) {
1927                 if (arg > 7) {
1928                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1929                                  " (must be 0-7)");
1930                         return -1;
1931                 }
1932                 *journal_ioprio =
1933                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1934         } else if (token == Opt_test_dummy_encryption) {
1935 #ifdef CONFIG_FS_ENCRYPTION
1936                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1937                 ext4_msg(sb, KERN_WARNING,
1938                          "Test dummy encryption mode enabled");
1939 #else
1940                 ext4_msg(sb, KERN_WARNING,
1941                          "Test dummy encryption mount option ignored");
1942 #endif
1943         } else if (m->flags & MOPT_DATAJ) {
1944                 if (is_remount) {
1945                         if (!sbi->s_journal)
1946                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1947                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1948                                 ext4_msg(sb, KERN_ERR,
1949                                          "Cannot change data mode on remount");
1950                                 return -1;
1951                         }
1952                 } else {
1953                         clear_opt(sb, DATA_FLAGS);
1954                         sbi->s_mount_opt |= m->mount_opt;
1955                 }
1956 #ifdef CONFIG_QUOTA
1957         } else if (m->flags & MOPT_QFMT) {
1958                 if (sb_any_quota_loaded(sb) &&
1959                     sbi->s_jquota_fmt != m->mount_opt) {
1960                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1961                                  "quota options when quota turned on");
1962                         return -1;
1963                 }
1964                 if (ext4_has_feature_quota(sb)) {
1965                         ext4_msg(sb, KERN_INFO,
1966                                  "Quota format mount options ignored "
1967                                  "when QUOTA feature is enabled");
1968                         return 1;
1969                 }
1970                 sbi->s_jquota_fmt = m->mount_opt;
1971 #endif
1972         } else if (token == Opt_dax) {
1973 #ifdef CONFIG_FS_DAX
1974                 ext4_msg(sb, KERN_WARNING,
1975                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
1976                 sbi->s_mount_opt |= m->mount_opt;
1977 #else
1978                 ext4_msg(sb, KERN_INFO, "dax option not supported");
1979                 return -1;
1980 #endif
1981         } else if (token == Opt_data_err_abort) {
1982                 sbi->s_mount_opt |= m->mount_opt;
1983         } else if (token == Opt_data_err_ignore) {
1984                 sbi->s_mount_opt &= ~m->mount_opt;
1985         } else {
1986                 if (!args->from)
1987                         arg = 1;
1988                 if (m->flags & MOPT_CLEAR)
1989                         arg = !arg;
1990                 else if (unlikely(!(m->flags & MOPT_SET))) {
1991                         ext4_msg(sb, KERN_WARNING,
1992                                  "buggy handling of option %s", opt);
1993                         WARN_ON(1);
1994                         return -1;
1995                 }
1996                 if (arg != 0)
1997                         sbi->s_mount_opt |= m->mount_opt;
1998                 else
1999                         sbi->s_mount_opt &= ~m->mount_opt;
2000         }
2001         return 1;
2002 }
2003
2004 static int parse_options(char *options, struct super_block *sb,
2005                          unsigned long *journal_devnum,
2006                          unsigned int *journal_ioprio,
2007                          int is_remount)
2008 {
2009         struct ext4_sb_info *sbi = EXT4_SB(sb);
2010         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2011         substring_t args[MAX_OPT_ARGS];
2012         int token;
2013
2014         if (!options)
2015                 return 1;
2016
2017         while ((p = strsep(&options, ",")) != NULL) {
2018                 if (!*p)
2019                         continue;
2020                 /*
2021                  * Initialize args struct so we know whether arg was
2022                  * found; some options take optional arguments.
2023                  */
2024                 args[0].to = args[0].from = NULL;
2025                 token = match_token(p, tokens, args);
2026                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2027                                      journal_ioprio, is_remount) < 0)
2028                         return 0;
2029         }
2030 #ifdef CONFIG_QUOTA
2031         /*
2032          * We do the test below only for project quotas. 'usrquota' and
2033          * 'grpquota' mount options are allowed even without quota feature
2034          * to support legacy quotas in quota files.
2035          */
2036         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2037                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2038                          "Cannot enable project quota enforcement.");
2039                 return 0;
2040         }
2041         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2042         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2043         if (usr_qf_name || grp_qf_name) {
2044                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2045                         clear_opt(sb, USRQUOTA);
2046
2047                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2048                         clear_opt(sb, GRPQUOTA);
2049
2050                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2051                         ext4_msg(sb, KERN_ERR, "old and new quota "
2052                                         "format mixing");
2053                         return 0;
2054                 }
2055
2056                 if (!sbi->s_jquota_fmt) {
2057                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2058                                         "not specified");
2059                         return 0;
2060                 }
2061         }
2062 #endif
2063         if (test_opt(sb, DIOREAD_NOLOCK)) {
2064                 int blocksize =
2065                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2066
2067                 if (blocksize < PAGE_SIZE) {
2068                         ext4_msg(sb, KERN_ERR, "can't mount with "
2069                                  "dioread_nolock if block size != PAGE_SIZE");
2070                         return 0;
2071                 }
2072         }
2073         return 1;
2074 }
2075
2076 static inline void ext4_show_quota_options(struct seq_file *seq,
2077                                            struct super_block *sb)
2078 {
2079 #if defined(CONFIG_QUOTA)
2080         struct ext4_sb_info *sbi = EXT4_SB(sb);
2081         char *usr_qf_name, *grp_qf_name;
2082
2083         if (sbi->s_jquota_fmt) {
2084                 char *fmtname = "";
2085
2086                 switch (sbi->s_jquota_fmt) {
2087                 case QFMT_VFS_OLD:
2088                         fmtname = "vfsold";
2089                         break;
2090                 case QFMT_VFS_V0:
2091                         fmtname = "vfsv0";
2092                         break;
2093                 case QFMT_VFS_V1:
2094                         fmtname = "vfsv1";
2095                         break;
2096                 }
2097                 seq_printf(seq, ",jqfmt=%s", fmtname);
2098         }
2099
2100         rcu_read_lock();
2101         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2102         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2103         if (usr_qf_name)
2104                 seq_show_option(seq, "usrjquota", usr_qf_name);
2105         if (grp_qf_name)
2106                 seq_show_option(seq, "grpjquota", grp_qf_name);
2107         rcu_read_unlock();
2108 #endif
2109 }
2110
2111 static const char *token2str(int token)
2112 {
2113         const struct match_token *t;
2114
2115         for (t = tokens; t->token != Opt_err; t++)
2116                 if (t->token == token && !strchr(t->pattern, '='))
2117                         break;
2118         return t->pattern;
2119 }
2120
2121 /*
2122  * Show an option if
2123  *  - it's set to a non-default value OR
2124  *  - if the per-sb default is different from the global default
2125  */
2126 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2127                               int nodefs)
2128 {
2129         struct ext4_sb_info *sbi = EXT4_SB(sb);
2130         struct ext4_super_block *es = sbi->s_es;
2131         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2132         const struct mount_opts *m;
2133         char sep = nodefs ? '\n' : ',';
2134
2135 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2136 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2137
2138         if (sbi->s_sb_block != 1)
2139                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2140
2141         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2142                 int want_set = m->flags & MOPT_SET;
2143                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2144                     (m->flags & MOPT_CLEAR_ERR))
2145                         continue;
2146                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2147                         continue; /* skip if same as the default */
2148                 if ((want_set &&
2149                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2150                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2151                         continue; /* select Opt_noFoo vs Opt_Foo */
2152                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2153         }
2154
2155         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2156             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2157                 SEQ_OPTS_PRINT("resuid=%u",
2158                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2159         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2160             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2161                 SEQ_OPTS_PRINT("resgid=%u",
2162                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2163         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2164         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2165                 SEQ_OPTS_PUTS("errors=remount-ro");
2166         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2167                 SEQ_OPTS_PUTS("errors=continue");
2168         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2169                 SEQ_OPTS_PUTS("errors=panic");
2170         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2171                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2172         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2173                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2174         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2175                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2176         if (sb->s_flags & SB_I_VERSION)
2177                 SEQ_OPTS_PUTS("i_version");
2178         if (nodefs || sbi->s_stripe)
2179                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2180         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2181                         (sbi->s_mount_opt ^ def_mount_opt)) {
2182                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2183                         SEQ_OPTS_PUTS("data=journal");
2184                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2185                         SEQ_OPTS_PUTS("data=ordered");
2186                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2187                         SEQ_OPTS_PUTS("data=writeback");
2188         }
2189         if (nodefs ||
2190             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2191                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2192                                sbi->s_inode_readahead_blks);
2193
2194         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2195                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2196                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2197         if (nodefs || sbi->s_max_dir_size_kb)
2198                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2199         if (test_opt(sb, DATA_ERR_ABORT))
2200                 SEQ_OPTS_PUTS("data_err=abort");
2201         if (DUMMY_ENCRYPTION_ENABLED(sbi))
2202                 SEQ_OPTS_PUTS("test_dummy_encryption");
2203
2204         ext4_show_quota_options(seq, sb);
2205         return 0;
2206 }
2207
2208 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2209 {
2210         return _ext4_show_options(seq, root->d_sb, 0);
2211 }
2212
2213 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2214 {
2215         struct super_block *sb = seq->private;
2216         int rc;
2217
2218         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2219         rc = _ext4_show_options(seq, sb, 1);
2220         seq_puts(seq, "\n");
2221         return rc;
2222 }
2223
2224 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2225                             int read_only)
2226 {
2227         struct ext4_sb_info *sbi = EXT4_SB(sb);
2228         int err = 0;
2229
2230         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2231                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2232                          "forcing read-only mode");
2233                 err = -EROFS;
2234         }
2235         if (read_only)
2236                 goto done;
2237         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2238                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2239                          "running e2fsck is recommended");
2240         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2241                 ext4_msg(sb, KERN_WARNING,
2242                          "warning: mounting fs with errors, "
2243                          "running e2fsck is recommended");
2244         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2245                  le16_to_cpu(es->s_mnt_count) >=
2246                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2247                 ext4_msg(sb, KERN_WARNING,
2248                          "warning: maximal mount count reached, "
2249                          "running e2fsck is recommended");
2250         else if (le32_to_cpu(es->s_checkinterval) &&
2251                  (ext4_get_tstamp(es, s_lastcheck) +
2252                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2253                 ext4_msg(sb, KERN_WARNING,
2254                          "warning: checktime reached, "
2255                          "running e2fsck is recommended");
2256         if (!sbi->s_journal)
2257                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2258         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2259                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2260         le16_add_cpu(&es->s_mnt_count, 1);
2261         ext4_update_tstamp(es, s_mtime);
2262         if (sbi->s_journal)
2263                 ext4_set_feature_journal_needs_recovery(sb);
2264
2265         err = ext4_commit_super(sb, 1);
2266 done:
2267         if (test_opt(sb, DEBUG))
2268                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2269                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2270                         sb->s_blocksize,
2271                         sbi->s_groups_count,
2272                         EXT4_BLOCKS_PER_GROUP(sb),
2273                         EXT4_INODES_PER_GROUP(sb),
2274                         sbi->s_mount_opt, sbi->s_mount_opt2);
2275
2276         cleancache_init_fs(sb);
2277         return err;
2278 }
2279
2280 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2281 {
2282         struct ext4_sb_info *sbi = EXT4_SB(sb);
2283         struct flex_groups *new_groups;
2284         int size;
2285
2286         if (!sbi->s_log_groups_per_flex)
2287                 return 0;
2288
2289         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2290         if (size <= sbi->s_flex_groups_allocated)
2291                 return 0;
2292
2293         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
2294         new_groups = kvzalloc(size, GFP_KERNEL);
2295         if (!new_groups) {
2296                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
2297                          size / (int) sizeof(struct flex_groups));
2298                 return -ENOMEM;
2299         }
2300
2301         if (sbi->s_flex_groups) {
2302                 memcpy(new_groups, sbi->s_flex_groups,
2303                        (sbi->s_flex_groups_allocated *
2304                         sizeof(struct flex_groups)));
2305                 kvfree(sbi->s_flex_groups);
2306         }
2307         sbi->s_flex_groups = new_groups;
2308         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
2309         return 0;
2310 }
2311
2312 static int ext4_fill_flex_info(struct super_block *sb)
2313 {
2314         struct ext4_sb_info *sbi = EXT4_SB(sb);
2315         struct ext4_group_desc *gdp = NULL;
2316         ext4_group_t flex_group;
2317         int i, err;
2318
2319         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2320         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2321                 sbi->s_log_groups_per_flex = 0;
2322                 return 1;
2323         }
2324
2325         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2326         if (err)
2327                 goto failed;
2328
2329         for (i = 0; i < sbi->s_groups_count; i++) {
2330                 gdp = ext4_get_group_desc(sb, i, NULL);
2331
2332                 flex_group = ext4_flex_group(sbi, i);
2333                 atomic_add(ext4_free_inodes_count(sb, gdp),
2334                            &sbi->s_flex_groups[flex_group].free_inodes);
2335                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2336                              &sbi->s_flex_groups[flex_group].free_clusters);
2337                 atomic_add(ext4_used_dirs_count(sb, gdp),
2338                            &sbi->s_flex_groups[flex_group].used_dirs);
2339         }
2340
2341         return 1;
2342 failed:
2343         return 0;
2344 }
2345
2346 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2347                                    struct ext4_group_desc *gdp)
2348 {
2349         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2350         __u16 crc = 0;
2351         __le32 le_group = cpu_to_le32(block_group);
2352         struct ext4_sb_info *sbi = EXT4_SB(sb);
2353
2354         if (ext4_has_metadata_csum(sbi->s_sb)) {
2355                 /* Use new metadata_csum algorithm */
2356                 __u32 csum32;
2357                 __u16 dummy_csum = 0;
2358
2359                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2360                                      sizeof(le_group));
2361                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2362                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2363                                      sizeof(dummy_csum));
2364                 offset += sizeof(dummy_csum);
2365                 if (offset < sbi->s_desc_size)
2366                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2367                                              sbi->s_desc_size - offset);
2368
2369                 crc = csum32 & 0xFFFF;
2370                 goto out;
2371         }
2372
2373         /* old crc16 code */
2374         if (!ext4_has_feature_gdt_csum(sb))
2375                 return 0;
2376
2377         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2378         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2379         crc = crc16(crc, (__u8 *)gdp, offset);
2380         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2381         /* for checksum of struct ext4_group_desc do the rest...*/
2382         if (ext4_has_feature_64bit(sb) &&
2383             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2384                 crc = crc16(crc, (__u8 *)gdp + offset,
2385                             le16_to_cpu(sbi->s_es->s_desc_size) -
2386                                 offset);
2387
2388 out:
2389         return cpu_to_le16(crc);
2390 }
2391
2392 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2393                                 struct ext4_group_desc *gdp)
2394 {
2395         if (ext4_has_group_desc_csum(sb) &&
2396             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2397                 return 0;
2398
2399         return 1;
2400 }
2401
2402 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2403                               struct ext4_group_desc *gdp)
2404 {
2405         if (!ext4_has_group_desc_csum(sb))
2406                 return;
2407         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2408 }
2409
2410 /* Called at mount-time, super-block is locked */
2411 static int ext4_check_descriptors(struct super_block *sb,
2412                                   ext4_fsblk_t sb_block,
2413                                   ext4_group_t *first_not_zeroed)
2414 {
2415         struct ext4_sb_info *sbi = EXT4_SB(sb);
2416         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2417         ext4_fsblk_t last_block;
2418         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2419         ext4_fsblk_t block_bitmap;
2420         ext4_fsblk_t inode_bitmap;
2421         ext4_fsblk_t inode_table;
2422         int flexbg_flag = 0;
2423         ext4_group_t i, grp = sbi->s_groups_count;
2424
2425         if (ext4_has_feature_flex_bg(sb))
2426                 flexbg_flag = 1;
2427
2428         ext4_debug("Checking group descriptors");
2429
2430         for (i = 0; i < sbi->s_groups_count; i++) {
2431                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2432
2433                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2434                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2435                 else
2436                         last_block = first_block +
2437                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2438
2439                 if ((grp == sbi->s_groups_count) &&
2440                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2441                         grp = i;
2442
2443                 block_bitmap = ext4_block_bitmap(sb, gdp);
2444                 if (block_bitmap == sb_block) {
2445                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2446                                  "Block bitmap for group %u overlaps "
2447                                  "superblock", i);
2448                         if (!sb_rdonly(sb))
2449                                 return 0;
2450                 }
2451                 if (block_bitmap >= sb_block + 1 &&
2452                     block_bitmap <= last_bg_block) {
2453                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2454                                  "Block bitmap for group %u overlaps "
2455                                  "block group descriptors", i);
2456                         if (!sb_rdonly(sb))
2457                                 return 0;
2458                 }
2459                 if (block_bitmap < first_block || block_bitmap > last_block) {
2460                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2461                                "Block bitmap for group %u not in group "
2462                                "(block %llu)!", i, block_bitmap);
2463                         return 0;
2464                 }
2465                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2466                 if (inode_bitmap == sb_block) {
2467                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2468                                  "Inode bitmap for group %u overlaps "
2469                                  "superblock", i);
2470                         if (!sb_rdonly(sb))
2471                                 return 0;
2472                 }
2473                 if (inode_bitmap >= sb_block + 1 &&
2474                     inode_bitmap <= last_bg_block) {
2475                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2476                                  "Inode bitmap for group %u overlaps "
2477                                  "block group descriptors", i);
2478                         if (!sb_rdonly(sb))
2479                                 return 0;
2480                 }
2481                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2482                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2483                                "Inode bitmap for group %u not in group "
2484                                "(block %llu)!", i, inode_bitmap);
2485                         return 0;
2486                 }
2487                 inode_table = ext4_inode_table(sb, gdp);
2488                 if (inode_table == sb_block) {
2489                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2490                                  "Inode table for group %u overlaps "
2491                                  "superblock", i);
2492                         if (!sb_rdonly(sb))
2493                                 return 0;
2494                 }
2495                 if (inode_table >= sb_block + 1 &&
2496                     inode_table <= last_bg_block) {
2497                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2498                                  "Inode table for group %u overlaps "
2499                                  "block group descriptors", i);
2500                         if (!sb_rdonly(sb))
2501                                 return 0;
2502                 }
2503                 if (inode_table < first_block ||
2504                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2505                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2506                                "Inode table for group %u not in group "
2507                                "(block %llu)!", i, inode_table);
2508                         return 0;
2509                 }
2510                 ext4_lock_group(sb, i);
2511                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2512                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2513                                  "Checksum for group %u failed (%u!=%u)",
2514                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2515                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2516                         if (!sb_rdonly(sb)) {
2517                                 ext4_unlock_group(sb, i);
2518                                 return 0;
2519                         }
2520                 }
2521                 ext4_unlock_group(sb, i);
2522                 if (!flexbg_flag)
2523                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2524         }
2525         if (NULL != first_not_zeroed)
2526                 *first_not_zeroed = grp;
2527         return 1;
2528 }
2529
2530 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2531  * the superblock) which were deleted from all directories, but held open by
2532  * a process at the time of a crash.  We walk the list and try to delete these
2533  * inodes at recovery time (only with a read-write filesystem).
2534  *
2535  * In order to keep the orphan inode chain consistent during traversal (in
2536  * case of crash during recovery), we link each inode into the superblock
2537  * orphan list_head and handle it the same way as an inode deletion during
2538  * normal operation (which journals the operations for us).
2539  *
2540  * We only do an iget() and an iput() on each inode, which is very safe if we
2541  * accidentally point at an in-use or already deleted inode.  The worst that
2542  * can happen in this case is that we get a "bit already cleared" message from
2543  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2544  * e2fsck was run on this filesystem, and it must have already done the orphan
2545  * inode cleanup for us, so we can safely abort without any further action.
2546  */
2547 static void ext4_orphan_cleanup(struct super_block *sb,
2548                                 struct ext4_super_block *es)
2549 {
2550         unsigned int s_flags = sb->s_flags;
2551         int ret, nr_orphans = 0, nr_truncates = 0;
2552 #ifdef CONFIG_QUOTA
2553         int quota_update = 0;
2554         int i;
2555 #endif
2556         if (!es->s_last_orphan) {
2557                 jbd_debug(4, "no orphan inodes to clean up\n");
2558                 return;
2559         }
2560
2561         if (bdev_read_only(sb->s_bdev)) {
2562                 ext4_msg(sb, KERN_ERR, "write access "
2563                         "unavailable, skipping orphan cleanup");
2564                 return;
2565         }
2566
2567         /* Check if feature set would not allow a r/w mount */
2568         if (!ext4_feature_set_ok(sb, 0)) {
2569                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2570                          "unknown ROCOMPAT features");
2571                 return;
2572         }
2573
2574         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2575                 /* don't clear list on RO mount w/ errors */
2576                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2577                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2578                                   "clearing orphan list.\n");
2579                         es->s_last_orphan = 0;
2580                 }
2581                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2582                 return;
2583         }
2584
2585         if (s_flags & SB_RDONLY) {
2586                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2587                 sb->s_flags &= ~SB_RDONLY;
2588         }
2589 #ifdef CONFIG_QUOTA
2590         /* Needed for iput() to work correctly and not trash data */
2591         sb->s_flags |= SB_ACTIVE;
2592
2593         /*
2594          * Turn on quotas which were not enabled for read-only mounts if
2595          * filesystem has quota feature, so that they are updated correctly.
2596          */
2597         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2598                 int ret = ext4_enable_quotas(sb);
2599
2600                 if (!ret)
2601                         quota_update = 1;
2602                 else
2603                         ext4_msg(sb, KERN_ERR,
2604                                 "Cannot turn on quotas: error %d", ret);
2605         }
2606
2607         /* Turn on journaled quotas used for old sytle */
2608         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2609                 if (EXT4_SB(sb)->s_qf_names[i]) {
2610                         int ret = ext4_quota_on_mount(sb, i);
2611
2612                         if (!ret)
2613                                 quota_update = 1;
2614                         else
2615                                 ext4_msg(sb, KERN_ERR,
2616                                         "Cannot turn on journaled "
2617                                         "quota: type %d: error %d", i, ret);
2618                 }
2619         }
2620 #endif
2621
2622         while (es->s_last_orphan) {
2623                 struct inode *inode;
2624
2625                 /*
2626                  * We may have encountered an error during cleanup; if
2627                  * so, skip the rest.
2628                  */
2629                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2630                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2631                         es->s_last_orphan = 0;
2632                         break;
2633                 }
2634
2635                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2636                 if (IS_ERR(inode)) {
2637                         es->s_last_orphan = 0;
2638                         break;
2639                 }
2640
2641                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2642                 dquot_initialize(inode);
2643                 if (inode->i_nlink) {
2644                         if (test_opt(sb, DEBUG))
2645                                 ext4_msg(sb, KERN_DEBUG,
2646                                         "%s: truncating inode %lu to %lld bytes",
2647                                         __func__, inode->i_ino, inode->i_size);
2648                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2649                                   inode->i_ino, inode->i_size);
2650                         inode_lock(inode);
2651                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2652                         ret = ext4_truncate(inode);
2653                         if (ret)
2654                                 ext4_std_error(inode->i_sb, ret);
2655                         inode_unlock(inode);
2656                         nr_truncates++;
2657                 } else {
2658                         if (test_opt(sb, DEBUG))
2659                                 ext4_msg(sb, KERN_DEBUG,
2660                                         "%s: deleting unreferenced inode %lu",
2661                                         __func__, inode->i_ino);
2662                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2663                                   inode->i_ino);
2664                         nr_orphans++;
2665                 }
2666                 iput(inode);  /* The delete magic happens here! */
2667         }
2668
2669 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2670
2671         if (nr_orphans)
2672                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2673                        PLURAL(nr_orphans));
2674         if (nr_truncates)
2675                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2676                        PLURAL(nr_truncates));
2677 #ifdef CONFIG_QUOTA
2678         /* Turn off quotas if they were enabled for orphan cleanup */
2679         if (quota_update) {
2680                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2681                         if (sb_dqopt(sb)->files[i])
2682                                 dquot_quota_off(sb, i);
2683                 }
2684         }
2685 #endif
2686         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2687 }
2688
2689 /*
2690  * Maximal extent format file size.
2691  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2692  * extent format containers, within a sector_t, and within i_blocks
2693  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2694  * so that won't be a limiting factor.
2695  *
2696  * However there is other limiting factor. We do store extents in the form
2697  * of starting block and length, hence the resulting length of the extent
2698  * covering maximum file size must fit into on-disk format containers as
2699  * well. Given that length is always by 1 unit bigger than max unit (because
2700  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2701  *
2702  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2703  */
2704 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2705 {
2706         loff_t res;
2707         loff_t upper_limit = MAX_LFS_FILESIZE;
2708
2709         /* small i_blocks in vfs inode? */
2710         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2711                 /*
2712                  * CONFIG_LBDAF is not enabled implies the inode
2713                  * i_block represent total blocks in 512 bytes
2714                  * 32 == size of vfs inode i_blocks * 8
2715                  */
2716                 upper_limit = (1LL << 32) - 1;
2717
2718                 /* total blocks in file system block size */
2719                 upper_limit >>= (blkbits - 9);
2720                 upper_limit <<= blkbits;
2721         }
2722
2723         /*
2724          * 32-bit extent-start container, ee_block. We lower the maxbytes
2725          * by one fs block, so ee_len can cover the extent of maximum file
2726          * size
2727          */
2728         res = (1LL << 32) - 1;
2729         res <<= blkbits;
2730
2731         /* Sanity check against vm- & vfs- imposed limits */
2732         if (res > upper_limit)
2733                 res = upper_limit;
2734
2735         return res;
2736 }
2737
2738 /*
2739  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2740  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2741  * We need to be 1 filesystem block less than the 2^48 sector limit.
2742  */
2743 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2744 {
2745         loff_t res = EXT4_NDIR_BLOCKS;
2746         int meta_blocks;
2747         loff_t upper_limit;
2748         /* This is calculated to be the largest file size for a dense, block
2749          * mapped file such that the file's total number of 512-byte sectors,
2750          * including data and all indirect blocks, does not exceed (2^48 - 1).
2751          *
2752          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2753          * number of 512-byte sectors of the file.
2754          */
2755
2756         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2757                 /*
2758                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2759                  * the inode i_block field represents total file blocks in
2760                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2761                  */
2762                 upper_limit = (1LL << 32) - 1;
2763
2764                 /* total blocks in file system block size */
2765                 upper_limit >>= (bits - 9);
2766
2767         } else {
2768                 /*
2769                  * We use 48 bit ext4_inode i_blocks
2770                  * With EXT4_HUGE_FILE_FL set the i_blocks
2771                  * represent total number of blocks in
2772                  * file system block size
2773                  */
2774                 upper_limit = (1LL << 48) - 1;
2775
2776         }
2777
2778         /* indirect blocks */
2779         meta_blocks = 1;
2780         /* double indirect blocks */
2781         meta_blocks += 1 + (1LL << (bits-2));
2782         /* tripple indirect blocks */
2783         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2784
2785         upper_limit -= meta_blocks;
2786         upper_limit <<= bits;
2787
2788         res += 1LL << (bits-2);
2789         res += 1LL << (2*(bits-2));
2790         res += 1LL << (3*(bits-2));
2791         res <<= bits;
2792         if (res > upper_limit)
2793                 res = upper_limit;
2794
2795         if (res > MAX_LFS_FILESIZE)
2796                 res = MAX_LFS_FILESIZE;
2797
2798         return res;
2799 }
2800
2801 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2802                                    ext4_fsblk_t logical_sb_block, int nr)
2803 {
2804         struct ext4_sb_info *sbi = EXT4_SB(sb);
2805         ext4_group_t bg, first_meta_bg;
2806         int has_super = 0;
2807
2808         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2809
2810         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2811                 return logical_sb_block + nr + 1;
2812         bg = sbi->s_desc_per_block * nr;
2813         if (ext4_bg_has_super(sb, bg))
2814                 has_super = 1;
2815
2816         /*
2817          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2818          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2819          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2820          * compensate.
2821          */
2822         if (sb->s_blocksize == 1024 && nr == 0 &&
2823             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
2824                 has_super++;
2825
2826         return (has_super + ext4_group_first_block_no(sb, bg));
2827 }
2828
2829 /**
2830  * ext4_get_stripe_size: Get the stripe size.
2831  * @sbi: In memory super block info
2832  *
2833  * If we have specified it via mount option, then
2834  * use the mount option value. If the value specified at mount time is
2835  * greater than the blocks per group use the super block value.
2836  * If the super block value is greater than blocks per group return 0.
2837  * Allocator needs it be less than blocks per group.
2838  *
2839  */
2840 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2841 {
2842         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2843         unsigned long stripe_width =
2844                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2845         int ret;
2846
2847         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2848                 ret = sbi->s_stripe;
2849         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2850                 ret = stripe_width;
2851         else if (stride && stride <= sbi->s_blocks_per_group)
2852                 ret = stride;
2853         else
2854                 ret = 0;
2855
2856         /*
2857          * If the stripe width is 1, this makes no sense and
2858          * we set it to 0 to turn off stripe handling code.
2859          */
2860         if (ret <= 1)
2861                 ret = 0;
2862
2863         return ret;
2864 }
2865
2866 /*
2867  * Check whether this filesystem can be mounted based on
2868  * the features present and the RDONLY/RDWR mount requested.
2869  * Returns 1 if this filesystem can be mounted as requested,
2870  * 0 if it cannot be.
2871  */
2872 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2873 {
2874         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2875                 ext4_msg(sb, KERN_ERR,
2876                         "Couldn't mount because of "
2877                         "unsupported optional features (%x)",
2878                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2879                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2880                 return 0;
2881         }
2882
2883         if (readonly)
2884                 return 1;
2885
2886         if (ext4_has_feature_readonly(sb)) {
2887                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2888                 sb->s_flags |= SB_RDONLY;
2889                 return 1;
2890         }
2891
2892         /* Check that feature set is OK for a read-write mount */
2893         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2894                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2895                          "unsupported optional features (%x)",
2896                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2897                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2898                 return 0;
2899         }
2900         /*
2901          * Large file size enabled file system can only be mounted
2902          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2903          */
2904         if (ext4_has_feature_huge_file(sb)) {
2905                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2906                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2907                                  "cannot be mounted RDWR without "
2908                                  "CONFIG_LBDAF");
2909                         return 0;
2910                 }
2911         }
2912         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2913                 ext4_msg(sb, KERN_ERR,
2914                          "Can't support bigalloc feature without "
2915                          "extents feature\n");
2916                 return 0;
2917         }
2918
2919 #ifndef CONFIG_QUOTA
2920         if (ext4_has_feature_quota(sb) && !readonly) {
2921                 ext4_msg(sb, KERN_ERR,
2922                          "Filesystem with quota feature cannot be mounted RDWR "
2923                          "without CONFIG_QUOTA");
2924                 return 0;
2925         }
2926         if (ext4_has_feature_project(sb) && !readonly) {
2927                 ext4_msg(sb, KERN_ERR,
2928                          "Filesystem with project quota feature cannot be mounted RDWR "
2929                          "without CONFIG_QUOTA");
2930                 return 0;
2931         }
2932 #endif  /* CONFIG_QUOTA */
2933         return 1;
2934 }
2935
2936 /*
2937  * This function is called once a day if we have errors logged
2938  * on the file system
2939  */
2940 static void print_daily_error_info(struct timer_list *t)
2941 {
2942         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
2943         struct super_block *sb = sbi->s_sb;
2944         struct ext4_super_block *es = sbi->s_es;
2945
2946         if (es->s_error_count)
2947                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2948                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2949                          le32_to_cpu(es->s_error_count));
2950         if (es->s_first_error_time) {
2951                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
2952                        sb->s_id,
2953                        ext4_get_tstamp(es, s_first_error_time),
2954                        (int) sizeof(es->s_first_error_func),
2955                        es->s_first_error_func,
2956                        le32_to_cpu(es->s_first_error_line));
2957                 if (es->s_first_error_ino)
2958                         printk(KERN_CONT ": inode %u",
2959                                le32_to_cpu(es->s_first_error_ino));
2960                 if (es->s_first_error_block)
2961                         printk(KERN_CONT ": block %llu", (unsigned long long)
2962                                le64_to_cpu(es->s_first_error_block));
2963                 printk(KERN_CONT "\n");
2964         }
2965         if (es->s_last_error_time) {
2966                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
2967                        sb->s_id,
2968                        ext4_get_tstamp(es, s_last_error_time),
2969                        (int) sizeof(es->s_last_error_func),
2970                        es->s_last_error_func,
2971                        le32_to_cpu(es->s_last_error_line));
2972                 if (es->s_last_error_ino)
2973                         printk(KERN_CONT ": inode %u",
2974                                le32_to_cpu(es->s_last_error_ino));
2975                 if (es->s_last_error_block)
2976                         printk(KERN_CONT ": block %llu", (unsigned long long)
2977                                le64_to_cpu(es->s_last_error_block));
2978                 printk(KERN_CONT "\n");
2979         }
2980         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2981 }
2982
2983 /* Find next suitable group and run ext4_init_inode_table */
2984 static int ext4_run_li_request(struct ext4_li_request *elr)
2985 {
2986         struct ext4_group_desc *gdp = NULL;
2987         ext4_group_t group, ngroups;
2988         struct super_block *sb;
2989         unsigned long timeout = 0;
2990         int ret = 0;
2991
2992         sb = elr->lr_super;
2993         ngroups = EXT4_SB(sb)->s_groups_count;
2994
2995         for (group = elr->lr_next_group; group < ngroups; group++) {
2996                 gdp = ext4_get_group_desc(sb, group, NULL);
2997                 if (!gdp) {
2998                         ret = 1;
2999                         break;
3000                 }
3001
3002                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3003                         break;
3004         }
3005
3006         if (group >= ngroups)
3007                 ret = 1;
3008
3009         if (!ret) {
3010                 timeout = jiffies;
3011                 ret = ext4_init_inode_table(sb, group,
3012                                             elr->lr_timeout ? 0 : 1);
3013                 if (elr->lr_timeout == 0) {
3014                         timeout = (jiffies - timeout) *
3015                                   elr->lr_sbi->s_li_wait_mult;
3016                         elr->lr_timeout = timeout;
3017                 }
3018                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3019                 elr->lr_next_group = group + 1;
3020         }
3021         return ret;
3022 }
3023
3024 /*
3025  * Remove lr_request from the list_request and free the
3026  * request structure. Should be called with li_list_mtx held
3027  */
3028 static void ext4_remove_li_request(struct ext4_li_request *elr)
3029 {
3030         struct ext4_sb_info *sbi;
3031
3032         if (!elr)
3033                 return;
3034
3035         sbi = elr->lr_sbi;
3036
3037         list_del(&elr->lr_request);
3038         sbi->s_li_request = NULL;
3039         kfree(elr);
3040 }
3041
3042 static void ext4_unregister_li_request(struct super_block *sb)
3043 {
3044         mutex_lock(&ext4_li_mtx);
3045         if (!ext4_li_info) {
3046                 mutex_unlock(&ext4_li_mtx);
3047                 return;
3048         }
3049
3050         mutex_lock(&ext4_li_info->li_list_mtx);
3051         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3052         mutex_unlock(&ext4_li_info->li_list_mtx);
3053         mutex_unlock(&ext4_li_mtx);
3054 }
3055
3056 static struct task_struct *ext4_lazyinit_task;
3057
3058 /*
3059  * This is the function where ext4lazyinit thread lives. It walks
3060  * through the request list searching for next scheduled filesystem.
3061  * When such a fs is found, run the lazy initialization request
3062  * (ext4_rn_li_request) and keep track of the time spend in this
3063  * function. Based on that time we compute next schedule time of
3064  * the request. When walking through the list is complete, compute
3065  * next waking time and put itself into sleep.
3066  */
3067 static int ext4_lazyinit_thread(void *arg)
3068 {
3069         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3070         struct list_head *pos, *n;
3071         struct ext4_li_request *elr;
3072         unsigned long next_wakeup, cur;
3073
3074         BUG_ON(NULL == eli);
3075
3076 cont_thread:
3077         while (true) {
3078                 next_wakeup = MAX_JIFFY_OFFSET;
3079
3080                 mutex_lock(&eli->li_list_mtx);
3081                 if (list_empty(&eli->li_request_list)) {
3082                         mutex_unlock(&eli->li_list_mtx);
3083                         goto exit_thread;
3084                 }
3085                 list_for_each_safe(pos, n, &eli->li_request_list) {
3086                         int err = 0;
3087                         int progress = 0;
3088                         elr = list_entry(pos, struct ext4_li_request,
3089                                          lr_request);
3090
3091                         if (time_before(jiffies, elr->lr_next_sched)) {
3092                                 if (time_before(elr->lr_next_sched, next_wakeup))
3093                                         next_wakeup = elr->lr_next_sched;
3094                                 continue;
3095                         }
3096                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3097                                 if (sb_start_write_trylock(elr->lr_super)) {
3098                                         progress = 1;
3099                                         /*
3100                                          * We hold sb->s_umount, sb can not
3101                                          * be removed from the list, it is
3102                                          * now safe to drop li_list_mtx
3103                                          */
3104                                         mutex_unlock(&eli->li_list_mtx);
3105                                         err = ext4_run_li_request(elr);
3106                                         sb_end_write(elr->lr_super);
3107                                         mutex_lock(&eli->li_list_mtx);
3108                                         n = pos->next;
3109                                 }
3110                                 up_read((&elr->lr_super->s_umount));
3111                         }
3112                         /* error, remove the lazy_init job */
3113                         if (err) {
3114                                 ext4_remove_li_request(elr);
3115                                 continue;
3116                         }
3117                         if (!progress) {
3118                                 elr->lr_next_sched = jiffies +
3119                                         (prandom_u32()
3120                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3121                         }
3122                         if (time_before(elr->lr_next_sched, next_wakeup))
3123                                 next_wakeup = elr->lr_next_sched;
3124                 }
3125                 mutex_unlock(&eli->li_list_mtx);
3126
3127                 try_to_freeze();
3128
3129                 cur = jiffies;
3130                 if ((time_after_eq(cur, next_wakeup)) ||
3131                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3132                         cond_resched();
3133                         continue;
3134                 }
3135
3136                 schedule_timeout_interruptible(next_wakeup - cur);
3137
3138                 if (kthread_should_stop()) {
3139                         ext4_clear_request_list();
3140                         goto exit_thread;
3141                 }
3142         }
3143
3144 exit_thread:
3145         /*
3146          * It looks like the request list is empty, but we need
3147          * to check it under the li_list_mtx lock, to prevent any
3148          * additions into it, and of course we should lock ext4_li_mtx
3149          * to atomically free the list and ext4_li_info, because at
3150          * this point another ext4 filesystem could be registering
3151          * new one.
3152          */
3153         mutex_lock(&ext4_li_mtx);
3154         mutex_lock(&eli->li_list_mtx);
3155         if (!list_empty(&eli->li_request_list)) {
3156                 mutex_unlock(&eli->li_list_mtx);
3157                 mutex_unlock(&ext4_li_mtx);
3158                 goto cont_thread;
3159         }
3160         mutex_unlock(&eli->li_list_mtx);
3161         kfree(ext4_li_info);
3162         ext4_li_info = NULL;
3163         mutex_unlock(&ext4_li_mtx);
3164
3165         return 0;
3166 }
3167
3168 static void ext4_clear_request_list(void)
3169 {
3170         struct list_head *pos, *n;
3171         struct ext4_li_request *elr;
3172
3173         mutex_lock(&ext4_li_info->li_list_mtx);
3174         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3175                 elr = list_entry(pos, struct ext4_li_request,
3176                                  lr_request);
3177                 ext4_remove_li_request(elr);
3178         }
3179         mutex_unlock(&ext4_li_info->li_list_mtx);
3180 }
3181
3182 static int ext4_run_lazyinit_thread(void)
3183 {
3184         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3185                                          ext4_li_info, "ext4lazyinit");
3186         if (IS_ERR(ext4_lazyinit_task)) {
3187                 int err = PTR_ERR(ext4_lazyinit_task);
3188                 ext4_clear_request_list();
3189                 kfree(ext4_li_info);
3190                 ext4_li_info = NULL;
3191                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3192                                  "initialization thread\n",
3193                                  err);
3194                 return err;
3195         }
3196         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3197         return 0;
3198 }
3199
3200 /*
3201  * Check whether it make sense to run itable init. thread or not.
3202  * If there is at least one uninitialized inode table, return
3203  * corresponding group number, else the loop goes through all
3204  * groups and return total number of groups.
3205  */
3206 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3207 {
3208         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3209         struct ext4_group_desc *gdp = NULL;
3210
3211         if (!ext4_has_group_desc_csum(sb))
3212                 return ngroups;
3213
3214         for (group = 0; group < ngroups; group++) {
3215                 gdp = ext4_get_group_desc(sb, group, NULL);
3216                 if (!gdp)
3217                         continue;
3218
3219                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3220                         break;
3221         }
3222
3223         return group;
3224 }
3225
3226 static int ext4_li_info_new(void)
3227 {
3228         struct ext4_lazy_init *eli = NULL;
3229
3230         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3231         if (!eli)
3232                 return -ENOMEM;
3233
3234         INIT_LIST_HEAD(&eli->li_request_list);
3235         mutex_init(&eli->li_list_mtx);
3236
3237         eli->li_state |= EXT4_LAZYINIT_QUIT;
3238
3239         ext4_li_info = eli;
3240
3241         return 0;
3242 }
3243
3244 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3245                                             ext4_group_t start)
3246 {
3247         struct ext4_sb_info *sbi = EXT4_SB(sb);
3248         struct ext4_li_request *elr;
3249
3250         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3251         if (!elr)
3252                 return NULL;
3253
3254         elr->lr_super = sb;
3255         elr->lr_sbi = sbi;
3256         elr->lr_next_group = start;
3257
3258         /*
3259          * Randomize first schedule time of the request to
3260          * spread the inode table initialization requests
3261          * better.
3262          */
3263         elr->lr_next_sched = jiffies + (prandom_u32() %
3264                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3265         return elr;
3266 }
3267
3268 int ext4_register_li_request(struct super_block *sb,
3269                              ext4_group_t first_not_zeroed)
3270 {
3271         struct ext4_sb_info *sbi = EXT4_SB(sb);
3272         struct ext4_li_request *elr = NULL;
3273         ext4_group_t ngroups = sbi->s_groups_count;
3274         int ret = 0;
3275
3276         mutex_lock(&ext4_li_mtx);
3277         if (sbi->s_li_request != NULL) {
3278                 /*
3279                  * Reset timeout so it can be computed again, because
3280                  * s_li_wait_mult might have changed.
3281                  */
3282                 sbi->s_li_request->lr_timeout = 0;
3283                 goto out;
3284         }
3285
3286         if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3287             !test_opt(sb, INIT_INODE_TABLE))
3288                 goto out;
3289
3290         elr = ext4_li_request_new(sb, first_not_zeroed);
3291         if (!elr) {
3292                 ret = -ENOMEM;
3293                 goto out;
3294         }
3295
3296         if (NULL == ext4_li_info) {
3297                 ret = ext4_li_info_new();
3298                 if (ret)
3299                         goto out;
3300         }
3301
3302         mutex_lock(&ext4_li_info->li_list_mtx);
3303         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3304         mutex_unlock(&ext4_li_info->li_list_mtx);
3305
3306         sbi->s_li_request = elr;
3307         /*
3308          * set elr to NULL here since it has been inserted to
3309          * the request_list and the removal and free of it is
3310          * handled by ext4_clear_request_list from now on.
3311          */
3312         elr = NULL;
3313
3314         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3315                 ret = ext4_run_lazyinit_thread();
3316                 if (ret)
3317                         goto out;
3318         }
3319 out:
3320         mutex_unlock(&ext4_li_mtx);
3321         if (ret)
3322                 kfree(elr);
3323         return ret;
3324 }
3325
3326 /*
3327  * We do not need to lock anything since this is called on
3328  * module unload.
3329  */
3330 static void ext4_destroy_lazyinit_thread(void)
3331 {
3332         /*
3333          * If thread exited earlier
3334          * there's nothing to be done.
3335          */
3336         if (!ext4_li_info || !ext4_lazyinit_task)
3337                 return;
3338
3339         kthread_stop(ext4_lazyinit_task);
3340 }
3341
3342 static int set_journal_csum_feature_set(struct super_block *sb)
3343 {
3344         int ret = 1;
3345         int compat, incompat;
3346         struct ext4_sb_info *sbi = EXT4_SB(sb);
3347
3348         if (ext4_has_metadata_csum(sb)) {
3349                 /* journal checksum v3 */
3350                 compat = 0;
3351                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3352         } else {
3353                 /* journal checksum v1 */
3354                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3355                 incompat = 0;
3356         }
3357
3358         jbd2_journal_clear_features(sbi->s_journal,
3359                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3360                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3361                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3362         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3363                 ret = jbd2_journal_set_features(sbi->s_journal,
3364                                 compat, 0,
3365                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3366                                 incompat);
3367         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3368                 ret = jbd2_journal_set_features(sbi->s_journal,
3369                                 compat, 0,
3370                                 incompat);
3371                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3372                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3373         } else {
3374                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3375                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3376         }
3377
3378         return ret;
3379 }
3380
3381 /*
3382  * Note: calculating the overhead so we can be compatible with
3383  * historical BSD practice is quite difficult in the face of
3384  * clusters/bigalloc.  This is because multiple metadata blocks from
3385  * different block group can end up in the same allocation cluster.
3386  * Calculating the exact overhead in the face of clustered allocation
3387  * requires either O(all block bitmaps) in memory or O(number of block
3388  * groups**2) in time.  We will still calculate the superblock for
3389  * older file systems --- and if we come across with a bigalloc file
3390  * system with zero in s_overhead_clusters the estimate will be close to
3391  * correct especially for very large cluster sizes --- but for newer
3392  * file systems, it's better to calculate this figure once at mkfs
3393  * time, and store it in the superblock.  If the superblock value is
3394  * present (even for non-bigalloc file systems), we will use it.
3395  */
3396 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3397                           char *buf)
3398 {
3399         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3400         struct ext4_group_desc  *gdp;
3401         ext4_fsblk_t            first_block, last_block, b;
3402         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3403         int                     s, j, count = 0;
3404
3405         if (!ext4_has_feature_bigalloc(sb))
3406                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3407                         sbi->s_itb_per_group + 2);
3408
3409         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3410                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3411         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3412         for (i = 0; i < ngroups; i++) {
3413                 gdp = ext4_get_group_desc(sb, i, NULL);
3414                 b = ext4_block_bitmap(sb, gdp);
3415                 if (b >= first_block && b <= last_block) {
3416                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3417                         count++;
3418                 }
3419                 b = ext4_inode_bitmap(sb, gdp);
3420                 if (b >= first_block && b <= last_block) {
3421                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3422                         count++;
3423                 }
3424                 b = ext4_inode_table(sb, gdp);
3425                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3426                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3427                                 int c = EXT4_B2C(sbi, b - first_block);
3428                                 ext4_set_bit(c, buf);
3429                                 count++;
3430                         }
3431                 if (i != grp)
3432                         continue;
3433                 s = 0;
3434                 if (ext4_bg_has_super(sb, grp)) {
3435                         ext4_set_bit(s++, buf);
3436                         count++;
3437                 }
3438                 j = ext4_bg_num_gdb(sb, grp);
3439                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3440                         ext4_error(sb, "Invalid number of block group "
3441                                    "descriptor blocks: %d", j);
3442                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3443                 }
3444                 count += j;
3445                 for (; j > 0; j--)
3446                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3447         }
3448         if (!count)
3449                 return 0;
3450         return EXT4_CLUSTERS_PER_GROUP(sb) -
3451                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3452 }
3453
3454 /*
3455  * Compute the overhead and stash it in sbi->s_overhead
3456  */
3457 int ext4_calculate_overhead(struct super_block *sb)
3458 {
3459         struct ext4_sb_info *sbi = EXT4_SB(sb);
3460         struct ext4_super_block *es = sbi->s_es;
3461         struct inode *j_inode;
3462         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3463         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3464         ext4_fsblk_t overhead = 0;
3465         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3466
3467         if (!buf)
3468                 return -ENOMEM;
3469
3470         /*
3471          * Compute the overhead (FS structures).  This is constant
3472          * for a given filesystem unless the number of block groups
3473          * changes so we cache the previous value until it does.
3474          */
3475
3476         /*
3477          * All of the blocks before first_data_block are overhead
3478          */
3479         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3480
3481         /*
3482          * Add the overhead found in each block group
3483          */
3484         for (i = 0; i < ngroups; i++) {
3485                 int blks;
3486
3487                 blks = count_overhead(sb, i, buf);
3488                 overhead += blks;
3489                 if (blks)
3490                         memset(buf, 0, PAGE_SIZE);
3491                 cond_resched();
3492         }
3493
3494         /*
3495          * Add the internal journal blocks whether the journal has been
3496          * loaded or not
3497          */
3498         if (sbi->s_journal && !sbi->journal_bdev)
3499                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3500         else if (ext4_has_feature_journal(sb) && !sbi->s_journal) {
3501                 j_inode = ext4_get_journal_inode(sb, j_inum);
3502                 if (j_inode) {
3503                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3504                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3505                         iput(j_inode);
3506                 } else {
3507                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3508                 }
3509         }
3510         sbi->s_overhead = overhead;
3511         smp_wmb();
3512         free_page((unsigned long) buf);
3513         return 0;
3514 }
3515
3516 static void ext4_set_resv_clusters(struct super_block *sb)
3517 {
3518         ext4_fsblk_t resv_clusters;
3519         struct ext4_sb_info *sbi = EXT4_SB(sb);
3520
3521         /*
3522          * There's no need to reserve anything when we aren't using extents.
3523          * The space estimates are exact, there are no unwritten extents,
3524          * hole punching doesn't need new metadata... This is needed especially
3525          * to keep ext2/3 backward compatibility.
3526          */
3527         if (!ext4_has_feature_extents(sb))
3528                 return;
3529         /*
3530          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3531          * This should cover the situations where we can not afford to run
3532          * out of space like for example punch hole, or converting
3533          * unwritten extents in delalloc path. In most cases such
3534          * allocation would require 1, or 2 blocks, higher numbers are
3535          * very rare.
3536          */
3537         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3538                          sbi->s_cluster_bits);
3539
3540         do_div(resv_clusters, 50);
3541         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3542
3543         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3544 }
3545
3546 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3547 {
3548         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3549         char *orig_data = kstrdup(data, GFP_KERNEL);
3550         struct buffer_head *bh;
3551         struct ext4_super_block *es = NULL;
3552         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3553         ext4_fsblk_t block;
3554         ext4_fsblk_t sb_block = get_sb_block(&data);
3555         ext4_fsblk_t logical_sb_block;
3556         unsigned long offset = 0;
3557         unsigned long journal_devnum = 0;
3558         unsigned long def_mount_opts;
3559         struct inode *root;
3560         const char *descr;
3561         int ret = -ENOMEM;
3562         int blocksize, clustersize;
3563         unsigned int db_count;
3564         unsigned int i;
3565         int needs_recovery, has_huge_files, has_bigalloc;
3566         __u64 blocks_count;
3567         int err = 0;
3568         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3569         ext4_group_t first_not_zeroed;
3570
3571         if ((data && !orig_data) || !sbi)
3572                 goto out_free_base;
3573
3574         sbi->s_daxdev = dax_dev;
3575         sbi->s_blockgroup_lock =
3576                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3577         if (!sbi->s_blockgroup_lock)
3578                 goto out_free_base;
3579
3580         sb->s_fs_info = sbi;
3581         sbi->s_sb = sb;
3582         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3583         sbi->s_sb_block = sb_block;
3584         if (sb->s_bdev->bd_part)
3585                 sbi->s_sectors_written_start =
3586                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
3587
3588         /* Cleanup superblock name */
3589         strreplace(sb->s_id, '/', '!');
3590
3591         /* -EINVAL is default */
3592         ret = -EINVAL;
3593         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3594         if (!blocksize) {
3595                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3596                 goto out_fail;
3597         }
3598
3599         /*
3600          * The ext4 superblock will not be buffer aligned for other than 1kB
3601          * block sizes.  We need to calculate the offset from buffer start.
3602          */
3603         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3604                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3605                 offset = do_div(logical_sb_block, blocksize);
3606         } else {
3607                 logical_sb_block = sb_block;
3608         }
3609
3610         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3611                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3612                 goto out_fail;
3613         }
3614         /*
3615          * Note: s_es must be initialized as soon as possible because
3616          *       some ext4 macro-instructions depend on its value
3617          */
3618         es = (struct ext4_super_block *) (bh->b_data + offset);
3619         sbi->s_es = es;
3620         sb->s_magic = le16_to_cpu(es->s_magic);
3621         if (sb->s_magic != EXT4_SUPER_MAGIC)
3622                 goto cantfind_ext4;
3623         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3624
3625         /* Warn if metadata_csum and gdt_csum are both set. */
3626         if (ext4_has_feature_metadata_csum(sb) &&
3627             ext4_has_feature_gdt_csum(sb))
3628                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3629                              "redundant flags; please run fsck.");
3630
3631         /* Check for a known checksum algorithm */
3632         if (!ext4_verify_csum_type(sb, es)) {
3633                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3634                          "unknown checksum algorithm.");
3635                 silent = 1;
3636                 goto cantfind_ext4;
3637         }
3638
3639         /* Load the checksum driver */
3640         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3641         if (IS_ERR(sbi->s_chksum_driver)) {
3642                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3643                 ret = PTR_ERR(sbi->s_chksum_driver);
3644                 sbi->s_chksum_driver = NULL;
3645                 goto failed_mount;
3646         }
3647
3648         /* Check superblock checksum */
3649         if (!ext4_superblock_csum_verify(sb, es)) {
3650                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3651                          "invalid superblock checksum.  Run e2fsck?");
3652                 silent = 1;
3653                 ret = -EFSBADCRC;
3654                 goto cantfind_ext4;
3655         }
3656
3657         /* Precompute checksum seed for all metadata */
3658         if (ext4_has_feature_csum_seed(sb))
3659                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3660         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3661                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3662                                                sizeof(es->s_uuid));
3663
3664         /* Set defaults before we parse the mount options */
3665         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3666         set_opt(sb, INIT_INODE_TABLE);
3667         if (def_mount_opts & EXT4_DEFM_DEBUG)
3668                 set_opt(sb, DEBUG);
3669         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3670                 set_opt(sb, GRPID);
3671         if (def_mount_opts & EXT4_DEFM_UID16)
3672                 set_opt(sb, NO_UID32);
3673         /* xattr user namespace & acls are now defaulted on */
3674         set_opt(sb, XATTR_USER);
3675 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3676         set_opt(sb, POSIX_ACL);
3677 #endif
3678         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3679         if (ext4_has_metadata_csum(sb))
3680                 set_opt(sb, JOURNAL_CHECKSUM);
3681
3682         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3683                 set_opt(sb, JOURNAL_DATA);
3684         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3685                 set_opt(sb, ORDERED_DATA);
3686         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3687                 set_opt(sb, WRITEBACK_DATA);
3688
3689         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3690                 set_opt(sb, ERRORS_PANIC);
3691         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3692                 set_opt(sb, ERRORS_CONT);
3693         else
3694                 set_opt(sb, ERRORS_RO);
3695         /* block_validity enabled by default; disable with noblock_validity */
3696         set_opt(sb, BLOCK_VALIDITY);
3697         if (def_mount_opts & EXT4_DEFM_DISCARD)
3698                 set_opt(sb, DISCARD);
3699
3700         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3701         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3702         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3703         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3704         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3705
3706         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3707                 set_opt(sb, BARRIER);
3708
3709         /*
3710          * enable delayed allocation by default
3711          * Use -o nodelalloc to turn it off
3712          */
3713         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3714             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3715                 set_opt(sb, DELALLOC);
3716
3717         /*
3718          * set default s_li_wait_mult for lazyinit, for the case there is
3719          * no mount option specified.
3720          */
3721         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3722
3723         if (sbi->s_es->s_mount_opts[0]) {
3724                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3725                                               sizeof(sbi->s_es->s_mount_opts),
3726                                               GFP_KERNEL);
3727                 if (!s_mount_opts)
3728                         goto failed_mount;
3729                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
3730                                    &journal_ioprio, 0)) {
3731                         ext4_msg(sb, KERN_WARNING,
3732                                  "failed to parse options in superblock: %s",
3733                                  s_mount_opts);
3734                 }
3735                 kfree(s_mount_opts);
3736         }
3737         sbi->s_def_mount_opt = sbi->s_mount_opt;
3738         if (!parse_options((char *) data, sb, &journal_devnum,
3739                            &journal_ioprio, 0))
3740                 goto failed_mount;
3741
3742         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3743                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3744                             "with data=journal disables delayed "
3745                             "allocation and O_DIRECT support!\n");
3746                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3747                         ext4_msg(sb, KERN_ERR, "can't mount with "
3748                                  "both data=journal and delalloc");
3749                         goto failed_mount;
3750                 }
3751                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3752                         ext4_msg(sb, KERN_ERR, "can't mount with "
3753                                  "both data=journal and dioread_nolock");
3754                         goto failed_mount;
3755                 }
3756                 if (test_opt(sb, DAX)) {
3757                         ext4_msg(sb, KERN_ERR, "can't mount with "
3758                                  "both data=journal and dax");
3759                         goto failed_mount;
3760                 }
3761                 if (ext4_has_feature_encrypt(sb)) {
3762                         ext4_msg(sb, KERN_WARNING,
3763                                  "encrypted files will use data=ordered "
3764                                  "instead of data journaling mode");
3765                 }
3766                 if (test_opt(sb, DELALLOC))
3767                         clear_opt(sb, DELALLOC);
3768         } else {
3769                 sb->s_iflags |= SB_I_CGROUPWB;
3770         }
3771
3772         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
3773                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
3774
3775         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3776             (ext4_has_compat_features(sb) ||
3777              ext4_has_ro_compat_features(sb) ||
3778              ext4_has_incompat_features(sb)))
3779                 ext4_msg(sb, KERN_WARNING,
3780                        "feature flags set on rev 0 fs, "
3781                        "running e2fsck is recommended");
3782
3783         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3784                 set_opt2(sb, HURD_COMPAT);
3785                 if (ext4_has_feature_64bit(sb)) {
3786                         ext4_msg(sb, KERN_ERR,
3787                                  "The Hurd can't support 64-bit file systems");
3788                         goto failed_mount;
3789                 }
3790
3791                 /*
3792                  * ea_inode feature uses l_i_version field which is not
3793                  * available in HURD_COMPAT mode.
3794                  */
3795                 if (ext4_has_feature_ea_inode(sb)) {
3796                         ext4_msg(sb, KERN_ERR,
3797                                  "ea_inode feature is not supported for Hurd");
3798                         goto failed_mount;
3799                 }
3800         }
3801
3802         if (IS_EXT2_SB(sb)) {
3803                 if (ext2_feature_set_ok(sb))
3804                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3805                                  "using the ext4 subsystem");
3806                 else {
3807                         /*
3808                          * If we're probing be silent, if this looks like
3809                          * it's actually an ext[34] filesystem.
3810                          */
3811                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3812                                 goto failed_mount;
3813                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3814                                  "to feature incompatibilities");
3815                         goto failed_mount;
3816                 }
3817         }
3818
3819         if (IS_EXT3_SB(sb)) {
3820                 if (ext3_feature_set_ok(sb))
3821                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3822                                  "using the ext4 subsystem");
3823                 else {
3824                         /*
3825                          * If we're probing be silent, if this looks like
3826                          * it's actually an ext4 filesystem.
3827                          */
3828                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3829                                 goto failed_mount;
3830                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3831                                  "to feature incompatibilities");
3832                         goto failed_mount;
3833                 }
3834         }
3835
3836         /*
3837          * Check feature flags regardless of the revision level, since we
3838          * previously didn't change the revision level when setting the flags,
3839          * so there is a chance incompat flags are set on a rev 0 filesystem.
3840          */
3841         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
3842                 goto failed_mount;
3843
3844         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3845         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3846             blocksize > EXT4_MAX_BLOCK_SIZE) {
3847                 ext4_msg(sb, KERN_ERR,
3848                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3849                          blocksize, le32_to_cpu(es->s_log_block_size));
3850                 goto failed_mount;
3851         }
3852         if (le32_to_cpu(es->s_log_block_size) >
3853             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3854                 ext4_msg(sb, KERN_ERR,
3855                          "Invalid log block size: %u",
3856                          le32_to_cpu(es->s_log_block_size));
3857                 goto failed_mount;
3858         }
3859         if (le32_to_cpu(es->s_log_cluster_size) >
3860             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3861                 ext4_msg(sb, KERN_ERR,
3862                          "Invalid log cluster size: %u",
3863                          le32_to_cpu(es->s_log_cluster_size));
3864                 goto failed_mount;
3865         }
3866
3867         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
3868                 ext4_msg(sb, KERN_ERR,
3869                          "Number of reserved GDT blocks insanely large: %d",
3870                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
3871                 goto failed_mount;
3872         }
3873
3874         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3875                 if (ext4_has_feature_inline_data(sb)) {
3876                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
3877                                         " that may contain inline data");
3878                         goto failed_mount;
3879                 }
3880                 if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
3881                         ext4_msg(sb, KERN_ERR,
3882                                 "DAX unsupported by block device.");
3883                         goto failed_mount;
3884                 }
3885         }
3886
3887         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
3888                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
3889                          es->s_encryption_level);
3890                 goto failed_mount;
3891         }
3892
3893         if (sb->s_blocksize != blocksize) {
3894                 /* Validate the filesystem blocksize */
3895                 if (!sb_set_blocksize(sb, blocksize)) {
3896                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3897                                         blocksize);
3898                         goto failed_mount;
3899                 }
3900
3901                 brelse(bh);
3902                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3903                 offset = do_div(logical_sb_block, blocksize);
3904                 bh = sb_bread_unmovable(sb, logical_sb_block);
3905                 if (!bh) {
3906                         ext4_msg(sb, KERN_ERR,
3907                                "Can't read superblock on 2nd try");
3908                         goto failed_mount;
3909                 }
3910                 es = (struct ext4_super_block *)(bh->b_data + offset);
3911                 sbi->s_es = es;
3912                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3913                         ext4_msg(sb, KERN_ERR,
3914                                "Magic mismatch, very weird!");
3915                         goto failed_mount;
3916                 }
3917         }
3918
3919         has_huge_files = ext4_has_feature_huge_file(sb);
3920         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3921                                                       has_huge_files);
3922         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3923
3924         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3925                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3926                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3927         } else {
3928                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3929                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3930                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
3931                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
3932                                  sbi->s_first_ino);
3933                         goto failed_mount;
3934                 }
3935                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3936                     (!is_power_of_2(sbi->s_inode_size)) ||
3937                     (sbi->s_inode_size > blocksize)) {
3938                         ext4_msg(sb, KERN_ERR,
3939                                "unsupported inode size: %d",
3940                                sbi->s_inode_size);
3941                         goto failed_mount;
3942                 }
3943                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3944                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3945         }
3946
3947         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3948         if (ext4_has_feature_64bit(sb)) {
3949                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3950                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3951                     !is_power_of_2(sbi->s_desc_size)) {
3952                         ext4_msg(sb, KERN_ERR,
3953                                "unsupported descriptor size %lu",
3954                                sbi->s_desc_size);
3955                         goto failed_mount;
3956                 }
3957         } else
3958                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3959
3960         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3961         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3962
3963         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3964         if (sbi->s_inodes_per_block == 0)
3965                 goto cantfind_ext4;
3966         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
3967             sbi->s_inodes_per_group > blocksize * 8) {
3968                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
3969                          sbi->s_blocks_per_group);
3970                 goto failed_mount;
3971         }
3972         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3973                                         sbi->s_inodes_per_block;
3974         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3975         sbi->s_sbh = bh;
3976         sbi->s_mount_state = le16_to_cpu(es->s_state);
3977         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3978         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3979
3980         for (i = 0; i < 4; i++)
3981                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3982         sbi->s_def_hash_version = es->s_def_hash_version;
3983         if (ext4_has_feature_dir_index(sb)) {
3984                 i = le32_to_cpu(es->s_flags);
3985                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
3986                         sbi->s_hash_unsigned = 3;
3987                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3988 #ifdef __CHAR_UNSIGNED__
3989                         if (!sb_rdonly(sb))
3990                                 es->s_flags |=
3991                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3992                         sbi->s_hash_unsigned = 3;
3993 #else
3994                         if (!sb_rdonly(sb))
3995                                 es->s_flags |=
3996                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3997 #endif
3998                 }
3999         }
4000
4001         /* Handle clustersize */
4002         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4003         has_bigalloc = ext4_has_feature_bigalloc(sb);
4004         if (has_bigalloc) {
4005                 if (clustersize < blocksize) {
4006                         ext4_msg(sb, KERN_ERR,
4007                                  "cluster size (%d) smaller than "
4008                                  "block size (%d)", clustersize, blocksize);
4009                         goto failed_mount;
4010                 }
4011                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4012                         le32_to_cpu(es->s_log_block_size);
4013                 sbi->s_clusters_per_group =
4014                         le32_to_cpu(es->s_clusters_per_group);
4015                 if (sbi->s_clusters_per_group > blocksize * 8) {
4016                         ext4_msg(sb, KERN_ERR,
4017                                  "#clusters per group too big: %lu",
4018                                  sbi->s_clusters_per_group);
4019                         goto failed_mount;
4020                 }
4021                 if (sbi->s_blocks_per_group !=
4022                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4023                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4024                                  "clusters per group (%lu) inconsistent",
4025                                  sbi->s_blocks_per_group,
4026                                  sbi->s_clusters_per_group);
4027                         goto failed_mount;
4028                 }
4029         } else {
4030                 if (clustersize != blocksize) {
4031                         ext4_msg(sb, KERN_ERR,
4032                                  "fragment/cluster size (%d) != "
4033                                  "block size (%d)", clustersize, blocksize);
4034                         goto failed_mount;
4035                 }
4036                 if (sbi->s_blocks_per_group > blocksize * 8) {
4037                         ext4_msg(sb, KERN_ERR,
4038                                  "#blocks per group too big: %lu",
4039                                  sbi->s_blocks_per_group);
4040                         goto failed_mount;
4041                 }
4042                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4043                 sbi->s_cluster_bits = 0;
4044         }
4045         sbi->s_cluster_ratio = clustersize / blocksize;
4046
4047         /* Do we have standard group size of clustersize * 8 blocks ? */
4048         if (sbi->s_blocks_per_group == clustersize << 3)
4049                 set_opt2(sb, STD_GROUP_SIZE);
4050
4051         /*
4052          * Test whether we have more sectors than will fit in sector_t,
4053          * and whether the max offset is addressable by the page cache.
4054          */
4055         err = generic_check_addressable(sb->s_blocksize_bits,
4056                                         ext4_blocks_count(es));
4057         if (err) {
4058                 ext4_msg(sb, KERN_ERR, "filesystem"
4059                          " too large to mount safely on this system");
4060                 if (sizeof(sector_t) < 8)
4061                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
4062                 goto failed_mount;
4063         }
4064
4065         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4066                 goto cantfind_ext4;
4067
4068         /* check blocks count against device size */
4069         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4070         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4071                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4072                        "exceeds size of device (%llu blocks)",
4073                        ext4_blocks_count(es), blocks_count);
4074                 goto failed_mount;
4075         }
4076
4077         /*
4078          * It makes no sense for the first data block to be beyond the end
4079          * of the filesystem.
4080          */
4081         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4082                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4083                          "block %u is beyond end of filesystem (%llu)",
4084                          le32_to_cpu(es->s_first_data_block),
4085                          ext4_blocks_count(es));
4086                 goto failed_mount;
4087         }
4088         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4089             (sbi->s_cluster_ratio == 1)) {
4090                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4091                          "block is 0 with a 1k block and cluster size");
4092                 goto failed_mount;
4093         }
4094
4095         blocks_count = (ext4_blocks_count(es) -
4096                         le32_to_cpu(es->s_first_data_block) +
4097                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4098         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4099         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4100                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
4101                        "(block count %llu, first data block %u, "
4102                        "blocks per group %lu)", sbi->s_groups_count,
4103                        ext4_blocks_count(es),
4104                        le32_to_cpu(es->s_first_data_block),
4105                        EXT4_BLOCKS_PER_GROUP(sb));
4106                 goto failed_mount;
4107         }
4108         sbi->s_groups_count = blocks_count;
4109         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4110                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4111         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4112             le32_to_cpu(es->s_inodes_count)) {
4113                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4114                          le32_to_cpu(es->s_inodes_count),
4115                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4116                 ret = -EINVAL;
4117                 goto failed_mount;
4118         }
4119         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4120                    EXT4_DESC_PER_BLOCK(sb);
4121         if (ext4_has_feature_meta_bg(sb)) {
4122                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4123                         ext4_msg(sb, KERN_WARNING,
4124                                  "first meta block group too large: %u "
4125                                  "(group descriptor block count %u)",
4126                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4127                         goto failed_mount;
4128                 }
4129         }
4130         sbi->s_group_desc = kvmalloc_array(db_count,
4131                                            sizeof(struct buffer_head *),
4132                                            GFP_KERNEL);
4133         if (sbi->s_group_desc == NULL) {
4134                 ext4_msg(sb, KERN_ERR, "not enough memory");
4135                 ret = -ENOMEM;
4136                 goto failed_mount;
4137         }
4138
4139         bgl_lock_init(sbi->s_blockgroup_lock);
4140
4141         /* Pre-read the descriptors into the buffer cache */
4142         for (i = 0; i < db_count; i++) {
4143                 block = descriptor_loc(sb, logical_sb_block, i);
4144                 sb_breadahead(sb, block);
4145         }
4146
4147         for (i = 0; i < db_count; i++) {
4148                 block = descriptor_loc(sb, logical_sb_block, i);
4149                 sbi->s_group_desc[i] = sb_bread_unmovable(sb, block);
4150                 if (!sbi->s_group_desc[i]) {
4151                         ext4_msg(sb, KERN_ERR,
4152                                "can't read group descriptor %d", i);
4153                         db_count = i;
4154                         goto failed_mount2;
4155                 }
4156         }
4157         sbi->s_gdb_count = db_count;
4158         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4159                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4160                 ret = -EFSCORRUPTED;
4161                 goto failed_mount2;
4162         }
4163
4164         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4165
4166         /* Register extent status tree shrinker */
4167         if (ext4_es_register_shrinker(sbi))
4168                 goto failed_mount3;
4169
4170         sbi->s_stripe = ext4_get_stripe_size(sbi);
4171         sbi->s_extent_max_zeroout_kb = 32;
4172
4173         /*
4174          * set up enough so that it can read an inode
4175          */
4176         sb->s_op = &ext4_sops;
4177         sb->s_export_op = &ext4_export_ops;
4178         sb->s_xattr = ext4_xattr_handlers;
4179 #ifdef CONFIG_FS_ENCRYPTION
4180         sb->s_cop = &ext4_cryptops;
4181 #endif
4182 #ifdef CONFIG_QUOTA
4183         sb->dq_op = &ext4_quota_operations;
4184         if (ext4_has_feature_quota(sb))
4185                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4186         else
4187                 sb->s_qcop = &ext4_qctl_operations;
4188         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4189 #endif
4190         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4191
4192         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4193         mutex_init(&sbi->s_orphan_lock);
4194
4195         sb->s_root = NULL;
4196
4197         needs_recovery = (es->s_last_orphan != 0 ||
4198                           ext4_has_feature_journal_needs_recovery(sb));
4199
4200         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4201                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4202                         goto failed_mount3a;
4203
4204         /*
4205          * The first inode we look at is the journal inode.  Don't try
4206          * root first: it may be modified in the journal!
4207          */
4208         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4209                 err = ext4_load_journal(sb, es, journal_devnum);
4210                 if (err)
4211                         goto failed_mount3a;
4212         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4213                    ext4_has_feature_journal_needs_recovery(sb)) {
4214                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4215                        "suppressed and not mounted read-only");
4216                 goto failed_mount_wq;
4217         } else {
4218                 /* Nojournal mode, all journal mount options are illegal */
4219                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4220                         ext4_msg(sb, KERN_ERR, "can't mount with "
4221                                  "journal_checksum, fs mounted w/o journal");
4222                         goto failed_mount_wq;
4223                 }
4224                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4225                         ext4_msg(sb, KERN_ERR, "can't mount with "
4226                                  "journal_async_commit, fs mounted w/o journal");
4227                         goto failed_mount_wq;
4228                 }
4229                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4230                         ext4_msg(sb, KERN_ERR, "can't mount with "
4231                                  "commit=%lu, fs mounted w/o journal",
4232                                  sbi->s_commit_interval / HZ);
4233                         goto failed_mount_wq;
4234                 }
4235                 if (EXT4_MOUNT_DATA_FLAGS &
4236                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4237                         ext4_msg(sb, KERN_ERR, "can't mount with "
4238                                  "data=, fs mounted w/o journal");
4239                         goto failed_mount_wq;
4240                 }
4241                 sbi->s_def_mount_opt &= EXT4_MOUNT_JOURNAL_CHECKSUM;
4242                 clear_opt(sb, JOURNAL_CHECKSUM);
4243                 clear_opt(sb, DATA_FLAGS);
4244                 sbi->s_journal = NULL;
4245                 needs_recovery = 0;
4246                 goto no_journal;
4247         }
4248
4249         if (ext4_has_feature_64bit(sb) &&
4250             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4251                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4252                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4253                 goto failed_mount_wq;
4254         }
4255
4256         if (!set_journal_csum_feature_set(sb)) {
4257                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4258                          "feature set");
4259                 goto failed_mount_wq;
4260         }
4261
4262         /* We have now updated the journal if required, so we can
4263          * validate the data journaling mode. */
4264         switch (test_opt(sb, DATA_FLAGS)) {
4265         case 0:
4266                 /* No mode set, assume a default based on the journal
4267                  * capabilities: ORDERED_DATA if the journal can
4268                  * cope, else JOURNAL_DATA
4269                  */
4270                 if (jbd2_journal_check_available_features
4271                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4272                         set_opt(sb, ORDERED_DATA);
4273                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4274                 } else {
4275                         set_opt(sb, JOURNAL_DATA);
4276                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4277                 }
4278                 break;
4279
4280         case EXT4_MOUNT_ORDERED_DATA:
4281         case EXT4_MOUNT_WRITEBACK_DATA:
4282                 if (!jbd2_journal_check_available_features
4283                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4284                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4285                                "requested data journaling mode");
4286                         goto failed_mount_wq;
4287                 }
4288         default:
4289                 break;
4290         }
4291
4292         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4293             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4294                 ext4_msg(sb, KERN_ERR, "can't mount with "
4295                         "journal_async_commit in data=ordered mode");
4296                 goto failed_mount_wq;
4297         }
4298
4299         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4300
4301         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4302
4303 no_journal:
4304         if (!test_opt(sb, NO_MBCACHE)) {
4305                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4306                 if (!sbi->s_ea_block_cache) {
4307                         ext4_msg(sb, KERN_ERR,
4308                                  "Failed to create ea_block_cache");
4309                         goto failed_mount_wq;
4310                 }
4311
4312                 if (ext4_has_feature_ea_inode(sb)) {
4313                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4314                         if (!sbi->s_ea_inode_cache) {
4315                                 ext4_msg(sb, KERN_ERR,
4316                                          "Failed to create ea_inode_cache");
4317                                 goto failed_mount_wq;
4318                         }
4319                 }
4320         }
4321
4322         if ((DUMMY_ENCRYPTION_ENABLED(sbi) || ext4_has_feature_encrypt(sb)) &&
4323             (blocksize != PAGE_SIZE)) {
4324                 ext4_msg(sb, KERN_ERR,
4325                          "Unsupported blocksize for fs encryption");
4326                 goto failed_mount_wq;
4327         }
4328
4329         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4330             !ext4_has_feature_encrypt(sb)) {
4331                 ext4_set_feature_encrypt(sb);
4332                 ext4_commit_super(sb, 1);
4333         }
4334
4335         /*
4336          * Get the # of file system overhead blocks from the
4337          * superblock if present.
4338          */
4339         if (es->s_overhead_clusters)
4340                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4341         else {
4342                 err = ext4_calculate_overhead(sb);
4343                 if (err)
4344                         goto failed_mount_wq;
4345         }
4346
4347         /*
4348          * The maximum number of concurrent works can be high and
4349          * concurrency isn't really necessary.  Limit it to 1.
4350          */
4351         EXT4_SB(sb)->rsv_conversion_wq =
4352                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4353         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4354                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4355                 ret = -ENOMEM;
4356                 goto failed_mount4;
4357         }
4358
4359         /*
4360          * The jbd2_journal_load will have done any necessary log recovery,
4361          * so we can safely mount the rest of the filesystem now.
4362          */
4363
4364         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4365         if (IS_ERR(root)) {
4366                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4367                 ret = PTR_ERR(root);
4368                 root = NULL;
4369                 goto failed_mount4;
4370         }
4371         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4372                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4373                 iput(root);
4374                 goto failed_mount4;
4375         }
4376         sb->s_root = d_make_root(root);
4377         if (!sb->s_root) {
4378                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4379                 ret = -ENOMEM;
4380                 goto failed_mount4;
4381         }
4382
4383         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4384         if (ret == -EROFS) {
4385                 sb->s_flags |= SB_RDONLY;
4386                 ret = 0;
4387         } else if (ret)
4388                 goto failed_mount4a;
4389
4390         /* determine the minimum size of new large inodes, if present */
4391         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE &&
4392             sbi->s_want_extra_isize == 0) {
4393                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4394                                                      EXT4_GOOD_OLD_INODE_SIZE;
4395                 if (ext4_has_feature_extra_isize(sb)) {
4396                         if (sbi->s_want_extra_isize <
4397                             le16_to_cpu(es->s_want_extra_isize))
4398                                 sbi->s_want_extra_isize =
4399                                         le16_to_cpu(es->s_want_extra_isize);
4400                         if (sbi->s_want_extra_isize <
4401                             le16_to_cpu(es->s_min_extra_isize))
4402                                 sbi->s_want_extra_isize =
4403                                         le16_to_cpu(es->s_min_extra_isize);
4404                 }
4405         }
4406         /* Check if enough inode space is available */
4407         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
4408                                                         sbi->s_inode_size) {
4409                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4410                                                        EXT4_GOOD_OLD_INODE_SIZE;
4411                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
4412                          "available");
4413         }
4414
4415         ext4_set_resv_clusters(sb);
4416
4417         err = ext4_setup_system_zone(sb);
4418         if (err) {
4419                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4420                          "zone (%d)", err);
4421                 goto failed_mount4a;
4422         }
4423
4424         ext4_ext_init(sb);
4425         err = ext4_mb_init(sb);
4426         if (err) {
4427                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4428                          err);
4429                 goto failed_mount5;
4430         }
4431
4432         block = ext4_count_free_clusters(sb);
4433         ext4_free_blocks_count_set(sbi->s_es,
4434                                    EXT4_C2B(sbi, block));
4435         ext4_superblock_csum_set(sb);
4436         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4437                                   GFP_KERNEL);
4438         if (!err) {
4439                 unsigned long freei = ext4_count_free_inodes(sb);
4440                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4441                 ext4_superblock_csum_set(sb);
4442                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4443                                           GFP_KERNEL);
4444         }
4445         if (!err)
4446                 err = percpu_counter_init(&sbi->s_dirs_counter,
4447                                           ext4_count_dirs(sb), GFP_KERNEL);
4448         if (!err)
4449                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4450                                           GFP_KERNEL);
4451         if (!err)
4452                 err = percpu_init_rwsem(&sbi->s_journal_flag_rwsem);
4453
4454         if (err) {
4455                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4456                 goto failed_mount6;
4457         }
4458
4459         if (ext4_has_feature_flex_bg(sb))
4460                 if (!ext4_fill_flex_info(sb)) {
4461                         ext4_msg(sb, KERN_ERR,
4462                                "unable to initialize "
4463                                "flex_bg meta info!");
4464                         goto failed_mount6;
4465                 }
4466
4467         err = ext4_register_li_request(sb, first_not_zeroed);
4468         if (err)
4469                 goto failed_mount6;
4470
4471         err = ext4_register_sysfs(sb);
4472         if (err)
4473                 goto failed_mount7;
4474
4475 #ifdef CONFIG_QUOTA
4476         /* Enable quota usage during mount. */
4477         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4478                 err = ext4_enable_quotas(sb);
4479                 if (err)
4480                         goto failed_mount8;
4481         }
4482 #endif  /* CONFIG_QUOTA */
4483
4484         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4485         ext4_orphan_cleanup(sb, es);
4486         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4487         if (needs_recovery) {
4488                 ext4_msg(sb, KERN_INFO, "recovery complete");
4489                 ext4_mark_recovery_complete(sb, es);
4490         }
4491         if (EXT4_SB(sb)->s_journal) {
4492                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4493                         descr = " journalled data mode";
4494                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4495                         descr = " ordered data mode";
4496                 else
4497                         descr = " writeback data mode";
4498         } else
4499                 descr = "out journal";
4500
4501         if (test_opt(sb, DISCARD)) {
4502                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4503                 if (!blk_queue_discard(q))
4504                         ext4_msg(sb, KERN_WARNING,
4505                                  "mounting with \"discard\" option, but "
4506                                  "the device does not support discard");
4507         }
4508
4509         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4510                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4511                          "Opts: %.*s%s%s", descr,
4512                          (int) sizeof(sbi->s_es->s_mount_opts),
4513                          sbi->s_es->s_mount_opts,
4514                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4515
4516         if (es->s_error_count)
4517                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4518
4519         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4520         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4521         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4522         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4523
4524         kfree(orig_data);
4525         return 0;
4526
4527 cantfind_ext4:
4528         if (!silent)
4529                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4530         goto failed_mount;
4531
4532 #ifdef CONFIG_QUOTA
4533 failed_mount8:
4534         ext4_unregister_sysfs(sb);
4535 #endif
4536 failed_mount7:
4537         ext4_unregister_li_request(sb);
4538 failed_mount6:
4539         ext4_mb_release(sb);
4540         if (sbi->s_flex_groups)
4541                 kvfree(sbi->s_flex_groups);
4542         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4543         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4544         percpu_counter_destroy(&sbi->s_dirs_counter);
4545         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4546         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
4547 failed_mount5:
4548         ext4_ext_release(sb);
4549         ext4_release_system_zone(sb);
4550 failed_mount4a:
4551         dput(sb->s_root);
4552         sb->s_root = NULL;
4553 failed_mount4:
4554         ext4_msg(sb, KERN_ERR, "mount failed");
4555         if (EXT4_SB(sb)->rsv_conversion_wq)
4556                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4557 failed_mount_wq:
4558         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4559         sbi->s_ea_inode_cache = NULL;
4560
4561         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4562         sbi->s_ea_block_cache = NULL;
4563
4564         if (sbi->s_journal) {
4565                 jbd2_journal_destroy(sbi->s_journal);
4566                 sbi->s_journal = NULL;
4567         }
4568 failed_mount3a:
4569         ext4_es_unregister_shrinker(sbi);
4570 failed_mount3:
4571         del_timer_sync(&sbi->s_err_report);
4572         if (sbi->s_mmp_tsk)
4573                 kthread_stop(sbi->s_mmp_tsk);
4574 failed_mount2:
4575         for (i = 0; i < db_count; i++)
4576                 brelse(sbi->s_group_desc[i]);
4577         kvfree(sbi->s_group_desc);
4578 failed_mount:
4579         if (sbi->s_chksum_driver)
4580                 crypto_free_shash(sbi->s_chksum_driver);
4581 #ifdef CONFIG_QUOTA
4582         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4583                 kfree(sbi->s_qf_names[i]);
4584 #endif
4585         ext4_blkdev_remove(sbi);
4586         brelse(bh);
4587 out_fail:
4588         sb->s_fs_info = NULL;
4589         kfree(sbi->s_blockgroup_lock);
4590 out_free_base:
4591         kfree(sbi);
4592         kfree(orig_data);
4593         fs_put_dax(dax_dev);
4594         return err ? err : ret;
4595 }
4596
4597 /*
4598  * Setup any per-fs journal parameters now.  We'll do this both on
4599  * initial mount, once the journal has been initialised but before we've
4600  * done any recovery; and again on any subsequent remount.
4601  */
4602 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4603 {
4604         struct ext4_sb_info *sbi = EXT4_SB(sb);
4605
4606         journal->j_commit_interval = sbi->s_commit_interval;
4607         journal->j_min_batch_time = sbi->s_min_batch_time;
4608         journal->j_max_batch_time = sbi->s_max_batch_time;
4609
4610         write_lock(&journal->j_state_lock);
4611         if (test_opt(sb, BARRIER))
4612                 journal->j_flags |= JBD2_BARRIER;
4613         else
4614                 journal->j_flags &= ~JBD2_BARRIER;
4615         if (test_opt(sb, DATA_ERR_ABORT))
4616                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4617         else
4618                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4619         write_unlock(&journal->j_state_lock);
4620 }
4621
4622 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4623                                              unsigned int journal_inum)
4624 {
4625         struct inode *journal_inode;
4626
4627         /*
4628          * Test for the existence of a valid inode on disk.  Bad things
4629          * happen if we iget() an unused inode, as the subsequent iput()
4630          * will try to delete it.
4631          */
4632         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
4633         if (IS_ERR(journal_inode)) {
4634                 ext4_msg(sb, KERN_ERR, "no journal found");
4635                 return NULL;
4636         }
4637         if (!journal_inode->i_nlink) {
4638                 make_bad_inode(journal_inode);
4639                 iput(journal_inode);
4640                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4641                 return NULL;
4642         }
4643
4644         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4645                   journal_inode, journal_inode->i_size);
4646         if (!S_ISREG(journal_inode->i_mode)) {
4647                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4648                 iput(journal_inode);
4649                 return NULL;
4650         }
4651         return journal_inode;
4652 }
4653
4654 static journal_t *ext4_get_journal(struct super_block *sb,
4655                                    unsigned int journal_inum)
4656 {
4657         struct inode *journal_inode;
4658         journal_t *journal;
4659
4660         BUG_ON(!ext4_has_feature_journal(sb));
4661
4662         journal_inode = ext4_get_journal_inode(sb, journal_inum);
4663         if (!journal_inode)
4664                 return NULL;
4665
4666         journal = jbd2_journal_init_inode(journal_inode);
4667         if (!journal) {
4668                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4669                 iput(journal_inode);
4670                 return NULL;
4671         }
4672         journal->j_private = sb;
4673         ext4_init_journal_params(sb, journal);
4674         return journal;
4675 }
4676
4677 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4678                                        dev_t j_dev)
4679 {
4680         struct buffer_head *bh;
4681         journal_t *journal;
4682         ext4_fsblk_t start;
4683         ext4_fsblk_t len;
4684         int hblock, blocksize;
4685         ext4_fsblk_t sb_block;
4686         unsigned long offset;
4687         struct ext4_super_block *es;
4688         struct block_device *bdev;
4689
4690         BUG_ON(!ext4_has_feature_journal(sb));
4691
4692         bdev = ext4_blkdev_get(j_dev, sb);
4693         if (bdev == NULL)
4694                 return NULL;
4695
4696         blocksize = sb->s_blocksize;
4697         hblock = bdev_logical_block_size(bdev);
4698         if (blocksize < hblock) {
4699                 ext4_msg(sb, KERN_ERR,
4700                         "blocksize too small for journal device");
4701                 goto out_bdev;
4702         }
4703
4704         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4705         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4706         set_blocksize(bdev, blocksize);
4707         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4708                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4709                        "external journal");
4710                 goto out_bdev;
4711         }
4712
4713         es = (struct ext4_super_block *) (bh->b_data + offset);
4714         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4715             !(le32_to_cpu(es->s_feature_incompat) &
4716               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4717                 ext4_msg(sb, KERN_ERR, "external journal has "
4718                                         "bad superblock");
4719                 brelse(bh);
4720                 goto out_bdev;
4721         }
4722
4723         if ((le32_to_cpu(es->s_feature_ro_compat) &
4724              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4725             es->s_checksum != ext4_superblock_csum(sb, es)) {
4726                 ext4_msg(sb, KERN_ERR, "external journal has "
4727                                        "corrupt superblock");
4728                 brelse(bh);
4729                 goto out_bdev;
4730         }
4731
4732         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4733                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4734                 brelse(bh);
4735                 goto out_bdev;
4736         }
4737
4738         len = ext4_blocks_count(es);
4739         start = sb_block + 1;
4740         brelse(bh);     /* we're done with the superblock */
4741
4742         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4743                                         start, len, blocksize);
4744         if (!journal) {
4745                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4746                 goto out_bdev;
4747         }
4748         journal->j_private = sb;
4749         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4750         wait_on_buffer(journal->j_sb_buffer);
4751         if (!buffer_uptodate(journal->j_sb_buffer)) {
4752                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4753                 goto out_journal;
4754         }
4755         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4756                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4757                                         "user (unsupported) - %d",
4758                         be32_to_cpu(journal->j_superblock->s_nr_users));
4759                 goto out_journal;
4760         }
4761         EXT4_SB(sb)->journal_bdev = bdev;
4762         ext4_init_journal_params(sb, journal);
4763         return journal;
4764
4765 out_journal:
4766         jbd2_journal_destroy(journal);
4767 out_bdev:
4768         ext4_blkdev_put(bdev);
4769         return NULL;
4770 }
4771
4772 static int ext4_load_journal(struct super_block *sb,
4773                              struct ext4_super_block *es,
4774                              unsigned long journal_devnum)
4775 {
4776         journal_t *journal;
4777         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4778         dev_t journal_dev;
4779         int err = 0;
4780         int really_read_only;
4781
4782         BUG_ON(!ext4_has_feature_journal(sb));
4783
4784         if (journal_devnum &&
4785             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4786                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4787                         "numbers have changed");
4788                 journal_dev = new_decode_dev(journal_devnum);
4789         } else
4790                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4791
4792         really_read_only = bdev_read_only(sb->s_bdev);
4793
4794         /*
4795          * Are we loading a blank journal or performing recovery after a
4796          * crash?  For recovery, we need to check in advance whether we
4797          * can get read-write access to the device.
4798          */
4799         if (ext4_has_feature_journal_needs_recovery(sb)) {
4800                 if (sb_rdonly(sb)) {
4801                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4802                                         "required on readonly filesystem");
4803                         if (really_read_only) {
4804                                 ext4_msg(sb, KERN_ERR, "write access "
4805                                         "unavailable, cannot proceed "
4806                                         "(try mounting with noload)");
4807                                 return -EROFS;
4808                         }
4809                         ext4_msg(sb, KERN_INFO, "write access will "
4810                                "be enabled during recovery");
4811                 }
4812         }
4813
4814         if (journal_inum && journal_dev) {
4815                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4816                        "and inode journals!");
4817                 return -EINVAL;
4818         }
4819
4820         if (journal_inum) {
4821                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4822                         return -EINVAL;
4823         } else {
4824                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4825                         return -EINVAL;
4826         }
4827
4828         if (!(journal->j_flags & JBD2_BARRIER))
4829                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4830
4831         if (!ext4_has_feature_journal_needs_recovery(sb))
4832                 err = jbd2_journal_wipe(journal, !really_read_only);
4833         if (!err) {
4834                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4835                 if (save)
4836                         memcpy(save, ((char *) es) +
4837                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4838                 err = jbd2_journal_load(journal);
4839                 if (save)
4840                         memcpy(((char *) es) + EXT4_S_ERR_START,
4841                                save, EXT4_S_ERR_LEN);
4842                 kfree(save);
4843         }
4844
4845         if (err) {
4846                 ext4_msg(sb, KERN_ERR, "error loading journal");
4847                 jbd2_journal_destroy(journal);
4848                 return err;
4849         }
4850
4851         EXT4_SB(sb)->s_journal = journal;
4852         ext4_clear_journal_err(sb, es);
4853
4854         if (!really_read_only && journal_devnum &&
4855             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4856                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4857
4858                 /* Make sure we flush the recovery flag to disk. */
4859                 ext4_commit_super(sb, 1);
4860         }
4861
4862         return 0;
4863 }
4864
4865 static int ext4_commit_super(struct super_block *sb, int sync)
4866 {
4867         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4868         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4869         int error = 0;
4870
4871         if (!sbh || block_device_ejected(sb))
4872                 return error;
4873
4874         /*
4875          * The superblock bh should be mapped, but it might not be if the
4876          * device was hot-removed. Not much we can do but fail the I/O.
4877          */
4878         if (!buffer_mapped(sbh))
4879                 return error;
4880
4881         /*
4882          * If the file system is mounted read-only, don't update the
4883          * superblock write time.  This avoids updating the superblock
4884          * write time when we are mounting the root file system
4885          * read/only but we need to replay the journal; at that point,
4886          * for people who are east of GMT and who make their clock
4887          * tick in localtime for Windows bug-for-bug compatibility,
4888          * the clock is set in the future, and this will cause e2fsck
4889          * to complain and force a full file system check.
4890          */
4891         if (!(sb->s_flags & SB_RDONLY))
4892                 ext4_update_tstamp(es, s_wtime);
4893         if (sb->s_bdev->bd_part)
4894                 es->s_kbytes_written =
4895                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4896                             ((part_stat_read(sb->s_bdev->bd_part,
4897                                              sectors[STAT_WRITE]) -
4898                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4899         else
4900                 es->s_kbytes_written =
4901                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4902         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
4903                 ext4_free_blocks_count_set(es,
4904                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4905                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4906         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
4907                 es->s_free_inodes_count =
4908                         cpu_to_le32(percpu_counter_sum_positive(
4909                                 &EXT4_SB(sb)->s_freeinodes_counter));
4910         BUFFER_TRACE(sbh, "marking dirty");
4911         ext4_superblock_csum_set(sb);
4912         if (sync)
4913                 lock_buffer(sbh);
4914         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
4915                 /*
4916                  * Oh, dear.  A previous attempt to write the
4917                  * superblock failed.  This could happen because the
4918                  * USB device was yanked out.  Or it could happen to
4919                  * be a transient write error and maybe the block will
4920                  * be remapped.  Nothing we can do but to retry the
4921                  * write and hope for the best.
4922                  */
4923                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4924                        "superblock detected");
4925                 clear_buffer_write_io_error(sbh);
4926                 set_buffer_uptodate(sbh);
4927         }
4928         mark_buffer_dirty(sbh);
4929         if (sync) {
4930                 unlock_buffer(sbh);
4931                 error = __sync_dirty_buffer(sbh,
4932                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
4933                 if (buffer_write_io_error(sbh)) {
4934                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4935                                "superblock");
4936                         clear_buffer_write_io_error(sbh);
4937                         set_buffer_uptodate(sbh);
4938                 }
4939         }
4940         return error;
4941 }
4942
4943 /*
4944  * Have we just finished recovery?  If so, and if we are mounting (or
4945  * remounting) the filesystem readonly, then we will end up with a
4946  * consistent fs on disk.  Record that fact.
4947  */
4948 static void ext4_mark_recovery_complete(struct super_block *sb,
4949                                         struct ext4_super_block *es)
4950 {
4951         journal_t *journal = EXT4_SB(sb)->s_journal;
4952
4953         if (!ext4_has_feature_journal(sb)) {
4954                 BUG_ON(journal != NULL);
4955                 return;
4956         }
4957         jbd2_journal_lock_updates(journal);
4958         if (jbd2_journal_flush(journal) < 0)
4959                 goto out;
4960
4961         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
4962                 ext4_clear_feature_journal_needs_recovery(sb);
4963                 ext4_commit_super(sb, 1);
4964         }
4965
4966 out:
4967         jbd2_journal_unlock_updates(journal);
4968 }
4969
4970 /*
4971  * If we are mounting (or read-write remounting) a filesystem whose journal
4972  * has recorded an error from a previous lifetime, move that error to the
4973  * main filesystem now.
4974  */
4975 static void ext4_clear_journal_err(struct super_block *sb,
4976                                    struct ext4_super_block *es)
4977 {
4978         journal_t *journal;
4979         int j_errno;
4980         const char *errstr;
4981
4982         BUG_ON(!ext4_has_feature_journal(sb));
4983
4984         journal = EXT4_SB(sb)->s_journal;
4985
4986         /*
4987          * Now check for any error status which may have been recorded in the
4988          * journal by a prior ext4_error() or ext4_abort()
4989          */
4990
4991         j_errno = jbd2_journal_errno(journal);
4992         if (j_errno) {
4993                 char nbuf[16];
4994
4995                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4996                 ext4_warning(sb, "Filesystem error recorded "
4997                              "from previous mount: %s", errstr);
4998                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4999
5000                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5001                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5002                 ext4_commit_super(sb, 1);
5003
5004                 jbd2_journal_clear_err(journal);
5005                 jbd2_journal_update_sb_errno(journal);
5006         }
5007 }
5008
5009 /*
5010  * Force the running and committing transactions to commit,
5011  * and wait on the commit.
5012  */
5013 int ext4_force_commit(struct super_block *sb)
5014 {
5015         journal_t *journal;
5016
5017         if (sb_rdonly(sb))
5018                 return 0;
5019
5020         journal = EXT4_SB(sb)->s_journal;
5021         return ext4_journal_force_commit(journal);
5022 }
5023
5024 static int ext4_sync_fs(struct super_block *sb, int wait)
5025 {
5026         int ret = 0;
5027         tid_t target;
5028         bool needs_barrier = false;
5029         struct ext4_sb_info *sbi = EXT4_SB(sb);
5030
5031         if (unlikely(ext4_forced_shutdown(sbi)))
5032                 return 0;
5033
5034         trace_ext4_sync_fs(sb, wait);
5035         flush_workqueue(sbi->rsv_conversion_wq);
5036         /*
5037          * Writeback quota in non-journalled quota case - journalled quota has
5038          * no dirty dquots
5039          */
5040         dquot_writeback_dquots(sb, -1);
5041         /*
5042          * Data writeback is possible w/o journal transaction, so barrier must
5043          * being sent at the end of the function. But we can skip it if
5044          * transaction_commit will do it for us.
5045          */
5046         if (sbi->s_journal) {
5047                 target = jbd2_get_latest_transaction(sbi->s_journal);
5048                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5049                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5050                         needs_barrier = true;
5051
5052                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5053                         if (wait)
5054                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5055                                                            target);
5056                 }
5057         } else if (wait && test_opt(sb, BARRIER))
5058                 needs_barrier = true;
5059         if (needs_barrier) {
5060                 int err;
5061                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
5062                 if (!ret)
5063                         ret = err;
5064         }
5065
5066         return ret;
5067 }
5068
5069 /*
5070  * LVM calls this function before a (read-only) snapshot is created.  This
5071  * gives us a chance to flush the journal completely and mark the fs clean.
5072  *
5073  * Note that only this function cannot bring a filesystem to be in a clean
5074  * state independently. It relies on upper layer to stop all data & metadata
5075  * modifications.
5076  */
5077 static int ext4_freeze(struct super_block *sb)
5078 {
5079         int error = 0;
5080         journal_t *journal;
5081
5082         if (sb_rdonly(sb))
5083                 return 0;
5084
5085         journal = EXT4_SB(sb)->s_journal;
5086
5087         if (journal) {
5088                 /* Now we set up the journal barrier. */
5089                 jbd2_journal_lock_updates(journal);
5090
5091                 /*
5092                  * Don't clear the needs_recovery flag if we failed to
5093                  * flush the journal.
5094                  */
5095                 error = jbd2_journal_flush(journal);
5096                 if (error < 0)
5097                         goto out;
5098
5099                 /* Journal blocked and flushed, clear needs_recovery flag. */
5100                 ext4_clear_feature_journal_needs_recovery(sb);
5101         }
5102
5103         error = ext4_commit_super(sb, 1);
5104 out:
5105         if (journal)
5106                 /* we rely on upper layer to stop further updates */
5107                 jbd2_journal_unlock_updates(journal);
5108         return error;
5109 }
5110
5111 /*
5112  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5113  * flag here, even though the filesystem is not technically dirty yet.
5114  */
5115 static int ext4_unfreeze(struct super_block *sb)
5116 {
5117         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5118                 return 0;
5119
5120         if (EXT4_SB(sb)->s_journal) {
5121                 /* Reset the needs_recovery flag before the fs is unlocked. */
5122                 ext4_set_feature_journal_needs_recovery(sb);
5123         }
5124
5125         ext4_commit_super(sb, 1);
5126         return 0;
5127 }
5128
5129 /*
5130  * Structure to save mount options for ext4_remount's benefit
5131  */
5132 struct ext4_mount_options {
5133         unsigned long s_mount_opt;
5134         unsigned long s_mount_opt2;
5135         kuid_t s_resuid;
5136         kgid_t s_resgid;
5137         unsigned long s_commit_interval;
5138         u32 s_min_batch_time, s_max_batch_time;
5139 #ifdef CONFIG_QUOTA
5140         int s_jquota_fmt;
5141         char *s_qf_names[EXT4_MAXQUOTAS];
5142 #endif
5143 };
5144
5145 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5146 {
5147         struct ext4_super_block *es;
5148         struct ext4_sb_info *sbi = EXT4_SB(sb);
5149         unsigned long old_sb_flags;
5150         struct ext4_mount_options old_opts;
5151         int enable_quota = 0;
5152         ext4_group_t g;
5153         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5154         int err = 0;
5155 #ifdef CONFIG_QUOTA
5156         int i, j;
5157         char *to_free[EXT4_MAXQUOTAS];
5158 #endif
5159         char *orig_data = kstrdup(data, GFP_KERNEL);
5160
5161         if (data && !orig_data)
5162                 return -ENOMEM;
5163
5164         /* Store the original options */
5165         old_sb_flags = sb->s_flags;
5166         old_opts.s_mount_opt = sbi->s_mount_opt;
5167         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5168         old_opts.s_resuid = sbi->s_resuid;
5169         old_opts.s_resgid = sbi->s_resgid;
5170         old_opts.s_commit_interval = sbi->s_commit_interval;
5171         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5172         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5173 #ifdef CONFIG_QUOTA
5174         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5175         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5176                 if (sbi->s_qf_names[i]) {
5177                         char *qf_name = get_qf_name(sb, sbi, i);
5178
5179                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5180                         if (!old_opts.s_qf_names[i]) {
5181                                 for (j = 0; j < i; j++)
5182                                         kfree(old_opts.s_qf_names[j]);
5183                                 kfree(orig_data);
5184                                 return -ENOMEM;
5185                         }
5186                 } else
5187                         old_opts.s_qf_names[i] = NULL;
5188 #endif
5189         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5190                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5191
5192         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5193                 err = -EINVAL;
5194                 goto restore_opts;
5195         }
5196
5197         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5198             test_opt(sb, JOURNAL_CHECKSUM)) {
5199                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5200                          "during remount not supported; ignoring");
5201                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5202         }
5203
5204         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5205                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5206                         ext4_msg(sb, KERN_ERR, "can't mount with "
5207                                  "both data=journal and delalloc");
5208                         err = -EINVAL;
5209                         goto restore_opts;
5210                 }
5211                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5212                         ext4_msg(sb, KERN_ERR, "can't mount with "
5213                                  "both data=journal and dioread_nolock");
5214                         err = -EINVAL;
5215                         goto restore_opts;
5216                 }
5217                 if (test_opt(sb, DAX)) {
5218                         ext4_msg(sb, KERN_ERR, "can't mount with "
5219                                  "both data=journal and dax");
5220                         err = -EINVAL;
5221                         goto restore_opts;
5222                 }
5223         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5224                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5225                         ext4_msg(sb, KERN_ERR, "can't mount with "
5226                                 "journal_async_commit in data=ordered mode");
5227                         err = -EINVAL;
5228                         goto restore_opts;
5229                 }
5230         }
5231
5232         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5233                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5234                 err = -EINVAL;
5235                 goto restore_opts;
5236         }
5237
5238         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
5239                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
5240                         "dax flag with busy inodes while remounting");
5241                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
5242         }
5243
5244         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5245                 ext4_abort(sb, "Abort forced by user");
5246
5247         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5248                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5249
5250         es = sbi->s_es;
5251
5252         if (sbi->s_journal) {
5253                 ext4_init_journal_params(sb, sbi->s_journal);
5254                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5255         }
5256
5257         if (*flags & SB_LAZYTIME)
5258                 sb->s_flags |= SB_LAZYTIME;
5259
5260         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5261                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5262                         err = -EROFS;
5263                         goto restore_opts;
5264                 }
5265
5266                 if (*flags & SB_RDONLY) {
5267                         err = sync_filesystem(sb);
5268                         if (err < 0)
5269                                 goto restore_opts;
5270                         err = dquot_suspend(sb, -1);
5271                         if (err < 0)
5272                                 goto restore_opts;
5273
5274                         /*
5275                          * First of all, the unconditional stuff we have to do
5276                          * to disable replay of the journal when we next remount
5277                          */
5278                         sb->s_flags |= SB_RDONLY;
5279
5280                         /*
5281                          * OK, test if we are remounting a valid rw partition
5282                          * readonly, and if so set the rdonly flag and then
5283                          * mark the partition as valid again.
5284                          */
5285                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5286                             (sbi->s_mount_state & EXT4_VALID_FS))
5287                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5288
5289                         if (sbi->s_journal)
5290                                 ext4_mark_recovery_complete(sb, es);
5291                         if (sbi->s_mmp_tsk)
5292                                 kthread_stop(sbi->s_mmp_tsk);
5293                 } else {
5294                         /* Make sure we can mount this feature set readwrite */
5295                         if (ext4_has_feature_readonly(sb) ||
5296                             !ext4_feature_set_ok(sb, 0)) {
5297                                 err = -EROFS;
5298                                 goto restore_opts;
5299                         }
5300                         /*
5301                          * Make sure the group descriptor checksums
5302                          * are sane.  If they aren't, refuse to remount r/w.
5303                          */
5304                         for (g = 0; g < sbi->s_groups_count; g++) {
5305                                 struct ext4_group_desc *gdp =
5306                                         ext4_get_group_desc(sb, g, NULL);
5307
5308                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5309                                         ext4_msg(sb, KERN_ERR,
5310                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5311                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5312                                                le16_to_cpu(gdp->bg_checksum));
5313                                         err = -EFSBADCRC;
5314                                         goto restore_opts;
5315                                 }
5316                         }
5317
5318                         /*
5319                          * If we have an unprocessed orphan list hanging
5320                          * around from a previously readonly bdev mount,
5321                          * require a full umount/remount for now.
5322                          */
5323                         if (es->s_last_orphan) {
5324                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5325                                        "remount RDWR because of unprocessed "
5326                                        "orphan inode list.  Please "
5327                                        "umount/remount instead");
5328                                 err = -EINVAL;
5329                                 goto restore_opts;
5330                         }
5331
5332                         /*
5333                          * Mounting a RDONLY partition read-write, so reread
5334                          * and store the current valid flag.  (It may have
5335                          * been changed by e2fsck since we originally mounted
5336                          * the partition.)
5337                          */
5338                         if (sbi->s_journal)
5339                                 ext4_clear_journal_err(sb, es);
5340                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5341
5342                         err = ext4_setup_super(sb, es, 0);
5343                         if (err)
5344                                 goto restore_opts;
5345
5346                         sb->s_flags &= ~SB_RDONLY;
5347                         if (ext4_has_feature_mmp(sb))
5348                                 if (ext4_multi_mount_protect(sb,
5349                                                 le64_to_cpu(es->s_mmp_block))) {
5350                                         err = -EROFS;
5351                                         goto restore_opts;
5352                                 }
5353                         enable_quota = 1;
5354                 }
5355         }
5356
5357         /*
5358          * Reinitialize lazy itable initialization thread based on
5359          * current settings
5360          */
5361         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5362                 ext4_unregister_li_request(sb);
5363         else {
5364                 ext4_group_t first_not_zeroed;
5365                 first_not_zeroed = ext4_has_uninit_itable(sb);
5366                 ext4_register_li_request(sb, first_not_zeroed);
5367         }
5368
5369         ext4_setup_system_zone(sb);
5370         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5371                 err = ext4_commit_super(sb, 1);
5372                 if (err)
5373                         goto restore_opts;
5374         }
5375
5376 #ifdef CONFIG_QUOTA
5377         /* Release old quota file names */
5378         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5379                 kfree(old_opts.s_qf_names[i]);
5380         if (enable_quota) {
5381                 if (sb_any_quota_suspended(sb))
5382                         dquot_resume(sb, -1);
5383                 else if (ext4_has_feature_quota(sb)) {
5384                         err = ext4_enable_quotas(sb);
5385                         if (err)
5386                                 goto restore_opts;
5387                 }
5388         }
5389 #endif
5390
5391         *flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME);
5392         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5393         kfree(orig_data);
5394         return 0;
5395
5396 restore_opts:
5397         sb->s_flags = old_sb_flags;
5398         sbi->s_mount_opt = old_opts.s_mount_opt;
5399         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5400         sbi->s_resuid = old_opts.s_resuid;
5401         sbi->s_resgid = old_opts.s_resgid;
5402         sbi->s_commit_interval = old_opts.s_commit_interval;
5403         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5404         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5405 #ifdef CONFIG_QUOTA
5406         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5407         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5408                 to_free[i] = get_qf_name(sb, sbi, i);
5409                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
5410         }
5411         synchronize_rcu();
5412         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5413                 kfree(to_free[i]);
5414 #endif
5415         kfree(orig_data);
5416         return err;
5417 }
5418
5419 #ifdef CONFIG_QUOTA
5420 static int ext4_statfs_project(struct super_block *sb,
5421                                kprojid_t projid, struct kstatfs *buf)
5422 {
5423         struct kqid qid;
5424         struct dquot *dquot;
5425         u64 limit;
5426         u64 curblock;
5427
5428         qid = make_kqid_projid(projid);
5429         dquot = dqget(sb, qid);
5430         if (IS_ERR(dquot))
5431                 return PTR_ERR(dquot);
5432         spin_lock(&dquot->dq_dqb_lock);
5433
5434         limit = (dquot->dq_dqb.dqb_bsoftlimit ?
5435                  dquot->dq_dqb.dqb_bsoftlimit :
5436                  dquot->dq_dqb.dqb_bhardlimit) >> sb->s_blocksize_bits;
5437         if (limit && buf->f_blocks > limit) {
5438                 curblock = (dquot->dq_dqb.dqb_curspace +
5439                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5440                 buf->f_blocks = limit;
5441                 buf->f_bfree = buf->f_bavail =
5442                         (buf->f_blocks > curblock) ?
5443                          (buf->f_blocks - curblock) : 0;
5444         }
5445
5446         limit = dquot->dq_dqb.dqb_isoftlimit ?
5447                 dquot->dq_dqb.dqb_isoftlimit :
5448                 dquot->dq_dqb.dqb_ihardlimit;
5449         if (limit && buf->f_files > limit) {
5450                 buf->f_files = limit;
5451                 buf->f_ffree =
5452                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5453                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5454         }
5455
5456         spin_unlock(&dquot->dq_dqb_lock);
5457         dqput(dquot);
5458         return 0;
5459 }
5460 #endif
5461
5462 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5463 {
5464         struct super_block *sb = dentry->d_sb;
5465         struct ext4_sb_info *sbi = EXT4_SB(sb);
5466         struct ext4_super_block *es = sbi->s_es;
5467         ext4_fsblk_t overhead = 0, resv_blocks;
5468         u64 fsid;
5469         s64 bfree;
5470         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5471
5472         if (!test_opt(sb, MINIX_DF))
5473                 overhead = sbi->s_overhead;
5474
5475         buf->f_type = EXT4_SUPER_MAGIC;
5476         buf->f_bsize = sb->s_blocksize;
5477         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5478         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5479                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5480         /* prevent underflow in case that few free space is available */
5481         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5482         buf->f_bavail = buf->f_bfree -
5483                         (ext4_r_blocks_count(es) + resv_blocks);
5484         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5485                 buf->f_bavail = 0;
5486         buf->f_files = le32_to_cpu(es->s_inodes_count);
5487         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5488         buf->f_namelen = EXT4_NAME_LEN;
5489         fsid = le64_to_cpup((void *)es->s_uuid) ^
5490                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5491         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5492         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5493
5494 #ifdef CONFIG_QUOTA
5495         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5496             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5497                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5498 #endif
5499         return 0;
5500 }
5501
5502
5503 #ifdef CONFIG_QUOTA
5504
5505 /*
5506  * Helper functions so that transaction is started before we acquire dqio_sem
5507  * to keep correct lock ordering of transaction > dqio_sem
5508  */
5509 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5510 {
5511         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5512 }
5513
5514 static int ext4_write_dquot(struct dquot *dquot)
5515 {
5516         int ret, err;
5517         handle_t *handle;
5518         struct inode *inode;
5519
5520         inode = dquot_to_inode(dquot);
5521         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5522                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5523         if (IS_ERR(handle))
5524                 return PTR_ERR(handle);
5525         ret = dquot_commit(dquot);
5526         err = ext4_journal_stop(handle);
5527         if (!ret)
5528                 ret = err;
5529         return ret;
5530 }
5531
5532 static int ext4_acquire_dquot(struct dquot *dquot)
5533 {
5534         int ret, err;
5535         handle_t *handle;
5536
5537         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5538                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5539         if (IS_ERR(handle))
5540                 return PTR_ERR(handle);
5541         ret = dquot_acquire(dquot);
5542         err = ext4_journal_stop(handle);
5543         if (!ret)
5544                 ret = err;
5545         return ret;
5546 }
5547
5548 static int ext4_release_dquot(struct dquot *dquot)
5549 {
5550         int ret, err;
5551         handle_t *handle;
5552
5553         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5554                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5555         if (IS_ERR(handle)) {
5556                 /* Release dquot anyway to avoid endless cycle in dqput() */
5557                 dquot_release(dquot);
5558                 return PTR_ERR(handle);
5559         }
5560         ret = dquot_release(dquot);
5561         err = ext4_journal_stop(handle);
5562         if (!ret)
5563                 ret = err;
5564         return ret;
5565 }
5566
5567 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5568 {
5569         struct super_block *sb = dquot->dq_sb;
5570         struct ext4_sb_info *sbi = EXT4_SB(sb);
5571
5572         /* Are we journaling quotas? */
5573         if (ext4_has_feature_quota(sb) ||
5574             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5575                 dquot_mark_dquot_dirty(dquot);
5576                 return ext4_write_dquot(dquot);
5577         } else {
5578                 return dquot_mark_dquot_dirty(dquot);
5579         }
5580 }
5581
5582 static int ext4_write_info(struct super_block *sb, int type)
5583 {
5584         int ret, err;
5585         handle_t *handle;
5586
5587         /* Data block + inode block */
5588         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5589         if (IS_ERR(handle))
5590                 return PTR_ERR(handle);
5591         ret = dquot_commit_info(sb, type);
5592         err = ext4_journal_stop(handle);
5593         if (!ret)
5594                 ret = err;
5595         return ret;
5596 }
5597
5598 /*
5599  * Turn on quotas during mount time - we need to find
5600  * the quota file and such...
5601  */
5602 static int ext4_quota_on_mount(struct super_block *sb, int type)
5603 {
5604         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
5605                                         EXT4_SB(sb)->s_jquota_fmt, type);
5606 }
5607
5608 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5609 {
5610         struct ext4_inode_info *ei = EXT4_I(inode);
5611
5612         /* The first argument of lockdep_set_subclass has to be
5613          * *exactly* the same as the argument to init_rwsem() --- in
5614          * this case, in init_once() --- or lockdep gets unhappy
5615          * because the name of the lock is set using the
5616          * stringification of the argument to init_rwsem().
5617          */
5618         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
5619         lockdep_set_subclass(&ei->i_data_sem, subclass);
5620 }
5621
5622 /*
5623  * Standard function to be called on quota_on
5624  */
5625 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5626                          const struct path *path)
5627 {
5628         int err;
5629
5630         if (!test_opt(sb, QUOTA))
5631                 return -EINVAL;
5632
5633         /* Quotafile not on the same filesystem? */
5634         if (path->dentry->d_sb != sb)
5635                 return -EXDEV;
5636         /* Journaling quota? */
5637         if (EXT4_SB(sb)->s_qf_names[type]) {
5638                 /* Quotafile not in fs root? */
5639                 if (path->dentry->d_parent != sb->s_root)
5640                         ext4_msg(sb, KERN_WARNING,
5641                                 "Quota file not on filesystem root. "
5642                                 "Journaled quota will not work");
5643                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5644         } else {
5645                 /*
5646                  * Clear the flag just in case mount options changed since
5647                  * last time.
5648                  */
5649                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5650         }
5651
5652         /*
5653          * When we journal data on quota file, we have to flush journal to see
5654          * all updates to the file when we bypass pagecache...
5655          */
5656         if (EXT4_SB(sb)->s_journal &&
5657             ext4_should_journal_data(d_inode(path->dentry))) {
5658                 /*
5659                  * We don't need to lock updates but journal_flush() could
5660                  * otherwise be livelocked...
5661                  */
5662                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5663                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5664                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5665                 if (err)
5666                         return err;
5667         }
5668
5669         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5670         err = dquot_quota_on(sb, type, format_id, path);
5671         if (err) {
5672                 lockdep_set_quota_inode(path->dentry->d_inode,
5673                                              I_DATA_SEM_NORMAL);
5674         } else {
5675                 struct inode *inode = d_inode(path->dentry);
5676                 handle_t *handle;
5677
5678                 /*
5679                  * Set inode flags to prevent userspace from messing with quota
5680                  * files. If this fails, we return success anyway since quotas
5681                  * are already enabled and this is not a hard failure.
5682                  */
5683                 inode_lock(inode);
5684                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5685                 if (IS_ERR(handle))
5686                         goto unlock_inode;
5687                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5688                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5689                                 S_NOATIME | S_IMMUTABLE);
5690                 ext4_mark_inode_dirty(handle, inode);
5691                 ext4_journal_stop(handle);
5692         unlock_inode:
5693                 inode_unlock(inode);
5694         }
5695         return err;
5696 }
5697
5698 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5699                              unsigned int flags)
5700 {
5701         int err;
5702         struct inode *qf_inode;
5703         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5704                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5705                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5706                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5707         };
5708
5709         BUG_ON(!ext4_has_feature_quota(sb));
5710
5711         if (!qf_inums[type])
5712                 return -EPERM;
5713
5714         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
5715         if (IS_ERR(qf_inode)) {
5716                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5717                 return PTR_ERR(qf_inode);
5718         }
5719
5720         /* Don't account quota for quota files to avoid recursion */
5721         qf_inode->i_flags |= S_NOQUOTA;
5722         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5723         err = dquot_enable(qf_inode, type, format_id, flags);
5724         if (err)
5725                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5726         iput(qf_inode);
5727
5728         return err;
5729 }
5730
5731 /* Enable usage tracking for all quota types. */
5732 static int ext4_enable_quotas(struct super_block *sb)
5733 {
5734         int type, err = 0;
5735         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5736                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5737                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5738                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5739         };
5740         bool quota_mopt[EXT4_MAXQUOTAS] = {
5741                 test_opt(sb, USRQUOTA),
5742                 test_opt(sb, GRPQUOTA),
5743                 test_opt(sb, PRJQUOTA),
5744         };
5745
5746         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
5747         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5748                 if (qf_inums[type]) {
5749                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5750                                 DQUOT_USAGE_ENABLED |
5751                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5752                         if (err) {
5753                                 ext4_warning(sb,
5754                                         "Failed to enable quota tracking "
5755                                         "(type=%d, err=%d). Please run "
5756                                         "e2fsck to fix.", type, err);
5757                                 for (type--; type >= 0; type--)
5758                                         dquot_quota_off(sb, type);
5759
5760                                 return err;
5761                         }
5762                 }
5763         }
5764         return 0;
5765 }
5766
5767 static int ext4_quota_off(struct super_block *sb, int type)
5768 {
5769         struct inode *inode = sb_dqopt(sb)->files[type];
5770         handle_t *handle;
5771         int err;
5772
5773         /* Force all delayed allocation blocks to be allocated.
5774          * Caller already holds s_umount sem */
5775         if (test_opt(sb, DELALLOC))
5776                 sync_filesystem(sb);
5777
5778         if (!inode || !igrab(inode))
5779                 goto out;
5780
5781         err = dquot_quota_off(sb, type);
5782         if (err || ext4_has_feature_quota(sb))
5783                 goto out_put;
5784
5785         inode_lock(inode);
5786         /*
5787          * Update modification times of quota files when userspace can
5788          * start looking at them. If we fail, we return success anyway since
5789          * this is not a hard failure and quotas are already disabled.
5790          */
5791         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5792         if (IS_ERR(handle))
5793                 goto out_unlock;
5794         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
5795         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
5796         inode->i_mtime = inode->i_ctime = current_time(inode);
5797         ext4_mark_inode_dirty(handle, inode);
5798         ext4_journal_stop(handle);
5799 out_unlock:
5800         inode_unlock(inode);
5801 out_put:
5802         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
5803         iput(inode);
5804         return err;
5805 out:
5806         return dquot_quota_off(sb, type);
5807 }
5808
5809 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5810  * acquiring the locks... As quota files are never truncated and quota code
5811  * itself serializes the operations (and no one else should touch the files)
5812  * we don't have to be afraid of races */
5813 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5814                                size_t len, loff_t off)
5815 {
5816         struct inode *inode = sb_dqopt(sb)->files[type];
5817         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5818         int offset = off & (sb->s_blocksize - 1);
5819         int tocopy;
5820         size_t toread;
5821         struct buffer_head *bh;
5822         loff_t i_size = i_size_read(inode);
5823
5824         if (off > i_size)
5825                 return 0;
5826         if (off+len > i_size)
5827                 len = i_size-off;
5828         toread = len;
5829         while (toread > 0) {
5830                 tocopy = sb->s_blocksize - offset < toread ?
5831                                 sb->s_blocksize - offset : toread;
5832                 bh = ext4_bread(NULL, inode, blk, 0);
5833                 if (IS_ERR(bh))
5834                         return PTR_ERR(bh);
5835                 if (!bh)        /* A hole? */
5836                         memset(data, 0, tocopy);
5837                 else
5838                         memcpy(data, bh->b_data+offset, tocopy);
5839                 brelse(bh);
5840                 offset = 0;
5841                 toread -= tocopy;
5842                 data += tocopy;
5843                 blk++;
5844         }
5845         return len;
5846 }
5847
5848 /* Write to quotafile (we know the transaction is already started and has
5849  * enough credits) */
5850 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5851                                 const char *data, size_t len, loff_t off)
5852 {
5853         struct inode *inode = sb_dqopt(sb)->files[type];
5854         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5855         int err, offset = off & (sb->s_blocksize - 1);
5856         int retries = 0;
5857         struct buffer_head *bh;
5858         handle_t *handle = journal_current_handle();
5859
5860         if (EXT4_SB(sb)->s_journal && !handle) {
5861                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5862                         " cancelled because transaction is not started",
5863                         (unsigned long long)off, (unsigned long long)len);
5864                 return -EIO;
5865         }
5866         /*
5867          * Since we account only one data block in transaction credits,
5868          * then it is impossible to cross a block boundary.
5869          */
5870         if (sb->s_blocksize - offset < len) {
5871                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5872                         " cancelled because not block aligned",
5873                         (unsigned long long)off, (unsigned long long)len);
5874                 return -EIO;
5875         }
5876
5877         do {
5878                 bh = ext4_bread(handle, inode, blk,
5879                                 EXT4_GET_BLOCKS_CREATE |
5880                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
5881         } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
5882                  ext4_should_retry_alloc(inode->i_sb, &retries));
5883         if (IS_ERR(bh))
5884                 return PTR_ERR(bh);
5885         if (!bh)
5886                 goto out;
5887         BUFFER_TRACE(bh, "get write access");
5888         err = ext4_journal_get_write_access(handle, bh);
5889         if (err) {
5890                 brelse(bh);
5891                 return err;
5892         }
5893         lock_buffer(bh);
5894         memcpy(bh->b_data+offset, data, len);
5895         flush_dcache_page(bh->b_page);
5896         unlock_buffer(bh);
5897         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5898         brelse(bh);
5899 out:
5900         if (inode->i_size < off + len) {
5901                 i_size_write(inode, off + len);
5902                 EXT4_I(inode)->i_disksize = inode->i_size;
5903                 ext4_mark_inode_dirty(handle, inode);
5904         }
5905         return len;
5906 }
5907
5908 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid)
5909 {
5910         const struct quota_format_ops   *ops;
5911
5912         if (!sb_has_quota_loaded(sb, qid->type))
5913                 return -ESRCH;
5914         ops = sb_dqopt(sb)->ops[qid->type];
5915         if (!ops || !ops->get_next_id)
5916                 return -ENOSYS;
5917         return dquot_get_next_id(sb, qid);
5918 }
5919 #endif
5920
5921 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5922                        const char *dev_name, void *data)
5923 {
5924         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5925 }
5926
5927 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
5928 static inline void register_as_ext2(void)
5929 {
5930         int err = register_filesystem(&ext2_fs_type);
5931         if (err)
5932                 printk(KERN_WARNING
5933                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5934 }
5935
5936 static inline void unregister_as_ext2(void)
5937 {
5938         unregister_filesystem(&ext2_fs_type);
5939 }
5940
5941 static inline int ext2_feature_set_ok(struct super_block *sb)
5942 {
5943         if (ext4_has_unknown_ext2_incompat_features(sb))
5944                 return 0;
5945         if (sb_rdonly(sb))
5946                 return 1;
5947         if (ext4_has_unknown_ext2_ro_compat_features(sb))
5948                 return 0;
5949         return 1;
5950 }
5951 #else
5952 static inline void register_as_ext2(void) { }
5953 static inline void unregister_as_ext2(void) { }
5954 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5955 #endif
5956
5957 static inline void register_as_ext3(void)
5958 {
5959         int err = register_filesystem(&ext3_fs_type);
5960         if (err)
5961                 printk(KERN_WARNING
5962                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5963 }
5964
5965 static inline void unregister_as_ext3(void)
5966 {
5967         unregister_filesystem(&ext3_fs_type);
5968 }
5969
5970 static inline int ext3_feature_set_ok(struct super_block *sb)
5971 {
5972         if (ext4_has_unknown_ext3_incompat_features(sb))
5973                 return 0;
5974         if (!ext4_has_feature_journal(sb))
5975                 return 0;
5976         if (sb_rdonly(sb))
5977                 return 1;
5978         if (ext4_has_unknown_ext3_ro_compat_features(sb))
5979                 return 0;
5980         return 1;
5981 }
5982
5983 static struct file_system_type ext4_fs_type = {
5984         .owner          = THIS_MODULE,
5985         .name           = "ext4",
5986         .mount          = ext4_mount,
5987         .kill_sb        = kill_block_super,
5988         .fs_flags       = FS_REQUIRES_DEV,
5989 };
5990 MODULE_ALIAS_FS("ext4");
5991
5992 /* Shared across all ext4 file systems */
5993 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5994
5995 static int __init ext4_init_fs(void)
5996 {
5997         int i, err;
5998
5999         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6000         ext4_li_info = NULL;
6001         mutex_init(&ext4_li_mtx);
6002
6003         /* Build-time check for flags consistency */
6004         ext4_check_flag_values();
6005
6006         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6007                 init_waitqueue_head(&ext4__ioend_wq[i]);
6008
6009         err = ext4_init_es();
6010         if (err)
6011                 return err;
6012
6013         err = ext4_init_pending();
6014         if (err)
6015                 goto out6;
6016
6017         err = ext4_init_pageio();
6018         if (err)
6019                 goto out5;
6020
6021         err = ext4_init_system_zone();
6022         if (err)
6023                 goto out4;
6024
6025         err = ext4_init_sysfs();
6026         if (err)
6027                 goto out3;
6028
6029         err = ext4_init_mballoc();
6030         if (err)
6031                 goto out2;
6032         err = init_inodecache();
6033         if (err)
6034                 goto out1;
6035         register_as_ext3();
6036         register_as_ext2();
6037         err = register_filesystem(&ext4_fs_type);
6038         if (err)
6039                 goto out;
6040
6041         return 0;
6042 out:
6043         unregister_as_ext2();
6044         unregister_as_ext3();
6045         destroy_inodecache();
6046 out1:
6047         ext4_exit_mballoc();
6048 out2:
6049         ext4_exit_sysfs();
6050 out3:
6051         ext4_exit_system_zone();
6052 out4:
6053         ext4_exit_pageio();
6054 out5:
6055         ext4_exit_pending();
6056 out6:
6057         ext4_exit_es();
6058
6059         return err;
6060 }
6061
6062 static void __exit ext4_exit_fs(void)
6063 {
6064         ext4_destroy_lazyinit_thread();
6065         unregister_as_ext2();
6066         unregister_as_ext3();
6067         unregister_filesystem(&ext4_fs_type);
6068         destroy_inodecache();
6069         ext4_exit_mballoc();
6070         ext4_exit_sysfs();
6071         ext4_exit_system_zone();
6072         ext4_exit_pageio();
6073         ext4_exit_es();
6074         ext4_exit_pending();
6075 }
6076
6077 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6078 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6079 MODULE_LICENSE("GPL");
6080 MODULE_SOFTDEP("pre: crc32c");
6081 module_init(ext4_init_fs)
6082 module_exit(ext4_exit_fs)