fs/ext4/super.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/ext4/super.c
   4  *
   5  * Copyright (C) 1992, 1993, 1994, 1995
   6  * Remy Card (card@masi.ibp.fr)
   7  * Laboratoire MASI - Institut Blaise Pascal
   8  * Universite Pierre et Marie Curie (Paris VI)
   9  *
  10  *  from
  11  *
  12  *  linux/fs/minix/inode.c
  13  *
  14  *  Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  *  Big-endian to little-endian byte-swapping/bitmaps by
  17  *        David S. Miller (davem@caip.rutgers.edu), 1995
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/string.h>
  22 #include <linux/fs.h>
  23 #include <linux/time.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/backing-dev.h>
  29 #include <linux/parser.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/dax.h>
  42 #include <linux/cleancache.h>
  43 #include <linux/uaccess.h>
  44 #include <linux/iversion.h>
  45
  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 int ext4_mark_recovery_complete(struct super_block *sb,
  69                                         struct ext4_super_block *es);
  70 static int 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         if (!bdev_read_only(sb->s_bdev))
 392                 ext4_commit_super(sb, 1);
 393 }
 394
 395 /*
 396  * The del_gendisk() function uninitializes the disk-specific data
 397  * structures, including the bdi structure, without telling anyone
 398  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 399  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 400  * This is a kludge to prevent these oops until we can put in a proper
 401  * hook in del_gendisk() to inform the VFS and file system layers.
 402  */
 403 static int block_device_ejected(struct super_block *sb)
 404 {
 405         struct inode *bd_inode = sb->s_bdev->bd_inode;
 406         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 407
 408         return bdi->dev == NULL;
 409 }
 410
 411 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 412 {
 413         struct super_block              *sb = journal->j_private;
 414         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 415         int                             error = is_journal_aborted(journal);
 416         struct ext4_journal_cb_entry    *jce;
 417
 418         BUG_ON(txn->t_state == T_FINISHED);
 419
 420         ext4_process_freed_data(sb, txn->t_tid);
 421
 422         spin_lock(&sbi->s_md_lock);
 423         while (!list_empty(&txn->t_private_list)) {
 424                 jce = list_entry(txn->t_private_list.next,
 425                                  struct ext4_journal_cb_entry, jce_list);
 426                 list_del_init(&jce->jce_list);
 427                 spin_unlock(&sbi->s_md_lock);
 428                 jce->jce_func(sb, jce, error);
 429                 spin_lock(&sbi->s_md_lock);
 430         }
 431         spin_unlock(&sbi->s_md_lock);
 432 }
 433
 434 static bool system_going_down(void)
 435 {
 436         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 437                 || system_state == SYSTEM_RESTART;
 438 }
 439
 440 /* Deal with the reporting of failure conditions on a filesystem such as
 441  * inconsistencies detected or read IO failures.
 442  *
 443  * On ext2, we can store the error state of the filesystem in the
 444  * superblock.  That is not possible on ext4, because we may have other
 445  * write ordering constraints on the superblock which prevent us from
 446  * writing it out straight away; and given that the journal is about to
 447  * be aborted, we can't rely on the current, or future, transactions to
 448  * write out the superblock safely.
 449  *
 450  * We'll just use the jbd2_journal_abort() error code to record an error in
 451  * the journal instead.  On recovery, the journal will complain about
 452  * that error until we've noted it down and cleared it.
 453  */
 454
 455 static void ext4_handle_error(struct super_block *sb)
 456 {
 457         journal_t *journal = EXT4_SB(sb)->s_journal;
 458
 459         if (test_opt(sb, WARN_ON_ERROR))
 460                 WARN_ON_ONCE(1);
 461
 462         if (sb_rdonly(sb) || test_opt(sb, ERRORS_CONT))
 463                 return;
 464
 465         EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 466         if (journal)
 467                 jbd2_journal_abort(journal, -EIO);
 468         /*
 469          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 470          * could panic during 'reboot -f' as the underlying device got already
 471          * disabled.
 472          */
 473         if (test_opt(sb, ERRORS_RO) || system_going_down()) {
 474                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 475                 /*
 476                  * Make sure updated value of ->s_mount_flags will be visible
 477                  * before ->s_flags update
 478                  */
 479                 smp_wmb();
 480                 sb->s_flags |= SB_RDONLY;
 481         } else if (test_opt(sb, ERRORS_PANIC)) {
 482                 if (EXT4_SB(sb)->s_journal &&
 483                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 484                         return;
 485                 panic("EXT4-fs (device %s): panic forced after error\n",
 486                         sb->s_id);
 487         }
 488 }
 489
 490 #define ext4_error_ratelimit(sb)                                        \
 491                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 492                              "EXT4-fs error")
 493
 494 void __ext4_error(struct super_block *sb, const char *function,
 495                   unsigned int line, const char *fmt, ...)
 496 {
 497         struct va_format vaf;
 498         va_list args;
 499
 500         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 501                 return;
 502
 503         trace_ext4_error(sb, function, line);
 504         if (ext4_error_ratelimit(sb)) {
 505                 va_start(args, fmt);
 506                 vaf.fmt = fmt;
 507                 vaf.va = &args;
 508                 printk(KERN_CRIT
 509                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 510                        sb->s_id, function, line, current->comm, &vaf);
 511                 va_end(args);
 512         }
 513         save_error_info(sb, function, line);
 514         ext4_handle_error(sb);
 515 }
 516
 517 void __ext4_error_inode(struct inode *inode, const char *function,
 518                         unsigned int line, ext4_fsblk_t block,
 519                         const char *fmt, ...)
 520 {
 521         va_list args;
 522         struct va_format vaf;
 523         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 524
 525         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 526                 return;
 527
 528         trace_ext4_error(inode->i_sb, function, line);
 529         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 530         es->s_last_error_block = cpu_to_le64(block);
 531         if (ext4_error_ratelimit(inode->i_sb)) {
 532                 va_start(args, fmt);
 533                 vaf.fmt = fmt;
 534                 vaf.va = &args;
 535                 if (block)
 536                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 537                                "inode #%lu: block %llu: comm %s: %pV\n",
 538                                inode->i_sb->s_id, function, line, inode->i_ino,
 539                                block, current->comm, &vaf);
 540                 else
 541                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 542                                "inode #%lu: comm %s: %pV\n",
 543                                inode->i_sb->s_id, function, line, inode->i_ino,
 544                                current->comm, &vaf);
 545                 va_end(args);
 546         }
 547         save_error_info(inode->i_sb, function, line);
 548         ext4_handle_error(inode->i_sb);
 549 }
 550
 551 void __ext4_error_file(struct file *file, const char *function,
 552                        unsigned int line, ext4_fsblk_t block,
 553                        const char *fmt, ...)
 554 {
 555         va_list args;
 556         struct va_format vaf;
 557         struct ext4_super_block *es;
 558         struct inode *inode = file_inode(file);
 559         char pathname[80], *path;
 560
 561         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 562                 return;
 563
 564         trace_ext4_error(inode->i_sb, function, line);
 565         es = EXT4_SB(inode->i_sb)->s_es;
 566         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 567         if (ext4_error_ratelimit(inode->i_sb)) {
 568                 path = file_path(file, pathname, sizeof(pathname));
 569                 if (IS_ERR(path))
 570                         path = "(unknown)";
 571                 va_start(args, fmt);
 572                 vaf.fmt = fmt;
 573                 vaf.va = &args;
 574                 if (block)
 575                         printk(KERN_CRIT
 576                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 577                                "block %llu: comm %s: path %s: %pV\n",
 578                                inode->i_sb->s_id, function, line, inode->i_ino,
 579                                block, current->comm, path, &vaf);
 580                 else
 581                         printk(KERN_CRIT
 582                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 583                                "comm %s: path %s: %pV\n",
 584                                inode->i_sb->s_id, function, line, inode->i_ino,
 585                                current->comm, path, &vaf);
 586                 va_end(args);
 587         }
 588         save_error_info(inode->i_sb, function, line);
 589         ext4_handle_error(inode->i_sb);
 590 }
 591
 592 const char *ext4_decode_error(struct super_block *sb, int errno,
 593                               char nbuf[16])
 594 {
 595         char *errstr = NULL;
 596
 597         switch (errno) {
 598         case -EFSCORRUPTED:
 599                 errstr = "Corrupt filesystem";
 600                 break;
 601         case -EFSBADCRC:
 602                 errstr = "Filesystem failed CRC";
 603                 break;
 604         case -EIO:
 605                 errstr = "IO failure";
 606                 break;
 607         case -ENOMEM:
 608                 errstr = "Out of memory";
 609                 break;
 610         case -EROFS:
 611                 if (!sb || (EXT4_SB(sb)->s_journal &&
 612                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 613                         errstr = "Journal has aborted";
 614                 else
 615                         errstr = "Readonly filesystem";
 616                 break;
 617         default:
 618                 /* If the caller passed in an extra buffer for unknown
 619                  * errors, textualise them now.  Else we just return
 620                  * NULL. */
 621                 if (nbuf) {
 622                         /* Check for truncated error codes... */
 623                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 624                                 errstr = nbuf;
 625                 }
 626                 break;
 627         }
 628
 629         return errstr;
 630 }
 631
 632 /* __ext4_std_error decodes expected errors from journaling functions
 633  * automatically and invokes the appropriate error response.  */
 634
 635 void __ext4_std_error(struct super_block *sb, const char *function,
 636                       unsigned int line, int errno)
 637 {
 638         char nbuf[16];
 639         const char *errstr;
 640
 641         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 642                 return;
 643
 644         /* Special case: if the error is EROFS, and we're not already
 645          * inside a transaction, then there's really no point in logging
 646          * an error. */
 647         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 648                 return;
 649
 650         if (ext4_error_ratelimit(sb)) {
 651                 errstr = ext4_decode_error(sb, errno, nbuf);
 652                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 653                        sb->s_id, function, line, errstr);
 654         }
 655
 656         save_error_info(sb, function, line);
 657         ext4_handle_error(sb);
 658 }
 659
 660 /*
 661  * ext4_abort is a much stronger failure handler than ext4_error.  The
 662  * abort function may be used to deal with unrecoverable failures such
 663  * as journal IO errors or ENOMEM at a critical moment in log management.
 664  *
 665  * We unconditionally force the filesystem into an ABORT|READONLY state,
 666  * unless the error response on the fs has been set to panic in which
 667  * case we take the easy way out and panic immediately.
 668  */
 669
 670 void __ext4_abort(struct super_block *sb, const char *function,
 671                 unsigned int line, const char *fmt, ...)
 672 {
 673         struct va_format vaf;
 674         va_list args;
 675
 676         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 677                 return;
 678
 679         save_error_info(sb, function, line);
 680         va_start(args, fmt);
 681         vaf.fmt = fmt;
 682         vaf.va = &args;
 683         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 684                sb->s_id, function, line, &vaf);
 685         va_end(args);
 686
 687         if (sb_rdonly(sb) == 0) {
 688                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 689                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 690                 /*
 691                  * Make sure updated value of ->s_mount_flags will be visible
 692                  * before ->s_flags update
 693                  */
 694                 smp_wmb();
 695                 sb->s_flags |= SB_RDONLY;
 696                 if (EXT4_SB(sb)->s_journal)
 697                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 698                 save_error_info(sb, function, line);
 699         }
 700         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
 701                 if (EXT4_SB(sb)->s_journal &&
 702                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 703                         return;
 704                 panic("EXT4-fs panic from previous error\n");
 705         }
 706 }
 707
 708 void __ext4_msg(struct super_block *sb,
 709                 const char *prefix, const char *fmt, ...)
 710 {
 711         struct va_format vaf;
 712         va_list args;
 713
 714         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 715                 return;
 716
 717         va_start(args, fmt);
 718         vaf.fmt = fmt;
 719         vaf.va = &args;
 720         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 721         va_end(args);
 722 }
 723
 724 #define ext4_warning_ratelimit(sb)                                      \
 725                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 726                              "EXT4-fs warning")
 727
 728 void __ext4_warning(struct super_block *sb, const char *function,
 729                     unsigned int line, const char *fmt, ...)
 730 {
 731         struct va_format vaf;
 732         va_list args;
 733
 734         if (!ext4_warning_ratelimit(sb))
 735                 return;
 736
 737         va_start(args, fmt);
 738         vaf.fmt = fmt;
 739         vaf.va = &args;
 740         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 741                sb->s_id, function, line, &vaf);
 742         va_end(args);
 743 }
 744
 745 void __ext4_warning_inode(const struct inode *inode, const char *function,
 746                           unsigned int line, const char *fmt, ...)
 747 {
 748         struct va_format vaf;
 749         va_list args;
 750
 751         if (!ext4_warning_ratelimit(inode->i_sb))
 752                 return;
 753
 754         va_start(args, fmt);
 755         vaf.fmt = fmt;
 756         vaf.va = &args;
 757         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 758                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 759                function, line, inode->i_ino, current->comm, &vaf);
 760         va_end(args);
 761 }
 762
 763 void __ext4_grp_locked_error(const char *function, unsigned int line,
 764                              struct super_block *sb, ext4_group_t grp,
 765                              unsigned long ino, ext4_fsblk_t block,
 766                              const char *fmt, ...)
 767 __releases(bitlock)
 768 __acquires(bitlock)
 769 {
 770         struct va_format vaf;
 771         va_list args;
 772         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 773
 774         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 775                 return;
 776
 777         trace_ext4_error(sb, function, line);
 778         es->s_last_error_ino = cpu_to_le32(ino);
 779         es->s_last_error_block = cpu_to_le64(block);
 780         __save_error_info(sb, function, line);
 781
 782         if (ext4_error_ratelimit(sb)) {
 783                 va_start(args, fmt);
 784                 vaf.fmt = fmt;
 785                 vaf.va = &args;
 786                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 787                        sb->s_id, function, line, grp);
 788                 if (ino)
 789                         printk(KERN_CONT "inode %lu: ", ino);
 790                 if (block)
 791                         printk(KERN_CONT "block %llu:",
 792                                (unsigned long long) block);
 793                 printk(KERN_CONT "%pV\n", &vaf);
 794                 va_end(args);
 795         }
 796
 797         if (test_opt(sb, WARN_ON_ERROR))
 798                 WARN_ON_ONCE(1);
 799
 800         if (test_opt(sb, ERRORS_CONT)) {
 801                 ext4_commit_super(sb, 0);
 802                 return;
 803         }
 804
 805         ext4_unlock_group(sb, grp);
 806         ext4_commit_super(sb, 1);
 807         ext4_handle_error(sb);
 808         /*
 809          * We only get here in the ERRORS_RO case; relocking the group
 810          * may be dangerous, but nothing bad will happen since the
 811          * filesystem will have already been marked read/only and the
 812          * journal has been aborted.  We return 1 as a hint to callers
 813          * who might what to use the return value from
 814          * ext4_grp_locked_error() to distinguish between the
 815          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 816          * aggressively from the ext4 function in question, with a
 817          * more appropriate error code.
 818          */
 819         ext4_lock_group(sb, grp);
 820         return;
 821 }
 822
 823 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
 824                                      ext4_group_t group,
 825                                      unsigned int flags)
 826 {
 827         struct ext4_sb_info *sbi = EXT4_SB(sb);
 828         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
 829         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
 830         int ret;
 831
 832         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
 833                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
 834                                             &grp->bb_state);
 835                 if (!ret)
 836                         percpu_counter_sub(&sbi->s_freeclusters_counter,
 837                                            grp->bb_free);
 838         }
 839
 840         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
 841                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
 842                                             &grp->bb_state);
 843                 if (!ret && gdp) {
 844                         int count;
 845
 846                         count = ext4_free_inodes_count(sb, gdp);
 847                         percpu_counter_sub(&sbi->s_freeinodes_counter,
 848                                            count);
 849                 }
 850         }
 851 }
 852
 853 void ext4_update_dynamic_rev(struct super_block *sb)
 854 {
 855         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 856
 857         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 858                 return;
 859
 860         ext4_warning(sb,
 861                      "updating to rev %d because of new feature flag, "
 862                      "running e2fsck is recommended",
 863                      EXT4_DYNAMIC_REV);
 864
 865         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 866         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 867         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 868         /* leave es->s_feature_*compat flags alone */
 869         /* es->s_uuid will be set by e2fsck if empty */
 870
 871         /*
 872          * The rest of the superblock fields should be zero, and if not it
 873          * means they are likely already in use, so leave them alone.  We
 874          * can leave it up to e2fsck to clean up any inconsistencies there.
 875          */
 876 }
 877
 878 /*
 879  * Open the external journal device
 880  */
 881 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 882 {
 883         struct block_device *bdev;
 884         char b[BDEVNAME_SIZE];
 885
 886         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 887         if (IS_ERR(bdev))
 888                 goto fail;
 889         return bdev;
 890
 891 fail:
 892         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 893                         __bdevname(dev, b), PTR_ERR(bdev));
 894         return NULL;
 895 }
 896
 897 /*
 898  * Release the journal device
 899  */
 900 static void ext4_blkdev_put(struct block_device *bdev)
 901 {
 902         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 903 }
 904
 905 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 906 {
 907         struct block_device *bdev;
 908         bdev = sbi->journal_bdev;
 909         if (bdev) {
 910                 ext4_blkdev_put(bdev);
 911                 sbi->journal_bdev = NULL;
 912         }
 913 }
 914
 915 static inline struct inode *orphan_list_entry(struct list_head *l)
 916 {
 917         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 918 }
 919
 920 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 921 {
 922         struct list_head *l;
 923
 924         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 925                  le32_to_cpu(sbi->s_es->s_last_orphan));
 926
 927         printk(KERN_ERR "sb_info orphan list:\n");
 928         list_for_each(l, &sbi->s_orphan) {
 929                 struct inode *inode = orphan_list_entry(l);
 930                 printk(KERN_ERR "  "
 931                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 932                        inode->i_sb->s_id, inode->i_ino, inode,
 933                        inode->i_mode, inode->i_nlink,
 934                        NEXT_ORPHAN(inode));
 935         }
 936 }
 937
 938 #ifdef CONFIG_QUOTA
 939 static int ext4_quota_off(struct super_block *sb, int type);
 940
 941 static inline void ext4_quota_off_umount(struct super_block *sb)
 942 {
 943         int type;
 944
 945         /* Use our quota_off function to clear inode flags etc. */
 946         for (type = 0; type < EXT4_MAXQUOTAS; type++)
 947                 ext4_quota_off(sb, type);
 948 }
 949
 950 /*
 951  * This is a helper function which is used in the mount/remount
 952  * codepaths (which holds s_umount) to fetch the quota file name.
 953  */
 954 static inline char *get_qf_name(struct super_block *sb,
 955                                 struct ext4_sb_info *sbi,
 956                                 int type)
 957 {
 958         return rcu_dereference_protected(sbi->s_qf_names[type],
 959                                          lockdep_is_held(&sb->s_umount));
 960 }
 961 #else
 962 static inline void ext4_quota_off_umount(struct super_block *sb)
 963 {
 964 }
 965 #endif
 966
 967 static void ext4_put_super(struct super_block *sb)
 968 {
 969         struct ext4_sb_info *sbi = EXT4_SB(sb);
 970         struct ext4_super_block *es = sbi->s_es;
 971         struct buffer_head **group_desc;
 972         struct flex_groups **flex_groups;
 973         int aborted = 0;
 974         int i, err;
 975
 976         ext4_unregister_li_request(sb);
 977         ext4_quota_off_umount(sb);
 978
 979         destroy_workqueue(sbi->rsv_conversion_wq);
 980
 981         if (sbi->s_journal) {
 982                 aborted = is_journal_aborted(sbi->s_journal);
 983                 err = jbd2_journal_destroy(sbi->s_journal);
 984                 sbi->s_journal = NULL;
 985                 if ((err < 0) && !aborted)
 986                         ext4_abort(sb, "Couldn't clean up the journal");
 987         }
 988
 989         ext4_unregister_sysfs(sb);
 990         ext4_es_unregister_shrinker(sbi);
 991         del_timer_sync(&sbi->s_err_report);
 992         ext4_release_system_zone(sb);
 993         ext4_mb_release(sb);
 994         ext4_ext_release(sb);
 995
 996         if (!sb_rdonly(sb) && !aborted) {
 997                 ext4_clear_feature_journal_needs_recovery(sb);
 998                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 999         }
1000         if (!sb_rdonly(sb))
1001                 ext4_commit_super(sb, 1);
1002
1003         rcu_read_lock();
1004         group_desc = rcu_dereference(sbi->s_group_desc);
1005         for (i = 0; i < sbi->s_gdb_count; i++)
1006                 brelse(group_desc[i]);
1007         kvfree(group_desc);
1008         flex_groups = rcu_dereference(sbi->s_flex_groups);
1009         if (flex_groups) {
1010                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1011                         kvfree(flex_groups[i]);
1012                 kvfree(flex_groups);
1013         }
1014         rcu_read_unlock();
1015         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1016         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1017         percpu_counter_destroy(&sbi->s_dirs_counter);
1018         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1019         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1020 #ifdef CONFIG_QUOTA
1021         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1022                 kfree(get_qf_name(sb, sbi, i));
1023 #endif
1024
1025         /* Debugging code just in case the in-memory inode orphan list
1026          * isn't empty.  The on-disk one can be non-empty if we've
1027          * detected an error and taken the fs readonly, but the
1028          * in-memory list had better be clean by this point. */
1029         if (!list_empty(&sbi->s_orphan))
1030                 dump_orphan_list(sb, sbi);
1031         J_ASSERT(list_empty(&sbi->s_orphan));
1032
1033         sync_blockdev(sb->s_bdev);
1034         invalidate_bdev(sb->s_bdev);
1035         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
1036                 /*
1037                  * Invalidate the journal device's buffers.  We don't want them
1038                  * floating about in memory - the physical journal device may
1039                  * hotswapped, and it breaks the `ro-after' testing code.
1040                  */
1041                 sync_blockdev(sbi->journal_bdev);
1042                 invalidate_bdev(sbi->journal_bdev);
1043                 ext4_blkdev_remove(sbi);
1044         }
1045         if (sbi->s_ea_inode_cache) {
1046                 ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1047                 sbi->s_ea_inode_cache = NULL;
1048         }
1049         if (sbi->s_ea_block_cache) {
1050                 ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1051                 sbi->s_ea_block_cache = NULL;
1052         }
1053         if (sbi->s_mmp_tsk)
1054                 kthread_stop(sbi->s_mmp_tsk);
1055         brelse(sbi->s_sbh);
1056         sb->s_fs_info = NULL;
1057         /*
1058          * Now that we are completely done shutting down the
1059          * superblock, we need to actually destroy the kobject.
1060          */
1061         kobject_put(&sbi->s_kobj);
1062         wait_for_completion(&sbi->s_kobj_unregister);
1063         if (sbi->s_chksum_driver)
1064                 crypto_free_shash(sbi->s_chksum_driver);
1065         kfree(sbi->s_blockgroup_lock);
1066         fs_put_dax(sbi->s_daxdev);
1067         kfree(sbi);
1068 }
1069
1070 static struct kmem_cache *ext4_inode_cachep;
1071
1072 /*
1073  * Called inside transaction, so use GFP_NOFS
1074  */
1075 static struct inode *ext4_alloc_inode(struct super_block *sb)
1076 {
1077         struct ext4_inode_info *ei;
1078
1079         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1080         if (!ei)
1081                 return NULL;
1082
1083         inode_set_iversion(&ei->vfs_inode, 1);
1084         spin_lock_init(&ei->i_raw_lock);
1085         INIT_LIST_HEAD(&ei->i_prealloc_list);
1086         spin_lock_init(&ei->i_prealloc_lock);
1087         ext4_es_init_tree(&ei->i_es_tree);
1088         rwlock_init(&ei->i_es_lock);
1089         INIT_LIST_HEAD(&ei->i_es_list);
1090         ei->i_es_all_nr = 0;
1091         ei->i_es_shk_nr = 0;
1092         ei->i_es_shrink_lblk = 0;
1093         ei->i_reserved_data_blocks = 0;
1094         ei->i_da_metadata_calc_len = 0;
1095         ei->i_da_metadata_calc_last_lblock = 0;
1096         spin_lock_init(&(ei->i_block_reservation_lock));
1097 #ifdef CONFIG_QUOTA
1098         ei->i_reserved_quota = 0;
1099         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1100 #endif
1101         ei->jinode = NULL;
1102         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1103         spin_lock_init(&ei->i_completed_io_lock);
1104         ei->i_sync_tid = 0;
1105         ei->i_datasync_tid = 0;
1106         atomic_set(&ei->i_unwritten, 0);
1107         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1108         return &ei->vfs_inode;
1109 }
1110
1111 static int ext4_drop_inode(struct inode *inode)
1112 {
1113         int drop = generic_drop_inode(inode);
1114
1115         trace_ext4_drop_inode(inode, drop);
1116         return drop;
1117 }
1118
1119 static void ext4_i_callback(struct rcu_head *head)
1120 {
1121         struct inode *inode = container_of(head, struct inode, i_rcu);
1122         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1123 }
1124
1125 static void ext4_destroy_inode(struct inode *inode)
1126 {
1127         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1128                 ext4_msg(inode->i_sb, KERN_ERR,
1129                          "Inode %lu (%p): orphan list check failed!",
1130                          inode->i_ino, EXT4_I(inode));
1131                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1132                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1133                                 true);
1134                 dump_stack();
1135         }
1136         call_rcu(&inode->i_rcu, ext4_i_callback);
1137 }
1138
1139 static void init_once(void *foo)
1140 {
1141         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1142
1143         INIT_LIST_HEAD(&ei->i_orphan);
1144         init_rwsem(&ei->xattr_sem);
1145         init_rwsem(&ei->i_data_sem);
1146         init_rwsem(&ei->i_mmap_sem);
1147         inode_init_once(&ei->vfs_inode);
1148 }
1149
1150 static int __init init_inodecache(void)
1151 {
1152         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1153                                 sizeof(struct ext4_inode_info), 0,
1154                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1155                                         SLAB_ACCOUNT),
1156                                 offsetof(struct ext4_inode_info, i_data),
1157                                 sizeof_field(struct ext4_inode_info, i_data),
1158                                 init_once);
1159         if (ext4_inode_cachep == NULL)
1160                 return -ENOMEM;
1161         return 0;
1162 }
1163
1164 static void destroy_inodecache(void)
1165 {
1166         /*
1167          * Make sure all delayed rcu free inodes are flushed before we
1168          * destroy cache.
1169          */
1170         rcu_barrier();
1171         kmem_cache_destroy(ext4_inode_cachep);
1172 }
1173
1174 void ext4_clear_inode(struct inode *inode)
1175 {
1176         invalidate_inode_buffers(inode);
1177         clear_inode(inode);
1178         dquot_drop(inode);
1179         ext4_discard_preallocations(inode);
1180         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1181         if (EXT4_I(inode)->jinode) {
1182                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1183                                                EXT4_I(inode)->jinode);
1184                 jbd2_free_inode(EXT4_I(inode)->jinode);
1185                 EXT4_I(inode)->jinode = NULL;
1186         }
1187         fscrypt_put_encryption_info(inode);
1188 }
1189
1190 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1191                                         u64 ino, u32 generation)
1192 {
1193         struct inode *inode;
1194
1195         /*
1196          * Currently we don't know the generation for parent directory, so
1197          * a generation of 0 means "accept any"
1198          */
1199         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1200         if (IS_ERR(inode))
1201                 return ERR_CAST(inode);
1202         if (generation && inode->i_generation != generation) {
1203                 iput(inode);
1204                 return ERR_PTR(-ESTALE);
1205         }
1206
1207         return inode;
1208 }
1209
1210 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1211                                         int fh_len, int fh_type)
1212 {
1213         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1214                                     ext4_nfs_get_inode);
1215 }
1216
1217 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1218                                         int fh_len, int fh_type)
1219 {
1220         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1221                                     ext4_nfs_get_inode);
1222 }
1223
1224 static int ext4_nfs_commit_metadata(struct inode *inode)
1225 {
1226         struct writeback_control wbc = {
1227                 .sync_mode = WB_SYNC_ALL
1228         };
1229
1230         trace_ext4_nfs_commit_metadata(inode);
1231         return ext4_write_inode(inode, &wbc);
1232 }
1233
1234 /*
1235  * Try to release metadata pages (indirect blocks, directories) which are
1236  * mapped via the block device.  Since these pages could have journal heads
1237  * which would prevent try_to_free_buffers() from freeing them, we must use
1238  * jbd2 layer's try_to_free_buffers() function to release them.
1239  */
1240 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1241                                  gfp_t wait)
1242 {
1243         journal_t *journal = EXT4_SB(sb)->s_journal;
1244
1245         WARN_ON(PageChecked(page));
1246         if (!page_has_buffers(page))
1247                 return 0;
1248         if (journal)
1249                 return jbd2_journal_try_to_free_buffers(journal, page,
1250                                                 wait & ~__GFP_DIRECT_RECLAIM);
1251         return try_to_free_buffers(page);
1252 }
1253
1254 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1255 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1256 {
1257         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1258                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1259 }
1260
1261 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1262                                                         void *fs_data)
1263 {
1264         handle_t *handle = fs_data;
1265         int res, res2, credits, retries = 0;
1266
1267         /*
1268          * Encrypting the root directory is not allowed because e2fsck expects
1269          * lost+found to exist and be unencrypted, and encrypting the root
1270          * directory would imply encrypting the lost+found directory as well as
1271          * the filename "lost+found" itself.
1272          */
1273         if (inode->i_ino == EXT4_ROOT_INO)
1274                 return -EPERM;
1275
1276         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1277                 return -EINVAL;
1278
1279         res = ext4_convert_inline_data(inode);
1280         if (res)
1281                 return res;
1282
1283         /*
1284          * If a journal handle was specified, then the encryption context is
1285          * being set on a new inode via inheritance and is part of a larger
1286          * transaction to create the inode.  Otherwise the encryption context is
1287          * being set on an existing inode in its own transaction.  Only in the
1288          * latter case should the "retry on ENOSPC" logic be used.
1289          */
1290
1291         if (handle) {
1292                 res = ext4_xattr_set_handle(handle, inode,
1293                                             EXT4_XATTR_INDEX_ENCRYPTION,
1294                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1295                                             ctx, len, 0);
1296                 if (!res) {
1297                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1298                         ext4_clear_inode_state(inode,
1299                                         EXT4_STATE_MAY_INLINE_DATA);
1300                         /*
1301                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1302                          * S_DAX may be disabled
1303                          */
1304                         ext4_set_inode_flags(inode);
1305                 }
1306                 return res;
1307         }
1308
1309         res = dquot_initialize(inode);
1310         if (res)
1311                 return res;
1312 retry:
1313         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1314                                      &credits);
1315         if (res)
1316                 return res;
1317
1318         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1319         if (IS_ERR(handle))
1320                 return PTR_ERR(handle);
1321
1322         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1323                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1324                                     ctx, len, 0);
1325         if (!res) {
1326                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1327                 /*
1328                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1329                  * S_DAX may be disabled
1330                  */
1331                 ext4_set_inode_flags(inode);
1332                 res = ext4_mark_inode_dirty(handle, inode);
1333                 if (res)
1334                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1335         }
1336         res2 = ext4_journal_stop(handle);
1337
1338         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1339                 goto retry;
1340         if (!res)
1341                 res = res2;
1342         return res;
1343 }
1344
1345 static bool ext4_dummy_context(struct inode *inode)
1346 {
1347         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1348 }
1349
1350 static const struct fscrypt_operations ext4_cryptops = {
1351         .key_prefix             = "ext4:",
1352         .get_context            = ext4_get_context,
1353         .set_context            = ext4_set_context,
1354         .dummy_context          = ext4_dummy_context,
1355         .empty_dir              = ext4_empty_dir,
1356         .max_namelen            = EXT4_NAME_LEN,
1357 };
1358 #endif
1359
1360 #ifdef CONFIG_QUOTA
1361 static const char * const quotatypes[] = INITQFNAMES;
1362 #define QTYPE2NAME(t) (quotatypes[t])
1363
1364 static int ext4_write_dquot(struct dquot *dquot);
1365 static int ext4_acquire_dquot(struct dquot *dquot);
1366 static int ext4_release_dquot(struct dquot *dquot);
1367 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1368 static int ext4_write_info(struct super_block *sb, int type);
1369 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1370                          const struct path *path);
1371 static int ext4_quota_on_mount(struct super_block *sb, int type);
1372 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1373                                size_t len, loff_t off);
1374 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1375                                 const char *data, size_t len, loff_t off);
1376 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1377                              unsigned int flags);
1378 static int ext4_enable_quotas(struct super_block *sb);
1379 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid);
1380
1381 static struct dquot **ext4_get_dquots(struct inode *inode)
1382 {
1383         return EXT4_I(inode)->i_dquot;
1384 }
1385
1386 static const struct dquot_operations ext4_quota_operations = {
1387         .get_reserved_space     = ext4_get_reserved_space,
1388         .write_dquot            = ext4_write_dquot,
1389         .acquire_dquot          = ext4_acquire_dquot,
1390         .release_dquot          = ext4_release_dquot,
1391         .mark_dirty             = ext4_mark_dquot_dirty,
1392         .write_info             = ext4_write_info,
1393         .alloc_dquot            = dquot_alloc,
1394         .destroy_dquot          = dquot_destroy,
1395         .get_projid             = ext4_get_projid,
1396         .get_inode_usage        = ext4_get_inode_usage,
1397         .get_next_id            = ext4_get_next_id,
1398 };
1399
1400 static const struct quotactl_ops ext4_qctl_operations = {
1401         .quota_on       = ext4_quota_on,
1402         .quota_off      = ext4_quota_off,
1403         .quota_sync     = dquot_quota_sync,
1404         .get_state      = dquot_get_state,
1405         .set_info       = dquot_set_dqinfo,
1406         .get_dqblk      = dquot_get_dqblk,
1407         .set_dqblk      = dquot_set_dqblk,
1408         .get_nextdqblk  = dquot_get_next_dqblk,
1409 };
1410 #endif
1411
1412 static const struct super_operations ext4_sops = {
1413         .alloc_inode    = ext4_alloc_inode,
1414         .destroy_inode  = ext4_destroy_inode,
1415         .write_inode    = ext4_write_inode,
1416         .dirty_inode    = ext4_dirty_inode,
1417         .drop_inode     = ext4_drop_inode,
1418         .evict_inode    = ext4_evict_inode,
1419         .put_super      = ext4_put_super,
1420         .sync_fs        = ext4_sync_fs,
1421         .freeze_fs      = ext4_freeze,
1422         .unfreeze_fs    = ext4_unfreeze,
1423         .statfs         = ext4_statfs,
1424         .remount_fs     = ext4_remount,
1425         .show_options   = ext4_show_options,
1426 #ifdef CONFIG_QUOTA
1427         .quota_read     = ext4_quota_read,
1428         .quota_write    = ext4_quota_write,
1429         .get_dquots     = ext4_get_dquots,
1430 #endif
1431         .bdev_try_to_free_page = bdev_try_to_free_page,
1432 };
1433
1434 static const struct export_operations ext4_export_ops = {
1435         .fh_to_dentry = ext4_fh_to_dentry,
1436         .fh_to_parent = ext4_fh_to_parent,
1437         .get_parent = ext4_get_parent,
1438         .commit_metadata = ext4_nfs_commit_metadata,
1439 };
1440
1441 enum {
1442         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1443         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1444         Opt_nouid32, Opt_debug, Opt_removed,
1445         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1446         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1447         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1448         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1449         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1450         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1451         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1452         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1453         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1454         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1455         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1456         Opt_nowarn_on_error, Opt_mblk_io_submit,
1457         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1458         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1459         Opt_inode_readahead_blks, Opt_journal_ioprio,
1460         Opt_dioread_nolock, Opt_dioread_lock,
1461         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1462         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1463 };
1464
1465 static const match_table_t tokens = {
1466         {Opt_bsd_df, "bsddf"},
1467         {Opt_minix_df, "minixdf"},
1468         {Opt_grpid, "grpid"},
1469         {Opt_grpid, "bsdgroups"},
1470         {Opt_nogrpid, "nogrpid"},
1471         {Opt_nogrpid, "sysvgroups"},
1472         {Opt_resgid, "resgid=%u"},
1473         {Opt_resuid, "resuid=%u"},
1474         {Opt_sb, "sb=%u"},
1475         {Opt_err_cont, "errors=continue"},
1476         {Opt_err_panic, "errors=panic"},
1477         {Opt_err_ro, "errors=remount-ro"},
1478         {Opt_nouid32, "nouid32"},
1479         {Opt_debug, "debug"},
1480         {Opt_removed, "oldalloc"},
1481         {Opt_removed, "orlov"},
1482         {Opt_user_xattr, "user_xattr"},
1483         {Opt_nouser_xattr, "nouser_xattr"},
1484         {Opt_acl, "acl"},
1485         {Opt_noacl, "noacl"},
1486         {Opt_noload, "norecovery"},
1487         {Opt_noload, "noload"},
1488         {Opt_removed, "nobh"},
1489         {Opt_removed, "bh"},
1490         {Opt_commit, "commit=%u"},
1491         {Opt_min_batch_time, "min_batch_time=%u"},
1492         {Opt_max_batch_time, "max_batch_time=%u"},
1493         {Opt_journal_dev, "journal_dev=%u"},
1494         {Opt_journal_path, "journal_path=%s"},
1495         {Opt_journal_checksum, "journal_checksum"},
1496         {Opt_nojournal_checksum, "nojournal_checksum"},
1497         {Opt_journal_async_commit, "journal_async_commit"},
1498         {Opt_abort, "abort"},
1499         {Opt_data_journal, "data=journal"},
1500         {Opt_data_ordered, "data=ordered"},
1501         {Opt_data_writeback, "data=writeback"},
1502         {Opt_data_err_abort, "data_err=abort"},
1503         {Opt_data_err_ignore, "data_err=ignore"},
1504         {Opt_offusrjquota, "usrjquota="},
1505         {Opt_usrjquota, "usrjquota=%s"},
1506         {Opt_offgrpjquota, "grpjquota="},
1507         {Opt_grpjquota, "grpjquota=%s"},
1508         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1509         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1510         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1511         {Opt_grpquota, "grpquota"},
1512         {Opt_noquota, "noquota"},
1513         {Opt_quota, "quota"},
1514         {Opt_usrquota, "usrquota"},
1515         {Opt_prjquota, "prjquota"},
1516         {Opt_barrier, "barrier=%u"},
1517         {Opt_barrier, "barrier"},
1518         {Opt_nobarrier, "nobarrier"},
1519         {Opt_i_version, "i_version"},
1520         {Opt_dax, "dax"},
1521         {Opt_stripe, "stripe=%u"},
1522         {Opt_delalloc, "delalloc"},
1523         {Opt_warn_on_error, "warn_on_error"},
1524         {Opt_nowarn_on_error, "nowarn_on_error"},
1525         {Opt_lazytime, "lazytime"},
1526         {Opt_nolazytime, "nolazytime"},
1527         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1528         {Opt_nodelalloc, "nodelalloc"},
1529         {Opt_removed, "mblk_io_submit"},
1530         {Opt_removed, "nomblk_io_submit"},
1531         {Opt_block_validity, "block_validity"},
1532         {Opt_noblock_validity, "noblock_validity"},
1533         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1534         {Opt_journal_ioprio, "journal_ioprio=%u"},
1535         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1536         {Opt_auto_da_alloc, "auto_da_alloc"},
1537         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1538         {Opt_dioread_nolock, "dioread_nolock"},
1539         {Opt_dioread_lock, "dioread_lock"},
1540         {Opt_discard, "discard"},
1541         {Opt_nodiscard, "nodiscard"},
1542         {Opt_init_itable, "init_itable=%u"},
1543         {Opt_init_itable, "init_itable"},
1544         {Opt_noinit_itable, "noinit_itable"},
1545         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1546         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1547         {Opt_nombcache, "nombcache"},
1548         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1549         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1550         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1551         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1552         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1553         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1554         {Opt_err, NULL},
1555 };
1556
1557 static ext4_fsblk_t get_sb_block(void **data)
1558 {
1559         ext4_fsblk_t    sb_block;
1560         char            *options = (char *) *data;
1561
1562         if (!options || strncmp(options, "sb=", 3) != 0)
1563                 return 1;       /* Default location */
1564
1565         options += 3;
1566         /* TODO: use simple_strtoll with >32bit ext4 */
1567         sb_block = simple_strtoul(options, &options, 0);
1568         if (*options && *options != ',') {
1569                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1570                        (char *) *data);
1571                 return 1;
1572         }
1573         if (*options == ',')
1574                 options++;
1575         *data = (void *) options;
1576
1577         return sb_block;
1578 }
1579
1580 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1581 static const char deprecated_msg[] =
1582         "Mount option \"%s\" will be removed by %s\n"
1583         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1584
1585 #ifdef CONFIG_QUOTA
1586 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1587 {
1588         struct ext4_sb_info *sbi = EXT4_SB(sb);
1589         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1590         int ret = -1;
1591
1592         if (sb_any_quota_loaded(sb) && !old_qname) {
1593                 ext4_msg(sb, KERN_ERR,
1594                         "Cannot change journaled "
1595                         "quota options when quota turned on");
1596                 return -1;
1597         }
1598         if (ext4_has_feature_quota(sb)) {
1599                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1600                          "ignored when QUOTA feature is enabled");
1601                 return 1;
1602         }
1603         qname = match_strdup(args);
1604         if (!qname) {
1605                 ext4_msg(sb, KERN_ERR,
1606                         "Not enough memory for storing quotafile name");
1607                 return -1;
1608         }
1609         if (old_qname) {
1610                 if (strcmp(old_qname, qname) == 0)
1611                         ret = 1;
1612                 else
1613                         ext4_msg(sb, KERN_ERR,
1614                                  "%s quota file already specified",
1615                                  QTYPE2NAME(qtype));
1616                 goto errout;
1617         }
1618         if (strchr(qname, '/')) {
1619                 ext4_msg(sb, KERN_ERR,
1620                         "quotafile must be on filesystem root");
1621                 goto errout;
1622         }
1623         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1624         set_opt(sb, QUOTA);
1625         return 1;
1626 errout:
1627         kfree(qname);
1628         return ret;
1629 }
1630
1631 static int clear_qf_name(struct super_block *sb, int qtype)
1632 {
1633
1634         struct ext4_sb_info *sbi = EXT4_SB(sb);
1635         char *old_qname = get_qf_name(sb, sbi, qtype);
1636
1637         if (sb_any_quota_loaded(sb) && old_qname) {
1638                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1639                         " when quota turned on");
1640                 return -1;
1641         }
1642         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1643         synchronize_rcu();
1644         kfree(old_qname);
1645         return 1;
1646 }
1647 #endif
1648
1649 #define MOPT_SET        0x0001
1650 #define MOPT_CLEAR      0x0002
1651 #define MOPT_NOSUPPORT  0x0004
1652 #define MOPT_EXPLICIT   0x0008
1653 #define MOPT_CLEAR_ERR  0x0010
1654 #define MOPT_GTE0       0x0020
1655 #ifdef CONFIG_QUOTA
1656 #define MOPT_Q          0
1657 #define MOPT_QFMT       0x0040
1658 #else
1659 #define MOPT_Q          MOPT_NOSUPPORT
1660 #define MOPT_QFMT       MOPT_NOSUPPORT
1661 #endif
1662 #define MOPT_DATAJ      0x0080
1663 #define MOPT_NO_EXT2    0x0100
1664 #define MOPT_NO_EXT3    0x0200
1665 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1666 #define MOPT_STRING     0x0400
1667
1668 static const struct mount_opts {
1669         int     token;
1670         int     mount_opt;
1671         int     flags;
1672 } ext4_mount_opts[] = {
1673         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1674         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1675         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1676         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1677         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1678         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1679         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1680          MOPT_EXT4_ONLY | MOPT_SET},
1681         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1682          MOPT_EXT4_ONLY | MOPT_CLEAR},
1683         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1684         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1685         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1686          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1687         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1688          MOPT_EXT4_ONLY | MOPT_CLEAR},
1689         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1690         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1691         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1692          MOPT_EXT4_ONLY | MOPT_CLEAR},
1693         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1694          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1695         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1696                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1697          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1698         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1699         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1700         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1701         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1702         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1703          MOPT_NO_EXT2},
1704         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1705          MOPT_NO_EXT2},
1706         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1707         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1708         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1709         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1710         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1711         {Opt_commit, 0, MOPT_GTE0},
1712         {Opt_max_batch_time, 0, MOPT_GTE0},
1713         {Opt_min_batch_time, 0, MOPT_GTE0},
1714         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1715         {Opt_init_itable, 0, MOPT_GTE0},
1716         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1717         {Opt_stripe, 0, MOPT_GTE0},
1718         {Opt_resuid, 0, MOPT_GTE0},
1719         {Opt_resgid, 0, MOPT_GTE0},
1720         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1721         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1722         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1723         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1724         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1725         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1726          MOPT_NO_EXT2 | MOPT_DATAJ},
1727         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1728         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1729 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1730         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1731         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1732 #else
1733         {Opt_acl, 0, MOPT_NOSUPPORT},
1734         {Opt_noacl, 0, MOPT_NOSUPPORT},
1735 #endif
1736         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1737         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1738         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1739         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1740         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1741                                                         MOPT_SET | MOPT_Q},
1742         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1743                                                         MOPT_SET | MOPT_Q},
1744         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1745                                                         MOPT_SET | MOPT_Q},
1746         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1747                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1748                                                         MOPT_CLEAR | MOPT_Q},
1749         {Opt_usrjquota, 0, MOPT_Q | MOPT_STRING},
1750         {Opt_grpjquota, 0, MOPT_Q | MOPT_STRING},
1751         {Opt_offusrjquota, 0, MOPT_Q},
1752         {Opt_offgrpjquota, 0, MOPT_Q},
1753         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1754         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1755         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1756         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1757         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1758         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1759         {Opt_err, 0, 0}
1760 };
1761
1762 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1763                             substring_t *args, unsigned long *journal_devnum,
1764                             unsigned int *journal_ioprio, int is_remount)
1765 {
1766         struct ext4_sb_info *sbi = EXT4_SB(sb);
1767         const struct mount_opts *m;
1768         kuid_t uid;
1769         kgid_t gid;
1770         int arg = 0;
1771
1772 #ifdef CONFIG_QUOTA
1773         if (token == Opt_usrjquota)
1774                 return set_qf_name(sb, USRQUOTA, &args[0]);
1775         else if (token == Opt_grpjquota)
1776                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1777         else if (token == Opt_offusrjquota)
1778                 return clear_qf_name(sb, USRQUOTA);
1779         else if (token == Opt_offgrpjquota)
1780                 return clear_qf_name(sb, GRPQUOTA);
1781 #endif
1782         switch (token) {
1783         case Opt_noacl:
1784         case Opt_nouser_xattr:
1785                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1786                 break;
1787         case Opt_sb:
1788                 return 1;       /* handled by get_sb_block() */
1789         case Opt_removed:
1790                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1791                 return 1;
1792         case Opt_abort:
1793                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1794                 return 1;
1795         case Opt_i_version:
1796                 sb->s_flags |= SB_I_VERSION;
1797                 return 1;
1798         case Opt_lazytime:
1799                 sb->s_flags |= SB_LAZYTIME;
1800                 return 1;
1801         case Opt_nolazytime:
1802                 sb->s_flags &= ~SB_LAZYTIME;
1803                 return 1;
1804         }
1805
1806         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1807                 if (token == m->token)
1808                         break;
1809
1810         if (m->token == Opt_err) {
1811                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1812                          "or missing value", opt);
1813                 return -1;
1814         }
1815
1816         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1817                 ext4_msg(sb, KERN_ERR,
1818                          "Mount option \"%s\" incompatible with ext2", opt);
1819                 return -1;
1820         }
1821         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1822                 ext4_msg(sb, KERN_ERR,
1823                          "Mount option \"%s\" incompatible with ext3", opt);
1824                 return -1;
1825         }
1826
1827         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1828                 return -1;
1829         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1830                 return -1;
1831         if (m->flags & MOPT_EXPLICIT) {
1832                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1833                         set_opt2(sb, EXPLICIT_DELALLOC);
1834                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1835                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1836                 } else
1837                         return -1;
1838         }
1839         if (m->flags & MOPT_CLEAR_ERR)
1840                 clear_opt(sb, ERRORS_MASK);
1841         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1842                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1843                          "options when quota turned on");
1844                 return -1;
1845         }
1846
1847         if (m->flags & MOPT_NOSUPPORT) {
1848                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1849         } else if (token == Opt_commit) {
1850                 if (arg == 0)
1851                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1852                 sbi->s_commit_interval = HZ * arg;
1853         } else if (token == Opt_debug_want_extra_isize) {
1854                 if ((arg & 1) ||
1855                     (arg < 4) ||
1856                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
1857                         ext4_msg(sb, KERN_ERR,
1858                                  "Invalid want_extra_isize %d", arg);
1859                         return -1;
1860                 }
1861                 sbi->s_want_extra_isize = arg;
1862         } else if (token == Opt_max_batch_time) {
1863                 sbi->s_max_batch_time = arg;
1864         } else if (token == Opt_min_batch_time) {
1865                 sbi->s_min_batch_time = arg;
1866         } else if (token == Opt_inode_readahead_blks) {
1867                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1868                         ext4_msg(sb, KERN_ERR,
1869                                  "EXT4-fs: inode_readahead_blks must be "
1870                                  "0 or a power of 2 smaller than 2^31");
1871                         return -1;
1872                 }
1873                 sbi->s_inode_readahead_blks = arg;
1874         } else if (token == Opt_init_itable) {
1875                 set_opt(sb, INIT_INODE_TABLE);
1876                 if (!args->from)
1877                         arg = EXT4_DEF_LI_WAIT_MULT;
1878                 sbi->s_li_wait_mult = arg;
1879         } else if (token == Opt_max_dir_size_kb) {
1880                 sbi->s_max_dir_size_kb = arg;
1881         } else if (token == Opt_stripe) {
1882                 sbi->s_stripe = arg;
1883         } else if (token == Opt_resuid) {
1884                 uid = make_kuid(current_user_ns(), arg);
1885                 if (!uid_valid(uid)) {
1886                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1887                         return -1;
1888                 }
1889                 sbi->s_resuid = uid;
1890         } else if (token == Opt_resgid) {
1891                 gid = make_kgid(current_user_ns(), arg);
1892                 if (!gid_valid(gid)) {
1893                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1894                         return -1;
1895                 }
1896                 sbi->s_resgid = gid;
1897         } else if (token == Opt_journal_dev) {
1898                 if (is_remount) {
1899                         ext4_msg(sb, KERN_ERR,
1900                                  "Cannot specify journal on remount");
1901                         return -1;
1902                 }
1903                 *journal_devnum = arg;
1904         } else if (token == Opt_journal_path) {
1905                 char *journal_path;
1906                 struct inode *journal_inode;
1907                 struct path path;
1908                 int error;
1909
1910                 if (is_remount) {
1911                         ext4_msg(sb, KERN_ERR,
1912                                  "Cannot specify journal on remount");
1913                         return -1;
1914                 }
1915                 journal_path = match_strdup(&args[0]);
1916                 if (!journal_path) {
1917                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1918                                 "journal device string");
1919                         return -1;
1920                 }
1921
1922                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1923                 if (error) {
1924                         ext4_msg(sb, KERN_ERR, "error: could not find "
1925                                 "journal device path: error %d", error);
1926                         kfree(journal_path);
1927                         return -1;
1928                 }
1929
1930                 journal_inode = d_inode(path.dentry);
1931                 if (!S_ISBLK(journal_inode->i_mode)) {
1932                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1933                                 "is not a block device", journal_path);
1934                         path_put(&path);
1935                         kfree(journal_path);
1936                         return -1;
1937                 }
1938
1939                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1940                 path_put(&path);
1941                 kfree(journal_path);
1942         } else if (token == Opt_journal_ioprio) {
1943                 if (arg > 7) {
1944                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1945                                  " (must be 0-7)");
1946                         return -1;
1947                 }
1948                 *journal_ioprio =
1949                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1950         } else if (token == Opt_test_dummy_encryption) {
1951 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1952                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1953                 ext4_msg(sb, KERN_WARNING,
1954                          "Test dummy encryption mode enabled");
1955 #else
1956                 ext4_msg(sb, KERN_WARNING,
1957                          "Test dummy encryption mount option ignored");
1958 #endif
1959         } else if (m->flags & MOPT_DATAJ) {
1960                 if (is_remount) {
1961                         if (!sbi->s_journal)
1962                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1963                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1964                                 ext4_msg(sb, KERN_ERR,
1965                                          "Cannot change data mode on remount");
1966                                 return -1;
1967                         }
1968                 } else {
1969                         clear_opt(sb, DATA_FLAGS);
1970                         sbi->s_mount_opt |= m->mount_opt;
1971                 }
1972 #ifdef CONFIG_QUOTA
1973         } else if (m->flags & MOPT_QFMT) {
1974                 if (sb_any_quota_loaded(sb) &&
1975                     sbi->s_jquota_fmt != m->mount_opt) {
1976                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1977                                  "quota options when quota turned on");
1978                         return -1;
1979                 }
1980                 if (ext4_has_feature_quota(sb)) {
1981                         ext4_msg(sb, KERN_INFO,
1982                                  "Quota format mount options ignored "
1983                                  "when QUOTA feature is enabled");
1984                         return 1;
1985                 }
1986                 sbi->s_jquota_fmt = m->mount_opt;
1987 #endif
1988         } else if (token == Opt_dax) {
1989 #ifdef CONFIG_FS_DAX
1990                 if (is_remount && test_opt(sb, DAX)) {
1991                         ext4_msg(sb, KERN_ERR, "can't mount with "
1992                                 "both data=journal and dax");
1993                         return -1;
1994                 }
1995                 if (is_remount && !(sbi->s_mount_opt & EXT4_MOUNT_DAX)) {
1996                         ext4_msg(sb, KERN_ERR, "can't change "
1997                                         "dax mount option while remounting");
1998                         return -1;
1999                 }
2000                 ext4_msg(sb, KERN_WARNING,
2001                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2002                         sbi->s_mount_opt |= m->mount_opt;
2003 #else
2004                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2005                 return -1;
2006 #endif
2007         } else if (token == Opt_data_err_abort) {
2008                 sbi->s_mount_opt |= m->mount_opt;
2009         } else if (token == Opt_data_err_ignore) {
2010                 sbi->s_mount_opt &= ~m->mount_opt;
2011         } else {
2012                 if (!args->from)
2013                         arg = 1;
2014                 if (m->flags & MOPT_CLEAR)
2015                         arg = !arg;
2016                 else if (unlikely(!(m->flags & MOPT_SET))) {
2017                         ext4_msg(sb, KERN_WARNING,
2018                                  "buggy handling of option %s", opt);
2019                         WARN_ON(1);
2020                         return -1;
2021                 }
2022                 if (arg != 0)
2023                         sbi->s_mount_opt |= m->mount_opt;
2024                 else
2025                         sbi->s_mount_opt &= ~m->mount_opt;
2026         }
2027         return 1;
2028 }
2029
2030 static int parse_options(char *options, struct super_block *sb,
2031                          unsigned long *journal_devnum,
2032                          unsigned int *journal_ioprio,
2033                          int is_remount)
2034 {
2035         struct ext4_sb_info *sbi = EXT4_SB(sb);
2036         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2037         substring_t args[MAX_OPT_ARGS];
2038         int token;
2039
2040         if (!options)
2041                 return 1;
2042
2043         while ((p = strsep(&options, ",")) != NULL) {
2044                 if (!*p)
2045                         continue;
2046                 /*
2047                  * Initialize args struct so we know whether arg was
2048                  * found; some options take optional arguments.
2049                  */
2050                 args[0].to = args[0].from = NULL;
2051                 token = match_token(p, tokens, args);
2052                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2053                                      journal_ioprio, is_remount) < 0)
2054                         return 0;
2055         }
2056 #ifdef CONFIG_QUOTA
2057         /*
2058          * We do the test below only for project quotas. 'usrquota' and
2059          * 'grpquota' mount options are allowed even without quota feature
2060          * to support legacy quotas in quota files.
2061          */
2062         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2063                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2064                          "Cannot enable project quota enforcement.");
2065                 return 0;
2066         }
2067         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2068         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2069         if (usr_qf_name || grp_qf_name) {
2070                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2071                         clear_opt(sb, USRQUOTA);
2072
2073                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2074                         clear_opt(sb, GRPQUOTA);
2075
2076                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2077                         ext4_msg(sb, KERN_ERR, "old and new quota "
2078                                         "format mixing");
2079                         return 0;
2080                 }
2081
2082                 if (!sbi->s_jquota_fmt) {
2083                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2084                                         "not specified");
2085                         return 0;
2086                 }
2087         }
2088 #endif
2089         if (test_opt(sb, DIOREAD_NOLOCK)) {
2090                 int blocksize =
2091                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2092
2093                 if (blocksize < PAGE_SIZE) {
2094                         ext4_msg(sb, KERN_ERR, "can't mount with "
2095                                  "dioread_nolock if block size != PAGE_SIZE");
2096                         return 0;
2097                 }
2098         }
2099         return 1;
2100 }
2101
2102 static inline void ext4_show_quota_options(struct seq_file *seq,
2103                                            struct super_block *sb)
2104 {
2105 #if defined(CONFIG_QUOTA)
2106         struct ext4_sb_info *sbi = EXT4_SB(sb);
2107         char *usr_qf_name, *grp_qf_name;
2108
2109         if (sbi->s_jquota_fmt) {
2110                 char *fmtname = "";
2111
2112                 switch (sbi->s_jquota_fmt) {
2113                 case QFMT_VFS_OLD:
2114                         fmtname = "vfsold";
2115                         break;
2116                 case QFMT_VFS_V0:
2117                         fmtname = "vfsv0";
2118                         break;
2119                 case QFMT_VFS_V1:
2120                         fmtname = "vfsv1";
2121                         break;
2122                 }
2123                 seq_printf(seq, ",jqfmt=%s", fmtname);
2124         }
2125
2126         rcu_read_lock();
2127         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2128         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2129         if (usr_qf_name)
2130                 seq_show_option(seq, "usrjquota", usr_qf_name);
2131         if (grp_qf_name)
2132                 seq_show_option(seq, "grpjquota", grp_qf_name);
2133         rcu_read_unlock();
2134 #endif
2135 }
2136
2137 static const char *token2str(int token)
2138 {
2139         const struct match_token *t;
2140
2141         for (t = tokens; t->token != Opt_err; t++)
2142                 if (t->token == token && !strchr(t->pattern, '='))
2143                         break;
2144         return t->pattern;
2145 }
2146
2147 /*
2148  * Show an option if
2149  *  - it's set to a non-default value OR
2150  *  - if the per-sb default is different from the global default
2151  */
2152 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2153                               int nodefs)
2154 {
2155         struct ext4_sb_info *sbi = EXT4_SB(sb);
2156         struct ext4_super_block *es = sbi->s_es;
2157         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2158         const struct mount_opts *m;
2159         char sep = nodefs ? '\n' : ',';
2160
2161 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2162 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2163
2164         if (sbi->s_sb_block != 1)
2165                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2166
2167         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2168                 int want_set = m->flags & MOPT_SET;
2169                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2170                     (m->flags & MOPT_CLEAR_ERR))
2171                         continue;
2172                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2173                         continue; /* skip if same as the default */
2174                 if ((want_set &&
2175                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2176                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2177                         continue; /* select Opt_noFoo vs Opt_Foo */
2178                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2179         }
2180
2181         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2182             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2183                 SEQ_OPTS_PRINT("resuid=%u",
2184                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2185         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2186             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2187                 SEQ_OPTS_PRINT("resgid=%u",
2188                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2189         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2190         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2191                 SEQ_OPTS_PUTS("errors=remount-ro");
2192         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2193                 SEQ_OPTS_PUTS("errors=continue");
2194         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2195                 SEQ_OPTS_PUTS("errors=panic");
2196         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2197                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2198         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2199                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2200         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2201                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2202         if (sb->s_flags & SB_I_VERSION)
2203                 SEQ_OPTS_PUTS("i_version");
2204         if (nodefs || sbi->s_stripe)
2205                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2206         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2207                         (sbi->s_mount_opt ^ def_mount_opt)) {
2208                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2209                         SEQ_OPTS_PUTS("data=journal");
2210                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2211                         SEQ_OPTS_PUTS("data=ordered");
2212                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2213                         SEQ_OPTS_PUTS("data=writeback");
2214         }
2215         if (nodefs ||
2216             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2217                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2218                                sbi->s_inode_readahead_blks);
2219
2220         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2221                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2222                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2223         if (nodefs || sbi->s_max_dir_size_kb)
2224                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2225         if (test_opt(sb, DATA_ERR_ABORT))
2226                 SEQ_OPTS_PUTS("data_err=abort");
2227         if (DUMMY_ENCRYPTION_ENABLED(sbi))
2228                 SEQ_OPTS_PUTS("test_dummy_encryption");
2229
2230         ext4_show_quota_options(seq, sb);
2231         return 0;
2232 }
2233
2234 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2235 {
2236         return _ext4_show_options(seq, root->d_sb, 0);
2237 }
2238
2239 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2240 {
2241         struct super_block *sb = seq->private;
2242         int rc;
2243
2244         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2245         rc = _ext4_show_options(seq, sb, 1);
2246         seq_puts(seq, "\n");
2247         return rc;
2248 }
2249
2250 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2251                             int read_only)
2252 {
2253         struct ext4_sb_info *sbi = EXT4_SB(sb);
2254         int err = 0;
2255
2256         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2257                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2258                          "forcing read-only mode");
2259                 err = -EROFS;
2260                 goto done;
2261         }
2262         if (read_only)
2263                 goto done;
2264         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2265                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2266                          "running e2fsck is recommended");
2267         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2268                 ext4_msg(sb, KERN_WARNING,
2269                          "warning: mounting fs with errors, "
2270                          "running e2fsck is recommended");
2271         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2272                  le16_to_cpu(es->s_mnt_count) >=
2273                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2274                 ext4_msg(sb, KERN_WARNING,
2275                          "warning: maximal mount count reached, "
2276                          "running e2fsck is recommended");
2277         else if (le32_to_cpu(es->s_checkinterval) &&
2278                  (ext4_get_tstamp(es, s_lastcheck) +
2279                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2280                 ext4_msg(sb, KERN_WARNING,
2281                          "warning: checktime reached, "
2282                          "running e2fsck is recommended");
2283         if (!sbi->s_journal)
2284                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2285         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2286                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2287         le16_add_cpu(&es->s_mnt_count, 1);
2288         ext4_update_tstamp(es, s_mtime);
2289         if (sbi->s_journal)
2290                 ext4_set_feature_journal_needs_recovery(sb);
2291
2292         err = ext4_commit_super(sb, 1);
2293 done:
2294         if (test_opt(sb, DEBUG))
2295                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2296                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2297                         sb->s_blocksize,
2298                         sbi->s_groups_count,
2299                         EXT4_BLOCKS_PER_GROUP(sb),
2300                         EXT4_INODES_PER_GROUP(sb),
2301                         sbi->s_mount_opt, sbi->s_mount_opt2);
2302
2303         cleancache_init_fs(sb);
2304         return err;
2305 }
2306
2307 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2308 {
2309         struct ext4_sb_info *sbi = EXT4_SB(sb);
2310         struct flex_groups **old_groups, **new_groups;
2311         int size, i, j;
2312
2313         if (!sbi->s_log_groups_per_flex)
2314                 return 0;
2315
2316         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2317         if (size <= sbi->s_flex_groups_allocated)
2318                 return 0;
2319
2320         new_groups = kvzalloc(roundup_pow_of_two(size *
2321                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2322         if (!new_groups) {
2323                 ext4_msg(sb, KERN_ERR,
2324                          "not enough memory for %d flex group pointers", size);
2325                 return -ENOMEM;
2326         }
2327         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2328                 new_groups[i] = kvzalloc(roundup_pow_of_two(
2329                                          sizeof(struct flex_groups)),
2330                                          GFP_KERNEL);
2331                 if (!new_groups[i]) {
2332                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
2333                                 kvfree(new_groups[j]);
2334                         kvfree(new_groups);
2335                         ext4_msg(sb, KERN_ERR,
2336                                  "not enough memory for %d flex groups", size);
2337                         return -ENOMEM;
2338                 }
2339         }
2340         rcu_read_lock();
2341         old_groups = rcu_dereference(sbi->s_flex_groups);
2342         if (old_groups)
2343                 memcpy(new_groups, old_groups,
2344                        (sbi->s_flex_groups_allocated *
2345                         sizeof(struct flex_groups *)));
2346         rcu_read_unlock();
2347         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2348         sbi->s_flex_groups_allocated = size;
2349         if (old_groups)
2350                 ext4_kvfree_array_rcu(old_groups);
2351         return 0;
2352 }
2353
2354 static int ext4_fill_flex_info(struct super_block *sb)
2355 {
2356         struct ext4_sb_info *sbi = EXT4_SB(sb);
2357         struct ext4_group_desc *gdp = NULL;
2358         struct flex_groups *fg;
2359         ext4_group_t flex_group;
2360         int i, err;
2361
2362         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2363         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2364                 sbi->s_log_groups_per_flex = 0;
2365                 return 1;
2366         }
2367
2368         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2369         if (err)
2370                 goto failed;
2371
2372         for (i = 0; i < sbi->s_groups_count; i++) {
2373                 gdp = ext4_get_group_desc(sb, i, NULL);
2374
2375                 flex_group = ext4_flex_group(sbi, i);
2376                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2377                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2378                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2379                              &fg->free_clusters);
2380                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2381         }
2382
2383         return 1;
2384 failed:
2385         return 0;
2386 }
2387
2388 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2389                                    struct ext4_group_desc *gdp)
2390 {
2391         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2392         __u16 crc = 0;
2393         __le32 le_group = cpu_to_le32(block_group);
2394         struct ext4_sb_info *sbi = EXT4_SB(sb);
2395
2396         if (ext4_has_metadata_csum(sbi->s_sb)) {
2397                 /* Use new metadata_csum algorithm */
2398                 __u32 csum32;
2399                 __u16 dummy_csum = 0;
2400
2401                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2402                                      sizeof(le_group));
2403                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2404                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2405                                      sizeof(dummy_csum));
2406                 offset += sizeof(dummy_csum);
2407                 if (offset < sbi->s_desc_size)
2408                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2409                                              sbi->s_desc_size - offset);
2410
2411                 crc = csum32 & 0xFFFF;
2412                 goto out;
2413         }
2414
2415         /* old crc16 code */
2416         if (!ext4_has_feature_gdt_csum(sb))
2417                 return 0;
2418
2419         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2420         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2421         crc = crc16(crc, (__u8 *)gdp, offset);
2422         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2423         /* for checksum of struct ext4_group_desc do the rest...*/
2424         if (ext4_has_feature_64bit(sb) &&
2425             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2426                 crc = crc16(crc, (__u8 *)gdp + offset,
2427                             le16_to_cpu(sbi->s_es->s_desc_size) -
2428                                 offset);
2429
2430 out:
2431         return cpu_to_le16(crc);
2432 }
2433
2434 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2435                                 struct ext4_group_desc *gdp)
2436 {
2437         if (ext4_has_group_desc_csum(sb) &&
2438             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2439                 return 0;
2440
2441         return 1;
2442 }
2443
2444 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2445                               struct ext4_group_desc *gdp)
2446 {
2447         if (!ext4_has_group_desc_csum(sb))
2448                 return;
2449         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2450 }
2451
2452 /* Called at mount-time, super-block is locked */
2453 static int ext4_check_descriptors(struct super_block *sb,
2454                                   ext4_fsblk_t sb_block,
2455                                   ext4_group_t *first_not_zeroed)
2456 {
2457         struct ext4_sb_info *sbi = EXT4_SB(sb);
2458         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2459         ext4_fsblk_t last_block;
2460         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2461         ext4_fsblk_t block_bitmap;
2462         ext4_fsblk_t inode_bitmap;
2463         ext4_fsblk_t inode_table;
2464         int flexbg_flag = 0;
2465         ext4_group_t i, grp = sbi->s_groups_count;
2466
2467         if (ext4_has_feature_flex_bg(sb))
2468                 flexbg_flag = 1;
2469
2470         ext4_debug("Checking group descriptors");
2471
2472         for (i = 0; i < sbi->s_groups_count; i++) {
2473                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2474
2475                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2476                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2477                 else
2478                         last_block = first_block +
2479                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2480
2481                 if ((grp == sbi->s_groups_count) &&
2482                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2483                         grp = i;
2484
2485                 block_bitmap = ext4_block_bitmap(sb, gdp);
2486                 if (block_bitmap == sb_block) {
2487                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2488                                  "Block bitmap for group %u overlaps "
2489                                  "superblock", i);
2490                         if (!sb_rdonly(sb))
2491                                 return 0;
2492                 }
2493                 if (block_bitmap >= sb_block + 1 &&
2494                     block_bitmap <= last_bg_block) {
2495                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2496                                  "Block bitmap for group %u overlaps "
2497                                  "block group descriptors", i);
2498                         if (!sb_rdonly(sb))
2499                                 return 0;
2500                 }
2501                 if (block_bitmap < first_block || block_bitmap > last_block) {
2502                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2503                                "Block bitmap for group %u not in group "
2504                                "(block %llu)!", i, block_bitmap);
2505                         return 0;
2506                 }
2507                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2508                 if (inode_bitmap == sb_block) {
2509                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2510                                  "Inode bitmap for group %u overlaps "
2511                                  "superblock", i);
2512                         if (!sb_rdonly(sb))
2513                                 return 0;
2514                 }
2515                 if (inode_bitmap >= sb_block + 1 &&
2516                     inode_bitmap <= last_bg_block) {
2517                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2518                                  "Inode bitmap for group %u overlaps "
2519                                  "block group descriptors", i);
2520                         if (!sb_rdonly(sb))
2521                                 return 0;
2522                 }
2523                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2524                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2525                                "Inode bitmap for group %u not in group "
2526                                "(block %llu)!", i, inode_bitmap);
2527                         return 0;
2528                 }
2529                 inode_table = ext4_inode_table(sb, gdp);
2530                 if (inode_table == sb_block) {
2531                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2532                                  "Inode table for group %u overlaps "
2533                                  "superblock", i);
2534                         if (!sb_rdonly(sb))
2535                                 return 0;
2536                 }
2537                 if (inode_table >= sb_block + 1 &&
2538                     inode_table <= last_bg_block) {
2539                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2540                                  "Inode table for group %u overlaps "
2541                                  "block group descriptors", i);
2542                         if (!sb_rdonly(sb))
2543                                 return 0;
2544                 }
2545                 if (inode_table < first_block ||
2546                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2547                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2548                                "Inode table for group %u not in group "
2549                                "(block %llu)!", i, inode_table);
2550                         return 0;
2551                 }
2552                 ext4_lock_group(sb, i);
2553                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2554                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2555                                  "Checksum for group %u failed (%u!=%u)",
2556                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2557                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2558                         if (!sb_rdonly(sb)) {
2559                                 ext4_unlock_group(sb, i);
2560                                 return 0;
2561                         }
2562                 }
2563                 ext4_unlock_group(sb, i);
2564                 if (!flexbg_flag)
2565                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2566         }
2567         if (NULL != first_not_zeroed)
2568                 *first_not_zeroed = grp;
2569         return 1;
2570 }
2571
2572 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2573  * the superblock) which were deleted from all directories, but held open by
2574  * a process at the time of a crash.  We walk the list and try to delete these
2575  * inodes at recovery time (only with a read-write filesystem).
2576  *
2577  * In order to keep the orphan inode chain consistent during traversal (in
2578  * case of crash during recovery), we link each inode into the superblock
2579  * orphan list_head and handle it the same way as an inode deletion during
2580  * normal operation (which journals the operations for us).
2581  *
2582  * We only do an iget() and an iput() on each inode, which is very safe if we
2583  * accidentally point at an in-use or already deleted inode.  The worst that
2584  * can happen in this case is that we get a "bit already cleared" message from
2585  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2586  * e2fsck was run on this filesystem, and it must have already done the orphan
2587  * inode cleanup for us, so we can safely abort without any further action.
2588  */
2589 static void ext4_orphan_cleanup(struct super_block *sb,
2590                                 struct ext4_super_block *es)
2591 {
2592         unsigned int s_flags = sb->s_flags;
2593         int ret, nr_orphans = 0, nr_truncates = 0;
2594 #ifdef CONFIG_QUOTA
2595         int quota_update = 0;
2596         int i;
2597 #endif
2598         if (!es->s_last_orphan) {
2599                 jbd_debug(4, "no orphan inodes to clean up\n");
2600                 return;
2601         }
2602
2603         if (bdev_read_only(sb->s_bdev)) {
2604                 ext4_msg(sb, KERN_ERR, "write access "
2605                         "unavailable, skipping orphan cleanup");
2606                 return;
2607         }
2608
2609         /* Check if feature set would not allow a r/w mount */
2610         if (!ext4_feature_set_ok(sb, 0)) {
2611                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2612                          "unknown ROCOMPAT features");
2613                 return;
2614         }
2615
2616         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2617                 /* don't clear list on RO mount w/ errors */
2618                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2619                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2620                                   "clearing orphan list.\n");
2621                         es->s_last_orphan = 0;
2622                 }
2623                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2624                 return;
2625         }
2626
2627         if (s_flags & SB_RDONLY) {
2628                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2629                 sb->s_flags &= ~SB_RDONLY;
2630         }
2631 #ifdef CONFIG_QUOTA
2632         /*
2633          * Turn on quotas which were not enabled for read-only mounts if
2634          * filesystem has quota feature, so that they are updated correctly.
2635          */
2636         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2637                 int ret = ext4_enable_quotas(sb);
2638
2639                 if (!ret)
2640                         quota_update = 1;
2641                 else
2642                         ext4_msg(sb, KERN_ERR,
2643                                 "Cannot turn on quotas: error %d", ret);
2644         }
2645
2646         /* Turn on journaled quotas used for old sytle */
2647         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2648                 if (EXT4_SB(sb)->s_qf_names[i]) {
2649                         int ret = ext4_quota_on_mount(sb, i);
2650
2651                         if (!ret)
2652                                 quota_update = 1;
2653                         else
2654                                 ext4_msg(sb, KERN_ERR,
2655                                         "Cannot turn on journaled "
2656                                         "quota: type %d: error %d", i, ret);
2657                 }
2658         }
2659 #endif
2660
2661         while (es->s_last_orphan) {
2662                 struct inode *inode;
2663
2664                 /*
2665                  * We may have encountered an error during cleanup; if
2666                  * so, skip the rest.
2667                  */
2668                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2669                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2670                         es->s_last_orphan = 0;
2671                         break;
2672                 }
2673
2674                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2675                 if (IS_ERR(inode)) {
2676                         es->s_last_orphan = 0;
2677                         break;
2678                 }
2679
2680                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2681                 dquot_initialize(inode);
2682                 if (inode->i_nlink) {
2683                         if (test_opt(sb, DEBUG))
2684                                 ext4_msg(sb, KERN_DEBUG,
2685                                         "%s: truncating inode %lu to %lld bytes",
2686                                         __func__, inode->i_ino, inode->i_size);
2687                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2688                                   inode->i_ino, inode->i_size);
2689                         inode_lock(inode);
2690                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2691                         ret = ext4_truncate(inode);
2692                         if (ret) {
2693                                 /*
2694                                  * We need to clean up the in-core orphan list
2695                                  * manually if ext4_truncate() failed to get a
2696                                  * transaction handle.
2697                                  */
2698                                 ext4_orphan_del(NULL, inode);
2699                                 ext4_std_error(inode->i_sb, ret);
2700                         }
2701                         inode_unlock(inode);
2702                         nr_truncates++;
2703                 } else {
2704                         if (test_opt(sb, DEBUG))
2705                                 ext4_msg(sb, KERN_DEBUG,
2706                                         "%s: deleting unreferenced inode %lu",
2707                                         __func__, inode->i_ino);
2708                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2709                                   inode->i_ino);
2710                         nr_orphans++;
2711                 }
2712                 iput(inode);  /* The delete magic happens here! */
2713         }
2714
2715 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2716
2717         if (nr_orphans)
2718                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2719                        PLURAL(nr_orphans));
2720         if (nr_truncates)
2721                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2722                        PLURAL(nr_truncates));
2723 #ifdef CONFIG_QUOTA
2724         /* Turn off quotas if they were enabled for orphan cleanup */
2725         if (quota_update) {
2726                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2727                         if (sb_dqopt(sb)->files[i])
2728                                 dquot_quota_off(sb, i);
2729                 }
2730         }
2731 #endif
2732         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2733 }
2734
2735 /*
2736  * Maximal extent format file size.
2737  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2738  * extent format containers, within a sector_t, and within i_blocks
2739  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2740  * so that won't be a limiting factor.
2741  *
2742  * However there is other limiting factor. We do store extents in the form
2743  * of starting block and length, hence the resulting length of the extent
2744  * covering maximum file size must fit into on-disk format containers as
2745  * well. Given that length is always by 1 unit bigger than max unit (because
2746  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2747  *
2748  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2749  */
2750 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2751 {
2752         loff_t res;
2753         loff_t upper_limit = MAX_LFS_FILESIZE;
2754
2755         /* small i_blocks in vfs inode? */
2756         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2757                 /*
2758                  * CONFIG_LBDAF is not enabled implies the inode
2759                  * i_block represent total blocks in 512 bytes
2760                  * 32 == 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 >>= (blkbits - 9);
2766                 upper_limit <<= blkbits;
2767         }
2768
2769         /*
2770          * 32-bit extent-start container, ee_block. We lower the maxbytes
2771          * by one fs block, so ee_len can cover the extent of maximum file
2772          * size
2773          */
2774         res = (1LL << 32) - 1;
2775         res <<= blkbits;
2776
2777         /* Sanity check against vm- & vfs- imposed limits */
2778         if (res > upper_limit)
2779                 res = upper_limit;
2780
2781         return res;
2782 }
2783
2784 /*
2785  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2786  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2787  * We need to be 1 filesystem block less than the 2^48 sector limit.
2788  */
2789 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2790 {
2791         loff_t res = EXT4_NDIR_BLOCKS;
2792         int meta_blocks;
2793         loff_t upper_limit;
2794         /* This is calculated to be the largest file size for a dense, block
2795          * mapped file such that the file's total number of 512-byte sectors,
2796          * including data and all indirect blocks, does not exceed (2^48 - 1).
2797          *
2798          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2799          * number of 512-byte sectors of the file.
2800          */
2801
2802         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2803                 /*
2804                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2805                  * the inode i_block field represents total file blocks in
2806                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2807                  */
2808                 upper_limit = (1LL << 32) - 1;
2809
2810                 /* total blocks in file system block size */
2811                 upper_limit >>= (bits - 9);
2812
2813         } else {
2814                 /*
2815                  * We use 48 bit ext4_inode i_blocks
2816                  * With EXT4_HUGE_FILE_FL set the i_blocks
2817                  * represent total number of blocks in
2818                  * file system block size
2819                  */
2820                 upper_limit = (1LL << 48) - 1;
2821
2822         }
2823
2824         /* indirect blocks */
2825         meta_blocks = 1;
2826         /* double indirect blocks */
2827         meta_blocks += 1 + (1LL << (bits-2));
2828         /* tripple indirect blocks */
2829         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2830
2831         upper_limit -= meta_blocks;
2832         upper_limit <<= bits;
2833
2834         res += 1LL << (bits-2);
2835         res += 1LL << (2*(bits-2));
2836         res += 1LL << (3*(bits-2));
2837         res <<= bits;
2838         if (res > upper_limit)
2839                 res = upper_limit;
2840
2841         if (res > MAX_LFS_FILESIZE)
2842                 res = MAX_LFS_FILESIZE;
2843
2844         return res;
2845 }
2846
2847 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2848                                    ext4_fsblk_t logical_sb_block, int nr)
2849 {
2850         struct ext4_sb_info *sbi = EXT4_SB(sb);
2851         ext4_group_t bg, first_meta_bg;
2852         int has_super = 0;
2853
2854         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2855
2856         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2857                 return logical_sb_block + nr + 1;
2858         bg = sbi->s_desc_per_block * nr;
2859         if (ext4_bg_has_super(sb, bg))
2860                 has_super = 1;
2861
2862         /*
2863          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2864          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2865          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2866          * compensate.
2867          */
2868         if (sb->s_blocksize == 1024 && nr == 0 &&
2869             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
2870                 has_super++;
2871
2872         return (has_super + ext4_group_first_block_no(sb, bg));
2873 }
2874
2875 /**
2876  * ext4_get_stripe_size: Get the stripe size.
2877  * @sbi: In memory super block info
2878  *
2879  * If we have specified it via mount option, then
2880  * use the mount option value. If the value specified at mount time is
2881  * greater than the blocks per group use the super block value.
2882  * If the super block value is greater than blocks per group return 0.
2883  * Allocator needs it be less than blocks per group.
2884  *
2885  */
2886 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2887 {
2888         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2889         unsigned long stripe_width =
2890                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2891         int ret;
2892
2893         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2894                 ret = sbi->s_stripe;
2895         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2896                 ret = stripe_width;
2897         else if (stride && stride <= sbi->s_blocks_per_group)
2898                 ret = stride;
2899         else
2900                 ret = 0;
2901
2902         /*
2903          * If the stripe width is 1, this makes no sense and
2904          * we set it to 0 to turn off stripe handling code.
2905          */
2906         if (ret <= 1)
2907                 ret = 0;
2908
2909         return ret;
2910 }
2911
2912 /*
2913  * Check whether this filesystem can be mounted based on
2914  * the features present and the RDONLY/RDWR mount requested.
2915  * Returns 1 if this filesystem can be mounted as requested,
2916  * 0 if it cannot be.
2917  */
2918 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2919 {
2920         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2921                 ext4_msg(sb, KERN_ERR,
2922                         "Couldn't mount because of "
2923                         "unsupported optional features (%x)",
2924                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2925                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2926                 return 0;
2927         }
2928
2929         if (readonly)
2930                 return 1;
2931
2932         if (ext4_has_feature_readonly(sb)) {
2933                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2934                 sb->s_flags |= SB_RDONLY;
2935                 return 1;
2936         }
2937
2938         /* Check that feature set is OK for a read-write mount */
2939         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2940                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2941                          "unsupported optional features (%x)",
2942                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2943                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2944                 return 0;
2945         }
2946         /*
2947          * Large file size enabled file system can only be mounted
2948          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2949          */
2950         if (ext4_has_feature_huge_file(sb)) {
2951                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2952                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2953                                  "cannot be mounted RDWR without "
2954                                  "CONFIG_LBDAF");
2955                         return 0;
2956                 }
2957         }
2958         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2959                 ext4_msg(sb, KERN_ERR,
2960                          "Can't support bigalloc feature without "
2961                          "extents feature\n");
2962                 return 0;
2963         }
2964
2965 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
2966         if (!readonly && (ext4_has_feature_quota(sb) ||
2967                           ext4_has_feature_project(sb))) {
2968                 ext4_msg(sb, KERN_ERR,
2969                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
2970                 return 0;
2971         }
2972 #endif  /* CONFIG_QUOTA */
2973         return 1;
2974 }
2975
2976 /*
2977  * This function is called once a day if we have errors logged
2978  * on the file system
2979  */
2980 static void print_daily_error_info(struct timer_list *t)
2981 {
2982         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
2983         struct super_block *sb = sbi->s_sb;
2984         struct ext4_super_block *es = sbi->s_es;
2985
2986         if (es->s_error_count)
2987                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2988                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2989                          le32_to_cpu(es->s_error_count));
2990         if (es->s_first_error_time) {
2991                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
2992                        sb->s_id,
2993                        ext4_get_tstamp(es, s_first_error_time),
2994                        (int) sizeof(es->s_first_error_func),
2995                        es->s_first_error_func,
2996                        le32_to_cpu(es->s_first_error_line));
2997                 if (es->s_first_error_ino)
2998                         printk(KERN_CONT ": inode %u",
2999                                le32_to_cpu(es->s_first_error_ino));
3000                 if (es->s_first_error_block)
3001                         printk(KERN_CONT ": block %llu", (unsigned long long)
3002                                le64_to_cpu(es->s_first_error_block));
3003                 printk(KERN_CONT "\n");
3004         }
3005         if (es->s_last_error_time) {
3006                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3007                        sb->s_id,
3008                        ext4_get_tstamp(es, s_last_error_time),
3009                        (int) sizeof(es->s_last_error_func),
3010                        es->s_last_error_func,
3011                        le32_to_cpu(es->s_last_error_line));
3012                 if (es->s_last_error_ino)
3013                         printk(KERN_CONT ": inode %u",
3014                                le32_to_cpu(es->s_last_error_ino));
3015                 if (es->s_last_error_block)
3016                         printk(KERN_CONT ": block %llu", (unsigned long long)
3017                                le64_to_cpu(es->s_last_error_block));
3018                 printk(KERN_CONT "\n");
3019         }
3020         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3021 }
3022
3023 /* Find next suitable group and run ext4_init_inode_table */
3024 static int ext4_run_li_request(struct ext4_li_request *elr)
3025 {
3026         struct ext4_group_desc *gdp = NULL;
3027         ext4_group_t group, ngroups;
3028         struct super_block *sb;
3029         int ret = 0;
3030         u64 start_time;
3031
3032         sb = elr->lr_super;
3033         ngroups = EXT4_SB(sb)->s_groups_count;
3034
3035         for (group = elr->lr_next_group; group < ngroups; group++) {
3036                 gdp = ext4_get_group_desc(sb, group, NULL);
3037                 if (!gdp) {
3038                         ret = 1;
3039                         break;
3040                 }
3041
3042                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3043                         break;
3044         }
3045
3046         if (group >= ngroups)
3047                 ret = 1;
3048
3049         if (!ret) {
3050                 start_time = ktime_get_real_ns();
3051                 ret = ext4_init_inode_table(sb, group,
3052                                             elr->lr_timeout ? 0 : 1);
3053                 if (elr->lr_timeout == 0) {
3054                         elr->lr_timeout = nsecs_to_jiffies((ktime_get_real_ns() - start_time) *
3055                                   elr->lr_sbi->s_li_wait_mult);
3056                 }
3057                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3058                 elr->lr_next_group = group + 1;
3059         }
3060         return ret;
3061 }
3062
3063 /*
3064  * Remove lr_request from the list_request and free the
3065  * request structure. Should be called with li_list_mtx held
3066  */
3067 static void ext4_remove_li_request(struct ext4_li_request *elr)
3068 {
3069         struct ext4_sb_info *sbi;
3070
3071         if (!elr)
3072                 return;
3073
3074         sbi = elr->lr_sbi;
3075
3076         list_del(&elr->lr_request);
3077         sbi->s_li_request = NULL;
3078         kfree(elr);
3079 }
3080
3081 static void ext4_unregister_li_request(struct super_block *sb)
3082 {
3083         mutex_lock(&ext4_li_mtx);
3084         if (!ext4_li_info) {
3085                 mutex_unlock(&ext4_li_mtx);
3086                 return;
3087         }
3088
3089         mutex_lock(&ext4_li_info->li_list_mtx);
3090         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3091         mutex_unlock(&ext4_li_info->li_list_mtx);
3092         mutex_unlock(&ext4_li_mtx);
3093 }
3094
3095 static struct task_struct *ext4_lazyinit_task;
3096
3097 /*
3098  * This is the function where ext4lazyinit thread lives. It walks
3099  * through the request list searching for next scheduled filesystem.
3100  * When such a fs is found, run the lazy initialization request
3101  * (ext4_rn_li_request) and keep track of the time spend in this
3102  * function. Based on that time we compute next schedule time of
3103  * the request. When walking through the list is complete, compute
3104  * next waking time and put itself into sleep.
3105  */
3106 static int ext4_lazyinit_thread(void *arg)
3107 {
3108         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3109         struct list_head *pos, *n;
3110         struct ext4_li_request *elr;
3111         unsigned long next_wakeup, cur;
3112
3113         BUG_ON(NULL == eli);
3114
3115 cont_thread:
3116         while (true) {
3117                 next_wakeup = MAX_JIFFY_OFFSET;
3118
3119                 mutex_lock(&eli->li_list_mtx);
3120                 if (list_empty(&eli->li_request_list)) {
3121                         mutex_unlock(&eli->li_list_mtx);
3122                         goto exit_thread;
3123                 }
3124                 list_for_each_safe(pos, n, &eli->li_request_list) {
3125                         int err = 0;
3126                         int progress = 0;
3127                         elr = list_entry(pos, struct ext4_li_request,
3128                                          lr_request);
3129
3130                         if (time_before(jiffies, elr->lr_next_sched)) {
3131                                 if (time_before(elr->lr_next_sched, next_wakeup))
3132                                         next_wakeup = elr->lr_next_sched;
3133                                 continue;
3134                         }
3135                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3136                                 if (sb_start_write_trylock(elr->lr_super)) {
3137                                         progress = 1;
3138                                         /*
3139                                          * We hold sb->s_umount, sb can not
3140                                          * be removed from the list, it is
3141                                          * now safe to drop li_list_mtx
3142                                          */
3143                                         mutex_unlock(&eli->li_list_mtx);
3144                                         err = ext4_run_li_request(elr);
3145                                         sb_end_write(elr->lr_super);
3146                                         mutex_lock(&eli->li_list_mtx);
3147                                         n = pos->next;
3148                                 }
3149                                 up_read((&elr->lr_super->s_umount));
3150                         }
3151                         /* error, remove the lazy_init job */
3152                         if (err) {
3153                                 ext4_remove_li_request(elr);
3154                                 continue;
3155                         }
3156                         if (!progress) {
3157                                 elr->lr_next_sched = jiffies +
3158                                         (prandom_u32()
3159                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3160                         }
3161                         if (time_before(elr->lr_next_sched, next_wakeup))
3162                                 next_wakeup = elr->lr_next_sched;
3163                 }
3164                 mutex_unlock(&eli->li_list_mtx);
3165
3166                 try_to_freeze();
3167
3168                 cur = jiffies;
3169                 if ((time_after_eq(cur, next_wakeup)) ||
3170                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3171                         cond_resched();
3172                         continue;
3173                 }
3174
3175                 schedule_timeout_interruptible(next_wakeup - cur);
3176
3177                 if (kthread_should_stop()) {
3178                         ext4_clear_request_list();
3179                         goto exit_thread;
3180                 }
3181         }
3182
3183 exit_thread:
3184         /*
3185          * It looks like the request list is empty, but we need
3186          * to check it under the li_list_mtx lock, to prevent any
3187          * additions into it, and of course we should lock ext4_li_mtx
3188          * to atomically free the list and ext4_li_info, because at
3189          * this point another ext4 filesystem could be registering
3190          * new one.
3191          */
3192         mutex_lock(&ext4_li_mtx);
3193         mutex_lock(&eli->li_list_mtx);
3194         if (!list_empty(&eli->li_request_list)) {
3195                 mutex_unlock(&eli->li_list_mtx);
3196                 mutex_unlock(&ext4_li_mtx);
3197                 goto cont_thread;
3198         }
3199         mutex_unlock(&eli->li_list_mtx);
3200         kfree(ext4_li_info);
3201         ext4_li_info = NULL;
3202         mutex_unlock(&ext4_li_mtx);
3203
3204         return 0;
3205 }
3206
3207 static void ext4_clear_request_list(void)
3208 {
3209         struct list_head *pos, *n;
3210         struct ext4_li_request *elr;
3211
3212         mutex_lock(&ext4_li_info->li_list_mtx);
3213         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3214                 elr = list_entry(pos, struct ext4_li_request,
3215                                  lr_request);
3216                 ext4_remove_li_request(elr);
3217         }
3218         mutex_unlock(&ext4_li_info->li_list_mtx);
3219 }
3220
3221 static int ext4_run_lazyinit_thread(void)
3222 {
3223         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3224                                          ext4_li_info, "ext4lazyinit");
3225         if (IS_ERR(ext4_lazyinit_task)) {
3226                 int err = PTR_ERR(ext4_lazyinit_task);
3227                 ext4_clear_request_list();
3228                 kfree(ext4_li_info);
3229                 ext4_li_info = NULL;
3230                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3231                                  "initialization thread\n",
3232                                  err);
3233                 return err;
3234         }
3235         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3236         return 0;
3237 }
3238
3239 /*
3240  * Check whether it make sense to run itable init. thread or not.
3241  * If there is at least one uninitialized inode table, return
3242  * corresponding group number, else the loop goes through all
3243  * groups and return total number of groups.
3244  */
3245 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3246 {
3247         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3248         struct ext4_group_desc *gdp = NULL;
3249
3250         if (!ext4_has_group_desc_csum(sb))
3251                 return ngroups;
3252
3253         for (group = 0; group < ngroups; group++) {
3254                 gdp = ext4_get_group_desc(sb, group, NULL);
3255                 if (!gdp)
3256                         continue;
3257
3258                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3259                         break;
3260         }
3261
3262         return group;
3263 }
3264
3265 static int ext4_li_info_new(void)
3266 {
3267         struct ext4_lazy_init *eli = NULL;
3268
3269         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3270         if (!eli)
3271                 return -ENOMEM;
3272
3273         INIT_LIST_HEAD(&eli->li_request_list);
3274         mutex_init(&eli->li_list_mtx);
3275
3276         eli->li_state |= EXT4_LAZYINIT_QUIT;
3277
3278         ext4_li_info = eli;
3279
3280         return 0;
3281 }
3282
3283 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3284                                             ext4_group_t start)
3285 {
3286         struct ext4_sb_info *sbi = EXT4_SB(sb);
3287         struct ext4_li_request *elr;
3288
3289         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3290         if (!elr)
3291                 return NULL;
3292
3293         elr->lr_super = sb;
3294         elr->lr_sbi = sbi;
3295         elr->lr_next_group = start;
3296
3297         /*
3298          * Randomize first schedule time of the request to
3299          * spread the inode table initialization requests
3300          * better.
3301          */
3302         elr->lr_next_sched = jiffies + (prandom_u32() %
3303                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3304         return elr;
3305 }
3306
3307 int ext4_register_li_request(struct super_block *sb,
3308                              ext4_group_t first_not_zeroed)
3309 {
3310         struct ext4_sb_info *sbi = EXT4_SB(sb);
3311         struct ext4_li_request *elr = NULL;
3312         ext4_group_t ngroups = sbi->s_groups_count;
3313         int ret = 0;
3314
3315         mutex_lock(&ext4_li_mtx);
3316         if (sbi->s_li_request != NULL) {
3317                 /*
3318                  * Reset timeout so it can be computed again, because
3319                  * s_li_wait_mult might have changed.
3320                  */
3321                 sbi->s_li_request->lr_timeout = 0;
3322                 goto out;
3323         }
3324
3325         if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3326             !test_opt(sb, INIT_INODE_TABLE))
3327                 goto out;
3328
3329         elr = ext4_li_request_new(sb, first_not_zeroed);
3330         if (!elr) {
3331                 ret = -ENOMEM;
3332                 goto out;
3333         }
3334
3335         if (NULL == ext4_li_info) {
3336                 ret = ext4_li_info_new();
3337                 if (ret)
3338                         goto out;
3339         }
3340
3341         mutex_lock(&ext4_li_info->li_list_mtx);
3342         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3343         mutex_unlock(&ext4_li_info->li_list_mtx);
3344
3345         sbi->s_li_request = elr;
3346         /*
3347          * set elr to NULL here since it has been inserted to
3348          * the request_list and the removal and free of it is
3349          * handled by ext4_clear_request_list from now on.
3350          */
3351         elr = NULL;
3352
3353         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3354                 ret = ext4_run_lazyinit_thread();
3355                 if (ret)
3356                         goto out;
3357         }
3358 out:
3359         mutex_unlock(&ext4_li_mtx);
3360         if (ret)
3361                 kfree(elr);
3362         return ret;
3363 }
3364
3365 /*
3366  * We do not need to lock anything since this is called on
3367  * module unload.
3368  */
3369 static void ext4_destroy_lazyinit_thread(void)
3370 {
3371         /*
3372          * If thread exited earlier
3373          * there's nothing to be done.
3374          */
3375         if (!ext4_li_info || !ext4_lazyinit_task)
3376                 return;
3377
3378         kthread_stop(ext4_lazyinit_task);
3379 }
3380
3381 static int set_journal_csum_feature_set(struct super_block *sb)
3382 {
3383         int ret = 1;
3384         int compat, incompat;
3385         struct ext4_sb_info *sbi = EXT4_SB(sb);
3386
3387         if (ext4_has_metadata_csum(sb)) {
3388                 /* journal checksum v3 */
3389                 compat = 0;
3390                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3391         } else {
3392                 /* journal checksum v1 */
3393                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3394                 incompat = 0;
3395         }
3396
3397         jbd2_journal_clear_features(sbi->s_journal,
3398                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3399                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3400                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3401         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3402                 ret = jbd2_journal_set_features(sbi->s_journal,
3403                                 compat, 0,
3404                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3405                                 incompat);
3406         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3407                 ret = jbd2_journal_set_features(sbi->s_journal,
3408                                 compat, 0,
3409                                 incompat);
3410                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3411                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3412         } else {
3413                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3414                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3415         }
3416
3417         return ret;
3418 }
3419
3420 /*
3421  * Note: calculating the overhead so we can be compatible with
3422  * historical BSD practice is quite difficult in the face of
3423  * clusters/bigalloc.  This is because multiple metadata blocks from
3424  * different block group can end up in the same allocation cluster.
3425  * Calculating the exact overhead in the face of clustered allocation
3426  * requires either O(all block bitmaps) in memory or O(number of block
3427  * groups**2) in time.  We will still calculate the superblock for
3428  * older file systems --- and if we come across with a bigalloc file
3429  * system with zero in s_overhead_clusters the estimate will be close to
3430  * correct especially for very large cluster sizes --- but for newer
3431  * file systems, it's better to calculate this figure once at mkfs
3432  * time, and store it in the superblock.  If the superblock value is
3433  * present (even for non-bigalloc file systems), we will use it.
3434  */
3435 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3436                           char *buf)
3437 {
3438         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3439         struct ext4_group_desc  *gdp;
3440         ext4_fsblk_t            first_block, last_block, b;
3441         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3442         int                     s, j, count = 0;
3443         int                     has_super = ext4_bg_has_super(sb, grp);
3444
3445         if (!ext4_has_feature_bigalloc(sb))
3446                 return (has_super + ext4_bg_num_gdb(sb, grp) +
3447                         (has_super ? le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0) +
3448                         sbi->s_itb_per_group + 2);
3449
3450         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3451                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3452         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3453         for (i = 0; i < ngroups; i++) {
3454                 gdp = ext4_get_group_desc(sb, i, NULL);
3455                 b = ext4_block_bitmap(sb, gdp);
3456                 if (b >= first_block && b <= last_block) {
3457                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3458                         count++;
3459                 }
3460                 b = ext4_inode_bitmap(sb, gdp);
3461                 if (b >= first_block && b <= last_block) {
3462                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3463                         count++;
3464                 }
3465                 b = ext4_inode_table(sb, gdp);
3466                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3467                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3468                                 int c = EXT4_B2C(sbi, b - first_block);
3469                                 ext4_set_bit(c, buf);
3470                                 count++;
3471                         }
3472                 if (i != grp)
3473                         continue;
3474                 s = 0;
3475                 if (ext4_bg_has_super(sb, grp)) {
3476                         ext4_set_bit(s++, buf);
3477                         count++;
3478                 }
3479                 j = ext4_bg_num_gdb(sb, grp);
3480                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3481                         ext4_error(sb, "Invalid number of block group "
3482                                    "descriptor blocks: %d", j);
3483                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3484                 }
3485                 count += j;
3486                 for (; j > 0; j--)
3487                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3488         }
3489         if (!count)
3490                 return 0;
3491         return EXT4_CLUSTERS_PER_GROUP(sb) -
3492                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3493 }
3494
3495 /*
3496  * Compute the overhead and stash it in sbi->s_overhead
3497  */
3498 int ext4_calculate_overhead(struct super_block *sb)
3499 {
3500         struct ext4_sb_info *sbi = EXT4_SB(sb);
3501         struct ext4_super_block *es = sbi->s_es;
3502         struct inode *j_inode;
3503         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3504         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3505         ext4_fsblk_t overhead = 0;
3506         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3507
3508         if (!buf)
3509                 return -ENOMEM;
3510
3511         /*
3512          * Compute the overhead (FS structures).  This is constant
3513          * for a given filesystem unless the number of block groups
3514          * changes so we cache the previous value until it does.
3515          */
3516
3517         /*
3518          * All of the blocks before first_data_block are overhead
3519          */
3520         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3521
3522         /*
3523          * Add the overhead found in each block group
3524          */
3525         for (i = 0; i < ngroups; i++) {
3526                 int blks;
3527
3528                 blks = count_overhead(sb, i, buf);
3529                 overhead += blks;
3530                 if (blks)
3531                         memset(buf, 0, PAGE_SIZE);
3532                 cond_resched();
3533         }
3534
3535         /*
3536          * Add the internal journal blocks whether the journal has been
3537          * loaded or not
3538          */
3539         if (sbi->s_journal && !sbi->journal_bdev)
3540                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3541         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3542                 /* j_inum for internal journal is non-zero */
3543                 j_inode = ext4_get_journal_inode(sb, j_inum);
3544                 if (j_inode) {
3545                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3546                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3547                         iput(j_inode);
3548                 } else {
3549                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3550                 }
3551         }
3552         sbi->s_overhead = overhead;
3553         smp_wmb();
3554         free_page((unsigned long) buf);
3555         return 0;
3556 }
3557
3558 static void ext4_set_resv_clusters(struct super_block *sb)
3559 {
3560         ext4_fsblk_t resv_clusters;
3561         struct ext4_sb_info *sbi = EXT4_SB(sb);
3562
3563         /*
3564          * There's no need to reserve anything when we aren't using extents.
3565          * The space estimates are exact, there are no unwritten extents,
3566          * hole punching doesn't need new metadata... This is needed especially
3567          * to keep ext2/3 backward compatibility.
3568          */
3569         if (!ext4_has_feature_extents(sb))
3570                 return;
3571         /*
3572          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3573          * This should cover the situations where we can not afford to run
3574          * out of space like for example punch hole, or converting
3575          * unwritten extents in delalloc path. In most cases such
3576          * allocation would require 1, or 2 blocks, higher numbers are
3577          * very rare.
3578          */
3579         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3580                          sbi->s_cluster_bits);
3581
3582         do_div(resv_clusters, 50);
3583         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3584
3585         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3586 }
3587
3588 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3589 {
3590         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3591         char *orig_data = kstrdup(data, GFP_KERNEL);
3592         struct buffer_head *bh, **group_desc;
3593         struct ext4_super_block *es = NULL;
3594         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3595         struct flex_groups **flex_groups;
3596         ext4_fsblk_t block;
3597         ext4_fsblk_t sb_block = get_sb_block(&data);
3598         ext4_fsblk_t logical_sb_block;
3599         unsigned long offset = 0;
3600         unsigned long journal_devnum = 0;
3601         unsigned long def_mount_opts;
3602         struct inode *root;
3603         const char *descr;
3604         int ret = -ENOMEM;
3605         int blocksize, clustersize;
3606         unsigned int db_count;
3607         unsigned int i;
3608         int needs_recovery, has_huge_files, has_bigalloc;
3609         __u64 blocks_count;
3610         int err = 0;
3611         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3612         ext4_group_t first_not_zeroed;
3613
3614         if ((data && !orig_data) || !sbi)
3615                 goto out_free_base;
3616
3617         sbi->s_daxdev = dax_dev;
3618         sbi->s_blockgroup_lock =
3619                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3620         if (!sbi->s_blockgroup_lock)
3621                 goto out_free_base;
3622
3623         sb->s_fs_info = sbi;
3624         sbi->s_sb = sb;
3625         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3626         sbi->s_sb_block = sb_block;
3627         if (sb->s_bdev->bd_part)
3628                 sbi->s_sectors_written_start =
3629                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
3630
3631         /* Cleanup superblock name */
3632         strreplace(sb->s_id, '/', '!');
3633
3634         /* -EINVAL is default */
3635         ret = -EINVAL;
3636         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3637         if (!blocksize) {
3638                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3639                 goto out_fail;
3640         }
3641
3642         /*
3643          * The ext4 superblock will not be buffer aligned for other than 1kB
3644          * block sizes.  We need to calculate the offset from buffer start.
3645          */
3646         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3647                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3648                 offset = do_div(logical_sb_block, blocksize);
3649         } else {
3650                 logical_sb_block = sb_block;
3651         }
3652
3653         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3654                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3655                 goto out_fail;
3656         }
3657         /*
3658          * Note: s_es must be initialized as soon as possible because
3659          *       some ext4 macro-instructions depend on its value
3660          */
3661         es = (struct ext4_super_block *) (bh->b_data + offset);
3662         sbi->s_es = es;
3663         sb->s_magic = le16_to_cpu(es->s_magic);
3664         if (sb->s_magic != EXT4_SUPER_MAGIC)
3665                 goto cantfind_ext4;
3666         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3667
3668         /* Warn if metadata_csum and gdt_csum are both set. */
3669         if (ext4_has_feature_metadata_csum(sb) &&
3670             ext4_has_feature_gdt_csum(sb))
3671                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3672                              "redundant flags; please run fsck.");
3673
3674         /* Check for a known checksum algorithm */
3675         if (!ext4_verify_csum_type(sb, es)) {
3676                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3677                          "unknown checksum algorithm.");
3678                 silent = 1;
3679                 goto cantfind_ext4;
3680         }
3681
3682         /* Load the checksum driver */
3683         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3684         if (IS_ERR(sbi->s_chksum_driver)) {
3685                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3686                 ret = PTR_ERR(sbi->s_chksum_driver);
3687                 sbi->s_chksum_driver = NULL;
3688                 goto failed_mount;
3689         }
3690
3691         /* Check superblock checksum */
3692         if (!ext4_superblock_csum_verify(sb, es)) {
3693                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3694                          "invalid superblock checksum.  Run e2fsck?");
3695                 silent = 1;
3696                 ret = -EFSBADCRC;
3697                 goto cantfind_ext4;
3698         }
3699
3700         /* Precompute checksum seed for all metadata */
3701         if (ext4_has_feature_csum_seed(sb))
3702                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3703         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3704                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3705                                                sizeof(es->s_uuid));
3706
3707         /* Set defaults before we parse the mount options */
3708         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3709         set_opt(sb, INIT_INODE_TABLE);
3710         if (def_mount_opts & EXT4_DEFM_DEBUG)
3711                 set_opt(sb, DEBUG);
3712         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3713                 set_opt(sb, GRPID);
3714         if (def_mount_opts & EXT4_DEFM_UID16)
3715                 set_opt(sb, NO_UID32);
3716         /* xattr user namespace & acls are now defaulted on */
3717         set_opt(sb, XATTR_USER);
3718 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3719         set_opt(sb, POSIX_ACL);
3720 #endif
3721         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3722         if (ext4_has_metadata_csum(sb))
3723                 set_opt(sb, JOURNAL_CHECKSUM);
3724
3725         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3726                 set_opt(sb, JOURNAL_DATA);
3727         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3728                 set_opt(sb, ORDERED_DATA);
3729         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3730                 set_opt(sb, WRITEBACK_DATA);
3731
3732         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3733                 set_opt(sb, ERRORS_PANIC);
3734         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3735                 set_opt(sb, ERRORS_CONT);
3736         else
3737                 set_opt(sb, ERRORS_RO);
3738         /* block_validity enabled by default; disable with noblock_validity */
3739         set_opt(sb, BLOCK_VALIDITY);
3740         if (def_mount_opts & EXT4_DEFM_DISCARD)
3741                 set_opt(sb, DISCARD);
3742
3743         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3744         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3745         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3746         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3747         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3748
3749         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3750                 set_opt(sb, BARRIER);
3751
3752         /*
3753          * enable delayed allocation by default
3754          * Use -o nodelalloc to turn it off
3755          */
3756         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3757             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3758                 set_opt(sb, DELALLOC);
3759
3760         /*
3761          * set default s_li_wait_mult for lazyinit, for the case there is
3762          * no mount option specified.
3763          */
3764         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3765
3766         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3767         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3768             blocksize > EXT4_MAX_BLOCK_SIZE) {
3769                 ext4_msg(sb, KERN_ERR,
3770                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3771                          blocksize, le32_to_cpu(es->s_log_block_size));
3772                 goto failed_mount;
3773         }
3774
3775         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3776                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3777                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3778         } else {
3779                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3780                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3781                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
3782                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
3783                                  sbi->s_first_ino);
3784                         goto failed_mount;
3785                 }
3786                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3787                     (!is_power_of_2(sbi->s_inode_size)) ||
3788                     (sbi->s_inode_size > blocksize)) {
3789                         ext4_msg(sb, KERN_ERR,
3790                                "unsupported inode size: %d",
3791                                sbi->s_inode_size);
3792                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
3793                         goto failed_mount;
3794                 }
3795                 /*
3796                  * i_atime_extra is the last extra field available for
3797                  * [acm]times in struct ext4_inode. Checking for that
3798                  * field should suffice to ensure we have extra space
3799                  * for all three.
3800                  */
3801                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
3802                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
3803                         sb->s_time_gran = 1;
3804                 } else {
3805                         sb->s_time_gran = NSEC_PER_SEC;
3806                 }
3807         }
3808         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3809                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3810                         EXT4_GOOD_OLD_INODE_SIZE;
3811                 if (ext4_has_feature_extra_isize(sb)) {
3812                         unsigned v, max = (sbi->s_inode_size -
3813                                            EXT4_GOOD_OLD_INODE_SIZE);
3814
3815                         v = le16_to_cpu(es->s_want_extra_isize);
3816                         if (v > max) {
3817                                 ext4_msg(sb, KERN_ERR,
3818                                          "bad s_want_extra_isize: %d", v);
3819                                 goto failed_mount;
3820                         }
3821                         if (sbi->s_want_extra_isize < v)
3822                                 sbi->s_want_extra_isize = v;
3823
3824                         v = le16_to_cpu(es->s_min_extra_isize);
3825                         if (v > max) {
3826                                 ext4_msg(sb, KERN_ERR,
3827                                          "bad s_min_extra_isize: %d", v);
3828                                 goto failed_mount;
3829                         }
3830                         if (sbi->s_want_extra_isize < v)
3831                                 sbi->s_want_extra_isize = v;
3832                 }
3833         }
3834
3835         if (sbi->s_es->s_mount_opts[0]) {
3836                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3837                                               sizeof(sbi->s_es->s_mount_opts),
3838                                               GFP_KERNEL);
3839                 if (!s_mount_opts)
3840                         goto failed_mount;
3841                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
3842                                    &journal_ioprio, 0)) {
3843                         ext4_msg(sb, KERN_WARNING,
3844                                  "failed to parse options in superblock: %s",
3845                                  s_mount_opts);
3846                 }
3847                 kfree(s_mount_opts);
3848         }
3849         sbi->s_def_mount_opt = sbi->s_mount_opt;
3850         if (!parse_options((char *) data, sb, &journal_devnum,
3851                            &journal_ioprio, 0))
3852                 goto failed_mount;
3853
3854         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3855                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3856                             "with data=journal disables delayed "
3857                             "allocation and O_DIRECT support!\n");
3858                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3859                         ext4_msg(sb, KERN_ERR, "can't mount with "
3860                                  "both data=journal and delalloc");
3861                         goto failed_mount;
3862                 }
3863                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3864                         ext4_msg(sb, KERN_ERR, "can't mount with "
3865                                  "both data=journal and dioread_nolock");
3866                         goto failed_mount;
3867                 }
3868                 if (test_opt(sb, DAX)) {
3869                         ext4_msg(sb, KERN_ERR, "can't mount with "
3870                                  "both data=journal and dax");
3871                         goto failed_mount;
3872                 }
3873                 if (ext4_has_feature_encrypt(sb)) {
3874                         ext4_msg(sb, KERN_WARNING,
3875                                  "encrypted files will use data=ordered "
3876                                  "instead of data journaling mode");
3877                 }
3878                 if (test_opt(sb, DELALLOC))
3879                         clear_opt(sb, DELALLOC);
3880         } else {
3881                 sb->s_iflags |= SB_I_CGROUPWB;
3882         }
3883
3884         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
3885                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
3886
3887         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3888             (ext4_has_compat_features(sb) ||
3889              ext4_has_ro_compat_features(sb) ||
3890              ext4_has_incompat_features(sb)))
3891                 ext4_msg(sb, KERN_WARNING,
3892                        "feature flags set on rev 0 fs, "
3893                        "running e2fsck is recommended");
3894
3895         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3896                 set_opt2(sb, HURD_COMPAT);
3897                 if (ext4_has_feature_64bit(sb)) {
3898                         ext4_msg(sb, KERN_ERR,
3899                                  "The Hurd can't support 64-bit file systems");
3900                         goto failed_mount;
3901                 }
3902
3903                 /*
3904                  * ea_inode feature uses l_i_version field which is not
3905                  * available in HURD_COMPAT mode.
3906                  */
3907                 if (ext4_has_feature_ea_inode(sb)) {
3908                         ext4_msg(sb, KERN_ERR,
3909                                  "ea_inode feature is not supported for Hurd");
3910                         goto failed_mount;
3911                 }
3912         }
3913
3914         if (IS_EXT2_SB(sb)) {
3915                 if (ext2_feature_set_ok(sb))
3916                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3917                                  "using the ext4 subsystem");
3918                 else {
3919                         /*
3920                          * If we're probing be silent, if this looks like
3921                          * it's actually an ext[34] filesystem.
3922                          */
3923                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3924                                 goto failed_mount;
3925                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3926                                  "to feature incompatibilities");
3927                         goto failed_mount;
3928                 }
3929         }
3930
3931         if (IS_EXT3_SB(sb)) {
3932                 if (ext3_feature_set_ok(sb))
3933                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3934                                  "using the ext4 subsystem");
3935                 else {
3936                         /*
3937                          * If we're probing be silent, if this looks like
3938                          * it's actually an ext4 filesystem.
3939                          */
3940                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3941                                 goto failed_mount;
3942                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3943                                  "to feature incompatibilities");
3944                         goto failed_mount;
3945                 }
3946         }
3947
3948         /*
3949          * Check feature flags regardless of the revision level, since we
3950          * previously didn't change the revision level when setting the flags,
3951          * so there is a chance incompat flags are set on a rev 0 filesystem.
3952          */
3953         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
3954                 goto failed_mount;
3955
3956         if (le32_to_cpu(es->s_log_block_size) >
3957             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3958                 ext4_msg(sb, KERN_ERR,
3959                          "Invalid log block size: %u",
3960                          le32_to_cpu(es->s_log_block_size));
3961                 goto failed_mount;
3962         }
3963         if (le32_to_cpu(es->s_log_cluster_size) >
3964             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3965                 ext4_msg(sb, KERN_ERR,
3966                          "Invalid log cluster size: %u",
3967                          le32_to_cpu(es->s_log_cluster_size));
3968                 goto failed_mount;
3969         }
3970
3971         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
3972                 ext4_msg(sb, KERN_ERR,
3973                          "Number of reserved GDT blocks insanely large: %d",
3974                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
3975                 goto failed_mount;
3976         }
3977
3978         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3979                 if (ext4_has_feature_inline_data(sb)) {
3980                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
3981                                         " that may contain inline data");
3982                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX;
3983                 }
3984                 if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
3985                         ext4_msg(sb, KERN_ERR,
3986                                 "DAX unsupported by block device. Turning off DAX.");
3987                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX;
3988                 }
3989         }
3990
3991         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
3992                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
3993                          es->s_encryption_level);
3994                 goto failed_mount;
3995         }
3996
3997         if (sb->s_blocksize != blocksize) {
3998                 /* Validate the filesystem blocksize */
3999                 if (!sb_set_blocksize(sb, blocksize)) {
4000                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4001                                         blocksize);
4002                         goto failed_mount;
4003                 }
4004
4005                 brelse(bh);
4006                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4007                 offset = do_div(logical_sb_block, blocksize);
4008                 bh = sb_bread_unmovable(sb, logical_sb_block);
4009                 if (!bh) {
4010                         ext4_msg(sb, KERN_ERR,
4011                                "Can't read superblock on 2nd try");
4012                         goto failed_mount;
4013                 }
4014                 es = (struct ext4_super_block *)(bh->b_data + offset);
4015                 sbi->s_es = es;
4016                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4017                         ext4_msg(sb, KERN_ERR,
4018                                "Magic mismatch, very weird!");
4019                         goto failed_mount;
4020                 }
4021         }
4022
4023         has_huge_files = ext4_has_feature_huge_file(sb);
4024         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4025                                                       has_huge_files);
4026         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4027
4028         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4029         if (ext4_has_feature_64bit(sb)) {
4030                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4031                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4032                     !is_power_of_2(sbi->s_desc_size)) {
4033                         ext4_msg(sb, KERN_ERR,
4034                                "unsupported descriptor size %lu",
4035                                sbi->s_desc_size);
4036                         goto failed_mount;
4037                 }
4038         } else
4039                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4040
4041         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4042         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4043
4044         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4045         if (sbi->s_inodes_per_block == 0)
4046                 goto cantfind_ext4;
4047         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4048             sbi->s_inodes_per_group > blocksize * 8) {
4049                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4050                          sbi->s_inodes_per_group);
4051                 goto failed_mount;
4052         }
4053         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4054                                         sbi->s_inodes_per_block;
4055         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4056         sbi->s_sbh = bh;
4057         sbi->s_mount_state = le16_to_cpu(es->s_state);
4058         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4059         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4060
4061         for (i = 0; i < 4; i++)
4062                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4063         sbi->s_def_hash_version = es->s_def_hash_version;
4064         if (ext4_has_feature_dir_index(sb)) {
4065                 i = le32_to_cpu(es->s_flags);
4066                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4067                         sbi->s_hash_unsigned = 3;
4068                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4069 #ifdef __CHAR_UNSIGNED__
4070                         if (!sb_rdonly(sb))
4071                                 es->s_flags |=
4072                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4073                         sbi->s_hash_unsigned = 3;
4074 #else
4075                         if (!sb_rdonly(sb))
4076                                 es->s_flags |=
4077                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4078 #endif
4079                 }
4080         }
4081
4082         /* Handle clustersize */
4083         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4084         has_bigalloc = ext4_has_feature_bigalloc(sb);
4085         if (has_bigalloc) {
4086                 if (clustersize < blocksize) {
4087                         ext4_msg(sb, KERN_ERR,
4088                                  "cluster size (%d) smaller than "
4089                                  "block size (%d)", clustersize, blocksize);
4090                         goto failed_mount;
4091                 }
4092                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4093                         le32_to_cpu(es->s_log_block_size);
4094                 sbi->s_clusters_per_group =
4095                         le32_to_cpu(es->s_clusters_per_group);
4096                 if (sbi->s_clusters_per_group > blocksize * 8) {
4097                         ext4_msg(sb, KERN_ERR,
4098                                  "#clusters per group too big: %lu",
4099                                  sbi->s_clusters_per_group);
4100                         goto failed_mount;
4101                 }
4102                 if (sbi->s_blocks_per_group !=
4103                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4104                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4105                                  "clusters per group (%lu) inconsistent",
4106                                  sbi->s_blocks_per_group,
4107                                  sbi->s_clusters_per_group);
4108                         goto failed_mount;
4109                 }
4110         } else {
4111                 if (clustersize != blocksize) {
4112                         ext4_msg(sb, KERN_ERR,
4113                                  "fragment/cluster size (%d) != "
4114                                  "block size (%d)", clustersize, blocksize);
4115                         goto failed_mount;
4116                 }
4117                 if (sbi->s_blocks_per_group > blocksize * 8) {
4118                         ext4_msg(sb, KERN_ERR,
4119                                  "#blocks per group too big: %lu",
4120                                  sbi->s_blocks_per_group);
4121                         goto failed_mount;
4122                 }
4123                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4124                 sbi->s_cluster_bits = 0;
4125         }
4126         sbi->s_cluster_ratio = clustersize / blocksize;
4127
4128         /* Do we have standard group size of clustersize * 8 blocks ? */
4129         if (sbi->s_blocks_per_group == clustersize << 3)
4130                 set_opt2(sb, STD_GROUP_SIZE);
4131
4132         /*
4133          * Test whether we have more sectors than will fit in sector_t,
4134          * and whether the max offset is addressable by the page cache.
4135          */
4136         err = generic_check_addressable(sb->s_blocksize_bits,
4137                                         ext4_blocks_count(es));
4138         if (err) {
4139                 ext4_msg(sb, KERN_ERR, "filesystem"
4140                          " too large to mount safely on this system");
4141                 if (sizeof(sector_t) < 8)
4142                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
4143                 goto failed_mount;
4144         }
4145
4146         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4147                 goto cantfind_ext4;
4148
4149         /* check blocks count against device size */
4150         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4151         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4152                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4153                        "exceeds size of device (%llu blocks)",
4154                        ext4_blocks_count(es), blocks_count);
4155                 goto failed_mount;
4156         }
4157
4158         /*
4159          * It makes no sense for the first data block to be beyond the end
4160          * of the filesystem.
4161          */
4162         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4163                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4164                          "block %u is beyond end of filesystem (%llu)",
4165                          le32_to_cpu(es->s_first_data_block),
4166                          ext4_blocks_count(es));
4167                 goto failed_mount;
4168         }
4169         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4170             (sbi->s_cluster_ratio == 1)) {
4171                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4172                          "block is 0 with a 1k block and cluster size");
4173                 goto failed_mount;
4174         }
4175
4176         blocks_count = (ext4_blocks_count(es) -
4177                         le32_to_cpu(es->s_first_data_block) +
4178                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4179         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4180         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4181                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4182                        "(block count %llu, first data block %u, "
4183                        "blocks per group %lu)", blocks_count,
4184                        ext4_blocks_count(es),
4185                        le32_to_cpu(es->s_first_data_block),
4186                        EXT4_BLOCKS_PER_GROUP(sb));
4187                 goto failed_mount;
4188         }
4189         sbi->s_groups_count = blocks_count;
4190         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4191                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4192         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4193             le32_to_cpu(es->s_inodes_count)) {
4194                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4195                          le32_to_cpu(es->s_inodes_count),
4196                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4197                 ret = -EINVAL;
4198                 goto failed_mount;
4199         }
4200         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4201                    EXT4_DESC_PER_BLOCK(sb);
4202         if (ext4_has_feature_meta_bg(sb)) {
4203                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4204                         ext4_msg(sb, KERN_WARNING,
4205                                  "first meta block group too large: %u "
4206                                  "(group descriptor block count %u)",
4207                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4208                         goto failed_mount;
4209                 }
4210         }
4211         rcu_assign_pointer(sbi->s_group_desc,
4212                            kvmalloc_array(db_count,
4213                                           sizeof(struct buffer_head *),
4214                                           GFP_KERNEL));
4215         if (sbi->s_group_desc == NULL) {
4216                 ext4_msg(sb, KERN_ERR, "not enough memory");
4217                 ret = -ENOMEM;
4218                 goto failed_mount;
4219         }
4220
4221         bgl_lock_init(sbi->s_blockgroup_lock);
4222
4223         /* Pre-read the descriptors into the buffer cache */
4224         for (i = 0; i < db_count; i++) {
4225                 block = descriptor_loc(sb, logical_sb_block, i);
4226                 sb_breadahead_unmovable(sb, block);
4227         }
4228
4229         for (i = 0; i < db_count; i++) {
4230                 struct buffer_head *bh;
4231
4232                 block = descriptor_loc(sb, logical_sb_block, i);
4233                 bh = sb_bread_unmovable(sb, block);
4234                 if (!bh) {
4235                         ext4_msg(sb, KERN_ERR,
4236                                "can't read group descriptor %d", i);
4237                         db_count = i;
4238                         goto failed_mount2;
4239                 }
4240                 rcu_read_lock();
4241                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4242                 rcu_read_unlock();
4243         }
4244         sbi->s_gdb_count = db_count;
4245         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4246                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4247                 ret = -EFSCORRUPTED;
4248                 goto failed_mount2;
4249         }
4250
4251         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4252
4253         /* Register extent status tree shrinker */
4254         if (ext4_es_register_shrinker(sbi))
4255                 goto failed_mount3;
4256
4257         sbi->s_stripe = ext4_get_stripe_size(sbi);
4258         sbi->s_extent_max_zeroout_kb = 32;
4259
4260         /*
4261          * set up enough so that it can read an inode
4262          */
4263         sb->s_op = &ext4_sops;
4264         sb->s_export_op = &ext4_export_ops;
4265         sb->s_xattr = ext4_xattr_handlers;
4266 #ifdef CONFIG_EXT4_FS_ENCRYPTION
4267         sb->s_cop = &ext4_cryptops;
4268 #endif
4269 #ifdef CONFIG_QUOTA
4270         sb->dq_op = &ext4_quota_operations;
4271         if (ext4_has_feature_quota(sb))
4272                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4273         else
4274                 sb->s_qcop = &ext4_qctl_operations;
4275         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4276 #endif
4277         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4278
4279         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4280         mutex_init(&sbi->s_orphan_lock);
4281
4282         sb->s_root = NULL;
4283
4284         needs_recovery = (es->s_last_orphan != 0 ||
4285                           ext4_has_feature_journal_needs_recovery(sb));
4286
4287         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4288                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4289                         goto failed_mount3a;
4290
4291         /*
4292          * The first inode we look at is the journal inode.  Don't try
4293          * root first: it may be modified in the journal!
4294          */
4295         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4296                 err = ext4_load_journal(sb, es, journal_devnum);
4297                 if (err)
4298                         goto failed_mount3a;
4299         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4300                    ext4_has_feature_journal_needs_recovery(sb)) {
4301                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4302                        "suppressed and not mounted read-only");
4303                 goto failed_mount_wq;
4304         } else {
4305                 /* Nojournal mode, all journal mount options are illegal */
4306                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4307                         ext4_msg(sb, KERN_ERR, "can't mount with "
4308                                  "journal_checksum, fs mounted w/o journal");
4309                         goto failed_mount_wq;
4310                 }
4311                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4312                         ext4_msg(sb, KERN_ERR, "can't mount with "
4313                                  "journal_async_commit, fs mounted w/o journal");
4314                         goto failed_mount_wq;
4315                 }
4316                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4317                         ext4_msg(sb, KERN_ERR, "can't mount with "
4318                                  "commit=%lu, fs mounted w/o journal",
4319                                  sbi->s_commit_interval / HZ);
4320                         goto failed_mount_wq;
4321                 }
4322                 if (EXT4_MOUNT_DATA_FLAGS &
4323                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4324                         ext4_msg(sb, KERN_ERR, "can't mount with "
4325                                  "data=, fs mounted w/o journal");
4326                         goto failed_mount_wq;
4327                 }
4328                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4329                 clear_opt(sb, JOURNAL_CHECKSUM);
4330                 clear_opt(sb, DATA_FLAGS);
4331                 sbi->s_journal = NULL;
4332                 needs_recovery = 0;
4333                 goto no_journal;
4334         }
4335
4336         if (ext4_has_feature_64bit(sb) &&
4337             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4338                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4339                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4340                 goto failed_mount_wq;
4341         }
4342
4343         if (!set_journal_csum_feature_set(sb)) {
4344                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4345                          "feature set");
4346                 goto failed_mount_wq;
4347         }
4348
4349         /* We have now updated the journal if required, so we can
4350          * validate the data journaling mode. */
4351         switch (test_opt(sb, DATA_FLAGS)) {
4352         case 0:
4353                 /* No mode set, assume a default based on the journal
4354                  * capabilities: ORDERED_DATA if the journal can
4355                  * cope, else JOURNAL_DATA
4356                  */
4357                 if (jbd2_journal_check_available_features
4358                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4359                         set_opt(sb, ORDERED_DATA);
4360                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4361                 } else {
4362                         set_opt(sb, JOURNAL_DATA);
4363                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4364                 }
4365                 break;
4366
4367         case EXT4_MOUNT_ORDERED_DATA:
4368         case EXT4_MOUNT_WRITEBACK_DATA:
4369                 if (!jbd2_journal_check_available_features
4370                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4371                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4372                                "requested data journaling mode");
4373                         goto failed_mount_wq;
4374                 }
4375         default:
4376                 break;
4377         }
4378
4379         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4380             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4381                 ext4_msg(sb, KERN_ERR, "can't mount with "
4382                         "journal_async_commit in data=ordered mode");
4383                 goto failed_mount_wq;
4384         }
4385
4386         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4387
4388         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4389
4390 no_journal:
4391         if (!test_opt(sb, NO_MBCACHE)) {
4392                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4393                 if (!sbi->s_ea_block_cache) {
4394                         ext4_msg(sb, KERN_ERR,
4395                                  "Failed to create ea_block_cache");
4396                         goto failed_mount_wq;
4397                 }
4398
4399                 if (ext4_has_feature_ea_inode(sb)) {
4400                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4401                         if (!sbi->s_ea_inode_cache) {
4402                                 ext4_msg(sb, KERN_ERR,
4403                                          "Failed to create ea_inode_cache");
4404                                 goto failed_mount_wq;
4405                         }
4406                 }
4407         }
4408
4409         if ((DUMMY_ENCRYPTION_ENABLED(sbi) || ext4_has_feature_encrypt(sb)) &&
4410             (blocksize != PAGE_SIZE)) {
4411                 ext4_msg(sb, KERN_ERR,
4412                          "Unsupported blocksize for fs encryption");
4413                 goto failed_mount_wq;
4414         }
4415
4416         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4417             !ext4_has_feature_encrypt(sb)) {
4418                 ext4_set_feature_encrypt(sb);
4419                 ext4_commit_super(sb, 1);
4420         }
4421
4422         /*
4423          * Get the # of file system overhead blocks from the
4424          * superblock if present.
4425          */
4426         sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4427         /* ignore the precalculated value if it is ridiculous */
4428         if (sbi->s_overhead > ext4_blocks_count(es))
4429                 sbi->s_overhead = 0;
4430         /*
4431          * If the bigalloc feature is not enabled recalculating the
4432          * overhead doesn't take long, so we might as well just redo
4433          * it to make sure we are using the correct value.
4434          */
4435         if (!ext4_has_feature_bigalloc(sb))
4436                 sbi->s_overhead = 0;
4437         if (sbi->s_overhead == 0) {
4438                 err = ext4_calculate_overhead(sb);
4439                 if (err)
4440                         goto failed_mount_wq;
4441         }
4442
4443         /*
4444          * The maximum number of concurrent works can be high and
4445          * concurrency isn't really necessary.  Limit it to 1.
4446          */
4447         EXT4_SB(sb)->rsv_conversion_wq =
4448                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4449         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4450                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4451                 ret = -ENOMEM;
4452                 goto failed_mount4;
4453         }
4454
4455         /*
4456          * The jbd2_journal_load will have done any necessary log recovery,
4457          * so we can safely mount the rest of the filesystem now.
4458          */
4459
4460         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4461         if (IS_ERR(root)) {
4462                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4463                 ret = PTR_ERR(root);
4464                 root = NULL;
4465                 goto failed_mount4;
4466         }
4467         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4468                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4469                 iput(root);
4470                 goto failed_mount4;
4471         }
4472         sb->s_root = d_make_root(root);
4473         if (!sb->s_root) {
4474                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4475                 ret = -ENOMEM;
4476                 goto failed_mount4;
4477         }
4478
4479         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4480         if (ret == -EROFS) {
4481                 sb->s_flags |= SB_RDONLY;
4482                 ret = 0;
4483         } else if (ret)
4484                 goto failed_mount4a;
4485
4486         ext4_set_resv_clusters(sb);
4487
4488         if (test_opt(sb, BLOCK_VALIDITY)) {
4489                 err = ext4_setup_system_zone(sb);
4490                 if (err) {
4491                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
4492                                  "zone (%d)", err);
4493                         goto failed_mount4a;
4494                 }
4495         }
4496
4497         ext4_ext_init(sb);
4498         err = ext4_mb_init(sb);
4499         if (err) {
4500                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4501                          err);
4502                 goto failed_mount5;
4503         }
4504
4505         block = ext4_count_free_clusters(sb);
4506         ext4_free_blocks_count_set(sbi->s_es,
4507                                    EXT4_C2B(sbi, block));
4508         ext4_superblock_csum_set(sb);
4509         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4510                                   GFP_KERNEL);
4511         if (!err) {
4512                 unsigned long freei = ext4_count_free_inodes(sb);
4513                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4514                 ext4_superblock_csum_set(sb);
4515                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4516                                           GFP_KERNEL);
4517         }
4518         if (!err)
4519                 err = percpu_counter_init(&sbi->s_dirs_counter,
4520                                           ext4_count_dirs(sb), GFP_KERNEL);
4521         if (!err)
4522                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4523                                           GFP_KERNEL);
4524         if (!err)
4525                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
4526
4527         if (err) {
4528                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4529                 goto failed_mount6;
4530         }
4531
4532         if (ext4_has_feature_flex_bg(sb))
4533                 if (!ext4_fill_flex_info(sb)) {
4534                         ext4_msg(sb, KERN_ERR,
4535                                "unable to initialize "
4536                                "flex_bg meta info!");
4537                         ret = -ENOMEM;
4538                         goto failed_mount6;
4539                 }
4540
4541         err = ext4_register_li_request(sb, first_not_zeroed);
4542         if (err)
4543                 goto failed_mount6;
4544
4545         err = ext4_register_sysfs(sb);
4546         if (err)
4547                 goto failed_mount7;
4548
4549 #ifdef CONFIG_QUOTA
4550         /* Enable quota usage during mount. */
4551         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4552                 err = ext4_enable_quotas(sb);
4553                 if (err)
4554                         goto failed_mount8;
4555         }
4556 #endif  /* CONFIG_QUOTA */
4557
4558         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4559         ext4_orphan_cleanup(sb, es);
4560         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4561         if (needs_recovery) {
4562                 ext4_msg(sb, KERN_INFO, "recovery complete");
4563                 err = ext4_mark_recovery_complete(sb, es);
4564                 if (err)
4565                         goto failed_mount8;
4566         }
4567         if (EXT4_SB(sb)->s_journal) {
4568                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4569                         descr = " journalled data mode";
4570                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4571                         descr = " ordered data mode";
4572                 else
4573                         descr = " writeback data mode";
4574         } else
4575                 descr = "out journal";
4576
4577         if (test_opt(sb, DISCARD)) {
4578                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4579                 if (!blk_queue_discard(q))
4580                         ext4_msg(sb, KERN_WARNING,
4581                                  "mounting with \"discard\" option, but "
4582                                  "the device does not support discard");
4583         }
4584
4585         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4586                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4587                          "Opts: %.*s%s%s", descr,
4588                          (int) sizeof(sbi->s_es->s_mount_opts),
4589                          sbi->s_es->s_mount_opts,
4590                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4591
4592         if (es->s_error_count)
4593                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4594
4595         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4596         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4597         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4598         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4599
4600         kfree(orig_data);
4601         return 0;
4602
4603 cantfind_ext4:
4604         if (!silent)
4605                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4606         goto failed_mount;
4607
4608 failed_mount8:
4609         ext4_unregister_sysfs(sb);
4610         kobject_put(&sbi->s_kobj);
4611 failed_mount7:
4612         ext4_unregister_li_request(sb);
4613 failed_mount6:
4614         ext4_mb_release(sb);
4615         rcu_read_lock();
4616         flex_groups = rcu_dereference(sbi->s_flex_groups);
4617         if (flex_groups) {
4618                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
4619                         kvfree(flex_groups[i]);
4620                 kvfree(flex_groups);
4621         }
4622         rcu_read_unlock();
4623         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4624         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4625         percpu_counter_destroy(&sbi->s_dirs_counter);
4626         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4627         percpu_free_rwsem(&sbi->s_writepages_rwsem);
4628 failed_mount5:
4629         ext4_ext_release(sb);
4630         ext4_release_system_zone(sb);
4631 failed_mount4a:
4632         dput(sb->s_root);
4633         sb->s_root = NULL;
4634 failed_mount4:
4635         ext4_msg(sb, KERN_ERR, "mount failed");
4636         if (EXT4_SB(sb)->rsv_conversion_wq)
4637                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4638 failed_mount_wq:
4639         if (sbi->s_ea_inode_cache) {
4640                 ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4641                 sbi->s_ea_inode_cache = NULL;
4642         }
4643         if (sbi->s_ea_block_cache) {
4644                 ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4645                 sbi->s_ea_block_cache = NULL;
4646         }
4647         if (sbi->s_journal) {
4648                 jbd2_journal_destroy(sbi->s_journal);
4649                 sbi->s_journal = NULL;
4650         }
4651 failed_mount3a:
4652         ext4_es_unregister_shrinker(sbi);
4653 failed_mount3:
4654         del_timer_sync(&sbi->s_err_report);
4655         if (sbi->s_mmp_tsk)
4656                 kthread_stop(sbi->s_mmp_tsk);
4657 failed_mount2:
4658         rcu_read_lock();
4659         group_desc = rcu_dereference(sbi->s_group_desc);
4660         for (i = 0; i < db_count; i++)
4661                 brelse(group_desc[i]);
4662         kvfree(group_desc);
4663         rcu_read_unlock();
4664 failed_mount:
4665         if (sbi->s_chksum_driver)
4666                 crypto_free_shash(sbi->s_chksum_driver);
4667 #ifdef CONFIG_QUOTA
4668         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4669                 kfree(sbi->s_qf_names[i]);
4670 #endif
4671         ext4_blkdev_remove(sbi);
4672         brelse(bh);
4673 out_fail:
4674         sb->s_fs_info = NULL;
4675         kfree(sbi->s_blockgroup_lock);
4676 out_free_base:
4677         kfree(sbi);
4678         kfree(orig_data);
4679         fs_put_dax(dax_dev);
4680         return err ? err : ret;
4681 }
4682
4683 /*
4684  * Setup any per-fs journal parameters now.  We'll do this both on
4685  * initial mount, once the journal has been initialised but before we've
4686  * done any recovery; and again on any subsequent remount.
4687  */
4688 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4689 {
4690         struct ext4_sb_info *sbi = EXT4_SB(sb);
4691
4692         journal->j_commit_interval = sbi->s_commit_interval;
4693         journal->j_min_batch_time = sbi->s_min_batch_time;
4694         journal->j_max_batch_time = sbi->s_max_batch_time;
4695
4696         write_lock(&journal->j_state_lock);
4697         if (test_opt(sb, BARRIER))
4698                 journal->j_flags |= JBD2_BARRIER;
4699         else
4700                 journal->j_flags &= ~JBD2_BARRIER;
4701         if (test_opt(sb, DATA_ERR_ABORT))
4702                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4703         else
4704                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4705         write_unlock(&journal->j_state_lock);
4706 }
4707
4708 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4709                                              unsigned int journal_inum)
4710 {
4711         struct inode *journal_inode;
4712
4713         /*
4714          * Test for the existence of a valid inode on disk.  Bad things
4715          * happen if we iget() an unused inode, as the subsequent iput()
4716          * will try to delete it.
4717          */
4718         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
4719         if (IS_ERR(journal_inode)) {
4720                 ext4_msg(sb, KERN_ERR, "no journal found");
4721                 return NULL;
4722         }
4723         if (!journal_inode->i_nlink) {
4724                 make_bad_inode(journal_inode);
4725                 iput(journal_inode);
4726                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4727                 return NULL;
4728         }
4729
4730         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4731                   journal_inode, journal_inode->i_size);
4732         if (!S_ISREG(journal_inode->i_mode)) {
4733                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4734                 iput(journal_inode);
4735                 return NULL;
4736         }
4737         return journal_inode;
4738 }
4739
4740 static journal_t *ext4_get_journal(struct super_block *sb,
4741                                    unsigned int journal_inum)
4742 {
4743         struct inode *journal_inode;
4744         journal_t *journal;
4745
4746         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
4747                 return NULL;
4748
4749         journal_inode = ext4_get_journal_inode(sb, journal_inum);
4750         if (!journal_inode)
4751                 return NULL;
4752
4753         journal = jbd2_journal_init_inode(journal_inode);
4754         if (!journal) {
4755                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4756                 iput(journal_inode);
4757                 return NULL;
4758         }
4759         journal->j_private = sb;
4760         ext4_init_journal_params(sb, journal);
4761         return journal;
4762 }
4763
4764 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4765                                        dev_t j_dev)
4766 {
4767         struct buffer_head *bh;
4768         journal_t *journal;
4769         ext4_fsblk_t start;
4770         ext4_fsblk_t len;
4771         int hblock, blocksize;
4772         ext4_fsblk_t sb_block;
4773         unsigned long offset;
4774         struct ext4_super_block *es;
4775         struct block_device *bdev;
4776
4777         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
4778                 return NULL;
4779
4780         bdev = ext4_blkdev_get(j_dev, sb);
4781         if (bdev == NULL)
4782                 return NULL;
4783
4784         blocksize = sb->s_blocksize;
4785         hblock = bdev_logical_block_size(bdev);
4786         if (blocksize < hblock) {
4787                 ext4_msg(sb, KERN_ERR,
4788                         "blocksize too small for journal device");
4789                 goto out_bdev;
4790         }
4791
4792         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4793         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4794         set_blocksize(bdev, blocksize);
4795         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4796                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4797                        "external journal");
4798                 goto out_bdev;
4799         }
4800
4801         es = (struct ext4_super_block *) (bh->b_data + offset);
4802         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4803             !(le32_to_cpu(es->s_feature_incompat) &
4804               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4805                 ext4_msg(sb, KERN_ERR, "external journal has "
4806                                         "bad superblock");
4807                 brelse(bh);
4808                 goto out_bdev;
4809         }
4810
4811         if ((le32_to_cpu(es->s_feature_ro_compat) &
4812              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4813             es->s_checksum != ext4_superblock_csum(sb, es)) {
4814                 ext4_msg(sb, KERN_ERR, "external journal has "
4815                                        "corrupt superblock");
4816                 brelse(bh);
4817                 goto out_bdev;
4818         }
4819
4820         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4821                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4822                 brelse(bh);
4823                 goto out_bdev;
4824         }
4825
4826         len = ext4_blocks_count(es);
4827         start = sb_block + 1;
4828         brelse(bh);     /* we're done with the superblock */
4829
4830         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4831                                         start, len, blocksize);
4832         if (!journal) {
4833                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4834                 goto out_bdev;
4835         }
4836         journal->j_private = sb;
4837         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4838         wait_on_buffer(journal->j_sb_buffer);
4839         if (!buffer_uptodate(journal->j_sb_buffer)) {
4840                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4841                 goto out_journal;
4842         }
4843         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4844                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4845                                         "user (unsupported) - %d",
4846                         be32_to_cpu(journal->j_superblock->s_nr_users));
4847                 goto out_journal;
4848         }
4849         EXT4_SB(sb)->journal_bdev = bdev;
4850         ext4_init_journal_params(sb, journal);
4851         return journal;
4852
4853 out_journal:
4854         jbd2_journal_destroy(journal);
4855 out_bdev:
4856         ext4_blkdev_put(bdev);
4857         return NULL;
4858 }
4859
4860 static int ext4_load_journal(struct super_block *sb,
4861                              struct ext4_super_block *es,
4862                              unsigned long journal_devnum)
4863 {
4864         journal_t *journal;
4865         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4866         dev_t journal_dev;
4867         int err = 0;
4868         int really_read_only;
4869         int journal_dev_ro;
4870
4871         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
4872                 return -EFSCORRUPTED;
4873
4874         if (journal_devnum &&
4875             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4876                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4877                         "numbers have changed");
4878                 journal_dev = new_decode_dev(journal_devnum);
4879         } else
4880                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4881
4882         if (journal_inum && journal_dev) {
4883                 ext4_msg(sb, KERN_ERR,
4884                          "filesystem has both journal inode and journal device!");
4885                 return -EINVAL;
4886         }
4887
4888         if (journal_inum) {
4889                 journal = ext4_get_journal(sb, journal_inum);
4890                 if (!journal)
4891                         return -EINVAL;
4892         } else {
4893                 journal = ext4_get_dev_journal(sb, journal_dev);
4894                 if (!journal)
4895                         return -EINVAL;
4896         }
4897
4898         journal_dev_ro = bdev_read_only(journal->j_dev);
4899         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
4900
4901         if (journal_dev_ro && !sb_rdonly(sb)) {
4902                 ext4_msg(sb, KERN_ERR,
4903                          "journal device read-only, try mounting with '-o ro'");
4904                 err = -EROFS;
4905                 goto err_out;
4906         }
4907
4908         /*
4909          * Are we loading a blank journal or performing recovery after a
4910          * crash?  For recovery, we need to check in advance whether we
4911          * can get read-write access to the device.
4912          */
4913         if (ext4_has_feature_journal_needs_recovery(sb)) {
4914                 if (sb_rdonly(sb)) {
4915                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4916                                         "required on readonly filesystem");
4917                         if (really_read_only) {
4918                                 ext4_msg(sb, KERN_ERR, "write access "
4919                                         "unavailable, cannot proceed "
4920                                         "(try mounting with noload)");
4921                                 err = -EROFS;
4922                                 goto err_out;
4923                         }
4924                         ext4_msg(sb, KERN_INFO, "write access will "
4925                                "be enabled during recovery");
4926                 }
4927         }
4928
4929         if (!(journal->j_flags & JBD2_BARRIER))
4930                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4931
4932         if (!ext4_has_feature_journal_needs_recovery(sb))
4933                 err = jbd2_journal_wipe(journal, !really_read_only);
4934         if (!err) {
4935                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4936                 if (save)
4937                         memcpy(save, ((char *) es) +
4938                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4939                 err = jbd2_journal_load(journal);
4940                 if (save)
4941                         memcpy(((char *) es) + EXT4_S_ERR_START,
4942                                save, EXT4_S_ERR_LEN);
4943                 kfree(save);
4944         }
4945
4946         if (err) {
4947                 ext4_msg(sb, KERN_ERR, "error loading journal");
4948                 goto err_out;
4949         }
4950
4951         EXT4_SB(sb)->s_journal = journal;
4952         err = ext4_clear_journal_err(sb, es);
4953         if (err) {
4954                 EXT4_SB(sb)->s_journal = NULL;
4955                 jbd2_journal_destroy(journal);
4956                 return err;
4957         }
4958
4959         if (!really_read_only && journal_devnum &&
4960             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4961                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4962
4963                 /* Make sure we flush the recovery flag to disk. */
4964                 ext4_commit_super(sb, 1);
4965         }
4966
4967         return 0;
4968
4969 err_out:
4970         jbd2_journal_destroy(journal);
4971         return err;
4972 }
4973
4974 static int ext4_commit_super(struct super_block *sb, int sync)
4975 {
4976         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4977         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4978         int error = 0;
4979
4980         if (!sbh)
4981                 return -EINVAL;
4982         if (block_device_ejected(sb))
4983                 return -ENODEV;
4984
4985         /*
4986          * If the file system is mounted read-only, don't update the
4987          * superblock write time.  This avoids updating the superblock
4988          * write time when we are mounting the root file system
4989          * read/only but we need to replay the journal; at that point,
4990          * for people who are east of GMT and who make their clock
4991          * tick in localtime for Windows bug-for-bug compatibility,
4992          * the clock is set in the future, and this will cause e2fsck
4993          * to complain and force a full file system check.
4994          */
4995         if (!(sb->s_flags & SB_RDONLY))
4996                 ext4_update_tstamp(es, s_wtime);
4997         if (sb->s_bdev->bd_part)
4998                 es->s_kbytes_written =
4999                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5000                             ((part_stat_read(sb->s_bdev->bd_part,
5001                                              sectors[STAT_WRITE]) -
5002                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
5003         else
5004                 es->s_kbytes_written =
5005                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5006         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5007                 ext4_free_blocks_count_set(es,
5008                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5009                                 &EXT4_SB(sb)->s_freeclusters_counter)));
5010         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5011                 es->s_free_inodes_count =
5012                         cpu_to_le32(percpu_counter_sum_positive(
5013                                 &EXT4_SB(sb)->s_freeinodes_counter));
5014         BUFFER_TRACE(sbh, "marking dirty");
5015         ext4_superblock_csum_set(sb);
5016         if (sync)
5017                 lock_buffer(sbh);
5018         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5019                 /*
5020                  * Oh, dear.  A previous attempt to write the
5021                  * superblock failed.  This could happen because the
5022                  * USB device was yanked out.  Or it could happen to
5023                  * be a transient write error and maybe the block will
5024                  * be remapped.  Nothing we can do but to retry the
5025                  * write and hope for the best.
5026                  */
5027                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5028                        "superblock detected");
5029                 clear_buffer_write_io_error(sbh);
5030                 set_buffer_uptodate(sbh);
5031         }
5032         mark_buffer_dirty(sbh);
5033         if (sync) {
5034                 unlock_buffer(sbh);
5035                 error = __sync_dirty_buffer(sbh,
5036                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5037                 if (buffer_write_io_error(sbh)) {
5038                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5039                                "superblock");
5040                         clear_buffer_write_io_error(sbh);
5041                         set_buffer_uptodate(sbh);
5042                 }
5043         }
5044         return error;
5045 }
5046
5047 /*
5048  * Have we just finished recovery?  If so, and if we are mounting (or
5049  * remounting) the filesystem readonly, then we will end up with a
5050  * consistent fs on disk.  Record that fact.
5051  */
5052 static int ext4_mark_recovery_complete(struct super_block *sb,
5053                                        struct ext4_super_block *es)
5054 {
5055         int err;
5056         journal_t *journal = EXT4_SB(sb)->s_journal;
5057
5058         if (!ext4_has_feature_journal(sb)) {
5059                 if (journal != NULL) {
5060                         ext4_error(sb, "Journal got removed while the fs was "
5061                                    "mounted!");
5062                         return -EFSCORRUPTED;
5063                 }
5064                 return 0;
5065         }
5066         jbd2_journal_lock_updates(journal);
5067         err = jbd2_journal_flush(journal);
5068         if (err < 0)
5069                 goto out;
5070
5071         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5072                 ext4_clear_feature_journal_needs_recovery(sb);
5073                 ext4_commit_super(sb, 1);
5074         }
5075 out:
5076         jbd2_journal_unlock_updates(journal);
5077         return err;
5078 }
5079
5080 /*
5081  * If we are mounting (or read-write remounting) a filesystem whose journal
5082  * has recorded an error from a previous lifetime, move that error to the
5083  * main filesystem now.
5084  */
5085 static int ext4_clear_journal_err(struct super_block *sb,
5086                                    struct ext4_super_block *es)
5087 {
5088         journal_t *journal;
5089         int j_errno;
5090         const char *errstr;
5091
5092         if (!ext4_has_feature_journal(sb)) {
5093                 ext4_error(sb, "Journal got removed while the fs was mounted!");
5094                 return -EFSCORRUPTED;
5095         }
5096
5097         journal = EXT4_SB(sb)->s_journal;
5098
5099         /*
5100          * Now check for any error status which may have been recorded in the
5101          * journal by a prior ext4_error() or ext4_abort()
5102          */
5103
5104         j_errno = jbd2_journal_errno(journal);
5105         if (j_errno) {
5106                 char nbuf[16];
5107
5108                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5109                 ext4_warning(sb, "Filesystem error recorded "
5110                              "from previous mount: %s", errstr);
5111                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5112
5113                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5114                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5115                 ext4_commit_super(sb, 1);
5116
5117                 jbd2_journal_clear_err(journal);
5118                 jbd2_journal_update_sb_errno(journal);
5119         }
5120         return 0;
5121 }
5122
5123 /*
5124  * Force the running and committing transactions to commit,
5125  * and wait on the commit.
5126  */
5127 int ext4_force_commit(struct super_block *sb)
5128 {
5129         journal_t *journal;
5130
5131         if (sb_rdonly(sb))
5132                 return 0;
5133
5134         journal = EXT4_SB(sb)->s_journal;
5135         return ext4_journal_force_commit(journal);
5136 }
5137
5138 static int ext4_sync_fs(struct super_block *sb, int wait)
5139 {
5140         int ret = 0;
5141         tid_t target;
5142         bool needs_barrier = false;
5143         struct ext4_sb_info *sbi = EXT4_SB(sb);
5144
5145         if (unlikely(ext4_forced_shutdown(sbi)))
5146                 return 0;
5147
5148         trace_ext4_sync_fs(sb, wait);
5149         flush_workqueue(sbi->rsv_conversion_wq);
5150         /*
5151          * Writeback quota in non-journalled quota case - journalled quota has
5152          * no dirty dquots
5153          */
5154         dquot_writeback_dquots(sb, -1);
5155         /*
5156          * Data writeback is possible w/o journal transaction, so barrier must
5157          * being sent at the end of the function. But we can skip it if
5158          * transaction_commit will do it for us.
5159          */
5160         if (sbi->s_journal) {
5161                 target = jbd2_get_latest_transaction(sbi->s_journal);
5162                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5163                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5164                         needs_barrier = true;
5165
5166                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5167                         if (wait)
5168                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5169                                                            target);
5170                 }
5171         } else if (wait && test_opt(sb, BARRIER))
5172                 needs_barrier = true;
5173         if (needs_barrier) {
5174                 int err;
5175                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
5176                 if (!ret)
5177                         ret = err;
5178         }
5179
5180         return ret;
5181 }
5182
5183 /*
5184  * LVM calls this function before a (read-only) snapshot is created.  This
5185  * gives us a chance to flush the journal completely and mark the fs clean.
5186  *
5187  * Note that only this function cannot bring a filesystem to be in a clean
5188  * state independently. It relies on upper layer to stop all data & metadata
5189  * modifications.
5190  */
5191 static int ext4_freeze(struct super_block *sb)
5192 {
5193         int error = 0;
5194         journal_t *journal;
5195
5196         if (sb_rdonly(sb))
5197                 return 0;
5198
5199         journal = EXT4_SB(sb)->s_journal;
5200
5201         if (journal) {
5202                 /* Now we set up the journal barrier. */
5203                 jbd2_journal_lock_updates(journal);
5204
5205                 /*
5206                  * Don't clear the needs_recovery flag if we failed to
5207                  * flush the journal.
5208                  */
5209                 error = jbd2_journal_flush(journal);
5210                 if (error < 0)
5211                         goto out;
5212
5213                 /* Journal blocked and flushed, clear needs_recovery flag. */
5214                 ext4_clear_feature_journal_needs_recovery(sb);
5215         }
5216
5217         error = ext4_commit_super(sb, 1);
5218 out:
5219         if (journal)
5220                 /* we rely on upper layer to stop further updates */
5221                 jbd2_journal_unlock_updates(journal);
5222         return error;
5223 }
5224
5225 /*
5226  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5227  * flag here, even though the filesystem is not technically dirty yet.
5228  */
5229 static int ext4_unfreeze(struct super_block *sb)
5230 {
5231         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5232                 return 0;
5233
5234         if (EXT4_SB(sb)->s_journal) {
5235                 /* Reset the needs_recovery flag before the fs is unlocked. */
5236                 ext4_set_feature_journal_needs_recovery(sb);
5237         }
5238
5239         ext4_commit_super(sb, 1);
5240         return 0;
5241 }
5242
5243 /*
5244  * Structure to save mount options for ext4_remount's benefit
5245  */
5246 struct ext4_mount_options {
5247         unsigned long s_mount_opt;
5248         unsigned long s_mount_opt2;
5249         kuid_t s_resuid;
5250         kgid_t s_resgid;
5251         unsigned long s_commit_interval;
5252         u32 s_min_batch_time, s_max_batch_time;
5253 #ifdef CONFIG_QUOTA
5254         int s_jquota_fmt;
5255         char *s_qf_names[EXT4_MAXQUOTAS];
5256 #endif
5257 };
5258
5259 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5260 {
5261         struct ext4_super_block *es;
5262         struct ext4_sb_info *sbi = EXT4_SB(sb);
5263         unsigned long old_sb_flags, vfs_flags;
5264         struct ext4_mount_options old_opts;
5265         int enable_quota = 0;
5266         ext4_group_t g;
5267         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5268         int err = 0;
5269 #ifdef CONFIG_QUOTA
5270         int i, j;
5271         char *to_free[EXT4_MAXQUOTAS];
5272 #endif
5273         char *orig_data = kstrdup(data, GFP_KERNEL);
5274
5275         if (data && !orig_data)
5276                 return -ENOMEM;
5277
5278         /* Store the original options */
5279         old_sb_flags = sb->s_flags;
5280         old_opts.s_mount_opt = sbi->s_mount_opt;
5281         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5282         old_opts.s_resuid = sbi->s_resuid;
5283         old_opts.s_resgid = sbi->s_resgid;
5284         old_opts.s_commit_interval = sbi->s_commit_interval;
5285         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5286         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5287 #ifdef CONFIG_QUOTA
5288         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5289         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5290                 if (sbi->s_qf_names[i]) {
5291                         char *qf_name = get_qf_name(sb, sbi, i);
5292
5293                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5294                         if (!old_opts.s_qf_names[i]) {
5295                                 for (j = 0; j < i; j++)
5296                                         kfree(old_opts.s_qf_names[j]);
5297                                 kfree(orig_data);
5298                                 return -ENOMEM;
5299                         }
5300                 } else
5301                         old_opts.s_qf_names[i] = NULL;
5302 #endif
5303         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5304                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5305
5306         /*
5307          * Some options can be enabled by ext4 and/or by VFS mount flag
5308          * either way we need to make sure it matches in both *flags and
5309          * s_flags. Copy those selected flags from *flags to s_flags
5310          */
5311         vfs_flags = SB_LAZYTIME | SB_I_VERSION;
5312         sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags);
5313
5314         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5315                 err = -EINVAL;
5316                 goto restore_opts;
5317         }
5318
5319         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5320             test_opt(sb, JOURNAL_CHECKSUM)) {
5321                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5322                          "during remount not supported; ignoring");
5323                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5324         }
5325
5326         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5327                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5328                         ext4_msg(sb, KERN_ERR, "can't mount with "
5329                                  "both data=journal and delalloc");
5330                         err = -EINVAL;
5331                         goto restore_opts;
5332                 }
5333                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5334                         ext4_msg(sb, KERN_ERR, "can't mount with "
5335                                  "both data=journal and dioread_nolock");
5336                         err = -EINVAL;
5337                         goto restore_opts;
5338                 }
5339         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5340                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5341                         ext4_msg(sb, KERN_ERR, "can't mount with "
5342                                 "journal_async_commit in data=ordered mode");
5343                         err = -EINVAL;
5344                         goto restore_opts;
5345                 }
5346         }
5347
5348         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5349                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5350                 err = -EINVAL;
5351                 goto restore_opts;
5352         }
5353
5354         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5355                 ext4_abort(sb, "Abort forced by user");
5356
5357         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5358                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5359
5360         es = sbi->s_es;
5361
5362         if (sbi->s_journal) {
5363                 ext4_init_journal_params(sb, sbi->s_journal);
5364                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5365         }
5366
5367         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5368                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5369                         err = -EROFS;
5370                         goto restore_opts;
5371                 }
5372
5373                 if (*flags & SB_RDONLY) {
5374                         err = sync_filesystem(sb);
5375                         if (err < 0)
5376                                 goto restore_opts;
5377                         err = dquot_suspend(sb, -1);
5378                         if (err < 0)
5379                                 goto restore_opts;
5380
5381                         /*
5382                          * First of all, the unconditional stuff we have to do
5383                          * to disable replay of the journal when we next remount
5384                          */
5385                         sb->s_flags |= SB_RDONLY;
5386
5387                         /*
5388                          * OK, test if we are remounting a valid rw partition
5389                          * readonly, and if so set the rdonly flag and then
5390                          * mark the partition as valid again.
5391                          */
5392                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5393                             (sbi->s_mount_state & EXT4_VALID_FS))
5394                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5395
5396                         if (sbi->s_journal) {
5397                                 /*
5398                                  * We let remount-ro finish even if marking fs
5399                                  * as clean failed...
5400                                  */
5401                                 ext4_mark_recovery_complete(sb, es);
5402                         }
5403                         if (sbi->s_mmp_tsk)
5404                                 kthread_stop(sbi->s_mmp_tsk);
5405                 } else {
5406                         /* Make sure we can mount this feature set readwrite */
5407                         if (ext4_has_feature_readonly(sb) ||
5408                             !ext4_feature_set_ok(sb, 0)) {
5409                                 err = -EROFS;
5410                                 goto restore_opts;
5411                         }
5412                         /*
5413                          * Make sure the group descriptor checksums
5414                          * are sane.  If they aren't, refuse to remount r/w.
5415                          */
5416                         for (g = 0; g < sbi->s_groups_count; g++) {
5417                                 struct ext4_group_desc *gdp =
5418                                         ext4_get_group_desc(sb, g, NULL);
5419
5420                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5421                                         ext4_msg(sb, KERN_ERR,
5422                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5423                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5424                                                le16_to_cpu(gdp->bg_checksum));
5425                                         err = -EFSBADCRC;
5426                                         goto restore_opts;
5427                                 }
5428                         }
5429
5430                         /*
5431                          * If we have an unprocessed orphan list hanging
5432                          * around from a previously readonly bdev mount,
5433                          * require a full umount/remount for now.
5434                          */
5435                         if (es->s_last_orphan) {
5436                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5437                                        "remount RDWR because of unprocessed "
5438                                        "orphan inode list.  Please "
5439                                        "umount/remount instead");
5440                                 err = -EINVAL;
5441                                 goto restore_opts;
5442                         }
5443
5444                         /*
5445                          * Mounting a RDONLY partition read-write, so reread
5446                          * and store the current valid flag.  (It may have
5447                          * been changed by e2fsck since we originally mounted
5448                          * the partition.)
5449                          */
5450                         if (sbi->s_journal) {
5451                                 err = ext4_clear_journal_err(sb, es);
5452                                 if (err)
5453                                         goto restore_opts;
5454                         }
5455                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5456
5457                         err = ext4_setup_super(sb, es, 0);
5458                         if (err)
5459                                 goto restore_opts;
5460
5461                         sb->s_flags &= ~SB_RDONLY;
5462                         if (ext4_has_feature_mmp(sb))
5463                                 if (ext4_multi_mount_protect(sb,
5464                                                 le64_to_cpu(es->s_mmp_block))) {
5465                                         err = -EROFS;
5466                                         goto restore_opts;
5467                                 }
5468                         enable_quota = 1;
5469                 }
5470         }
5471
5472         /*
5473          * Reinitialize lazy itable initialization thread based on
5474          * current settings
5475          */
5476         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5477                 ext4_unregister_li_request(sb);
5478         else {
5479                 ext4_group_t first_not_zeroed;
5480                 first_not_zeroed = ext4_has_uninit_itable(sb);
5481                 ext4_register_li_request(sb, first_not_zeroed);
5482         }
5483
5484         /*
5485          * Handle creation of system zone data early because it can fail.
5486          * Releasing of existing data is done when we are sure remount will
5487          * succeed.
5488          */
5489         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->system_blks) {
5490                 err = ext4_setup_system_zone(sb);
5491                 if (err)
5492                         goto restore_opts;
5493         }
5494
5495         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5496                 err = ext4_commit_super(sb, 1);
5497                 if (err)
5498                         goto restore_opts;
5499         }
5500
5501 #ifdef CONFIG_QUOTA
5502         /* Release old quota file names */
5503         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5504                 kfree(old_opts.s_qf_names[i]);
5505         if (enable_quota) {
5506                 if (sb_any_quota_suspended(sb))
5507                         dquot_resume(sb, -1);
5508                 else if (ext4_has_feature_quota(sb)) {
5509                         err = ext4_enable_quotas(sb);
5510                         if (err)
5511                                 goto restore_opts;
5512                 }
5513         }
5514 #endif
5515         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->system_blks)
5516                 ext4_release_system_zone(sb);
5517
5518         /*
5519          * Some options can be enabled by ext4 and/or by VFS mount flag
5520          * either way we need to make sure it matches in both *flags and
5521          * s_flags. Copy those selected flags from s_flags to *flags
5522          */
5523         *flags = (*flags & ~vfs_flags) | (sb->s_flags & vfs_flags);
5524
5525         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5526         kfree(orig_data);
5527         return 0;
5528
5529 restore_opts:
5530         sb->s_flags = old_sb_flags;
5531         sbi->s_mount_opt = old_opts.s_mount_opt;
5532         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5533         sbi->s_resuid = old_opts.s_resuid;
5534         sbi->s_resgid = old_opts.s_resgid;
5535         sbi->s_commit_interval = old_opts.s_commit_interval;
5536         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5537         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5538         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->system_blks)
5539                 ext4_release_system_zone(sb);
5540 #ifdef CONFIG_QUOTA
5541         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5542         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5543                 to_free[i] = get_qf_name(sb, sbi, i);
5544                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
5545         }
5546         synchronize_rcu();
5547         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5548                 kfree(to_free[i]);
5549 #endif
5550         kfree(orig_data);
5551         return err;
5552 }
5553
5554 #ifdef CONFIG_QUOTA
5555 static int ext4_statfs_project(struct super_block *sb,
5556                                kprojid_t projid, struct kstatfs *buf)
5557 {
5558         struct kqid qid;
5559         struct dquot *dquot;
5560         u64 limit;
5561         u64 curblock;
5562
5563         qid = make_kqid_projid(projid);
5564         dquot = dqget(sb, qid);
5565         if (IS_ERR(dquot))
5566                 return PTR_ERR(dquot);
5567         spin_lock(&dquot->dq_dqb_lock);
5568
5569         limit = (dquot->dq_dqb.dqb_bsoftlimit ?
5570                  dquot->dq_dqb.dqb_bsoftlimit :
5571                  dquot->dq_dqb.dqb_bhardlimit) >> sb->s_blocksize_bits;
5572         if (limit && buf->f_blocks > limit) {
5573                 curblock = (dquot->dq_dqb.dqb_curspace +
5574                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5575                 buf->f_blocks = limit;
5576                 buf->f_bfree = buf->f_bavail =
5577                         (buf->f_blocks > curblock) ?
5578                          (buf->f_blocks - curblock) : 0;
5579         }
5580
5581         limit = dquot->dq_dqb.dqb_isoftlimit ?
5582                 dquot->dq_dqb.dqb_isoftlimit :
5583                 dquot->dq_dqb.dqb_ihardlimit;
5584         if (limit && buf->f_files > limit) {
5585                 buf->f_files = limit;
5586                 buf->f_ffree =
5587                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5588                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5589         }
5590
5591         spin_unlock(&dquot->dq_dqb_lock);
5592         dqput(dquot);
5593         return 0;
5594 }
5595 #endif
5596
5597 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5598 {
5599         struct super_block *sb = dentry->d_sb;
5600         struct ext4_sb_info *sbi = EXT4_SB(sb);
5601         struct ext4_super_block *es = sbi->s_es;
5602         ext4_fsblk_t overhead = 0, resv_blocks;
5603         u64 fsid;
5604         s64 bfree;
5605         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5606
5607         if (!test_opt(sb, MINIX_DF))
5608                 overhead = sbi->s_overhead;
5609
5610         buf->f_type = EXT4_SUPER_MAGIC;
5611         buf->f_bsize = sb->s_blocksize;
5612         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5613         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5614                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5615         /* prevent underflow in case that few free space is available */
5616         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5617         buf->f_bavail = buf->f_bfree -
5618                         (ext4_r_blocks_count(es) + resv_blocks);
5619         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5620                 buf->f_bavail = 0;
5621         buf->f_files = le32_to_cpu(es->s_inodes_count);
5622         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5623         buf->f_namelen = EXT4_NAME_LEN;
5624         fsid = le64_to_cpup((void *)es->s_uuid) ^
5625                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5626         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5627         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5628
5629 #ifdef CONFIG_QUOTA
5630         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5631             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5632                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5633 #endif
5634         return 0;
5635 }
5636
5637
5638 #ifdef CONFIG_QUOTA
5639
5640 /*
5641  * Helper functions so that transaction is started before we acquire dqio_sem
5642  * to keep correct lock ordering of transaction > dqio_sem
5643  */
5644 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5645 {
5646         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5647 }
5648
5649 static int ext4_write_dquot(struct dquot *dquot)
5650 {
5651         int ret, err;
5652         handle_t *handle;
5653         struct inode *inode;
5654
5655         inode = dquot_to_inode(dquot);
5656         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5657                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5658         if (IS_ERR(handle))
5659                 return PTR_ERR(handle);
5660         ret = dquot_commit(dquot);
5661         err = ext4_journal_stop(handle);
5662         if (!ret)
5663                 ret = err;
5664         return ret;
5665 }
5666
5667 static int ext4_acquire_dquot(struct dquot *dquot)
5668 {
5669         int ret, err;
5670         handle_t *handle;
5671
5672         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5673                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5674         if (IS_ERR(handle))
5675                 return PTR_ERR(handle);
5676         ret = dquot_acquire(dquot);
5677         err = ext4_journal_stop(handle);
5678         if (!ret)
5679                 ret = err;
5680         return ret;
5681 }
5682
5683 static int ext4_release_dquot(struct dquot *dquot)
5684 {
5685         int ret, err;
5686         handle_t *handle;
5687
5688         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5689                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5690         if (IS_ERR(handle)) {
5691                 /* Release dquot anyway to avoid endless cycle in dqput() */
5692                 dquot_release(dquot);
5693                 return PTR_ERR(handle);
5694         }
5695         ret = dquot_release(dquot);
5696         err = ext4_journal_stop(handle);
5697         if (!ret)
5698                 ret = err;
5699         return ret;
5700 }
5701
5702 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5703 {
5704         struct super_block *sb = dquot->dq_sb;
5705         struct ext4_sb_info *sbi = EXT4_SB(sb);
5706
5707         /* Are we journaling quotas? */
5708         if (ext4_has_feature_quota(sb) ||
5709             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5710                 dquot_mark_dquot_dirty(dquot);
5711                 return ext4_write_dquot(dquot);
5712         } else {
5713                 return dquot_mark_dquot_dirty(dquot);
5714         }
5715 }
5716
5717 static int ext4_write_info(struct super_block *sb, int type)
5718 {
5719         int ret, err;
5720         handle_t *handle;
5721
5722         /* Data block + inode block */
5723         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5724         if (IS_ERR(handle))
5725                 return PTR_ERR(handle);
5726         ret = dquot_commit_info(sb, type);
5727         err = ext4_journal_stop(handle);
5728         if (!ret)
5729                 ret = err;
5730         return ret;
5731 }
5732
5733 /*
5734  * Turn on quotas during mount time - we need to find
5735  * the quota file and such...
5736  */
5737 static int ext4_quota_on_mount(struct super_block *sb, int type)
5738 {
5739         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
5740                                         EXT4_SB(sb)->s_jquota_fmt, type);
5741 }
5742
5743 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5744 {
5745         struct ext4_inode_info *ei = EXT4_I(inode);
5746
5747         /* The first argument of lockdep_set_subclass has to be
5748          * *exactly* the same as the argument to init_rwsem() --- in
5749          * this case, in init_once() --- or lockdep gets unhappy
5750          * because the name of the lock is set using the
5751          * stringification of the argument to init_rwsem().
5752          */
5753         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
5754         lockdep_set_subclass(&ei->i_data_sem, subclass);
5755 }
5756
5757 /*
5758  * Standard function to be called on quota_on
5759  */
5760 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5761                          const struct path *path)
5762 {
5763         int err;
5764
5765         if (!test_opt(sb, QUOTA))
5766                 return -EINVAL;
5767
5768         /* Quotafile not on the same filesystem? */
5769         if (path->dentry->d_sb != sb)
5770                 return -EXDEV;
5771
5772         /* Quota already enabled for this file? */
5773         if (IS_NOQUOTA(d_inode(path->dentry)))
5774                 return -EBUSY;
5775
5776         /* Journaling quota? */
5777         if (EXT4_SB(sb)->s_qf_names[type]) {
5778                 /* Quotafile not in fs root? */
5779                 if (path->dentry->d_parent != sb->s_root)
5780                         ext4_msg(sb, KERN_WARNING,
5781                                 "Quota file not on filesystem root. "
5782                                 "Journaled quota will not work");
5783                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5784         } else {
5785                 /*
5786                  * Clear the flag just in case mount options changed since
5787                  * last time.
5788                  */
5789                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5790         }
5791
5792         /*
5793          * When we journal data on quota file, we have to flush journal to see
5794          * all updates to the file when we bypass pagecache...
5795          */
5796         if (EXT4_SB(sb)->s_journal &&
5797             ext4_should_journal_data(d_inode(path->dentry))) {
5798                 /*
5799                  * We don't need to lock updates but journal_flush() could
5800                  * otherwise be livelocked...
5801                  */
5802                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5803                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5804                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5805                 if (err)
5806                         return err;
5807         }
5808
5809         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5810         err = dquot_quota_on(sb, type, format_id, path);
5811         if (!err) {
5812                 struct inode *inode = d_inode(path->dentry);
5813                 handle_t *handle;
5814
5815                 /*
5816                  * Set inode flags to prevent userspace from messing with quota
5817                  * files. If this fails, we return success anyway since quotas
5818                  * are already enabled and this is not a hard failure.
5819                  */
5820                 inode_lock(inode);
5821                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5822                 if (IS_ERR(handle))
5823                         goto unlock_inode;
5824                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5825                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5826                                 S_NOATIME | S_IMMUTABLE);
5827                 ext4_mark_inode_dirty(handle, inode);
5828                 ext4_journal_stop(handle);
5829         unlock_inode:
5830                 inode_unlock(inode);
5831                 if (err)
5832                         dquot_quota_off(sb, type);
5833         }
5834         if (err)
5835                 lockdep_set_quota_inode(path->dentry->d_inode,
5836                                              I_DATA_SEM_NORMAL);
5837         return err;
5838 }
5839
5840 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5841                              unsigned int flags)
5842 {
5843         int err;
5844         struct inode *qf_inode;
5845         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5846                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5847                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5848                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5849         };
5850
5851         BUG_ON(!ext4_has_feature_quota(sb));
5852
5853         if (!qf_inums[type])
5854                 return -EPERM;
5855
5856         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
5857         if (IS_ERR(qf_inode)) {
5858                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5859                 return PTR_ERR(qf_inode);
5860         }
5861
5862         /* Don't account quota for quota files to avoid recursion */
5863         qf_inode->i_flags |= S_NOQUOTA;
5864         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5865         err = dquot_enable(qf_inode, type, format_id, flags);
5866         if (err)
5867                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5868         iput(qf_inode);
5869
5870         return err;
5871 }
5872
5873 /* Enable usage tracking for all quota types. */
5874 static int ext4_enable_quotas(struct super_block *sb)
5875 {
5876         int type, err = 0;
5877         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5878                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5879                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5880                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5881         };
5882         bool quota_mopt[EXT4_MAXQUOTAS] = {
5883                 test_opt(sb, USRQUOTA),
5884                 test_opt(sb, GRPQUOTA),
5885                 test_opt(sb, PRJQUOTA),
5886         };
5887
5888         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
5889         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5890                 if (qf_inums[type]) {
5891                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5892                                 DQUOT_USAGE_ENABLED |
5893                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5894                         if (err) {
5895                                 ext4_warning(sb,
5896                                         "Failed to enable quota tracking "
5897                                         "(type=%d, err=%d). Please run "
5898                                         "e2fsck to fix.", type, err);
5899                                 for (type--; type >= 0; type--) {
5900                                         struct inode *inode;
5901
5902                                         inode = sb_dqopt(sb)->files[type];
5903                                         if (inode)
5904                                                 inode = igrab(inode);
5905                                         dquot_quota_off(sb, type);
5906                                         if (inode) {
5907                                                 lockdep_set_quota_inode(inode,
5908                                                         I_DATA_SEM_NORMAL);
5909                                                 iput(inode);
5910                                         }
5911                                 }
5912
5913                                 return err;
5914                         }
5915                 }
5916         }
5917         return 0;
5918 }
5919
5920 static int ext4_quota_off(struct super_block *sb, int type)
5921 {
5922         struct inode *inode = sb_dqopt(sb)->files[type];
5923         handle_t *handle;
5924         int err;
5925
5926         /* Force all delayed allocation blocks to be allocated.
5927          * Caller already holds s_umount sem */
5928         if (test_opt(sb, DELALLOC))
5929                 sync_filesystem(sb);
5930
5931         if (!inode || !igrab(inode))
5932                 goto out;
5933
5934         err = dquot_quota_off(sb, type);
5935         if (err || ext4_has_feature_quota(sb))
5936                 goto out_put;
5937
5938         inode_lock(inode);
5939         /*
5940          * Update modification times of quota files when userspace can
5941          * start looking at them. If we fail, we return success anyway since
5942          * this is not a hard failure and quotas are already disabled.
5943          */
5944         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5945         if (IS_ERR(handle))
5946                 goto out_unlock;
5947         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
5948         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
5949         inode->i_mtime = inode->i_ctime = current_time(inode);
5950         ext4_mark_inode_dirty(handle, inode);
5951         ext4_journal_stop(handle);
5952 out_unlock:
5953         inode_unlock(inode);
5954 out_put:
5955         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
5956         iput(inode);
5957         return err;
5958 out:
5959         return dquot_quota_off(sb, type);
5960 }
5961
5962 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5963  * acquiring the locks... As quota files are never truncated and quota code
5964  * itself serializes the operations (and no one else should touch the files)
5965  * we don't have to be afraid of races */
5966 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5967                                size_t len, loff_t off)
5968 {
5969         struct inode *inode = sb_dqopt(sb)->files[type];
5970         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5971         int offset = off & (sb->s_blocksize - 1);
5972         int tocopy;
5973         size_t toread;
5974         struct buffer_head *bh;
5975         loff_t i_size = i_size_read(inode);
5976
5977         if (off > i_size)
5978                 return 0;
5979         if (off+len > i_size)
5980                 len = i_size-off;
5981         toread = len;
5982         while (toread > 0) {
5983                 tocopy = sb->s_blocksize - offset < toread ?
5984                                 sb->s_blocksize - offset : toread;
5985                 bh = ext4_bread(NULL, inode, blk, 0);
5986                 if (IS_ERR(bh))
5987                         return PTR_ERR(bh);
5988                 if (!bh)        /* A hole? */
5989                         memset(data, 0, tocopy);
5990                 else
5991                         memcpy(data, bh->b_data+offset, tocopy);
5992                 brelse(bh);
5993                 offset = 0;
5994                 toread -= tocopy;
5995                 data += tocopy;
5996                 blk++;
5997         }
5998         return len;
5999 }
6000
6001 /* Write to quotafile (we know the transaction is already started and has
6002  * enough credits) */
6003 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6004                                 const char *data, size_t len, loff_t off)
6005 {
6006         struct inode *inode = sb_dqopt(sb)->files[type];
6007         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6008         int err, offset = off & (sb->s_blocksize - 1);
6009         int retries = 0;
6010         struct buffer_head *bh;
6011         handle_t *handle = journal_current_handle();
6012
6013         if (!handle) {
6014                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6015                         " cancelled because transaction is not started",
6016                         (unsigned long long)off, (unsigned long long)len);
6017                 return -EIO;
6018         }
6019         /*
6020          * Since we account only one data block in transaction credits,
6021          * then it is impossible to cross a block boundary.
6022          */
6023         if (sb->s_blocksize - offset < len) {
6024                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6025                         " cancelled because not block aligned",
6026                         (unsigned long long)off, (unsigned long long)len);
6027                 return -EIO;
6028         }
6029
6030         do {
6031                 bh = ext4_bread(handle, inode, blk,
6032                                 EXT4_GET_BLOCKS_CREATE |
6033                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6034         } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
6035                  ext4_should_retry_alloc(inode->i_sb, &retries));
6036         if (IS_ERR(bh))
6037                 return PTR_ERR(bh);
6038         if (!bh)
6039                 goto out;
6040         BUFFER_TRACE(bh, "get write access");
6041         err = ext4_journal_get_write_access(handle, bh);
6042         if (err) {
6043                 brelse(bh);
6044                 return err;
6045         }
6046         lock_buffer(bh);
6047         memcpy(bh->b_data+offset, data, len);
6048         flush_dcache_page(bh->b_page);
6049         unlock_buffer(bh);
6050         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6051         brelse(bh);
6052 out:
6053         if (inode->i_size < off + len) {
6054                 i_size_write(inode, off + len);
6055                 EXT4_I(inode)->i_disksize = inode->i_size;
6056                 ext4_mark_inode_dirty(handle, inode);
6057         }
6058         return len;
6059 }
6060
6061 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid)
6062 {
6063         const struct quota_format_ops   *ops;
6064
6065         if (!sb_has_quota_loaded(sb, qid->type))
6066                 return -ESRCH;
6067         ops = sb_dqopt(sb)->ops[qid->type];
6068         if (!ops || !ops->get_next_id)
6069                 return -ENOSYS;
6070         return dquot_get_next_id(sb, qid);
6071 }
6072 #endif
6073
6074 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6075                        const char *dev_name, void *data)
6076 {
6077         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6078 }
6079
6080 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6081 static inline void register_as_ext2(void)
6082 {
6083         int err = register_filesystem(&ext2_fs_type);
6084         if (err)
6085                 printk(KERN_WARNING
6086                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6087 }
6088
6089 static inline void unregister_as_ext2(void)
6090 {
6091         unregister_filesystem(&ext2_fs_type);
6092 }
6093
6094 static inline int ext2_feature_set_ok(struct super_block *sb)
6095 {
6096         if (ext4_has_unknown_ext2_incompat_features(sb))
6097                 return 0;
6098         if (sb_rdonly(sb))
6099                 return 1;
6100         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6101                 return 0;
6102         return 1;
6103 }
6104 #else
6105 static inline void register_as_ext2(void) { }
6106 static inline void unregister_as_ext2(void) { }
6107 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6108 #endif
6109
6110 static inline void register_as_ext3(void)
6111 {
6112         int err = register_filesystem(&ext3_fs_type);
6113         if (err)
6114                 printk(KERN_WARNING
6115                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6116 }
6117
6118 static inline void unregister_as_ext3(void)
6119 {
6120         unregister_filesystem(&ext3_fs_type);
6121 }
6122
6123 static inline int ext3_feature_set_ok(struct super_block *sb)
6124 {
6125         if (ext4_has_unknown_ext3_incompat_features(sb))
6126                 return 0;
6127         if (!ext4_has_feature_journal(sb))
6128                 return 0;
6129         if (sb_rdonly(sb))
6130                 return 1;
6131         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6132                 return 0;
6133         return 1;
6134 }
6135
6136 static struct file_system_type ext4_fs_type = {
6137         .owner          = THIS_MODULE,
6138         .name           = "ext4",
6139         .mount          = ext4_mount,
6140         .kill_sb        = kill_block_super,
6141         .fs_flags       = FS_REQUIRES_DEV,
6142 };
6143 MODULE_ALIAS_FS("ext4");
6144
6145 /* Shared across all ext4 file systems */
6146 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6147
6148 static int __init ext4_init_fs(void)
6149 {
6150         int i, err;
6151
6152         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6153         ext4_li_info = NULL;
6154         mutex_init(&ext4_li_mtx);
6155
6156         /* Build-time check for flags consistency */
6157         ext4_check_flag_values();
6158
6159         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6160                 init_waitqueue_head(&ext4__ioend_wq[i]);
6161
6162         err = ext4_init_es();
6163         if (err)
6164                 return err;
6165
6166         err = ext4_init_pageio();
6167         if (err)
6168                 goto out5;
6169
6170         err = ext4_init_system_zone();
6171         if (err)
6172                 goto out4;
6173
6174         err = ext4_init_sysfs();
6175         if (err)
6176                 goto out3;
6177
6178         err = ext4_init_mballoc();
6179         if (err)
6180                 goto out2;
6181         err = init_inodecache();
6182         if (err)
6183                 goto out1;
6184         register_as_ext3();
6185         register_as_ext2();
6186         err = register_filesystem(&ext4_fs_type);
6187         if (err)
6188                 goto out;
6189
6190         return 0;
6191 out:
6192         unregister_as_ext2();
6193         unregister_as_ext3();
6194         destroy_inodecache();
6195 out1:
6196         ext4_exit_mballoc();
6197 out2:
6198         ext4_exit_sysfs();
6199 out3:
6200         ext4_exit_system_zone();
6201 out4:
6202         ext4_exit_pageio();
6203 out5:
6204         ext4_exit_es();
6205
6206         return err;
6207 }
6208
6209 static void __exit ext4_exit_fs(void)
6210 {
6211         ext4_destroy_lazyinit_thread();
6212         unregister_as_ext2();
6213         unregister_as_ext3();
6214         unregister_filesystem(&ext4_fs_type);
6215         destroy_inodecache();
6216         ext4_exit_mballoc();
6217         ext4_exit_sysfs();
6218         ext4_exit_system_zone();
6219         ext4_exit_pageio();
6220         ext4_exit_es();
6221 }
6222
6223 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6224 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6225 MODULE_LICENSE("GPL");
6226 MODULE_SOFTDEP("pre: crc32c");
6227 module_init(ext4_init_fs)
6228 module_exit(ext4_exit_fs)