fs/ext4/super.c

   1 /*
   2  *  linux/fs/ext4/super.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/inode.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Big-endian to little-endian byte-swapping/bitmaps by
  16  *        David S. Miller (davem@caip.rutgers.edu), 1995
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/string.h>
  21 #include <linux/fs.h>
  22 #include <linux/time.h>
  23 #include <linux/vmalloc.h>
  24 #include <linux/slab.h>
  25 #include <linux/init.h>
  26 #include <linux/blkdev.h>
  27 #include <linux/backing-dev.h>
  28 #include <linux/parser.h>
  29 #include <linux/buffer_head.h>
  30 #include <linux/exportfs.h>
  31 #include <linux/vfs.h>
  32 #include <linux/random.h>
  33 #include <linux/mount.h>
  34 #include <linux/namei.h>
  35 #include <linux/quotaops.h>
  36 #include <linux/seq_file.h>
  37 #include <linux/ctype.h>
  38 #include <linux/log2.h>
  39 #include <linux/crc16.h>
  40 #include <linux/cleancache.h>
  41 #include <asm/uaccess.h>
  42
  43 #include <linux/kthread.h>
  44 #include <linux/freezer.h>
  45
  46 #include "ext4.h"
  47 #include "ext4_extents.h"       /* Needed for trace points definition */
  48 #include "ext4_jbd2.h"
  49 #include "xattr.h"
  50 #include "acl.h"
  51 #include "mballoc.h"
  52
  53 #define CREATE_TRACE_POINTS
  54 #include <trace/events/ext4.h>
  55
  56 static struct ext4_lazy_init *ext4_li_info;
  57 static struct mutex ext4_li_mtx;
  58 static int ext4_mballoc_ready;
  59 static struct ratelimit_state ext4_mount_msg_ratelimit;
  60
  61 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  62                              unsigned long journal_devnum);
  63 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  64 static int ext4_commit_super(struct super_block *sb, int sync);
  65 static void ext4_mark_recovery_complete(struct super_block *sb,
  66                                         struct ext4_super_block *es);
  67 static void ext4_clear_journal_err(struct super_block *sb,
  68                                    struct ext4_super_block *es);
  69 static int ext4_sync_fs(struct super_block *sb, int wait);
  70 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  71 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  72 static int ext4_unfreeze(struct super_block *sb);
  73 static int ext4_freeze(struct super_block *sb);
  74 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  75                        const char *dev_name, void *data);
  76 static inline int ext2_feature_set_ok(struct super_block *sb);
  77 static inline int ext3_feature_set_ok(struct super_block *sb);
  78 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  79 static void ext4_destroy_lazyinit_thread(void);
  80 static void ext4_unregister_li_request(struct super_block *sb);
  81 static void ext4_clear_request_list(void);
  82
  83 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
  84 static struct file_system_type ext2_fs_type = {
  85         .owner          = THIS_MODULE,
  86         .name           = "ext2",
  87         .mount          = ext4_mount,
  88         .kill_sb        = kill_block_super,
  89         .fs_flags       = FS_REQUIRES_DEV,
  90 };
  91 MODULE_ALIAS_FS("ext2");
  92 MODULE_ALIAS("ext2");
  93 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
  94 #else
  95 #define IS_EXT2_SB(sb) (0)
  96 #endif
  97
  98
  99 static struct file_system_type ext3_fs_type = {
 100         .owner          = THIS_MODULE,
 101         .name           = "ext3",
 102         .mount          = ext4_mount,
 103         .kill_sb        = kill_block_super,
 104         .fs_flags       = FS_REQUIRES_DEV,
 105 };
 106 MODULE_ALIAS_FS("ext3");
 107 MODULE_ALIAS("ext3");
 108 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 109
 110 static int ext4_verify_csum_type(struct super_block *sb,
 111                                  struct ext4_super_block *es)
 112 {
 113         if (!ext4_has_feature_metadata_csum(sb))
 114                 return 1;
 115
 116         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 117 }
 118
 119 static __le32 ext4_superblock_csum(struct super_block *sb,
 120                                    struct ext4_super_block *es)
 121 {
 122         struct ext4_sb_info *sbi = EXT4_SB(sb);
 123         int offset = offsetof(struct ext4_super_block, s_checksum);
 124         __u32 csum;
 125
 126         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 127
 128         return cpu_to_le32(csum);
 129 }
 130
 131 static int ext4_superblock_csum_verify(struct super_block *sb,
 132                                        struct ext4_super_block *es)
 133 {
 134         if (!ext4_has_metadata_csum(sb))
 135                 return 1;
 136
 137         return es->s_checksum == ext4_superblock_csum(sb, es);
 138 }
 139
 140 void ext4_superblock_csum_set(struct super_block *sb)
 141 {
 142         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 143
 144         if (!ext4_has_metadata_csum(sb))
 145                 return;
 146
 147         es->s_checksum = ext4_superblock_csum(sb, es);
 148 }
 149
 150 void *ext4_kvmalloc(size_t size, gfp_t flags)
 151 {
 152         void *ret;
 153
 154         ret = kmalloc(size, flags | __GFP_NOWARN);
 155         if (!ret)
 156                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 157         return ret;
 158 }
 159
 160 void *ext4_kvzalloc(size_t size, gfp_t flags)
 161 {
 162         void *ret;
 163
 164         ret = kzalloc(size, flags | __GFP_NOWARN);
 165         if (!ret)
 166                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 167         return ret;
 168 }
 169
 170 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 171                                struct ext4_group_desc *bg)
 172 {
 173         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 174                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 175                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 176 }
 177
 178 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 179                                struct ext4_group_desc *bg)
 180 {
 181         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 182                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 183                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 184 }
 185
 186 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 187                               struct ext4_group_desc *bg)
 188 {
 189         return le32_to_cpu(bg->bg_inode_table_lo) |
 190                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 191                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 192 }
 193
 194 __u32 ext4_free_group_clusters(struct super_block *sb,
 195                                struct ext4_group_desc *bg)
 196 {
 197         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 198                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 199                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 200 }
 201
 202 __u32 ext4_free_inodes_count(struct super_block *sb,
 203                               struct ext4_group_desc *bg)
 204 {
 205         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 206                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 207                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 208 }
 209
 210 __u32 ext4_used_dirs_count(struct super_block *sb,
 211                               struct ext4_group_desc *bg)
 212 {
 213         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 214                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 215                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 216 }
 217
 218 __u32 ext4_itable_unused_count(struct super_block *sb,
 219                               struct ext4_group_desc *bg)
 220 {
 221         return le16_to_cpu(bg->bg_itable_unused_lo) |
 222                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 223                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 224 }
 225
 226 void ext4_block_bitmap_set(struct super_block *sb,
 227                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 228 {
 229         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 230         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 231                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 232 }
 233
 234 void ext4_inode_bitmap_set(struct super_block *sb,
 235                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 236 {
 237         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 238         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 239                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 240 }
 241
 242 void ext4_inode_table_set(struct super_block *sb,
 243                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 244 {
 245         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 246         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 247                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 248 }
 249
 250 void ext4_free_group_clusters_set(struct super_block *sb,
 251                                   struct ext4_group_desc *bg, __u32 count)
 252 {
 253         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 254         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 255                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 256 }
 257
 258 void ext4_free_inodes_set(struct super_block *sb,
 259                           struct ext4_group_desc *bg, __u32 count)
 260 {
 261         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 262         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 263                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 264 }
 265
 266 void ext4_used_dirs_set(struct super_block *sb,
 267                           struct ext4_group_desc *bg, __u32 count)
 268 {
 269         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 270         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 271                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 272 }
 273
 274 void ext4_itable_unused_set(struct super_block *sb,
 275                           struct ext4_group_desc *bg, __u32 count)
 276 {
 277         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 278         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 279                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 280 }
 281
 282
 283 static void __save_error_info(struct super_block *sb, const char *func,
 284                             unsigned int line)
 285 {
 286         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 287
 288         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 289         if (bdev_read_only(sb->s_bdev))
 290                 return;
 291         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 292         es->s_last_error_time = cpu_to_le32(get_seconds());
 293         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 294         es->s_last_error_line = cpu_to_le32(line);
 295         if (!es->s_first_error_time) {
 296                 es->s_first_error_time = es->s_last_error_time;
 297                 strncpy(es->s_first_error_func, func,
 298                         sizeof(es->s_first_error_func));
 299                 es->s_first_error_line = cpu_to_le32(line);
 300                 es->s_first_error_ino = es->s_last_error_ino;
 301                 es->s_first_error_block = es->s_last_error_block;
 302         }
 303         /*
 304          * Start the daily error reporting function if it hasn't been
 305          * started already
 306          */
 307         if (!es->s_error_count)
 308                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 309         le32_add_cpu(&es->s_error_count, 1);
 310 }
 311
 312 static void save_error_info(struct super_block *sb, const char *func,
 313                             unsigned int line)
 314 {
 315         __save_error_info(sb, func, line);
 316         ext4_commit_super(sb, 1);
 317 }
 318
 319 /*
 320  * The del_gendisk() function uninitializes the disk-specific data
 321  * structures, including the bdi structure, without telling anyone
 322  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 323  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 324  * This is a kludge to prevent these oops until we can put in a proper
 325  * hook in del_gendisk() to inform the VFS and file system layers.
 326  */
 327 static int block_device_ejected(struct super_block *sb)
 328 {
 329         struct inode *bd_inode = sb->s_bdev->bd_inode;
 330         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 331
 332         return bdi->dev == NULL;
 333 }
 334
 335 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 336 {
 337         struct super_block              *sb = journal->j_private;
 338         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 339         int                             error = is_journal_aborted(journal);
 340         struct ext4_journal_cb_entry    *jce;
 341
 342         BUG_ON(txn->t_state == T_FINISHED);
 343         spin_lock(&sbi->s_md_lock);
 344         while (!list_empty(&txn->t_private_list)) {
 345                 jce = list_entry(txn->t_private_list.next,
 346                                  struct ext4_journal_cb_entry, jce_list);
 347                 list_del_init(&jce->jce_list);
 348                 spin_unlock(&sbi->s_md_lock);
 349                 jce->jce_func(sb, jce, error);
 350                 spin_lock(&sbi->s_md_lock);
 351         }
 352         spin_unlock(&sbi->s_md_lock);
 353 }
 354
 355 /* Deal with the reporting of failure conditions on a filesystem such as
 356  * inconsistencies detected or read IO failures.
 357  *
 358  * On ext2, we can store the error state of the filesystem in the
 359  * superblock.  That is not possible on ext4, because we may have other
 360  * write ordering constraints on the superblock which prevent us from
 361  * writing it out straight away; and given that the journal is about to
 362  * be aborted, we can't rely on the current, or future, transactions to
 363  * write out the superblock safely.
 364  *
 365  * We'll just use the jbd2_journal_abort() error code to record an error in
 366  * the journal instead.  On recovery, the journal will complain about
 367  * that error until we've noted it down and cleared it.
 368  */
 369
 370 static void ext4_handle_error(struct super_block *sb)
 371 {
 372         if (sb->s_flags & MS_RDONLY)
 373                 return;
 374
 375         if (!test_opt(sb, ERRORS_CONT)) {
 376                 journal_t *journal = EXT4_SB(sb)->s_journal;
 377
 378                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 379                 if (journal)
 380                         jbd2_journal_abort(journal, -EIO);
 381         }
 382         if (test_opt(sb, ERRORS_RO)) {
 383                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 384                 /*
 385                  * Make sure updated value of ->s_mount_flags will be visible
 386                  * before ->s_flags update
 387                  */
 388                 smp_wmb();
 389                 sb->s_flags |= MS_RDONLY;
 390         }
 391         if (test_opt(sb, ERRORS_PANIC)) {
 392                 if (EXT4_SB(sb)->s_journal &&
 393                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 394                         return;
 395                 panic("EXT4-fs (device %s): panic forced after error\n",
 396                         sb->s_id);
 397         }
 398 }
 399
 400 #define ext4_error_ratelimit(sb)                                        \
 401                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 402                              "EXT4-fs error")
 403
 404 void __ext4_error(struct super_block *sb, const char *function,
 405                   unsigned int line, const char *fmt, ...)
 406 {
 407         struct va_format vaf;
 408         va_list args;
 409
 410         if (ext4_error_ratelimit(sb)) {
 411                 va_start(args, fmt);
 412                 vaf.fmt = fmt;
 413                 vaf.va = &args;
 414                 printk(KERN_CRIT
 415                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 416                        sb->s_id, function, line, current->comm, &vaf);
 417                 va_end(args);
 418         }
 419         save_error_info(sb, function, line);
 420         ext4_handle_error(sb);
 421 }
 422
 423 void __ext4_error_inode(struct inode *inode, const char *function,
 424                         unsigned int line, ext4_fsblk_t block,
 425                         const char *fmt, ...)
 426 {
 427         va_list args;
 428         struct va_format vaf;
 429         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 430
 431         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 432         es->s_last_error_block = cpu_to_le64(block);
 433         if (ext4_error_ratelimit(inode->i_sb)) {
 434                 va_start(args, fmt);
 435                 vaf.fmt = fmt;
 436                 vaf.va = &args;
 437                 if (block)
 438                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 439                                "inode #%lu: block %llu: comm %s: %pV\n",
 440                                inode->i_sb->s_id, function, line, inode->i_ino,
 441                                block, current->comm, &vaf);
 442                 else
 443                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 444                                "inode #%lu: comm %s: %pV\n",
 445                                inode->i_sb->s_id, function, line, inode->i_ino,
 446                                current->comm, &vaf);
 447                 va_end(args);
 448         }
 449         save_error_info(inode->i_sb, function, line);
 450         ext4_handle_error(inode->i_sb);
 451 }
 452
 453 void __ext4_error_file(struct file *file, const char *function,
 454                        unsigned int line, ext4_fsblk_t block,
 455                        const char *fmt, ...)
 456 {
 457         va_list args;
 458         struct va_format vaf;
 459         struct ext4_super_block *es;
 460         struct inode *inode = file_inode(file);
 461         char pathname[80], *path;
 462
 463         es = EXT4_SB(inode->i_sb)->s_es;
 464         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 465         if (ext4_error_ratelimit(inode->i_sb)) {
 466                 path = file_path(file, pathname, sizeof(pathname));
 467                 if (IS_ERR(path))
 468                         path = "(unknown)";
 469                 va_start(args, fmt);
 470                 vaf.fmt = fmt;
 471                 vaf.va = &args;
 472                 if (block)
 473                         printk(KERN_CRIT
 474                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 475                                "block %llu: comm %s: path %s: %pV\n",
 476                                inode->i_sb->s_id, function, line, inode->i_ino,
 477                                block, current->comm, path, &vaf);
 478                 else
 479                         printk(KERN_CRIT
 480                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 481                                "comm %s: path %s: %pV\n",
 482                                inode->i_sb->s_id, function, line, inode->i_ino,
 483                                current->comm, path, &vaf);
 484                 va_end(args);
 485         }
 486         save_error_info(inode->i_sb, function, line);
 487         ext4_handle_error(inode->i_sb);
 488 }
 489
 490 const char *ext4_decode_error(struct super_block *sb, int errno,
 491                               char nbuf[16])
 492 {
 493         char *errstr = NULL;
 494
 495         switch (errno) {
 496         case -EFSCORRUPTED:
 497                 errstr = "Corrupt filesystem";
 498                 break;
 499         case -EFSBADCRC:
 500                 errstr = "Filesystem failed CRC";
 501                 break;
 502         case -EIO:
 503                 errstr = "IO failure";
 504                 break;
 505         case -ENOMEM:
 506                 errstr = "Out of memory";
 507                 break;
 508         case -EROFS:
 509                 if (!sb || (EXT4_SB(sb)->s_journal &&
 510                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 511                         errstr = "Journal has aborted";
 512                 else
 513                         errstr = "Readonly filesystem";
 514                 break;
 515         default:
 516                 /* If the caller passed in an extra buffer for unknown
 517                  * errors, textualise them now.  Else we just return
 518                  * NULL. */
 519                 if (nbuf) {
 520                         /* Check for truncated error codes... */
 521                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 522                                 errstr = nbuf;
 523                 }
 524                 break;
 525         }
 526
 527         return errstr;
 528 }
 529
 530 /* __ext4_std_error decodes expected errors from journaling functions
 531  * automatically and invokes the appropriate error response.  */
 532
 533 void __ext4_std_error(struct super_block *sb, const char *function,
 534                       unsigned int line, int errno)
 535 {
 536         char nbuf[16];
 537         const char *errstr;
 538
 539         /* Special case: if the error is EROFS, and we're not already
 540          * inside a transaction, then there's really no point in logging
 541          * an error. */
 542         if (errno == -EROFS && journal_current_handle() == NULL &&
 543             (sb->s_flags & MS_RDONLY))
 544                 return;
 545
 546         if (ext4_error_ratelimit(sb)) {
 547                 errstr = ext4_decode_error(sb, errno, nbuf);
 548                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 549                        sb->s_id, function, line, errstr);
 550         }
 551
 552         save_error_info(sb, function, line);
 553         ext4_handle_error(sb);
 554 }
 555
 556 /*
 557  * ext4_abort is a much stronger failure handler than ext4_error.  The
 558  * abort function may be used to deal with unrecoverable failures such
 559  * as journal IO errors or ENOMEM at a critical moment in log management.
 560  *
 561  * We unconditionally force the filesystem into an ABORT|READONLY state,
 562  * unless the error response on the fs has been set to panic in which
 563  * case we take the easy way out and panic immediately.
 564  */
 565
 566 void __ext4_abort(struct super_block *sb, const char *function,
 567                 unsigned int line, const char *fmt, ...)
 568 {
 569         va_list args;
 570
 571         save_error_info(sb, function, line);
 572         va_start(args, fmt);
 573         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
 574                function, line);
 575         vprintk(fmt, args);
 576         printk("\n");
 577         va_end(args);
 578
 579         if ((sb->s_flags & MS_RDONLY) == 0) {
 580                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 581                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 582                 /*
 583                  * Make sure updated value of ->s_mount_flags will be visible
 584                  * before ->s_flags update
 585                  */
 586                 smp_wmb();
 587                 sb->s_flags |= MS_RDONLY;
 588                 if (EXT4_SB(sb)->s_journal)
 589                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 590                 save_error_info(sb, function, line);
 591         }
 592         if (test_opt(sb, ERRORS_PANIC)) {
 593                 if (EXT4_SB(sb)->s_journal &&
 594                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 595                         return;
 596                 panic("EXT4-fs panic from previous error\n");
 597         }
 598 }
 599
 600 void __ext4_msg(struct super_block *sb,
 601                 const char *prefix, const char *fmt, ...)
 602 {
 603         struct va_format vaf;
 604         va_list args;
 605
 606         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 607                 return;
 608
 609         va_start(args, fmt);
 610         vaf.fmt = fmt;
 611         vaf.va = &args;
 612         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 613         va_end(args);
 614 }
 615
 616 #define ext4_warning_ratelimit(sb)                                      \
 617                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 618                              "EXT4-fs warning")
 619
 620 void __ext4_warning(struct super_block *sb, const char *function,
 621                     unsigned int line, const char *fmt, ...)
 622 {
 623         struct va_format vaf;
 624         va_list args;
 625
 626         if (!ext4_warning_ratelimit(sb))
 627                 return;
 628
 629         va_start(args, fmt);
 630         vaf.fmt = fmt;
 631         vaf.va = &args;
 632         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 633                sb->s_id, function, line, &vaf);
 634         va_end(args);
 635 }
 636
 637 void __ext4_warning_inode(const struct inode *inode, const char *function,
 638                           unsigned int line, const char *fmt, ...)
 639 {
 640         struct va_format vaf;
 641         va_list args;
 642
 643         if (!ext4_warning_ratelimit(inode->i_sb))
 644                 return;
 645
 646         va_start(args, fmt);
 647         vaf.fmt = fmt;
 648         vaf.va = &args;
 649         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 650                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 651                function, line, inode->i_ino, current->comm, &vaf);
 652         va_end(args);
 653 }
 654
 655 void __ext4_grp_locked_error(const char *function, unsigned int line,
 656                              struct super_block *sb, ext4_group_t grp,
 657                              unsigned long ino, ext4_fsblk_t block,
 658                              const char *fmt, ...)
 659 __releases(bitlock)
 660 __acquires(bitlock)
 661 {
 662         struct va_format vaf;
 663         va_list args;
 664         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 665
 666         es->s_last_error_ino = cpu_to_le32(ino);
 667         es->s_last_error_block = cpu_to_le64(block);
 668         __save_error_info(sb, function, line);
 669
 670         if (ext4_error_ratelimit(sb)) {
 671                 va_start(args, fmt);
 672                 vaf.fmt = fmt;
 673                 vaf.va = &args;
 674                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 675                        sb->s_id, function, line, grp);
 676                 if (ino)
 677                         printk(KERN_CONT "inode %lu: ", ino);
 678                 if (block)
 679                         printk(KERN_CONT "block %llu:",
 680                                (unsigned long long) block);
 681                 printk(KERN_CONT "%pV\n", &vaf);
 682                 va_end(args);
 683         }
 684
 685         if (test_opt(sb, ERRORS_CONT)) {
 686                 ext4_commit_super(sb, 0);
 687                 return;
 688         }
 689
 690         ext4_unlock_group(sb, grp);
 691         ext4_handle_error(sb);
 692         /*
 693          * We only get here in the ERRORS_RO case; relocking the group
 694          * may be dangerous, but nothing bad will happen since the
 695          * filesystem will have already been marked read/only and the
 696          * journal has been aborted.  We return 1 as a hint to callers
 697          * who might what to use the return value from
 698          * ext4_grp_locked_error() to distinguish between the
 699          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 700          * aggressively from the ext4 function in question, with a
 701          * more appropriate error code.
 702          */
 703         ext4_lock_group(sb, grp);
 704         return;
 705 }
 706
 707 void ext4_update_dynamic_rev(struct super_block *sb)
 708 {
 709         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 710
 711         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 712                 return;
 713
 714         ext4_warning(sb,
 715                      "updating to rev %d because of new feature flag, "
 716                      "running e2fsck is recommended",
 717                      EXT4_DYNAMIC_REV);
 718
 719         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 720         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 721         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 722         /* leave es->s_feature_*compat flags alone */
 723         /* es->s_uuid will be set by e2fsck if empty */
 724
 725         /*
 726          * The rest of the superblock fields should be zero, and if not it
 727          * means they are likely already in use, so leave them alone.  We
 728          * can leave it up to e2fsck to clean up any inconsistencies there.
 729          */
 730 }
 731
 732 /*
 733  * Open the external journal device
 734  */
 735 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 736 {
 737         struct block_device *bdev;
 738         char b[BDEVNAME_SIZE];
 739
 740         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 741         if (IS_ERR(bdev))
 742                 goto fail;
 743         return bdev;
 744
 745 fail:
 746         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 747                         __bdevname(dev, b), PTR_ERR(bdev));
 748         return NULL;
 749 }
 750
 751 /*
 752  * Release the journal device
 753  */
 754 static void ext4_blkdev_put(struct block_device *bdev)
 755 {
 756         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 757 }
 758
 759 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 760 {
 761         struct block_device *bdev;
 762         bdev = sbi->journal_bdev;
 763         if (bdev) {
 764                 ext4_blkdev_put(bdev);
 765                 sbi->journal_bdev = NULL;
 766         }
 767 }
 768
 769 static inline struct inode *orphan_list_entry(struct list_head *l)
 770 {
 771         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 772 }
 773
 774 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 775 {
 776         struct list_head *l;
 777
 778         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 779                  le32_to_cpu(sbi->s_es->s_last_orphan));
 780
 781         printk(KERN_ERR "sb_info orphan list:\n");
 782         list_for_each(l, &sbi->s_orphan) {
 783                 struct inode *inode = orphan_list_entry(l);
 784                 printk(KERN_ERR "  "
 785                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 786                        inode->i_sb->s_id, inode->i_ino, inode,
 787                        inode->i_mode, inode->i_nlink,
 788                        NEXT_ORPHAN(inode));
 789         }
 790 }
 791
 792 static void ext4_put_super(struct super_block *sb)
 793 {
 794         struct ext4_sb_info *sbi = EXT4_SB(sb);
 795         struct ext4_super_block *es = sbi->s_es;
 796         int i, err;
 797
 798         ext4_unregister_li_request(sb);
 799         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 800
 801         flush_workqueue(sbi->rsv_conversion_wq);
 802         destroy_workqueue(sbi->rsv_conversion_wq);
 803
 804         if (sbi->s_journal) {
 805                 err = jbd2_journal_destroy(sbi->s_journal);
 806                 sbi->s_journal = NULL;
 807                 if (err < 0)
 808                         ext4_abort(sb, "Couldn't clean up the journal");
 809         }
 810
 811         ext4_unregister_sysfs(sb);
 812         ext4_es_unregister_shrinker(sbi);
 813         del_timer_sync(&sbi->s_err_report);
 814         ext4_release_system_zone(sb);
 815         ext4_mb_release(sb);
 816         ext4_ext_release(sb);
 817         ext4_xattr_put_super(sb);
 818
 819         if (!(sb->s_flags & MS_RDONLY)) {
 820                 ext4_clear_feature_journal_needs_recovery(sb);
 821                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 822         }
 823         if (!(sb->s_flags & MS_RDONLY))
 824                 ext4_commit_super(sb, 1);
 825
 826         for (i = 0; i < sbi->s_gdb_count; i++)
 827                 brelse(sbi->s_group_desc[i]);
 828         kvfree(sbi->s_group_desc);
 829         kvfree(sbi->s_flex_groups);
 830         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 831         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 832         percpu_counter_destroy(&sbi->s_dirs_counter);
 833         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 834         brelse(sbi->s_sbh);
 835 #ifdef CONFIG_QUOTA
 836         for (i = 0; i < EXT4_MAXQUOTAS; i++)
 837                 kfree(sbi->s_qf_names[i]);
 838 #endif
 839
 840         /* Debugging code just in case the in-memory inode orphan list
 841          * isn't empty.  The on-disk one can be non-empty if we've
 842          * detected an error and taken the fs readonly, but the
 843          * in-memory list had better be clean by this point. */
 844         if (!list_empty(&sbi->s_orphan))
 845                 dump_orphan_list(sb, sbi);
 846         J_ASSERT(list_empty(&sbi->s_orphan));
 847
 848         sync_blockdev(sb->s_bdev);
 849         invalidate_bdev(sb->s_bdev);
 850         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 851                 /*
 852                  * Invalidate the journal device's buffers.  We don't want them
 853                  * floating about in memory - the physical journal device may
 854                  * hotswapped, and it breaks the `ro-after' testing code.
 855                  */
 856                 sync_blockdev(sbi->journal_bdev);
 857                 invalidate_bdev(sbi->journal_bdev);
 858                 ext4_blkdev_remove(sbi);
 859         }
 860         if (sbi->s_mb_cache) {
 861                 ext4_xattr_destroy_cache(sbi->s_mb_cache);
 862                 sbi->s_mb_cache = NULL;
 863         }
 864         if (sbi->s_mmp_tsk)
 865                 kthread_stop(sbi->s_mmp_tsk);
 866         sb->s_fs_info = NULL;
 867         /*
 868          * Now that we are completely done shutting down the
 869          * superblock, we need to actually destroy the kobject.
 870          */
 871         kobject_put(&sbi->s_kobj);
 872         wait_for_completion(&sbi->s_kobj_unregister);
 873         if (sbi->s_chksum_driver)
 874                 crypto_free_shash(sbi->s_chksum_driver);
 875         kfree(sbi->s_blockgroup_lock);
 876         kfree(sbi);
 877 }
 878
 879 static struct kmem_cache *ext4_inode_cachep;
 880
 881 /*
 882  * Called inside transaction, so use GFP_NOFS
 883  */
 884 static struct inode *ext4_alloc_inode(struct super_block *sb)
 885 {
 886         struct ext4_inode_info *ei;
 887
 888         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 889         if (!ei)
 890                 return NULL;
 891
 892         ei->vfs_inode.i_version = 1;
 893         spin_lock_init(&ei->i_raw_lock);
 894         INIT_LIST_HEAD(&ei->i_prealloc_list);
 895         spin_lock_init(&ei->i_prealloc_lock);
 896         ext4_es_init_tree(&ei->i_es_tree);
 897         rwlock_init(&ei->i_es_lock);
 898         INIT_LIST_HEAD(&ei->i_es_list);
 899         ei->i_es_all_nr = 0;
 900         ei->i_es_shk_nr = 0;
 901         ei->i_es_shrink_lblk = 0;
 902         ei->i_reserved_data_blocks = 0;
 903         ei->i_reserved_meta_blocks = 0;
 904         ei->i_allocated_meta_blocks = 0;
 905         ei->i_da_metadata_calc_len = 0;
 906         ei->i_da_metadata_calc_last_lblock = 0;
 907         spin_lock_init(&(ei->i_block_reservation_lock));
 908 #ifdef CONFIG_QUOTA
 909         ei->i_reserved_quota = 0;
 910         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
 911 #endif
 912         ei->jinode = NULL;
 913         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
 914         spin_lock_init(&ei->i_completed_io_lock);
 915         ei->i_sync_tid = 0;
 916         ei->i_datasync_tid = 0;
 917         atomic_set(&ei->i_ioend_count, 0);
 918         atomic_set(&ei->i_unwritten, 0);
 919         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
 920 #ifdef CONFIG_EXT4_FS_ENCRYPTION
 921         ei->i_crypt_info = NULL;
 922 #endif
 923         return &ei->vfs_inode;
 924 }
 925
 926 static int ext4_drop_inode(struct inode *inode)
 927 {
 928         int drop = generic_drop_inode(inode);
 929
 930         trace_ext4_drop_inode(inode, drop);
 931         return drop;
 932 }
 933
 934 static void ext4_i_callback(struct rcu_head *head)
 935 {
 936         struct inode *inode = container_of(head, struct inode, i_rcu);
 937         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 938 }
 939
 940 static void ext4_destroy_inode(struct inode *inode)
 941 {
 942         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 943                 ext4_msg(inode->i_sb, KERN_ERR,
 944                          "Inode %lu (%p): orphan list check failed!",
 945                          inode->i_ino, EXT4_I(inode));
 946                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 947                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 948                                 true);
 949                 dump_stack();
 950         }
 951         call_rcu(&inode->i_rcu, ext4_i_callback);
 952 }
 953
 954 static void init_once(void *foo)
 955 {
 956         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 957
 958         INIT_LIST_HEAD(&ei->i_orphan);
 959         init_rwsem(&ei->xattr_sem);
 960         init_rwsem(&ei->i_data_sem);
 961         inode_init_once(&ei->vfs_inode);
 962 }
 963
 964 static int __init init_inodecache(void)
 965 {
 966         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 967                                              sizeof(struct ext4_inode_info),
 968                                              0, (SLAB_RECLAIM_ACCOUNT|
 969                                                 SLAB_MEM_SPREAD),
 970                                              init_once);
 971         if (ext4_inode_cachep == NULL)
 972                 return -ENOMEM;
 973         return 0;
 974 }
 975
 976 static void destroy_inodecache(void)
 977 {
 978         /*
 979          * Make sure all delayed rcu free inodes are flushed before we
 980          * destroy cache.
 981          */
 982         rcu_barrier();
 983         kmem_cache_destroy(ext4_inode_cachep);
 984 }
 985
 986 void ext4_clear_inode(struct inode *inode)
 987 {
 988         invalidate_inode_buffers(inode);
 989         clear_inode(inode);
 990         dquot_drop(inode);
 991         ext4_discard_preallocations(inode);
 992         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
 993         if (EXT4_I(inode)->jinode) {
 994                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
 995                                                EXT4_I(inode)->jinode);
 996                 jbd2_free_inode(EXT4_I(inode)->jinode);
 997                 EXT4_I(inode)->jinode = NULL;
 998         }
 999 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1000         if (EXT4_I(inode)->i_crypt_info)
1001                 ext4_free_encryption_info(inode, EXT4_I(inode)->i_crypt_info);
1002 #endif
1003 }
1004
1005 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1006                                         u64 ino, u32 generation)
1007 {
1008         struct inode *inode;
1009
1010         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1011                 return ERR_PTR(-ESTALE);
1012         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1013                 return ERR_PTR(-ESTALE);
1014
1015         /* iget isn't really right if the inode is currently unallocated!!
1016          *
1017          * ext4_read_inode will return a bad_inode if the inode had been
1018          * deleted, so we should be safe.
1019          *
1020          * Currently we don't know the generation for parent directory, so
1021          * a generation of 0 means "accept any"
1022          */
1023         inode = ext4_iget_normal(sb, ino);
1024         if (IS_ERR(inode))
1025                 return ERR_CAST(inode);
1026         if (generation && inode->i_generation != generation) {
1027                 iput(inode);
1028                 return ERR_PTR(-ESTALE);
1029         }
1030
1031         return inode;
1032 }
1033
1034 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1035                                         int fh_len, int fh_type)
1036 {
1037         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1038                                     ext4_nfs_get_inode);
1039 }
1040
1041 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1042                                         int fh_len, int fh_type)
1043 {
1044         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1045                                     ext4_nfs_get_inode);
1046 }
1047
1048 /*
1049  * Try to release metadata pages (indirect blocks, directories) which are
1050  * mapped via the block device.  Since these pages could have journal heads
1051  * which would prevent try_to_free_buffers() from freeing them, we must use
1052  * jbd2 layer's try_to_free_buffers() function to release them.
1053  */
1054 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1055                                  gfp_t wait)
1056 {
1057         journal_t *journal = EXT4_SB(sb)->s_journal;
1058
1059         WARN_ON(PageChecked(page));
1060         if (!page_has_buffers(page))
1061                 return 0;
1062         if (journal)
1063                 return jbd2_journal_try_to_free_buffers(journal, page,
1064                                                         wait & ~__GFP_WAIT);
1065         return try_to_free_buffers(page);
1066 }
1067
1068 #ifdef CONFIG_QUOTA
1069 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1070 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1071
1072 static int ext4_write_dquot(struct dquot *dquot);
1073 static int ext4_acquire_dquot(struct dquot *dquot);
1074 static int ext4_release_dquot(struct dquot *dquot);
1075 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1076 static int ext4_write_info(struct super_block *sb, int type);
1077 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1078                          struct path *path);
1079 static int ext4_quota_off(struct super_block *sb, int type);
1080 static int ext4_quota_on_mount(struct super_block *sb, int type);
1081 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1082                                size_t len, loff_t off);
1083 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1084                                 const char *data, size_t len, loff_t off);
1085 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1086                              unsigned int flags);
1087 static int ext4_enable_quotas(struct super_block *sb);
1088
1089 static struct dquot **ext4_get_dquots(struct inode *inode)
1090 {
1091         return EXT4_I(inode)->i_dquot;
1092 }
1093
1094 static const struct dquot_operations ext4_quota_operations = {
1095         .get_reserved_space = ext4_get_reserved_space,
1096         .write_dquot    = ext4_write_dquot,
1097         .acquire_dquot  = ext4_acquire_dquot,
1098         .release_dquot  = ext4_release_dquot,
1099         .mark_dirty     = ext4_mark_dquot_dirty,
1100         .write_info     = ext4_write_info,
1101         .alloc_dquot    = dquot_alloc,
1102         .destroy_dquot  = dquot_destroy,
1103 };
1104
1105 static const struct quotactl_ops ext4_qctl_operations = {
1106         .quota_on       = ext4_quota_on,
1107         .quota_off      = ext4_quota_off,
1108         .quota_sync     = dquot_quota_sync,
1109         .get_state      = dquot_get_state,
1110         .set_info       = dquot_set_dqinfo,
1111         .get_dqblk      = dquot_get_dqblk,
1112         .set_dqblk      = dquot_set_dqblk
1113 };
1114 #endif
1115
1116 static const struct super_operations ext4_sops = {
1117         .alloc_inode    = ext4_alloc_inode,
1118         .destroy_inode  = ext4_destroy_inode,
1119         .write_inode    = ext4_write_inode,
1120         .dirty_inode    = ext4_dirty_inode,
1121         .drop_inode     = ext4_drop_inode,
1122         .evict_inode    = ext4_evict_inode,
1123         .put_super      = ext4_put_super,
1124         .sync_fs        = ext4_sync_fs,
1125         .freeze_fs      = ext4_freeze,
1126         .unfreeze_fs    = ext4_unfreeze,
1127         .statfs         = ext4_statfs,
1128         .remount_fs     = ext4_remount,
1129         .show_options   = ext4_show_options,
1130 #ifdef CONFIG_QUOTA
1131         .quota_read     = ext4_quota_read,
1132         .quota_write    = ext4_quota_write,
1133         .get_dquots     = ext4_get_dquots,
1134 #endif
1135         .bdev_try_to_free_page = bdev_try_to_free_page,
1136 };
1137
1138 static const struct export_operations ext4_export_ops = {
1139         .fh_to_dentry = ext4_fh_to_dentry,
1140         .fh_to_parent = ext4_fh_to_parent,
1141         .get_parent = ext4_get_parent,
1142 };
1143
1144 enum {
1145         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1146         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1147         Opt_nouid32, Opt_debug, Opt_removed,
1148         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1149         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1150         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1151         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1152         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1153         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1154         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1155         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1156         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1157         Opt_usrquota, Opt_grpquota, Opt_i_version, Opt_dax,
1158         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1159         Opt_lazytime, Opt_nolazytime,
1160         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1161         Opt_inode_readahead_blks, Opt_journal_ioprio,
1162         Opt_dioread_nolock, Opt_dioread_lock,
1163         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1164         Opt_max_dir_size_kb, Opt_nojournal_checksum,
1165 };
1166
1167 static const match_table_t tokens = {
1168         {Opt_bsd_df, "bsddf"},
1169         {Opt_minix_df, "minixdf"},
1170         {Opt_grpid, "grpid"},
1171         {Opt_grpid, "bsdgroups"},
1172         {Opt_nogrpid, "nogrpid"},
1173         {Opt_nogrpid, "sysvgroups"},
1174         {Opt_resgid, "resgid=%u"},
1175         {Opt_resuid, "resuid=%u"},
1176         {Opt_sb, "sb=%u"},
1177         {Opt_err_cont, "errors=continue"},
1178         {Opt_err_panic, "errors=panic"},
1179         {Opt_err_ro, "errors=remount-ro"},
1180         {Opt_nouid32, "nouid32"},
1181         {Opt_debug, "debug"},
1182         {Opt_removed, "oldalloc"},
1183         {Opt_removed, "orlov"},
1184         {Opt_user_xattr, "user_xattr"},
1185         {Opt_nouser_xattr, "nouser_xattr"},
1186         {Opt_acl, "acl"},
1187         {Opt_noacl, "noacl"},
1188         {Opt_noload, "norecovery"},
1189         {Opt_noload, "noload"},
1190         {Opt_removed, "nobh"},
1191         {Opt_removed, "bh"},
1192         {Opt_commit, "commit=%u"},
1193         {Opt_min_batch_time, "min_batch_time=%u"},
1194         {Opt_max_batch_time, "max_batch_time=%u"},
1195         {Opt_journal_dev, "journal_dev=%u"},
1196         {Opt_journal_path, "journal_path=%s"},
1197         {Opt_journal_checksum, "journal_checksum"},
1198         {Opt_nojournal_checksum, "nojournal_checksum"},
1199         {Opt_journal_async_commit, "journal_async_commit"},
1200         {Opt_abort, "abort"},
1201         {Opt_data_journal, "data=journal"},
1202         {Opt_data_ordered, "data=ordered"},
1203         {Opt_data_writeback, "data=writeback"},
1204         {Opt_data_err_abort, "data_err=abort"},
1205         {Opt_data_err_ignore, "data_err=ignore"},
1206         {Opt_offusrjquota, "usrjquota="},
1207         {Opt_usrjquota, "usrjquota=%s"},
1208         {Opt_offgrpjquota, "grpjquota="},
1209         {Opt_grpjquota, "grpjquota=%s"},
1210         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1211         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1212         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1213         {Opt_grpquota, "grpquota"},
1214         {Opt_noquota, "noquota"},
1215         {Opt_quota, "quota"},
1216         {Opt_usrquota, "usrquota"},
1217         {Opt_barrier, "barrier=%u"},
1218         {Opt_barrier, "barrier"},
1219         {Opt_nobarrier, "nobarrier"},
1220         {Opt_i_version, "i_version"},
1221         {Opt_dax, "dax"},
1222         {Opt_stripe, "stripe=%u"},
1223         {Opt_delalloc, "delalloc"},
1224         {Opt_lazytime, "lazytime"},
1225         {Opt_nolazytime, "nolazytime"},
1226         {Opt_nodelalloc, "nodelalloc"},
1227         {Opt_removed, "mblk_io_submit"},
1228         {Opt_removed, "nomblk_io_submit"},
1229         {Opt_block_validity, "block_validity"},
1230         {Opt_noblock_validity, "noblock_validity"},
1231         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1232         {Opt_journal_ioprio, "journal_ioprio=%u"},
1233         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1234         {Opt_auto_da_alloc, "auto_da_alloc"},
1235         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1236         {Opt_dioread_nolock, "dioread_nolock"},
1237         {Opt_dioread_lock, "dioread_lock"},
1238         {Opt_discard, "discard"},
1239         {Opt_nodiscard, "nodiscard"},
1240         {Opt_init_itable, "init_itable=%u"},
1241         {Opt_init_itable, "init_itable"},
1242         {Opt_noinit_itable, "noinit_itable"},
1243         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1244         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1245         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1246         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1247         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1248         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1249         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1250         {Opt_err, NULL},
1251 };
1252
1253 static ext4_fsblk_t get_sb_block(void **data)
1254 {
1255         ext4_fsblk_t    sb_block;
1256         char            *options = (char *) *data;
1257
1258         if (!options || strncmp(options, "sb=", 3) != 0)
1259                 return 1;       /* Default location */
1260
1261         options += 3;
1262         /* TODO: use simple_strtoll with >32bit ext4 */
1263         sb_block = simple_strtoul(options, &options, 0);
1264         if (*options && *options != ',') {
1265                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1266                        (char *) *data);
1267                 return 1;
1268         }
1269         if (*options == ',')
1270                 options++;
1271         *data = (void *) options;
1272
1273         return sb_block;
1274 }
1275
1276 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1277 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1278         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1279
1280 #ifdef CONFIG_QUOTA
1281 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1282 {
1283         struct ext4_sb_info *sbi = EXT4_SB(sb);
1284         char *qname;
1285         int ret = -1;
1286
1287         if (sb_any_quota_loaded(sb) &&
1288                 !sbi->s_qf_names[qtype]) {
1289                 ext4_msg(sb, KERN_ERR,
1290                         "Cannot change journaled "
1291                         "quota options when quota turned on");
1292                 return -1;
1293         }
1294         if (ext4_has_feature_quota(sb)) {
1295                 ext4_msg(sb, KERN_ERR, "Cannot set journaled quota options "
1296                          "when QUOTA feature is enabled");
1297                 return -1;
1298         }
1299         qname = match_strdup(args);
1300         if (!qname) {
1301                 ext4_msg(sb, KERN_ERR,
1302                         "Not enough memory for storing quotafile name");
1303                 return -1;
1304         }
1305         if (sbi->s_qf_names[qtype]) {
1306                 if (strcmp(sbi->s_qf_names[qtype], qname) == 0)
1307                         ret = 1;
1308                 else
1309                         ext4_msg(sb, KERN_ERR,
1310                                  "%s quota file already specified",
1311                                  QTYPE2NAME(qtype));
1312                 goto errout;
1313         }
1314         if (strchr(qname, '/')) {
1315                 ext4_msg(sb, KERN_ERR,
1316                         "quotafile must be on filesystem root");
1317                 goto errout;
1318         }
1319         sbi->s_qf_names[qtype] = qname;
1320         set_opt(sb, QUOTA);
1321         return 1;
1322 errout:
1323         kfree(qname);
1324         return ret;
1325 }
1326
1327 static int clear_qf_name(struct super_block *sb, int qtype)
1328 {
1329
1330         struct ext4_sb_info *sbi = EXT4_SB(sb);
1331
1332         if (sb_any_quota_loaded(sb) &&
1333                 sbi->s_qf_names[qtype]) {
1334                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1335                         " when quota turned on");
1336                 return -1;
1337         }
1338         kfree(sbi->s_qf_names[qtype]);
1339         sbi->s_qf_names[qtype] = NULL;
1340         return 1;
1341 }
1342 #endif
1343
1344 #define MOPT_SET        0x0001
1345 #define MOPT_CLEAR      0x0002
1346 #define MOPT_NOSUPPORT  0x0004
1347 #define MOPT_EXPLICIT   0x0008
1348 #define MOPT_CLEAR_ERR  0x0010
1349 #define MOPT_GTE0       0x0020
1350 #ifdef CONFIG_QUOTA
1351 #define MOPT_Q          0
1352 #define MOPT_QFMT       0x0040
1353 #else
1354 #define MOPT_Q          MOPT_NOSUPPORT
1355 #define MOPT_QFMT       MOPT_NOSUPPORT
1356 #endif
1357 #define MOPT_DATAJ      0x0080
1358 #define MOPT_NO_EXT2    0x0100
1359 #define MOPT_NO_EXT3    0x0200
1360 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1361 #define MOPT_STRING     0x0400
1362
1363 static const struct mount_opts {
1364         int     token;
1365         int     mount_opt;
1366         int     flags;
1367 } ext4_mount_opts[] = {
1368         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1369         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1370         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1371         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1372         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1373         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1374         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1375          MOPT_EXT4_ONLY | MOPT_SET},
1376         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1377          MOPT_EXT4_ONLY | MOPT_CLEAR},
1378         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1379         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1380         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1381          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1382         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1383          MOPT_EXT4_ONLY | MOPT_CLEAR},
1384         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1385          MOPT_EXT4_ONLY | MOPT_CLEAR},
1386         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1387          MOPT_EXT4_ONLY | MOPT_SET},
1388         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1389                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1390          MOPT_EXT4_ONLY | MOPT_SET},
1391         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1392         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1393         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1394         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1395         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1396          MOPT_NO_EXT2 | MOPT_SET},
1397         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1398          MOPT_NO_EXT2 | MOPT_CLEAR},
1399         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1400         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1401         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1402         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1403         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1404         {Opt_commit, 0, MOPT_GTE0},
1405         {Opt_max_batch_time, 0, MOPT_GTE0},
1406         {Opt_min_batch_time, 0, MOPT_GTE0},
1407         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1408         {Opt_init_itable, 0, MOPT_GTE0},
1409         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1410         {Opt_stripe, 0, MOPT_GTE0},
1411         {Opt_resuid, 0, MOPT_GTE0},
1412         {Opt_resgid, 0, MOPT_GTE0},
1413         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1414         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1415         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1416         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1417         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1418         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1419          MOPT_NO_EXT2 | MOPT_DATAJ},
1420         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1421         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1422 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1423         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1424         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1425 #else
1426         {Opt_acl, 0, MOPT_NOSUPPORT},
1427         {Opt_noacl, 0, MOPT_NOSUPPORT},
1428 #endif
1429         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1430         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1431         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1432         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1433                                                         MOPT_SET | MOPT_Q},
1434         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1435                                                         MOPT_SET | MOPT_Q},
1436         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1437                        EXT4_MOUNT_GRPQUOTA), MOPT_CLEAR | MOPT_Q},
1438         {Opt_usrjquota, 0, MOPT_Q},
1439         {Opt_grpjquota, 0, MOPT_Q},
1440         {Opt_offusrjquota, 0, MOPT_Q},
1441         {Opt_offgrpjquota, 0, MOPT_Q},
1442         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1443         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1444         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1445         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1446         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1447         {Opt_err, 0, 0}
1448 };
1449
1450 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1451                             substring_t *args, unsigned long *journal_devnum,
1452                             unsigned int *journal_ioprio, int is_remount)
1453 {
1454         struct ext4_sb_info *sbi = EXT4_SB(sb);
1455         const struct mount_opts *m;
1456         kuid_t uid;
1457         kgid_t gid;
1458         int arg = 0;
1459
1460 #ifdef CONFIG_QUOTA
1461         if (token == Opt_usrjquota)
1462                 return set_qf_name(sb, USRQUOTA, &args[0]);
1463         else if (token == Opt_grpjquota)
1464                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1465         else if (token == Opt_offusrjquota)
1466                 return clear_qf_name(sb, USRQUOTA);
1467         else if (token == Opt_offgrpjquota)
1468                 return clear_qf_name(sb, GRPQUOTA);
1469 #endif
1470         switch (token) {
1471         case Opt_noacl:
1472         case Opt_nouser_xattr:
1473                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1474                 break;
1475         case Opt_sb:
1476                 return 1;       /* handled by get_sb_block() */
1477         case Opt_removed:
1478                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1479                 return 1;
1480         case Opt_abort:
1481                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1482                 return 1;
1483         case Opt_i_version:
1484                 sb->s_flags |= MS_I_VERSION;
1485                 return 1;
1486         case Opt_lazytime:
1487                 sb->s_flags |= MS_LAZYTIME;
1488                 return 1;
1489         case Opt_nolazytime:
1490                 sb->s_flags &= ~MS_LAZYTIME;
1491                 return 1;
1492         }
1493
1494         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1495                 if (token == m->token)
1496                         break;
1497
1498         if (m->token == Opt_err) {
1499                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1500                          "or missing value", opt);
1501                 return -1;
1502         }
1503
1504         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1505                 ext4_msg(sb, KERN_ERR,
1506                          "Mount option \"%s\" incompatible with ext2", opt);
1507                 return -1;
1508         }
1509         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1510                 ext4_msg(sb, KERN_ERR,
1511                          "Mount option \"%s\" incompatible with ext3", opt);
1512                 return -1;
1513         }
1514
1515         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1516                 return -1;
1517         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1518                 return -1;
1519         if (m->flags & MOPT_EXPLICIT) {
1520                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1521                         set_opt2(sb, EXPLICIT_DELALLOC);
1522                 } else
1523                         return -1;
1524         }
1525         if (m->flags & MOPT_CLEAR_ERR)
1526                 clear_opt(sb, ERRORS_MASK);
1527         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1528                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1529                          "options when quota turned on");
1530                 return -1;
1531         }
1532
1533         if (m->flags & MOPT_NOSUPPORT) {
1534                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1535         } else if (token == Opt_commit) {
1536                 if (arg == 0)
1537                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1538                 sbi->s_commit_interval = HZ * arg;
1539         } else if (token == Opt_max_batch_time) {
1540                 sbi->s_max_batch_time = arg;
1541         } else if (token == Opt_min_batch_time) {
1542                 sbi->s_min_batch_time = arg;
1543         } else if (token == Opt_inode_readahead_blks) {
1544                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1545                         ext4_msg(sb, KERN_ERR,
1546                                  "EXT4-fs: inode_readahead_blks must be "
1547                                  "0 or a power of 2 smaller than 2^31");
1548                         return -1;
1549                 }
1550                 sbi->s_inode_readahead_blks = arg;
1551         } else if (token == Opt_init_itable) {
1552                 set_opt(sb, INIT_INODE_TABLE);
1553                 if (!args->from)
1554                         arg = EXT4_DEF_LI_WAIT_MULT;
1555                 sbi->s_li_wait_mult = arg;
1556         } else if (token == Opt_max_dir_size_kb) {
1557                 sbi->s_max_dir_size_kb = arg;
1558         } else if (token == Opt_stripe) {
1559                 sbi->s_stripe = arg;
1560         } else if (token == Opt_resuid) {
1561                 uid = make_kuid(current_user_ns(), arg);
1562                 if (!uid_valid(uid)) {
1563                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1564                         return -1;
1565                 }
1566                 sbi->s_resuid = uid;
1567         } else if (token == Opt_resgid) {
1568                 gid = make_kgid(current_user_ns(), arg);
1569                 if (!gid_valid(gid)) {
1570                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1571                         return -1;
1572                 }
1573                 sbi->s_resgid = gid;
1574         } else if (token == Opt_journal_dev) {
1575                 if (is_remount) {
1576                         ext4_msg(sb, KERN_ERR,
1577                                  "Cannot specify journal on remount");
1578                         return -1;
1579                 }
1580                 *journal_devnum = arg;
1581         } else if (token == Opt_journal_path) {
1582                 char *journal_path;
1583                 struct inode *journal_inode;
1584                 struct path path;
1585                 int error;
1586
1587                 if (is_remount) {
1588                         ext4_msg(sb, KERN_ERR,
1589                                  "Cannot specify journal on remount");
1590                         return -1;
1591                 }
1592                 journal_path = match_strdup(&args[0]);
1593                 if (!journal_path) {
1594                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1595                                 "journal device string");
1596                         return -1;
1597                 }
1598
1599                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1600                 if (error) {
1601                         ext4_msg(sb, KERN_ERR, "error: could not find "
1602                                 "journal device path: error %d", error);
1603                         kfree(journal_path);
1604                         return -1;
1605                 }
1606
1607                 journal_inode = d_inode(path.dentry);
1608                 if (!S_ISBLK(journal_inode->i_mode)) {
1609                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1610                                 "is not a block device", journal_path);
1611                         path_put(&path);
1612                         kfree(journal_path);
1613                         return -1;
1614                 }
1615
1616                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1617                 path_put(&path);
1618                 kfree(journal_path);
1619         } else if (token == Opt_journal_ioprio) {
1620                 if (arg > 7) {
1621                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1622                                  " (must be 0-7)");
1623                         return -1;
1624                 }
1625                 *journal_ioprio =
1626                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1627         } else if (token == Opt_test_dummy_encryption) {
1628 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1629                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1630                 ext4_msg(sb, KERN_WARNING,
1631                          "Test dummy encryption mode enabled");
1632 #else
1633                 ext4_msg(sb, KERN_WARNING,
1634                          "Test dummy encryption mount option ignored");
1635 #endif
1636         } else if (m->flags & MOPT_DATAJ) {
1637                 if (is_remount) {
1638                         if (!sbi->s_journal)
1639                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1640                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1641                                 ext4_msg(sb, KERN_ERR,
1642                                          "Cannot change data mode on remount");
1643                                 return -1;
1644                         }
1645                 } else {
1646                         clear_opt(sb, DATA_FLAGS);
1647                         sbi->s_mount_opt |= m->mount_opt;
1648                 }
1649 #ifdef CONFIG_QUOTA
1650         } else if (m->flags & MOPT_QFMT) {
1651                 if (sb_any_quota_loaded(sb) &&
1652                     sbi->s_jquota_fmt != m->mount_opt) {
1653                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1654                                  "quota options when quota turned on");
1655                         return -1;
1656                 }
1657                 if (ext4_has_feature_quota(sb)) {
1658                         ext4_msg(sb, KERN_ERR,
1659                                  "Cannot set journaled quota options "
1660                                  "when QUOTA feature is enabled");
1661                         return -1;
1662                 }
1663                 sbi->s_jquota_fmt = m->mount_opt;
1664 #endif
1665 #ifndef CONFIG_FS_DAX
1666         } else if (token == Opt_dax) {
1667                 ext4_msg(sb, KERN_INFO, "dax option not supported");
1668                 return -1;
1669 #endif
1670         } else {
1671                 if (!args->from)
1672                         arg = 1;
1673                 if (m->flags & MOPT_CLEAR)
1674                         arg = !arg;
1675                 else if (unlikely(!(m->flags & MOPT_SET))) {
1676                         ext4_msg(sb, KERN_WARNING,
1677                                  "buggy handling of option %s", opt);
1678                         WARN_ON(1);
1679                         return -1;
1680                 }
1681                 if (arg != 0)
1682                         sbi->s_mount_opt |= m->mount_opt;
1683                 else
1684                         sbi->s_mount_opt &= ~m->mount_opt;
1685         }
1686         return 1;
1687 }
1688
1689 static int parse_options(char *options, struct super_block *sb,
1690                          unsigned long *journal_devnum,
1691                          unsigned int *journal_ioprio,
1692                          int is_remount)
1693 {
1694         struct ext4_sb_info *sbi = EXT4_SB(sb);
1695         char *p;
1696         substring_t args[MAX_OPT_ARGS];
1697         int token;
1698
1699         if (!options)
1700                 return 1;
1701
1702         while ((p = strsep(&options, ",")) != NULL) {
1703                 if (!*p)
1704                         continue;
1705                 /*
1706                  * Initialize args struct so we know whether arg was
1707                  * found; some options take optional arguments.
1708                  */
1709                 args[0].to = args[0].from = NULL;
1710                 token = match_token(p, tokens, args);
1711                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1712                                      journal_ioprio, is_remount) < 0)
1713                         return 0;
1714         }
1715 #ifdef CONFIG_QUOTA
1716         if (ext4_has_feature_quota(sb) &&
1717             (test_opt(sb, USRQUOTA) || test_opt(sb, GRPQUOTA))) {
1718                 ext4_msg(sb, KERN_ERR, "Cannot set quota options when QUOTA "
1719                          "feature is enabled");
1720                 return 0;
1721         }
1722         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1723                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1724                         clear_opt(sb, USRQUOTA);
1725
1726                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1727                         clear_opt(sb, GRPQUOTA);
1728
1729                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1730                         ext4_msg(sb, KERN_ERR, "old and new quota "
1731                                         "format mixing");
1732                         return 0;
1733                 }
1734
1735                 if (!sbi->s_jquota_fmt) {
1736                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1737                                         "not specified");
1738                         return 0;
1739                 }
1740         }
1741 #endif
1742         if (test_opt(sb, DIOREAD_NOLOCK)) {
1743                 int blocksize =
1744                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
1745
1746                 if (blocksize < PAGE_CACHE_SIZE) {
1747                         ext4_msg(sb, KERN_ERR, "can't mount with "
1748                                  "dioread_nolock if block size != PAGE_SIZE");
1749                         return 0;
1750                 }
1751         }
1752         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
1753             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
1754                 ext4_msg(sb, KERN_ERR, "can't mount with journal_async_commit "
1755                          "in data=ordered mode");
1756                 return 0;
1757         }
1758         return 1;
1759 }
1760
1761 static inline void ext4_show_quota_options(struct seq_file *seq,
1762                                            struct super_block *sb)
1763 {
1764 #if defined(CONFIG_QUOTA)
1765         struct ext4_sb_info *sbi = EXT4_SB(sb);
1766
1767         if (sbi->s_jquota_fmt) {
1768                 char *fmtname = "";
1769
1770                 switch (sbi->s_jquota_fmt) {
1771                 case QFMT_VFS_OLD:
1772                         fmtname = "vfsold";
1773                         break;
1774                 case QFMT_VFS_V0:
1775                         fmtname = "vfsv0";
1776                         break;
1777                 case QFMT_VFS_V1:
1778                         fmtname = "vfsv1";
1779                         break;
1780                 }
1781                 seq_printf(seq, ",jqfmt=%s", fmtname);
1782         }
1783
1784         if (sbi->s_qf_names[USRQUOTA])
1785                 seq_show_option(seq, "usrjquota", sbi->s_qf_names[USRQUOTA]);
1786
1787         if (sbi->s_qf_names[GRPQUOTA])
1788                 seq_show_option(seq, "grpjquota", sbi->s_qf_names[GRPQUOTA]);
1789 #endif
1790 }
1791
1792 static const char *token2str(int token)
1793 {
1794         const struct match_token *t;
1795
1796         for (t = tokens; t->token != Opt_err; t++)
1797                 if (t->token == token && !strchr(t->pattern, '='))
1798                         break;
1799         return t->pattern;
1800 }
1801
1802 /*
1803  * Show an option if
1804  *  - it's set to a non-default value OR
1805  *  - if the per-sb default is different from the global default
1806  */
1807 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1808                               int nodefs)
1809 {
1810         struct ext4_sb_info *sbi = EXT4_SB(sb);
1811         struct ext4_super_block *es = sbi->s_es;
1812         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1813         const struct mount_opts *m;
1814         char sep = nodefs ? '\n' : ',';
1815
1816 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1817 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1818
1819         if (sbi->s_sb_block != 1)
1820                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1821
1822         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1823                 int want_set = m->flags & MOPT_SET;
1824                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1825                     (m->flags & MOPT_CLEAR_ERR))
1826                         continue;
1827                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1828                         continue; /* skip if same as the default */
1829                 if ((want_set &&
1830                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1831                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1832                         continue; /* select Opt_noFoo vs Opt_Foo */
1833                 SEQ_OPTS_PRINT("%s", token2str(m->token));
1834         }
1835
1836         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
1837             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1838                 SEQ_OPTS_PRINT("resuid=%u",
1839                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
1840         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
1841             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1842                 SEQ_OPTS_PRINT("resgid=%u",
1843                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
1844         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1845         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1846                 SEQ_OPTS_PUTS("errors=remount-ro");
1847         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1848                 SEQ_OPTS_PUTS("errors=continue");
1849         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1850                 SEQ_OPTS_PUTS("errors=panic");
1851         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
1852                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
1853         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
1854                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
1855         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
1856                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
1857         if (sb->s_flags & MS_I_VERSION)
1858                 SEQ_OPTS_PUTS("i_version");
1859         if (nodefs || sbi->s_stripe)
1860                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
1861         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
1862                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1863                         SEQ_OPTS_PUTS("data=journal");
1864                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1865                         SEQ_OPTS_PUTS("data=ordered");
1866                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1867                         SEQ_OPTS_PUTS("data=writeback");
1868         }
1869         if (nodefs ||
1870             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1871                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
1872                                sbi->s_inode_readahead_blks);
1873
1874         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
1875                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
1876                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
1877         if (nodefs || sbi->s_max_dir_size_kb)
1878                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
1879
1880         ext4_show_quota_options(seq, sb);
1881         return 0;
1882 }
1883
1884 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
1885 {
1886         return _ext4_show_options(seq, root->d_sb, 0);
1887 }
1888
1889 int ext4_seq_options_show(struct seq_file *seq, void *offset)
1890 {
1891         struct super_block *sb = seq->private;
1892         int rc;
1893
1894         seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
1895         rc = _ext4_show_options(seq, sb, 1);
1896         seq_puts(seq, "\n");
1897         return rc;
1898 }
1899
1900 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1901                             int read_only)
1902 {
1903         struct ext4_sb_info *sbi = EXT4_SB(sb);
1904         int res = 0;
1905
1906         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1907                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1908                          "forcing read-only mode");
1909                 res = MS_RDONLY;
1910         }
1911         if (read_only)
1912                 goto done;
1913         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1914                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1915                          "running e2fsck is recommended");
1916         else if (sbi->s_mount_state & EXT4_ERROR_FS)
1917                 ext4_msg(sb, KERN_WARNING,
1918                          "warning: mounting fs with errors, "
1919                          "running e2fsck is recommended");
1920         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1921                  le16_to_cpu(es->s_mnt_count) >=
1922                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1923                 ext4_msg(sb, KERN_WARNING,
1924                          "warning: maximal mount count reached, "
1925                          "running e2fsck is recommended");
1926         else if (le32_to_cpu(es->s_checkinterval) &&
1927                 (le32_to_cpu(es->s_lastcheck) +
1928                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1929                 ext4_msg(sb, KERN_WARNING,
1930                          "warning: checktime reached, "
1931                          "running e2fsck is recommended");
1932         if (!sbi->s_journal)
1933                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1934         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1935                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1936         le16_add_cpu(&es->s_mnt_count, 1);
1937         es->s_mtime = cpu_to_le32(get_seconds());
1938         ext4_update_dynamic_rev(sb);
1939         if (sbi->s_journal)
1940                 ext4_set_feature_journal_needs_recovery(sb);
1941
1942         ext4_commit_super(sb, 1);
1943 done:
1944         if (test_opt(sb, DEBUG))
1945                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1946                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1947                         sb->s_blocksize,
1948                         sbi->s_groups_count,
1949                         EXT4_BLOCKS_PER_GROUP(sb),
1950                         EXT4_INODES_PER_GROUP(sb),
1951                         sbi->s_mount_opt, sbi->s_mount_opt2);
1952
1953         cleancache_init_fs(sb);
1954         return res;
1955 }
1956
1957 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
1958 {
1959         struct ext4_sb_info *sbi = EXT4_SB(sb);
1960         struct flex_groups *new_groups;
1961         int size;
1962
1963         if (!sbi->s_log_groups_per_flex)
1964                 return 0;
1965
1966         size = ext4_flex_group(sbi, ngroup - 1) + 1;
1967         if (size <= sbi->s_flex_groups_allocated)
1968                 return 0;
1969
1970         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
1971         new_groups = ext4_kvzalloc(size, GFP_KERNEL);
1972         if (!new_groups) {
1973                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
1974                          size / (int) sizeof(struct flex_groups));
1975                 return -ENOMEM;
1976         }
1977
1978         if (sbi->s_flex_groups) {
1979                 memcpy(new_groups, sbi->s_flex_groups,
1980                        (sbi->s_flex_groups_allocated *
1981                         sizeof(struct flex_groups)));
1982                 kvfree(sbi->s_flex_groups);
1983         }
1984         sbi->s_flex_groups = new_groups;
1985         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
1986         return 0;
1987 }
1988
1989 static int ext4_fill_flex_info(struct super_block *sb)
1990 {
1991         struct ext4_sb_info *sbi = EXT4_SB(sb);
1992         struct ext4_group_desc *gdp = NULL;
1993         ext4_group_t flex_group;
1994         int i, err;
1995
1996         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1997         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
1998                 sbi->s_log_groups_per_flex = 0;
1999                 return 1;
2000         }
2001
2002         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2003         if (err)
2004                 goto failed;
2005
2006         for (i = 0; i < sbi->s_groups_count; i++) {
2007                 gdp = ext4_get_group_desc(sb, i, NULL);
2008
2009                 flex_group = ext4_flex_group(sbi, i);
2010                 atomic_add(ext4_free_inodes_count(sb, gdp),
2011                            &sbi->s_flex_groups[flex_group].free_inodes);
2012                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2013                              &sbi->s_flex_groups[flex_group].free_clusters);
2014                 atomic_add(ext4_used_dirs_count(sb, gdp),
2015                            &sbi->s_flex_groups[flex_group].used_dirs);
2016         }
2017
2018         return 1;
2019 failed:
2020         return 0;
2021 }
2022
2023 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2024                                    struct ext4_group_desc *gdp)
2025 {
2026         int offset;
2027         __u16 crc = 0;
2028         __le32 le_group = cpu_to_le32(block_group);
2029         struct ext4_sb_info *sbi = EXT4_SB(sb);
2030
2031         if (ext4_has_metadata_csum(sbi->s_sb)) {
2032                 /* Use new metadata_csum algorithm */
2033                 __le16 save_csum;
2034                 __u32 csum32;
2035
2036                 save_csum = gdp->bg_checksum;
2037                 gdp->bg_checksum = 0;
2038                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2039                                      sizeof(le_group));
2040                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp,
2041                                      sbi->s_desc_size);
2042                 gdp->bg_checksum = save_csum;
2043
2044                 crc = csum32 & 0xFFFF;
2045                 goto out;
2046         }
2047
2048         /* old crc16 code */
2049         if (!ext4_has_feature_gdt_csum(sb))
2050                 return 0;
2051
2052         offset = offsetof(struct ext4_group_desc, bg_checksum);
2053
2054         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2055         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2056         crc = crc16(crc, (__u8 *)gdp, offset);
2057         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2058         /* for checksum of struct ext4_group_desc do the rest...*/
2059         if (ext4_has_feature_64bit(sb) &&
2060             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2061                 crc = crc16(crc, (__u8 *)gdp + offset,
2062                             le16_to_cpu(sbi->s_es->s_desc_size) -
2063                                 offset);
2064
2065 out:
2066         return cpu_to_le16(crc);
2067 }
2068
2069 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2070                                 struct ext4_group_desc *gdp)
2071 {
2072         if (ext4_has_group_desc_csum(sb) &&
2073             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2074                 return 0;
2075
2076         return 1;
2077 }
2078
2079 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2080                               struct ext4_group_desc *gdp)
2081 {
2082         if (!ext4_has_group_desc_csum(sb))
2083                 return;
2084         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2085 }
2086
2087 /* Called at mount-time, super-block is locked */
2088 static int ext4_check_descriptors(struct super_block *sb,
2089                                   ext4_group_t *first_not_zeroed)
2090 {
2091         struct ext4_sb_info *sbi = EXT4_SB(sb);
2092         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2093         ext4_fsblk_t last_block;
2094         ext4_fsblk_t block_bitmap;
2095         ext4_fsblk_t inode_bitmap;
2096         ext4_fsblk_t inode_table;
2097         int flexbg_flag = 0;
2098         ext4_group_t i, grp = sbi->s_groups_count;
2099
2100         if (ext4_has_feature_flex_bg(sb))
2101                 flexbg_flag = 1;
2102
2103         ext4_debug("Checking group descriptors");
2104
2105         for (i = 0; i < sbi->s_groups_count; i++) {
2106                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2107
2108                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2109                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2110                 else
2111                         last_block = first_block +
2112                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2113
2114                 if ((grp == sbi->s_groups_count) &&
2115                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2116                         grp = i;
2117
2118                 block_bitmap = ext4_block_bitmap(sb, gdp);
2119                 if (block_bitmap < first_block || block_bitmap > last_block) {
2120                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2121                                "Block bitmap for group %u not in group "
2122                                "(block %llu)!", i, block_bitmap);
2123                         return 0;
2124                 }
2125                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2126                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2127                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2128                                "Inode bitmap for group %u not in group "
2129                                "(block %llu)!", i, inode_bitmap);
2130                         return 0;
2131                 }
2132                 inode_table = ext4_inode_table(sb, gdp);
2133                 if (inode_table < first_block ||
2134                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2135                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2136                                "Inode table for group %u not in group "
2137                                "(block %llu)!", i, inode_table);
2138                         return 0;
2139                 }
2140                 ext4_lock_group(sb, i);
2141                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2142                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2143                                  "Checksum for group %u failed (%u!=%u)",
2144                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2145                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2146                         if (!(sb->s_flags & MS_RDONLY)) {
2147                                 ext4_unlock_group(sb, i);
2148                                 return 0;
2149                         }
2150                 }
2151                 ext4_unlock_group(sb, i);
2152                 if (!flexbg_flag)
2153                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2154         }
2155         if (NULL != first_not_zeroed)
2156                 *first_not_zeroed = grp;
2157         return 1;
2158 }
2159
2160 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2161  * the superblock) which were deleted from all directories, but held open by
2162  * a process at the time of a crash.  We walk the list and try to delete these
2163  * inodes at recovery time (only with a read-write filesystem).
2164  *
2165  * In order to keep the orphan inode chain consistent during traversal (in
2166  * case of crash during recovery), we link each inode into the superblock
2167  * orphan list_head and handle it the same way as an inode deletion during
2168  * normal operation (which journals the operations for us).
2169  *
2170  * We only do an iget() and an iput() on each inode, which is very safe if we
2171  * accidentally point at an in-use or already deleted inode.  The worst that
2172  * can happen in this case is that we get a "bit already cleared" message from
2173  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2174  * e2fsck was run on this filesystem, and it must have already done the orphan
2175  * inode cleanup for us, so we can safely abort without any further action.
2176  */
2177 static void ext4_orphan_cleanup(struct super_block *sb,
2178                                 struct ext4_super_block *es)
2179 {
2180         unsigned int s_flags = sb->s_flags;
2181         int nr_orphans = 0, nr_truncates = 0;
2182 #ifdef CONFIG_QUOTA
2183         int i;
2184 #endif
2185         if (!es->s_last_orphan) {
2186                 jbd_debug(4, "no orphan inodes to clean up\n");
2187                 return;
2188         }
2189
2190         if (bdev_read_only(sb->s_bdev)) {
2191                 ext4_msg(sb, KERN_ERR, "write access "
2192                         "unavailable, skipping orphan cleanup");
2193                 return;
2194         }
2195
2196         /* Check if feature set would not allow a r/w mount */
2197         if (!ext4_feature_set_ok(sb, 0)) {
2198                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2199                          "unknown ROCOMPAT features");
2200                 return;
2201         }
2202
2203         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2204                 /* don't clear list on RO mount w/ errors */
2205                 if (es->s_last_orphan && !(s_flags & MS_RDONLY)) {
2206                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2207                                   "clearing orphan list.\n");
2208                         es->s_last_orphan = 0;
2209                 }
2210                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2211                 return;
2212         }
2213
2214         if (s_flags & MS_RDONLY) {
2215                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2216                 sb->s_flags &= ~MS_RDONLY;
2217         }
2218 #ifdef CONFIG_QUOTA
2219         /* Needed for iput() to work correctly and not trash data */
2220         sb->s_flags |= MS_ACTIVE;
2221         /* Turn on quotas so that they are updated correctly */
2222         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2223                 if (EXT4_SB(sb)->s_qf_names[i]) {
2224                         int ret = ext4_quota_on_mount(sb, i);
2225                         if (ret < 0)
2226                                 ext4_msg(sb, KERN_ERR,
2227                                         "Cannot turn on journaled "
2228                                         "quota: error %d", ret);
2229                 }
2230         }
2231 #endif
2232
2233         while (es->s_last_orphan) {
2234                 struct inode *inode;
2235
2236                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2237                 if (IS_ERR(inode)) {
2238                         es->s_last_orphan = 0;
2239                         break;
2240                 }
2241
2242                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2243                 dquot_initialize(inode);
2244                 if (inode->i_nlink) {
2245                         if (test_opt(sb, DEBUG))
2246                                 ext4_msg(sb, KERN_DEBUG,
2247                                         "%s: truncating inode %lu to %lld bytes",
2248                                         __func__, inode->i_ino, inode->i_size);
2249                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2250                                   inode->i_ino, inode->i_size);
2251                         mutex_lock(&inode->i_mutex);
2252                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2253                         ext4_truncate(inode);
2254                         mutex_unlock(&inode->i_mutex);
2255                         nr_truncates++;
2256                 } else {
2257                         if (test_opt(sb, DEBUG))
2258                                 ext4_msg(sb, KERN_DEBUG,
2259                                         "%s: deleting unreferenced inode %lu",
2260                                         __func__, inode->i_ino);
2261                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2262                                   inode->i_ino);
2263                         nr_orphans++;
2264                 }
2265                 iput(inode);  /* The delete magic happens here! */
2266         }
2267
2268 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2269
2270         if (nr_orphans)
2271                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2272                        PLURAL(nr_orphans));
2273         if (nr_truncates)
2274                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2275                        PLURAL(nr_truncates));
2276 #ifdef CONFIG_QUOTA
2277         /* Turn quotas off */
2278         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2279                 if (sb_dqopt(sb)->files[i])
2280                         dquot_quota_off(sb, i);
2281         }
2282 #endif
2283         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2284 }
2285
2286 /*
2287  * Maximal extent format file size.
2288  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2289  * extent format containers, within a sector_t, and within i_blocks
2290  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2291  * so that won't be a limiting factor.
2292  *
2293  * However there is other limiting factor. We do store extents in the form
2294  * of starting block and length, hence the resulting length of the extent
2295  * covering maximum file size must fit into on-disk format containers as
2296  * well. Given that length is always by 1 unit bigger than max unit (because
2297  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2298  *
2299  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2300  */
2301 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2302 {
2303         loff_t res;
2304         loff_t upper_limit = MAX_LFS_FILESIZE;
2305
2306         /* small i_blocks in vfs inode? */
2307         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2308                 /*
2309                  * CONFIG_LBDAF is not enabled implies the inode
2310                  * i_block represent total blocks in 512 bytes
2311                  * 32 == size of vfs inode i_blocks * 8
2312                  */
2313                 upper_limit = (1LL << 32) - 1;
2314
2315                 /* total blocks in file system block size */
2316                 upper_limit >>= (blkbits - 9);
2317                 upper_limit <<= blkbits;
2318         }
2319
2320         /*
2321          * 32-bit extent-start container, ee_block. We lower the maxbytes
2322          * by one fs block, so ee_len can cover the extent of maximum file
2323          * size
2324          */
2325         res = (1LL << 32) - 1;
2326         res <<= blkbits;
2327
2328         /* Sanity check against vm- & vfs- imposed limits */
2329         if (res > upper_limit)
2330                 res = upper_limit;
2331
2332         return res;
2333 }
2334
2335 /*
2336  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2337  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2338  * We need to be 1 filesystem block less than the 2^48 sector limit.
2339  */
2340 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2341 {
2342         loff_t res = EXT4_NDIR_BLOCKS;
2343         int meta_blocks;
2344         loff_t upper_limit;
2345         /* This is calculated to be the largest file size for a dense, block
2346          * mapped file such that the file's total number of 512-byte sectors,
2347          * including data and all indirect blocks, does not exceed (2^48 - 1).
2348          *
2349          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2350          * number of 512-byte sectors of the file.
2351          */
2352
2353         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2354                 /*
2355                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2356                  * the inode i_block field represents total file blocks in
2357                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2358                  */
2359                 upper_limit = (1LL << 32) - 1;
2360
2361                 /* total blocks in file system block size */
2362                 upper_limit >>= (bits - 9);
2363
2364         } else {
2365                 /*
2366                  * We use 48 bit ext4_inode i_blocks
2367                  * With EXT4_HUGE_FILE_FL set the i_blocks
2368                  * represent total number of blocks in
2369                  * file system block size
2370                  */
2371                 upper_limit = (1LL << 48) - 1;
2372
2373         }
2374
2375         /* indirect blocks */
2376         meta_blocks = 1;
2377         /* double indirect blocks */
2378         meta_blocks += 1 + (1LL << (bits-2));
2379         /* tripple indirect blocks */
2380         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2381
2382         upper_limit -= meta_blocks;
2383         upper_limit <<= bits;
2384
2385         res += 1LL << (bits-2);
2386         res += 1LL << (2*(bits-2));
2387         res += 1LL << (3*(bits-2));
2388         res <<= bits;
2389         if (res > upper_limit)
2390                 res = upper_limit;
2391
2392         if (res > MAX_LFS_FILESIZE)
2393                 res = MAX_LFS_FILESIZE;
2394
2395         return res;
2396 }
2397
2398 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2399                                    ext4_fsblk_t logical_sb_block, int nr)
2400 {
2401         struct ext4_sb_info *sbi = EXT4_SB(sb);
2402         ext4_group_t bg, first_meta_bg;
2403         int has_super = 0;
2404
2405         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2406
2407         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2408                 return logical_sb_block + nr + 1;
2409         bg = sbi->s_desc_per_block * nr;
2410         if (ext4_bg_has_super(sb, bg))
2411                 has_super = 1;
2412
2413         /*
2414          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2415          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2416          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2417          * compensate.
2418          */
2419         if (sb->s_blocksize == 1024 && nr == 0 &&
2420             le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block) == 0)
2421                 has_super++;
2422
2423         return (has_super + ext4_group_first_block_no(sb, bg));
2424 }
2425
2426 /**
2427  * ext4_get_stripe_size: Get the stripe size.
2428  * @sbi: In memory super block info
2429  *
2430  * If we have specified it via mount option, then
2431  * use the mount option value. If the value specified at mount time is
2432  * greater than the blocks per group use the super block value.
2433  * If the super block value is greater than blocks per group return 0.
2434  * Allocator needs it be less than blocks per group.
2435  *
2436  */
2437 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2438 {
2439         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2440         unsigned long stripe_width =
2441                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2442         int ret;
2443
2444         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2445                 ret = sbi->s_stripe;
2446         else if (stripe_width <= sbi->s_blocks_per_group)
2447                 ret = stripe_width;
2448         else if (stride <= sbi->s_blocks_per_group)
2449                 ret = stride;
2450         else
2451                 ret = 0;
2452
2453         /*
2454          * If the stripe width is 1, this makes no sense and
2455          * we set it to 0 to turn off stripe handling code.
2456          */
2457         if (ret <= 1)
2458                 ret = 0;
2459
2460         return ret;
2461 }
2462
2463 /*
2464  * Check whether this filesystem can be mounted based on
2465  * the features present and the RDONLY/RDWR mount requested.
2466  * Returns 1 if this filesystem can be mounted as requested,
2467  * 0 if it cannot be.
2468  */
2469 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2470 {
2471         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2472                 ext4_msg(sb, KERN_ERR,
2473                         "Couldn't mount because of "
2474                         "unsupported optional features (%x)",
2475                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2476                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2477                 return 0;
2478         }
2479
2480         if (readonly)
2481                 return 1;
2482
2483         if (ext4_has_feature_readonly(sb)) {
2484                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2485                 sb->s_flags |= MS_RDONLY;
2486                 return 1;
2487         }
2488
2489         /* Check that feature set is OK for a read-write mount */
2490         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2491                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2492                          "unsupported optional features (%x)",
2493                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2494                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2495                 return 0;
2496         }
2497         /*
2498          * Large file size enabled file system can only be mounted
2499          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2500          */
2501         if (ext4_has_feature_huge_file(sb)) {
2502                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2503                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2504                                  "cannot be mounted RDWR without "
2505                                  "CONFIG_LBDAF");
2506                         return 0;
2507                 }
2508         }
2509         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2510                 ext4_msg(sb, KERN_ERR,
2511                          "Can't support bigalloc feature without "
2512                          "extents feature\n");
2513                 return 0;
2514         }
2515
2516 #ifndef CONFIG_QUOTA
2517         if (ext4_has_feature_quota(sb) && !readonly) {
2518                 ext4_msg(sb, KERN_ERR,
2519                          "Filesystem with quota feature cannot be mounted RDWR "
2520                          "without CONFIG_QUOTA");
2521                 return 0;
2522         }
2523 #endif  /* CONFIG_QUOTA */
2524         return 1;
2525 }
2526
2527 /*
2528  * This function is called once a day if we have errors logged
2529  * on the file system
2530  */
2531 static void print_daily_error_info(unsigned long arg)
2532 {
2533         struct super_block *sb = (struct super_block *) arg;
2534         struct ext4_sb_info *sbi;
2535         struct ext4_super_block *es;
2536
2537         sbi = EXT4_SB(sb);
2538         es = sbi->s_es;
2539
2540         if (es->s_error_count)
2541                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2542                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2543                          le32_to_cpu(es->s_error_count));
2544         if (es->s_first_error_time) {
2545                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %u: %.*s:%d",
2546                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2547                        (int) sizeof(es->s_first_error_func),
2548                        es->s_first_error_func,
2549                        le32_to_cpu(es->s_first_error_line));
2550                 if (es->s_first_error_ino)
2551                         printk(": inode %u",
2552                                le32_to_cpu(es->s_first_error_ino));
2553                 if (es->s_first_error_block)
2554                         printk(": block %llu", (unsigned long long)
2555                                le64_to_cpu(es->s_first_error_block));
2556                 printk("\n");
2557         }
2558         if (es->s_last_error_time) {
2559                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %u: %.*s:%d",
2560                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2561                        (int) sizeof(es->s_last_error_func),
2562                        es->s_last_error_func,
2563                        le32_to_cpu(es->s_last_error_line));
2564                 if (es->s_last_error_ino)
2565                         printk(": inode %u",
2566                                le32_to_cpu(es->s_last_error_ino));
2567                 if (es->s_last_error_block)
2568                         printk(": block %llu", (unsigned long long)
2569                                le64_to_cpu(es->s_last_error_block));
2570                 printk("\n");
2571         }
2572         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2573 }
2574
2575 /* Find next suitable group and run ext4_init_inode_table */
2576 static int ext4_run_li_request(struct ext4_li_request *elr)
2577 {
2578         struct ext4_group_desc *gdp = NULL;
2579         ext4_group_t group, ngroups;
2580         struct super_block *sb;
2581         unsigned long timeout = 0;
2582         int ret = 0;
2583
2584         sb = elr->lr_super;
2585         ngroups = EXT4_SB(sb)->s_groups_count;
2586
2587         sb_start_write(sb);
2588         for (group = elr->lr_next_group; group < ngroups; group++) {
2589                 gdp = ext4_get_group_desc(sb, group, NULL);
2590                 if (!gdp) {
2591                         ret = 1;
2592                         break;
2593                 }
2594
2595                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2596                         break;
2597         }
2598
2599         if (group >= ngroups)
2600                 ret = 1;
2601
2602         if (!ret) {
2603                 timeout = jiffies;
2604                 ret = ext4_init_inode_table(sb, group,
2605                                             elr->lr_timeout ? 0 : 1);
2606                 if (elr->lr_timeout == 0) {
2607                         timeout = (jiffies - timeout) *
2608                                   elr->lr_sbi->s_li_wait_mult;
2609                         elr->lr_timeout = timeout;
2610                 }
2611                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2612                 elr->lr_next_group = group + 1;
2613         }
2614         sb_end_write(sb);
2615
2616         return ret;
2617 }
2618
2619 /*
2620  * Remove lr_request from the list_request and free the
2621  * request structure. Should be called with li_list_mtx held
2622  */
2623 static void ext4_remove_li_request(struct ext4_li_request *elr)
2624 {
2625         struct ext4_sb_info *sbi;
2626
2627         if (!elr)
2628                 return;
2629
2630         sbi = elr->lr_sbi;
2631
2632         list_del(&elr->lr_request);
2633         sbi->s_li_request = NULL;
2634         kfree(elr);
2635 }
2636
2637 static void ext4_unregister_li_request(struct super_block *sb)
2638 {
2639         mutex_lock(&ext4_li_mtx);
2640         if (!ext4_li_info) {
2641                 mutex_unlock(&ext4_li_mtx);
2642                 return;
2643         }
2644
2645         mutex_lock(&ext4_li_info->li_list_mtx);
2646         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2647         mutex_unlock(&ext4_li_info->li_list_mtx);
2648         mutex_unlock(&ext4_li_mtx);
2649 }
2650
2651 static struct task_struct *ext4_lazyinit_task;
2652
2653 /*
2654  * This is the function where ext4lazyinit thread lives. It walks
2655  * through the request list searching for next scheduled filesystem.
2656  * When such a fs is found, run the lazy initialization request
2657  * (ext4_rn_li_request) and keep track of the time spend in this
2658  * function. Based on that time we compute next schedule time of
2659  * the request. When walking through the list is complete, compute
2660  * next waking time and put itself into sleep.
2661  */
2662 static int ext4_lazyinit_thread(void *arg)
2663 {
2664         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2665         struct list_head *pos, *n;
2666         struct ext4_li_request *elr;
2667         unsigned long next_wakeup, cur;
2668
2669         BUG_ON(NULL == eli);
2670
2671 cont_thread:
2672         while (true) {
2673                 next_wakeup = MAX_JIFFY_OFFSET;
2674
2675                 mutex_lock(&eli->li_list_mtx);
2676                 if (list_empty(&eli->li_request_list)) {
2677                         mutex_unlock(&eli->li_list_mtx);
2678                         goto exit_thread;
2679                 }
2680
2681                 list_for_each_safe(pos, n, &eli->li_request_list) {
2682                         elr = list_entry(pos, struct ext4_li_request,
2683                                          lr_request);
2684
2685                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2686                                 if (ext4_run_li_request(elr) != 0) {
2687                                         /* error, remove the lazy_init job */
2688                                         ext4_remove_li_request(elr);
2689                                         continue;
2690                                 }
2691                         }
2692
2693                         if (time_before(elr->lr_next_sched, next_wakeup))
2694                                 next_wakeup = elr->lr_next_sched;
2695                 }
2696                 mutex_unlock(&eli->li_list_mtx);
2697
2698                 try_to_freeze();
2699
2700                 cur = jiffies;
2701                 if ((time_after_eq(cur, next_wakeup)) ||
2702                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2703                         cond_resched();
2704                         continue;
2705                 }
2706
2707                 schedule_timeout_interruptible(next_wakeup - cur);
2708
2709                 if (kthread_should_stop()) {
2710                         ext4_clear_request_list();
2711                         goto exit_thread;
2712                 }
2713         }
2714
2715 exit_thread:
2716         /*
2717          * It looks like the request list is empty, but we need
2718          * to check it under the li_list_mtx lock, to prevent any
2719          * additions into it, and of course we should lock ext4_li_mtx
2720          * to atomically free the list and ext4_li_info, because at
2721          * this point another ext4 filesystem could be registering
2722          * new one.
2723          */
2724         mutex_lock(&ext4_li_mtx);
2725         mutex_lock(&eli->li_list_mtx);
2726         if (!list_empty(&eli->li_request_list)) {
2727                 mutex_unlock(&eli->li_list_mtx);
2728                 mutex_unlock(&ext4_li_mtx);
2729                 goto cont_thread;
2730         }
2731         mutex_unlock(&eli->li_list_mtx);
2732         kfree(ext4_li_info);
2733         ext4_li_info = NULL;
2734         mutex_unlock(&ext4_li_mtx);
2735
2736         return 0;
2737 }
2738
2739 static void ext4_clear_request_list(void)
2740 {
2741         struct list_head *pos, *n;
2742         struct ext4_li_request *elr;
2743
2744         mutex_lock(&ext4_li_info->li_list_mtx);
2745         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2746                 elr = list_entry(pos, struct ext4_li_request,
2747                                  lr_request);
2748                 ext4_remove_li_request(elr);
2749         }
2750         mutex_unlock(&ext4_li_info->li_list_mtx);
2751 }
2752
2753 static int ext4_run_lazyinit_thread(void)
2754 {
2755         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
2756                                          ext4_li_info, "ext4lazyinit");
2757         if (IS_ERR(ext4_lazyinit_task)) {
2758                 int err = PTR_ERR(ext4_lazyinit_task);
2759                 ext4_clear_request_list();
2760                 kfree(ext4_li_info);
2761                 ext4_li_info = NULL;
2762                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
2763                                  "initialization thread\n",
2764                                  err);
2765                 return err;
2766         }
2767         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2768         return 0;
2769 }
2770
2771 /*
2772  * Check whether it make sense to run itable init. thread or not.
2773  * If there is at least one uninitialized inode table, return
2774  * corresponding group number, else the loop goes through all
2775  * groups and return total number of groups.
2776  */
2777 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2778 {
2779         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2780         struct ext4_group_desc *gdp = NULL;
2781
2782         for (group = 0; group < ngroups; group++) {
2783                 gdp = ext4_get_group_desc(sb, group, NULL);
2784                 if (!gdp)
2785                         continue;
2786
2787                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2788                         break;
2789         }
2790
2791         return group;
2792 }
2793
2794 static int ext4_li_info_new(void)
2795 {
2796         struct ext4_lazy_init *eli = NULL;
2797
2798         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2799         if (!eli)
2800                 return -ENOMEM;
2801
2802         INIT_LIST_HEAD(&eli->li_request_list);
2803         mutex_init(&eli->li_list_mtx);
2804
2805         eli->li_state |= EXT4_LAZYINIT_QUIT;
2806
2807         ext4_li_info = eli;
2808
2809         return 0;
2810 }
2811
2812 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2813                                             ext4_group_t start)
2814 {
2815         struct ext4_sb_info *sbi = EXT4_SB(sb);
2816         struct ext4_li_request *elr;
2817
2818         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
2819         if (!elr)
2820                 return NULL;
2821
2822         elr->lr_super = sb;
2823         elr->lr_sbi = sbi;
2824         elr->lr_next_group = start;
2825
2826         /*
2827          * Randomize first schedule time of the request to
2828          * spread the inode table initialization requests
2829          * better.
2830          */
2831         elr->lr_next_sched = jiffies + (prandom_u32() %
2832                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
2833         return elr;
2834 }
2835
2836 int ext4_register_li_request(struct super_block *sb,
2837                              ext4_group_t first_not_zeroed)
2838 {
2839         struct ext4_sb_info *sbi = EXT4_SB(sb);
2840         struct ext4_li_request *elr = NULL;
2841         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
2842         int ret = 0;
2843
2844         mutex_lock(&ext4_li_mtx);
2845         if (sbi->s_li_request != NULL) {
2846                 /*
2847                  * Reset timeout so it can be computed again, because
2848                  * s_li_wait_mult might have changed.
2849                  */
2850                 sbi->s_li_request->lr_timeout = 0;
2851                 goto out;
2852         }
2853
2854         if (first_not_zeroed == ngroups ||
2855             (sb->s_flags & MS_RDONLY) ||
2856             !test_opt(sb, INIT_INODE_TABLE))
2857                 goto out;
2858
2859         elr = ext4_li_request_new(sb, first_not_zeroed);
2860         if (!elr) {
2861                 ret = -ENOMEM;
2862                 goto out;
2863         }
2864
2865         if (NULL == ext4_li_info) {
2866                 ret = ext4_li_info_new();
2867                 if (ret)
2868                         goto out;
2869         }
2870
2871         mutex_lock(&ext4_li_info->li_list_mtx);
2872         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
2873         mutex_unlock(&ext4_li_info->li_list_mtx);
2874
2875         sbi->s_li_request = elr;
2876         /*
2877          * set elr to NULL here since it has been inserted to
2878          * the request_list and the removal and free of it is
2879          * handled by ext4_clear_request_list from now on.
2880          */
2881         elr = NULL;
2882
2883         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
2884                 ret = ext4_run_lazyinit_thread();
2885                 if (ret)
2886                         goto out;
2887         }
2888 out:
2889         mutex_unlock(&ext4_li_mtx);
2890         if (ret)
2891                 kfree(elr);
2892         return ret;
2893 }
2894
2895 /*
2896  * We do not need to lock anything since this is called on
2897  * module unload.
2898  */
2899 static void ext4_destroy_lazyinit_thread(void)
2900 {
2901         /*
2902          * If thread exited earlier
2903          * there's nothing to be done.
2904          */
2905         if (!ext4_li_info || !ext4_lazyinit_task)
2906                 return;
2907
2908         kthread_stop(ext4_lazyinit_task);
2909 }
2910
2911 static int set_journal_csum_feature_set(struct super_block *sb)
2912 {
2913         int ret = 1;
2914         int compat, incompat;
2915         struct ext4_sb_info *sbi = EXT4_SB(sb);
2916
2917         if (ext4_has_metadata_csum(sb)) {
2918                 /* journal checksum v3 */
2919                 compat = 0;
2920                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
2921         } else {
2922                 /* journal checksum v1 */
2923                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
2924                 incompat = 0;
2925         }
2926
2927         jbd2_journal_clear_features(sbi->s_journal,
2928                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2929                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
2930                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
2931         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2932                 ret = jbd2_journal_set_features(sbi->s_journal,
2933                                 compat, 0,
2934                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
2935                                 incompat);
2936         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2937                 ret = jbd2_journal_set_features(sbi->s_journal,
2938                                 compat, 0,
2939                                 incompat);
2940                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2941                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2942         } else {
2943                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2944                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2945         }
2946
2947         return ret;
2948 }
2949
2950 /*
2951  * Note: calculating the overhead so we can be compatible with
2952  * historical BSD practice is quite difficult in the face of
2953  * clusters/bigalloc.  This is because multiple metadata blocks from
2954  * different block group can end up in the same allocation cluster.
2955  * Calculating the exact overhead in the face of clustered allocation
2956  * requires either O(all block bitmaps) in memory or O(number of block
2957  * groups**2) in time.  We will still calculate the superblock for
2958  * older file systems --- and if we come across with a bigalloc file
2959  * system with zero in s_overhead_clusters the estimate will be close to
2960  * correct especially for very large cluster sizes --- but for newer
2961  * file systems, it's better to calculate this figure once at mkfs
2962  * time, and store it in the superblock.  If the superblock value is
2963  * present (even for non-bigalloc file systems), we will use it.
2964  */
2965 static int count_overhead(struct super_block *sb, ext4_group_t grp,
2966                           char *buf)
2967 {
2968         struct ext4_sb_info     *sbi = EXT4_SB(sb);
2969         struct ext4_group_desc  *gdp;
2970         ext4_fsblk_t            first_block, last_block, b;
2971         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
2972         int                     s, j, count = 0;
2973
2974         if (!ext4_has_feature_bigalloc(sb))
2975                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
2976                         sbi->s_itb_per_group + 2);
2977
2978         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
2979                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
2980         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
2981         for (i = 0; i < ngroups; i++) {
2982                 gdp = ext4_get_group_desc(sb, i, NULL);
2983                 b = ext4_block_bitmap(sb, gdp);
2984                 if (b >= first_block && b <= last_block) {
2985                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
2986                         count++;
2987                 }
2988                 b = ext4_inode_bitmap(sb, gdp);
2989                 if (b >= first_block && b <= last_block) {
2990                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
2991                         count++;
2992                 }
2993                 b = ext4_inode_table(sb, gdp);
2994                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
2995                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
2996                                 int c = EXT4_B2C(sbi, b - first_block);
2997                                 ext4_set_bit(c, buf);
2998                                 count++;
2999                         }
3000                 if (i != grp)
3001                         continue;
3002                 s = 0;
3003                 if (ext4_bg_has_super(sb, grp)) {
3004                         ext4_set_bit(s++, buf);
3005                         count++;
3006                 }
3007                 for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) {
3008                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3009                         count++;
3010                 }
3011         }
3012         if (!count)
3013                 return 0;
3014         return EXT4_CLUSTERS_PER_GROUP(sb) -
3015                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3016 }
3017
3018 /*
3019  * Compute the overhead and stash it in sbi->s_overhead
3020  */
3021 int ext4_calculate_overhead(struct super_block *sb)
3022 {
3023         struct ext4_sb_info *sbi = EXT4_SB(sb);
3024         struct ext4_super_block *es = sbi->s_es;
3025         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3026         ext4_fsblk_t overhead = 0;
3027         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3028
3029         if (!buf)
3030                 return -ENOMEM;
3031
3032         /*
3033          * Compute the overhead (FS structures).  This is constant
3034          * for a given filesystem unless the number of block groups
3035          * changes so we cache the previous value until it does.
3036          */
3037
3038         /*
3039          * All of the blocks before first_data_block are overhead
3040          */
3041         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3042
3043         /*
3044          * Add the overhead found in each block group
3045          */
3046         for (i = 0; i < ngroups; i++) {
3047                 int blks;
3048
3049                 blks = count_overhead(sb, i, buf);
3050                 overhead += blks;
3051                 if (blks)
3052                         memset(buf, 0, PAGE_SIZE);
3053                 cond_resched();
3054         }
3055         /* Add the internal journal blocks as well */
3056         if (sbi->s_journal && !sbi->journal_bdev)
3057                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3058
3059         sbi->s_overhead = overhead;
3060         smp_wmb();
3061         free_page((unsigned long) buf);
3062         return 0;
3063 }
3064
3065 static void ext4_set_resv_clusters(struct super_block *sb)
3066 {
3067         ext4_fsblk_t resv_clusters;
3068         struct ext4_sb_info *sbi = EXT4_SB(sb);
3069
3070         /*
3071          * There's no need to reserve anything when we aren't using extents.
3072          * The space estimates are exact, there are no unwritten extents,
3073          * hole punching doesn't need new metadata... This is needed especially
3074          * to keep ext2/3 backward compatibility.
3075          */
3076         if (!ext4_has_feature_extents(sb))
3077                 return;
3078         /*
3079          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3080          * This should cover the situations where we can not afford to run
3081          * out of space like for example punch hole, or converting
3082          * unwritten extents in delalloc path. In most cases such
3083          * allocation would require 1, or 2 blocks, higher numbers are
3084          * very rare.
3085          */
3086         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3087                          sbi->s_cluster_bits);
3088
3089         do_div(resv_clusters, 50);
3090         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3091
3092         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3093 }
3094
3095 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3096 {
3097         char *orig_data = kstrdup(data, GFP_KERNEL);
3098         struct buffer_head *bh;
3099         struct ext4_super_block *es = NULL;
3100         struct ext4_sb_info *sbi;
3101         ext4_fsblk_t block;
3102         ext4_fsblk_t sb_block = get_sb_block(&data);
3103         ext4_fsblk_t logical_sb_block;
3104         unsigned long offset = 0;
3105         unsigned long journal_devnum = 0;
3106         unsigned long def_mount_opts;
3107         struct inode *root;
3108         const char *descr;
3109         int ret = -ENOMEM;
3110         int blocksize, clustersize;
3111         unsigned int db_count;
3112         unsigned int i;
3113         int needs_recovery, has_huge_files, has_bigalloc;
3114         __u64 blocks_count;
3115         int err = 0;
3116         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3117         ext4_group_t first_not_zeroed;
3118
3119         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3120         if (!sbi)
3121                 goto out_free_orig;
3122
3123         sbi->s_blockgroup_lock =
3124                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3125         if (!sbi->s_blockgroup_lock) {
3126                 kfree(sbi);
3127                 goto out_free_orig;
3128         }
3129         sb->s_fs_info = sbi;
3130         sbi->s_sb = sb;
3131         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3132         sbi->s_sb_block = sb_block;
3133         if (sb->s_bdev->bd_part)
3134                 sbi->s_sectors_written_start =
3135                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3136
3137         /* Cleanup superblock name */
3138         strreplace(sb->s_id, '/', '!');
3139
3140         /* -EINVAL is default */
3141         ret = -EINVAL;
3142         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3143         if (!blocksize) {
3144                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3145                 goto out_fail;
3146         }
3147
3148         /*
3149          * The ext4 superblock will not be buffer aligned for other than 1kB
3150          * block sizes.  We need to calculate the offset from buffer start.
3151          */
3152         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3153                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3154                 offset = do_div(logical_sb_block, blocksize);
3155         } else {
3156                 logical_sb_block = sb_block;
3157         }
3158
3159         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3160                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3161                 goto out_fail;
3162         }
3163         /*
3164          * Note: s_es must be initialized as soon as possible because
3165          *       some ext4 macro-instructions depend on its value
3166          */
3167         es = (struct ext4_super_block *) (bh->b_data + offset);
3168         sbi->s_es = es;
3169         sb->s_magic = le16_to_cpu(es->s_magic);
3170         if (sb->s_magic != EXT4_SUPER_MAGIC)
3171                 goto cantfind_ext4;
3172         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3173
3174         /* Warn if metadata_csum and gdt_csum are both set. */
3175         if (ext4_has_feature_metadata_csum(sb) &&
3176             ext4_has_feature_gdt_csum(sb))
3177                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3178                              "redundant flags; please run fsck.");
3179
3180         /* Check for a known checksum algorithm */
3181         if (!ext4_verify_csum_type(sb, es)) {
3182                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3183                          "unknown checksum algorithm.");
3184                 silent = 1;
3185                 goto cantfind_ext4;
3186         }
3187
3188         /* Load the checksum driver */
3189         if (ext4_has_feature_metadata_csum(sb)) {
3190                 sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3191                 if (IS_ERR(sbi->s_chksum_driver)) {
3192                         ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3193                         ret = PTR_ERR(sbi->s_chksum_driver);
3194                         sbi->s_chksum_driver = NULL;
3195                         goto failed_mount;
3196                 }
3197         }
3198
3199         /* Check superblock checksum */
3200         if (!ext4_superblock_csum_verify(sb, es)) {
3201                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3202                          "invalid superblock checksum.  Run e2fsck?");
3203                 silent = 1;
3204                 ret = -EFSBADCRC;
3205                 goto cantfind_ext4;
3206         }
3207
3208         /* Precompute checksum seed for all metadata */
3209         if (ext4_has_feature_csum_seed(sb))
3210                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3211         else if (ext4_has_metadata_csum(sb))
3212                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3213                                                sizeof(es->s_uuid));
3214
3215         /* Set defaults before we parse the mount options */
3216         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3217         set_opt(sb, INIT_INODE_TABLE);
3218         if (def_mount_opts & EXT4_DEFM_DEBUG)
3219                 set_opt(sb, DEBUG);
3220         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3221                 set_opt(sb, GRPID);
3222         if (def_mount_opts & EXT4_DEFM_UID16)
3223                 set_opt(sb, NO_UID32);
3224         /* xattr user namespace & acls are now defaulted on */
3225         set_opt(sb, XATTR_USER);
3226 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3227         set_opt(sb, POSIX_ACL);
3228 #endif
3229         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3230         if (ext4_has_metadata_csum(sb))
3231                 set_opt(sb, JOURNAL_CHECKSUM);
3232
3233         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3234                 set_opt(sb, JOURNAL_DATA);
3235         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3236                 set_opt(sb, ORDERED_DATA);
3237         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3238                 set_opt(sb, WRITEBACK_DATA);
3239
3240         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3241                 set_opt(sb, ERRORS_PANIC);
3242         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3243                 set_opt(sb, ERRORS_CONT);
3244         else
3245                 set_opt(sb, ERRORS_RO);
3246         /* block_validity enabled by default; disable with noblock_validity */
3247         set_opt(sb, BLOCK_VALIDITY);
3248         if (def_mount_opts & EXT4_DEFM_DISCARD)
3249                 set_opt(sb, DISCARD);
3250
3251         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3252         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3253         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3254         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3255         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3256
3257         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3258                 set_opt(sb, BARRIER);
3259
3260         /*
3261          * enable delayed allocation by default
3262          * Use -o nodelalloc to turn it off
3263          */
3264         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3265             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3266                 set_opt(sb, DELALLOC);
3267
3268         /*
3269          * set default s_li_wait_mult for lazyinit, for the case there is
3270          * no mount option specified.
3271          */
3272         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3273
3274         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3275                            &journal_devnum, &journal_ioprio, 0)) {
3276                 ext4_msg(sb, KERN_WARNING,
3277                          "failed to parse options in superblock: %s",
3278                          sbi->s_es->s_mount_opts);
3279         }
3280         sbi->s_def_mount_opt = sbi->s_mount_opt;
3281         if (!parse_options((char *) data, sb, &journal_devnum,
3282                            &journal_ioprio, 0))
3283                 goto failed_mount;
3284
3285         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3286                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3287                             "with data=journal disables delayed "
3288                             "allocation and O_DIRECT support!\n");
3289                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3290                         ext4_msg(sb, KERN_ERR, "can't mount with "
3291                                  "both data=journal and delalloc");
3292                         goto failed_mount;
3293                 }
3294                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3295                         ext4_msg(sb, KERN_ERR, "can't mount with "
3296                                  "both data=journal and dioread_nolock");
3297                         goto failed_mount;
3298                 }
3299                 if (test_opt(sb, DAX)) {
3300                         ext4_msg(sb, KERN_ERR, "can't mount with "
3301                                  "both data=journal and dax");
3302                         goto failed_mount;
3303                 }
3304                 if (test_opt(sb, DELALLOC))
3305                         clear_opt(sb, DELALLOC);
3306         } else {
3307                 sb->s_iflags |= SB_I_CGROUPWB;
3308         }
3309
3310         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3311                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3312
3313         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3314             (ext4_has_compat_features(sb) ||
3315              ext4_has_ro_compat_features(sb) ||
3316              ext4_has_incompat_features(sb)))
3317                 ext4_msg(sb, KERN_WARNING,
3318                        "feature flags set on rev 0 fs, "
3319                        "running e2fsck is recommended");
3320
3321         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3322                 set_opt2(sb, HURD_COMPAT);
3323                 if (ext4_has_feature_64bit(sb)) {
3324                         ext4_msg(sb, KERN_ERR,
3325                                  "The Hurd can't support 64-bit file systems");
3326                         goto failed_mount;
3327                 }
3328         }
3329
3330         if (IS_EXT2_SB(sb)) {
3331                 if (ext2_feature_set_ok(sb))
3332                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3333                                  "using the ext4 subsystem");
3334                 else {
3335                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3336                                  "to feature incompatibilities");
3337                         goto failed_mount;
3338                 }
3339         }
3340
3341         if (IS_EXT3_SB(sb)) {
3342                 if (ext3_feature_set_ok(sb))
3343                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3344                                  "using the ext4 subsystem");
3345                 else {
3346                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3347                                  "to feature incompatibilities");
3348                         goto failed_mount;
3349                 }
3350         }
3351
3352         /*
3353          * Check feature flags regardless of the revision level, since we
3354          * previously didn't change the revision level when setting the flags,
3355          * so there is a chance incompat flags are set on a rev 0 filesystem.
3356          */
3357         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3358                 goto failed_mount;
3359
3360         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3361         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3362             blocksize > EXT4_MAX_BLOCK_SIZE) {
3363                 ext4_msg(sb, KERN_ERR,
3364                        "Unsupported filesystem blocksize %d", blocksize);
3365                 goto failed_mount;
3366         }
3367
3368         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3369                 if (blocksize != PAGE_SIZE) {
3370                         ext4_msg(sb, KERN_ERR,
3371                                         "error: unsupported blocksize for dax");
3372                         goto failed_mount;
3373                 }
3374                 if (!sb->s_bdev->bd_disk->fops->direct_access) {
3375                         ext4_msg(sb, KERN_ERR,
3376                                         "error: device does not support dax");
3377                         goto failed_mount;
3378                 }
3379         }
3380
3381         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
3382                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
3383                          es->s_encryption_level);
3384                 goto failed_mount;
3385         }
3386
3387         if (sb->s_blocksize != blocksize) {
3388                 /* Validate the filesystem blocksize */
3389                 if (!sb_set_blocksize(sb, blocksize)) {
3390                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3391                                         blocksize);
3392                         goto failed_mount;
3393                 }
3394
3395                 brelse(bh);
3396                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3397                 offset = do_div(logical_sb_block, blocksize);
3398                 bh = sb_bread_unmovable(sb, logical_sb_block);
3399                 if (!bh) {
3400                         ext4_msg(sb, KERN_ERR,
3401                                "Can't read superblock on 2nd try");
3402                         goto failed_mount;
3403                 }
3404                 es = (struct ext4_super_block *)(bh->b_data + offset);
3405                 sbi->s_es = es;
3406                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3407                         ext4_msg(sb, KERN_ERR,
3408                                "Magic mismatch, very weird!");
3409                         goto failed_mount;
3410                 }
3411         }
3412
3413         has_huge_files = ext4_has_feature_huge_file(sb);
3414         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3415                                                       has_huge_files);
3416         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3417
3418         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3419                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3420                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3421         } else {
3422                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3423                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3424                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3425                     (!is_power_of_2(sbi->s_inode_size)) ||
3426                     (sbi->s_inode_size > blocksize)) {
3427                         ext4_msg(sb, KERN_ERR,
3428                                "unsupported inode size: %d",
3429                                sbi->s_inode_size);
3430                         goto failed_mount;
3431                 }
3432                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3433                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3434         }
3435
3436         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3437         if (ext4_has_feature_64bit(sb)) {
3438                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3439                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3440                     !is_power_of_2(sbi->s_desc_size)) {
3441                         ext4_msg(sb, KERN_ERR,
3442                                "unsupported descriptor size %lu",
3443                                sbi->s_desc_size);
3444                         goto failed_mount;
3445                 }
3446         } else
3447                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3448
3449         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3450         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3451         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3452                 goto cantfind_ext4;
3453
3454         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3455         if (sbi->s_inodes_per_block == 0)
3456                 goto cantfind_ext4;
3457         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3458                                         sbi->s_inodes_per_block;
3459         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3460         sbi->s_sbh = bh;
3461         sbi->s_mount_state = le16_to_cpu(es->s_state);
3462         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3463         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3464
3465         for (i = 0; i < 4; i++)
3466                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3467         sbi->s_def_hash_version = es->s_def_hash_version;
3468         if (ext4_has_feature_dir_index(sb)) {
3469                 i = le32_to_cpu(es->s_flags);
3470                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
3471                         sbi->s_hash_unsigned = 3;
3472                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3473 #ifdef __CHAR_UNSIGNED__
3474                         if (!(sb->s_flags & MS_RDONLY))
3475                                 es->s_flags |=
3476                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3477                         sbi->s_hash_unsigned = 3;
3478 #else
3479                         if (!(sb->s_flags & MS_RDONLY))
3480                                 es->s_flags |=
3481                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3482 #endif
3483                 }
3484         }
3485
3486         /* Handle clustersize */
3487         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3488         has_bigalloc = ext4_has_feature_bigalloc(sb);
3489         if (has_bigalloc) {
3490                 if (clustersize < blocksize) {
3491                         ext4_msg(sb, KERN_ERR,
3492                                  "cluster size (%d) smaller than "
3493                                  "block size (%d)", clustersize, blocksize);
3494                         goto failed_mount;
3495                 }
3496                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3497                         le32_to_cpu(es->s_log_block_size);
3498                 sbi->s_clusters_per_group =
3499                         le32_to_cpu(es->s_clusters_per_group);
3500                 if (sbi->s_clusters_per_group > blocksize * 8) {
3501                         ext4_msg(sb, KERN_ERR,
3502                                  "#clusters per group too big: %lu",
3503                                  sbi->s_clusters_per_group);
3504                         goto failed_mount;
3505                 }
3506                 if (sbi->s_blocks_per_group !=
3507                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3508                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3509                                  "clusters per group (%lu) inconsistent",
3510                                  sbi->s_blocks_per_group,
3511                                  sbi->s_clusters_per_group);
3512                         goto failed_mount;
3513                 }
3514         } else {
3515                 if (clustersize != blocksize) {
3516                         ext4_warning(sb, "fragment/cluster size (%d) != "
3517                                      "block size (%d)", clustersize,
3518                                      blocksize);
3519                         clustersize = blocksize;
3520                 }
3521                 if (sbi->s_blocks_per_group > blocksize * 8) {
3522                         ext4_msg(sb, KERN_ERR,
3523                                  "#blocks per group too big: %lu",
3524                                  sbi->s_blocks_per_group);
3525                         goto failed_mount;
3526                 }
3527                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3528                 sbi->s_cluster_bits = 0;
3529         }
3530         sbi->s_cluster_ratio = clustersize / blocksize;
3531
3532         if (sbi->s_inodes_per_group > blocksize * 8) {
3533                 ext4_msg(sb, KERN_ERR,
3534                        "#inodes per group too big: %lu",
3535                        sbi->s_inodes_per_group);
3536                 goto failed_mount;
3537         }
3538
3539         /* Do we have standard group size of clustersize * 8 blocks ? */
3540         if (sbi->s_blocks_per_group == clustersize << 3)
3541                 set_opt2(sb, STD_GROUP_SIZE);
3542
3543         /*
3544          * Test whether we have more sectors than will fit in sector_t,
3545          * and whether the max offset is addressable by the page cache.
3546          */
3547         err = generic_check_addressable(sb->s_blocksize_bits,
3548                                         ext4_blocks_count(es));
3549         if (err) {
3550                 ext4_msg(sb, KERN_ERR, "filesystem"
3551                          " too large to mount safely on this system");
3552                 if (sizeof(sector_t) < 8)
3553                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3554                 goto failed_mount;
3555         }
3556
3557         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3558                 goto cantfind_ext4;
3559
3560         /* check blocks count against device size */
3561         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3562         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3563                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3564                        "exceeds size of device (%llu blocks)",
3565                        ext4_blocks_count(es), blocks_count);
3566                 goto failed_mount;
3567         }
3568
3569         /*
3570          * It makes no sense for the first data block to be beyond the end
3571          * of the filesystem.
3572          */
3573         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3574                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3575                          "block %u is beyond end of filesystem (%llu)",
3576                          le32_to_cpu(es->s_first_data_block),
3577                          ext4_blocks_count(es));
3578                 goto failed_mount;
3579         }
3580         blocks_count = (ext4_blocks_count(es) -
3581                         le32_to_cpu(es->s_first_data_block) +
3582                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3583         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3584         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3585                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3586                        "(block count %llu, first data block %u, "
3587                        "blocks per group %lu)", sbi->s_groups_count,
3588                        ext4_blocks_count(es),
3589                        le32_to_cpu(es->s_first_data_block),
3590                        EXT4_BLOCKS_PER_GROUP(sb));
3591                 goto failed_mount;
3592         }
3593         sbi->s_groups_count = blocks_count;
3594         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3595                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3596         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3597                    EXT4_DESC_PER_BLOCK(sb);
3598         sbi->s_group_desc = ext4_kvmalloc(db_count *
3599                                           sizeof(struct buffer_head *),
3600                                           GFP_KERNEL);
3601         if (sbi->s_group_desc == NULL) {
3602                 ext4_msg(sb, KERN_ERR, "not enough memory");
3603                 ret = -ENOMEM;
3604                 goto failed_mount;
3605         }
3606
3607         bgl_lock_init(sbi->s_blockgroup_lock);
3608
3609         for (i = 0; i < db_count; i++) {
3610                 block = descriptor_loc(sb, logical_sb_block, i);
3611                 sbi->s_group_desc[i] = sb_bread_unmovable(sb, block);
3612                 if (!sbi->s_group_desc[i]) {
3613                         ext4_msg(sb, KERN_ERR,
3614                                "can't read group descriptor %d", i);
3615                         db_count = i;
3616                         goto failed_mount2;
3617                 }
3618         }
3619         if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3620                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3621                 ret = -EFSCORRUPTED;
3622                 goto failed_mount2;
3623         }
3624
3625         sbi->s_gdb_count = db_count;
3626         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3627         spin_lock_init(&sbi->s_next_gen_lock);
3628
3629         setup_timer(&sbi->s_err_report, print_daily_error_info,
3630                 (unsigned long) sb);
3631
3632         /* Register extent status tree shrinker */
3633         if (ext4_es_register_shrinker(sbi))
3634                 goto failed_mount3;
3635
3636         sbi->s_stripe = ext4_get_stripe_size(sbi);
3637         sbi->s_extent_max_zeroout_kb = 32;
3638
3639         /*
3640          * set up enough so that it can read an inode
3641          */
3642         sb->s_op = &ext4_sops;
3643         sb->s_export_op = &ext4_export_ops;
3644         sb->s_xattr = ext4_xattr_handlers;
3645 #ifdef CONFIG_QUOTA
3646         sb->dq_op = &ext4_quota_operations;
3647         if (ext4_has_feature_quota(sb))
3648                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
3649         else
3650                 sb->s_qcop = &ext4_qctl_operations;
3651         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
3652 #endif
3653         memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
3654
3655         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
3656         mutex_init(&sbi->s_orphan_lock);
3657
3658         sb->s_root = NULL;
3659
3660         needs_recovery = (es->s_last_orphan != 0 ||
3661                           ext4_has_feature_journal_needs_recovery(sb));
3662
3663         if (ext4_has_feature_mmp(sb) && !(sb->s_flags & MS_RDONLY))
3664                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
3665                         goto failed_mount3a;
3666
3667         /*
3668          * The first inode we look at is the journal inode.  Don't try
3669          * root first: it may be modified in the journal!
3670          */
3671         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
3672                 if (ext4_load_journal(sb, es, journal_devnum))
3673                         goto failed_mount3a;
3674         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
3675                    ext4_has_feature_journal_needs_recovery(sb)) {
3676                 ext4_msg(sb, KERN_ERR, "required journal recovery "
3677                        "suppressed and not mounted read-only");
3678                 goto failed_mount_wq;
3679         } else {
3680                 clear_opt(sb, DATA_FLAGS);
3681                 sbi->s_journal = NULL;
3682                 needs_recovery = 0;
3683                 goto no_journal;
3684         }
3685
3686         if (ext4_has_feature_64bit(sb) &&
3687             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
3688                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
3689                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
3690                 goto failed_mount_wq;
3691         }
3692
3693         if (!set_journal_csum_feature_set(sb)) {
3694                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
3695                          "feature set");
3696                 goto failed_mount_wq;
3697         }
3698
3699         /* We have now updated the journal if required, so we can
3700          * validate the data journaling mode. */
3701         switch (test_opt(sb, DATA_FLAGS)) {
3702         case 0:
3703                 /* No mode set, assume a default based on the journal
3704                  * capabilities: ORDERED_DATA if the journal can
3705                  * cope, else JOURNAL_DATA
3706                  */
3707                 if (jbd2_journal_check_available_features
3708                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
3709                         set_opt(sb, ORDERED_DATA);
3710                 else
3711                         set_opt(sb, JOURNAL_DATA);
3712                 break;
3713
3714         case EXT4_MOUNT_ORDERED_DATA:
3715         case EXT4_MOUNT_WRITEBACK_DATA:
3716                 if (!jbd2_journal_check_available_features
3717                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
3718                         ext4_msg(sb, KERN_ERR, "Journal does not support "
3719                                "requested data journaling mode");
3720                         goto failed_mount_wq;
3721                 }
3722         default:
3723                 break;
3724         }
3725         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3726
3727         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
3728
3729 no_journal:
3730         if (ext4_mballoc_ready) {
3731                 sbi->s_mb_cache = ext4_xattr_create_cache(sb->s_id);
3732                 if (!sbi->s_mb_cache) {
3733                         ext4_msg(sb, KERN_ERR, "Failed to create an mb_cache");
3734                         goto failed_mount_wq;
3735                 }
3736         }
3737
3738         if ((DUMMY_ENCRYPTION_ENABLED(sbi) || ext4_has_feature_encrypt(sb)) &&
3739             (blocksize != PAGE_CACHE_SIZE)) {
3740                 ext4_msg(sb, KERN_ERR,
3741                          "Unsupported blocksize for fs encryption");
3742                 goto failed_mount_wq;
3743         }
3744
3745         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !(sb->s_flags & MS_RDONLY) &&
3746             !ext4_has_feature_encrypt(sb)) {
3747                 ext4_set_feature_encrypt(sb);
3748                 ext4_commit_super(sb, 1);
3749         }
3750
3751         /*
3752          * Get the # of file system overhead blocks from the
3753          * superblock if present.
3754          */
3755         if (es->s_overhead_clusters)
3756                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
3757         else {
3758                 err = ext4_calculate_overhead(sb);
3759                 if (err)
3760                         goto failed_mount_wq;
3761         }
3762
3763         /*
3764          * The maximum number of concurrent works can be high and
3765          * concurrency isn't really necessary.  Limit it to 1.
3766          */
3767         EXT4_SB(sb)->rsv_conversion_wq =
3768                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
3769         if (!EXT4_SB(sb)->rsv_conversion_wq) {
3770                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
3771                 ret = -ENOMEM;
3772                 goto failed_mount4;
3773         }
3774
3775         /*
3776          * The jbd2_journal_load will have done any necessary log recovery,
3777          * so we can safely mount the rest of the filesystem now.
3778          */
3779
3780         root = ext4_iget(sb, EXT4_ROOT_INO);
3781         if (IS_ERR(root)) {
3782                 ext4_msg(sb, KERN_ERR, "get root inode failed");
3783                 ret = PTR_ERR(root);
3784                 root = NULL;
3785                 goto failed_mount4;
3786         }
3787         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
3788                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
3789                 iput(root);
3790                 goto failed_mount4;
3791         }
3792         sb->s_root = d_make_root(root);
3793         if (!sb->s_root) {
3794                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
3795                 ret = -ENOMEM;
3796                 goto failed_mount4;
3797         }
3798
3799         if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY))
3800                 sb->s_flags |= MS_RDONLY;
3801
3802         /* determine the minimum size of new large inodes, if present */
3803         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3804                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3805                                                      EXT4_GOOD_OLD_INODE_SIZE;
3806                 if (ext4_has_feature_extra_isize(sb)) {
3807                         if (sbi->s_want_extra_isize <
3808                             le16_to_cpu(es->s_want_extra_isize))
3809                                 sbi->s_want_extra_isize =
3810                                         le16_to_cpu(es->s_want_extra_isize);
3811                         if (sbi->s_want_extra_isize <
3812                             le16_to_cpu(es->s_min_extra_isize))
3813                                 sbi->s_want_extra_isize =
3814                                         le16_to_cpu(es->s_min_extra_isize);
3815                 }
3816         }
3817         /* Check if enough inode space is available */
3818         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3819                                                         sbi->s_inode_size) {
3820                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3821                                                        EXT4_GOOD_OLD_INODE_SIZE;
3822                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
3823                          "available");
3824         }
3825
3826         ext4_set_resv_clusters(sb);
3827
3828         err = ext4_setup_system_zone(sb);
3829         if (err) {
3830                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
3831                          "zone (%d)", err);
3832                 goto failed_mount4a;
3833         }
3834
3835         ext4_ext_init(sb);
3836         err = ext4_mb_init(sb);
3837         if (err) {
3838                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
3839                          err);
3840                 goto failed_mount5;
3841         }
3842
3843         block = ext4_count_free_clusters(sb);
3844         ext4_free_blocks_count_set(sbi->s_es,
3845                                    EXT4_C2B(sbi, block));
3846         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
3847                                   GFP_KERNEL);
3848         if (!err) {
3849                 unsigned long freei = ext4_count_free_inodes(sb);
3850                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
3851                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
3852                                           GFP_KERNEL);
3853         }
3854         if (!err)
3855                 err = percpu_counter_init(&sbi->s_dirs_counter,
3856                                           ext4_count_dirs(sb), GFP_KERNEL);
3857         if (!err)
3858                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
3859                                           GFP_KERNEL);
3860         if (err) {
3861                 ext4_msg(sb, KERN_ERR, "insufficient memory");
3862                 goto failed_mount6;
3863         }
3864
3865         if (ext4_has_feature_flex_bg(sb))
3866                 if (!ext4_fill_flex_info(sb)) {
3867                         ext4_msg(sb, KERN_ERR,
3868                                "unable to initialize "
3869                                "flex_bg meta info!");
3870                         goto failed_mount6;
3871                 }
3872
3873         err = ext4_register_li_request(sb, first_not_zeroed);
3874         if (err)
3875                 goto failed_mount6;
3876
3877         err = ext4_register_sysfs(sb);
3878         if (err)
3879                 goto failed_mount7;
3880
3881 #ifdef CONFIG_QUOTA
3882         /* Enable quota usage during mount. */
3883         if (ext4_has_feature_quota(sb) && !(sb->s_flags & MS_RDONLY)) {
3884                 err = ext4_enable_quotas(sb);
3885                 if (err)
3886                         goto failed_mount8;
3887         }
3888 #endif  /* CONFIG_QUOTA */
3889
3890         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
3891         ext4_orphan_cleanup(sb, es);
3892         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
3893         if (needs_recovery) {
3894                 ext4_msg(sb, KERN_INFO, "recovery complete");
3895                 ext4_mark_recovery_complete(sb, es);
3896         }
3897         if (EXT4_SB(sb)->s_journal) {
3898                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3899                         descr = " journalled data mode";
3900                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3901                         descr = " ordered data mode";
3902                 else
3903                         descr = " writeback data mode";
3904         } else
3905                 descr = "out journal";
3906
3907         if (test_opt(sb, DISCARD)) {
3908                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
3909                 if (!blk_queue_discard(q))
3910                         ext4_msg(sb, KERN_WARNING,
3911                                  "mounting with \"discard\" option, but "
3912                                  "the device does not support discard");
3913         }
3914
3915         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
3916                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
3917                          "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
3918                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
3919
3920         if (es->s_error_count)
3921                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
3922
3923         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
3924         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
3925         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
3926         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
3927
3928         kfree(orig_data);
3929         return 0;
3930
3931 cantfind_ext4:
3932         if (!silent)
3933                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
3934         goto failed_mount;
3935
3936 #ifdef CONFIG_QUOTA
3937 failed_mount8:
3938         ext4_unregister_sysfs(sb);
3939 #endif
3940 failed_mount7:
3941         ext4_unregister_li_request(sb);
3942 failed_mount6:
3943         ext4_mb_release(sb);
3944         if (sbi->s_flex_groups)
3945                 kvfree(sbi->s_flex_groups);
3946         percpu_counter_destroy(&sbi->s_freeclusters_counter);
3947         percpu_counter_destroy(&sbi->s_freeinodes_counter);
3948         percpu_counter_destroy(&sbi->s_dirs_counter);
3949         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
3950 failed_mount5:
3951         ext4_ext_release(sb);
3952         ext4_release_system_zone(sb);
3953 failed_mount4a:
3954         dput(sb->s_root);
3955         sb->s_root = NULL;
3956 failed_mount4:
3957         ext4_msg(sb, KERN_ERR, "mount failed");
3958         if (EXT4_SB(sb)->rsv_conversion_wq)
3959                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
3960 failed_mount_wq:
3961         if (sbi->s_journal) {
3962                 jbd2_journal_destroy(sbi->s_journal);
3963                 sbi->s_journal = NULL;
3964         }
3965 failed_mount3a:
3966         ext4_es_unregister_shrinker(sbi);
3967 failed_mount3:
3968         del_timer_sync(&sbi->s_err_report);
3969         if (sbi->s_mmp_tsk)
3970                 kthread_stop(sbi->s_mmp_tsk);
3971 failed_mount2:
3972         for (i = 0; i < db_count; i++)
3973                 brelse(sbi->s_group_desc[i]);
3974         kvfree(sbi->s_group_desc);
3975 failed_mount:
3976         if (sbi->s_chksum_driver)
3977                 crypto_free_shash(sbi->s_chksum_driver);
3978 #ifdef CONFIG_QUOTA
3979         for (i = 0; i < EXT4_MAXQUOTAS; i++)
3980                 kfree(sbi->s_qf_names[i]);
3981 #endif
3982         ext4_blkdev_remove(sbi);
3983         brelse(bh);
3984 out_fail:
3985         sb->s_fs_info = NULL;
3986         kfree(sbi->s_blockgroup_lock);
3987         kfree(sbi);
3988 out_free_orig:
3989         kfree(orig_data);
3990         return err ? err : ret;
3991 }
3992
3993 /*
3994  * Setup any per-fs journal parameters now.  We'll do this both on
3995  * initial mount, once the journal has been initialised but before we've
3996  * done any recovery; and again on any subsequent remount.
3997  */
3998 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
3999 {
4000         struct ext4_sb_info *sbi = EXT4_SB(sb);
4001
4002         journal->j_commit_interval = sbi->s_commit_interval;
4003         journal->j_min_batch_time = sbi->s_min_batch_time;
4004         journal->j_max_batch_time = sbi->s_max_batch_time;
4005
4006         write_lock(&journal->j_state_lock);
4007         if (test_opt(sb, BARRIER))
4008                 journal->j_flags |= JBD2_BARRIER;
4009         else
4010                 journal->j_flags &= ~JBD2_BARRIER;
4011         if (test_opt(sb, DATA_ERR_ABORT))
4012                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4013         else
4014                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4015         write_unlock(&journal->j_state_lock);
4016 }
4017
4018 static journal_t *ext4_get_journal(struct super_block *sb,
4019                                    unsigned int journal_inum)
4020 {
4021         struct inode *journal_inode;
4022         journal_t *journal;
4023
4024         BUG_ON(!ext4_has_feature_journal(sb));
4025
4026         /* First, test for the existence of a valid inode on disk.  Bad
4027          * things happen if we iget() an unused inode, as the subsequent
4028          * iput() will try to delete it. */
4029
4030         journal_inode = ext4_iget(sb, journal_inum);
4031         if (IS_ERR(journal_inode)) {
4032                 ext4_msg(sb, KERN_ERR, "no journal found");
4033                 return NULL;
4034         }
4035         if (!journal_inode->i_nlink) {
4036                 make_bad_inode(journal_inode);
4037                 iput(journal_inode);
4038                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4039                 return NULL;
4040         }
4041
4042         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4043                   journal_inode, journal_inode->i_size);
4044         if (!S_ISREG(journal_inode->i_mode)) {
4045                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4046                 iput(journal_inode);
4047                 return NULL;
4048         }
4049
4050         journal = jbd2_journal_init_inode(journal_inode);
4051         if (!journal) {
4052                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4053                 iput(journal_inode);
4054                 return NULL;
4055         }
4056         journal->j_private = sb;
4057         ext4_init_journal_params(sb, journal);
4058         return journal;
4059 }
4060
4061 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4062                                        dev_t j_dev)
4063 {
4064         struct buffer_head *bh;
4065         journal_t *journal;
4066         ext4_fsblk_t start;
4067         ext4_fsblk_t len;
4068         int hblock, blocksize;
4069         ext4_fsblk_t sb_block;
4070         unsigned long offset;
4071         struct ext4_super_block *es;
4072         struct block_device *bdev;
4073
4074         BUG_ON(!ext4_has_feature_journal(sb));
4075
4076         bdev = ext4_blkdev_get(j_dev, sb);
4077         if (bdev == NULL)
4078                 return NULL;
4079
4080         blocksize = sb->s_blocksize;
4081         hblock = bdev_logical_block_size(bdev);
4082         if (blocksize < hblock) {
4083                 ext4_msg(sb, KERN_ERR,
4084                         "blocksize too small for journal device");
4085                 goto out_bdev;
4086         }
4087
4088         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4089         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4090         set_blocksize(bdev, blocksize);
4091         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4092                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4093                        "external journal");
4094                 goto out_bdev;
4095         }
4096
4097         es = (struct ext4_super_block *) (bh->b_data + offset);
4098         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4099             !(le32_to_cpu(es->s_feature_incompat) &
4100               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4101                 ext4_msg(sb, KERN_ERR, "external journal has "
4102                                         "bad superblock");
4103                 brelse(bh);
4104                 goto out_bdev;
4105         }
4106
4107         if ((le32_to_cpu(es->s_feature_ro_compat) &
4108              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4109             es->s_checksum != ext4_superblock_csum(sb, es)) {
4110                 ext4_msg(sb, KERN_ERR, "external journal has "
4111                                        "corrupt superblock");
4112                 brelse(bh);
4113                 goto out_bdev;
4114         }
4115
4116         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4117                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4118                 brelse(bh);
4119                 goto out_bdev;
4120         }
4121
4122         len = ext4_blocks_count(es);
4123         start = sb_block + 1;
4124         brelse(bh);     /* we're done with the superblock */
4125
4126         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4127                                         start, len, blocksize);
4128         if (!journal) {
4129                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4130                 goto out_bdev;
4131         }
4132         journal->j_private = sb;
4133         ll_rw_block(READ | REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4134         wait_on_buffer(journal->j_sb_buffer);
4135         if (!buffer_uptodate(journal->j_sb_buffer)) {
4136                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4137                 goto out_journal;
4138         }
4139         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4140                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4141                                         "user (unsupported) - %d",
4142                         be32_to_cpu(journal->j_superblock->s_nr_users));
4143                 goto out_journal;
4144         }
4145         EXT4_SB(sb)->journal_bdev = bdev;
4146         ext4_init_journal_params(sb, journal);
4147         return journal;
4148
4149 out_journal:
4150         jbd2_journal_destroy(journal);
4151 out_bdev:
4152         ext4_blkdev_put(bdev);
4153         return NULL;
4154 }
4155
4156 static int ext4_load_journal(struct super_block *sb,
4157                              struct ext4_super_block *es,
4158                              unsigned long journal_devnum)
4159 {
4160         journal_t *journal;
4161         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4162         dev_t journal_dev;
4163         int err = 0;
4164         int really_read_only;
4165
4166         BUG_ON(!ext4_has_feature_journal(sb));
4167
4168         if (journal_devnum &&
4169             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4170                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4171                         "numbers have changed");
4172                 journal_dev = new_decode_dev(journal_devnum);
4173         } else
4174                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4175
4176         really_read_only = bdev_read_only(sb->s_bdev);
4177
4178         /*
4179          * Are we loading a blank journal or performing recovery after a
4180          * crash?  For recovery, we need to check in advance whether we
4181          * can get read-write access to the device.
4182          */
4183         if (ext4_has_feature_journal_needs_recovery(sb)) {
4184                 if (sb->s_flags & MS_RDONLY) {
4185                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4186                                         "required on readonly filesystem");
4187                         if (really_read_only) {
4188                                 ext4_msg(sb, KERN_ERR, "write access "
4189                                         "unavailable, cannot proceed");
4190                                 return -EROFS;
4191                         }
4192                         ext4_msg(sb, KERN_INFO, "write access will "
4193                                "be enabled during recovery");
4194                 }
4195         }
4196
4197         if (journal_inum && journal_dev) {
4198                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4199                        "and inode journals!");
4200                 return -EINVAL;
4201         }
4202
4203         if (journal_inum) {
4204                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4205                         return -EINVAL;
4206         } else {
4207                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4208                         return -EINVAL;
4209         }
4210
4211         if (!(journal->j_flags & JBD2_BARRIER))
4212                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4213
4214         if (!ext4_has_feature_journal_needs_recovery(sb))
4215                 err = jbd2_journal_wipe(journal, !really_read_only);
4216         if (!err) {
4217                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4218                 if (save)
4219                         memcpy(save, ((char *) es) +
4220                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4221                 err = jbd2_journal_load(journal);
4222                 if (save)
4223                         memcpy(((char *) es) + EXT4_S_ERR_START,
4224                                save, EXT4_S_ERR_LEN);
4225                 kfree(save);
4226         }
4227
4228         if (err) {
4229                 ext4_msg(sb, KERN_ERR, "error loading journal");
4230                 jbd2_journal_destroy(journal);
4231                 return err;
4232         }
4233
4234         EXT4_SB(sb)->s_journal = journal;
4235         ext4_clear_journal_err(sb, es);
4236
4237         if (!really_read_only && journal_devnum &&
4238             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4239                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4240
4241                 /* Make sure we flush the recovery flag to disk. */
4242                 ext4_commit_super(sb, 1);
4243         }
4244
4245         return 0;
4246 }
4247
4248 static int ext4_commit_super(struct super_block *sb, int sync)
4249 {
4250         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4251         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4252         int error = 0;
4253
4254         if (!sbh || block_device_ejected(sb))
4255                 return error;
4256         if (buffer_write_io_error(sbh)) {
4257                 /*
4258                  * Oh, dear.  A previous attempt to write the
4259                  * superblock failed.  This could happen because the
4260                  * USB device was yanked out.  Or it could happen to
4261                  * be a transient write error and maybe the block will
4262                  * be remapped.  Nothing we can do but to retry the
4263                  * write and hope for the best.
4264                  */
4265                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4266                        "superblock detected");
4267                 clear_buffer_write_io_error(sbh);
4268                 set_buffer_uptodate(sbh);
4269         }
4270         /*
4271          * If the file system is mounted read-only, don't update the
4272          * superblock write time.  This avoids updating the superblock
4273          * write time when we are mounting the root file system
4274          * read/only but we need to replay the journal; at that point,
4275          * for people who are east of GMT and who make their clock
4276          * tick in localtime for Windows bug-for-bug compatibility,
4277          * the clock is set in the future, and this will cause e2fsck
4278          * to complain and force a full file system check.
4279          */
4280         if (!(sb->s_flags & MS_RDONLY))
4281                 es->s_wtime = cpu_to_le32(get_seconds());
4282         if (sb->s_bdev->bd_part)
4283                 es->s_kbytes_written =
4284                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4285                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4286                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4287         else
4288                 es->s_kbytes_written =
4289                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4290         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
4291                 ext4_free_blocks_count_set(es,
4292                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4293                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4294         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
4295                 es->s_free_inodes_count =
4296                         cpu_to_le32(percpu_counter_sum_positive(
4297                                 &EXT4_SB(sb)->s_freeinodes_counter));
4298         BUFFER_TRACE(sbh, "marking dirty");
4299         ext4_superblock_csum_set(sb);
4300         mark_buffer_dirty(sbh);
4301         if (sync) {
4302                 error = __sync_dirty_buffer(sbh,
4303                         test_opt(sb, BARRIER) ? WRITE_FUA : WRITE_SYNC);
4304                 if (error)
4305                         return error;
4306
4307                 error = buffer_write_io_error(sbh);
4308                 if (error) {
4309                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4310                                "superblock");
4311                         clear_buffer_write_io_error(sbh);
4312                         set_buffer_uptodate(sbh);
4313                 }
4314         }
4315         return error;
4316 }
4317
4318 /*
4319  * Have we just finished recovery?  If so, and if we are mounting (or
4320  * remounting) the filesystem readonly, then we will end up with a
4321  * consistent fs on disk.  Record that fact.
4322  */
4323 static void ext4_mark_recovery_complete(struct super_block *sb,
4324                                         struct ext4_super_block *es)
4325 {
4326         journal_t *journal = EXT4_SB(sb)->s_journal;
4327
4328         if (!ext4_has_feature_journal(sb)) {
4329                 BUG_ON(journal != NULL);
4330                 return;
4331         }
4332         jbd2_journal_lock_updates(journal);
4333         if (jbd2_journal_flush(journal) < 0)
4334                 goto out;
4335
4336         if (ext4_has_feature_journal_needs_recovery(sb) &&
4337             sb->s_flags & MS_RDONLY) {
4338                 ext4_clear_feature_journal_needs_recovery(sb);
4339                 ext4_commit_super(sb, 1);
4340         }
4341
4342 out:
4343         jbd2_journal_unlock_updates(journal);
4344 }
4345
4346 /*
4347  * If we are mounting (or read-write remounting) a filesystem whose journal
4348  * has recorded an error from a previous lifetime, move that error to the
4349  * main filesystem now.
4350  */
4351 static void ext4_clear_journal_err(struct super_block *sb,
4352                                    struct ext4_super_block *es)
4353 {
4354         journal_t *journal;
4355         int j_errno;
4356         const char *errstr;
4357
4358         BUG_ON(!ext4_has_feature_journal(sb));
4359
4360         journal = EXT4_SB(sb)->s_journal;
4361
4362         /*
4363          * Now check for any error status which may have been recorded in the
4364          * journal by a prior ext4_error() or ext4_abort()
4365          */
4366
4367         j_errno = jbd2_journal_errno(journal);
4368         if (j_errno) {
4369                 char nbuf[16];
4370
4371                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4372                 ext4_warning(sb, "Filesystem error recorded "
4373                              "from previous mount: %s", errstr);
4374                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4375
4376                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4377                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4378                 ext4_commit_super(sb, 1);
4379
4380                 jbd2_journal_clear_err(journal);
4381                 jbd2_journal_update_sb_errno(journal);
4382         }
4383 }
4384
4385 /*
4386  * Force the running and committing transactions to commit,
4387  * and wait on the commit.
4388  */
4389 int ext4_force_commit(struct super_block *sb)
4390 {
4391         journal_t *journal;
4392
4393         if (sb->s_flags & MS_RDONLY)
4394                 return 0;
4395
4396         journal = EXT4_SB(sb)->s_journal;
4397         return ext4_journal_force_commit(journal);
4398 }
4399
4400 static int ext4_sync_fs(struct super_block *sb, int wait)
4401 {
4402         int ret = 0;
4403         tid_t target;
4404         bool needs_barrier = false;
4405         struct ext4_sb_info *sbi = EXT4_SB(sb);
4406
4407         trace_ext4_sync_fs(sb, wait);
4408         flush_workqueue(sbi->rsv_conversion_wq);
4409         /*
4410          * Writeback quota in non-journalled quota case - journalled quota has
4411          * no dirty dquots
4412          */
4413         dquot_writeback_dquots(sb, -1);
4414         /*
4415          * Data writeback is possible w/o journal transaction, so barrier must
4416          * being sent at the end of the function. But we can skip it if
4417          * transaction_commit will do it for us.
4418          */
4419         if (sbi->s_journal) {
4420                 target = jbd2_get_latest_transaction(sbi->s_journal);
4421                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
4422                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
4423                         needs_barrier = true;
4424
4425                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4426                         if (wait)
4427                                 ret = jbd2_log_wait_commit(sbi->s_journal,
4428                                                            target);
4429                 }
4430         } else if (wait && test_opt(sb, BARRIER))
4431                 needs_barrier = true;
4432         if (needs_barrier) {
4433                 int err;
4434                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
4435                 if (!ret)
4436                         ret = err;
4437         }
4438
4439         return ret;
4440 }
4441
4442 /*
4443  * LVM calls this function before a (read-only) snapshot is created.  This
4444  * gives us a chance to flush the journal completely and mark the fs clean.
4445  *
4446  * Note that only this function cannot bring a filesystem to be in a clean
4447  * state independently. It relies on upper layer to stop all data & metadata
4448  * modifications.
4449  */
4450 static int ext4_freeze(struct super_block *sb)
4451 {
4452         int error = 0;
4453         journal_t *journal;
4454
4455         if (sb->s_flags & MS_RDONLY)
4456                 return 0;
4457
4458         journal = EXT4_SB(sb)->s_journal;
4459
4460         if (journal) {
4461                 /* Now we set up the journal barrier. */
4462                 jbd2_journal_lock_updates(journal);
4463
4464                 /*
4465                  * Don't clear the needs_recovery flag if we failed to
4466                  * flush the journal.
4467                  */
4468                 error = jbd2_journal_flush(journal);
4469                 if (error < 0)
4470                         goto out;
4471
4472                 /* Journal blocked and flushed, clear needs_recovery flag. */
4473                 ext4_clear_feature_journal_needs_recovery(sb);
4474         }
4475
4476         error = ext4_commit_super(sb, 1);
4477 out:
4478         if (journal)
4479                 /* we rely on upper layer to stop further updates */
4480                 jbd2_journal_unlock_updates(journal);
4481         return error;
4482 }
4483
4484 /*
4485  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4486  * flag here, even though the filesystem is not technically dirty yet.
4487  */
4488 static int ext4_unfreeze(struct super_block *sb)
4489 {
4490         if (sb->s_flags & MS_RDONLY)
4491                 return 0;
4492
4493         if (EXT4_SB(sb)->s_journal) {
4494                 /* Reset the needs_recovery flag before the fs is unlocked. */
4495                 ext4_set_feature_journal_needs_recovery(sb);
4496         }
4497
4498         ext4_commit_super(sb, 1);
4499         return 0;
4500 }
4501
4502 /*
4503  * Structure to save mount options for ext4_remount's benefit
4504  */
4505 struct ext4_mount_options {
4506         unsigned long s_mount_opt;
4507         unsigned long s_mount_opt2;
4508         kuid_t s_resuid;
4509         kgid_t s_resgid;
4510         unsigned long s_commit_interval;
4511         u32 s_min_batch_time, s_max_batch_time;
4512 #ifdef CONFIG_QUOTA
4513         int s_jquota_fmt;
4514         char *s_qf_names[EXT4_MAXQUOTAS];
4515 #endif
4516 };
4517
4518 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4519 {
4520         struct ext4_super_block *es;
4521         struct ext4_sb_info *sbi = EXT4_SB(sb);
4522         unsigned long old_sb_flags;
4523         struct ext4_mount_options old_opts;
4524         int enable_quota = 0;
4525         ext4_group_t g;
4526         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4527         int err = 0;
4528 #ifdef CONFIG_QUOTA
4529         int i, j;
4530 #endif
4531         char *orig_data = kstrdup(data, GFP_KERNEL);
4532
4533         /* Store the original options */
4534         old_sb_flags = sb->s_flags;
4535         old_opts.s_mount_opt = sbi->s_mount_opt;
4536         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4537         old_opts.s_resuid = sbi->s_resuid;
4538         old_opts.s_resgid = sbi->s_resgid;
4539         old_opts.s_commit_interval = sbi->s_commit_interval;
4540         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4541         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4542 #ifdef CONFIG_QUOTA
4543         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4544         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4545                 if (sbi->s_qf_names[i]) {
4546                         old_opts.s_qf_names[i] = kstrdup(sbi->s_qf_names[i],
4547                                                          GFP_KERNEL);
4548                         if (!old_opts.s_qf_names[i]) {
4549                                 for (j = 0; j < i; j++)
4550                                         kfree(old_opts.s_qf_names[j]);
4551                                 kfree(orig_data);
4552                                 return -ENOMEM;
4553                         }
4554                 } else
4555                         old_opts.s_qf_names[i] = NULL;
4556 #endif
4557         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4558                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4559
4560         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
4561                 err = -EINVAL;
4562                 goto restore_opts;
4563         }
4564
4565         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
4566             test_opt(sb, JOURNAL_CHECKSUM)) {
4567                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
4568                          "during remount not supported; ignoring");
4569                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
4570         }
4571
4572         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4573                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4574                         ext4_msg(sb, KERN_ERR, "can't mount with "
4575                                  "both data=journal and delalloc");
4576                         err = -EINVAL;
4577                         goto restore_opts;
4578                 }
4579                 if (test_opt(sb, DIOREAD_NOLOCK)) {
4580                         ext4_msg(sb, KERN_ERR, "can't mount with "
4581                                  "both data=journal and dioread_nolock");
4582                         err = -EINVAL;
4583                         goto restore_opts;
4584                 }
4585                 if (test_opt(sb, DAX)) {
4586                         ext4_msg(sb, KERN_ERR, "can't mount with "
4587                                  "both data=journal and dax");
4588                         err = -EINVAL;
4589                         goto restore_opts;
4590                 }
4591         }
4592
4593         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
4594                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
4595                         "dax flag with busy inodes while remounting");
4596                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
4597         }
4598
4599         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4600                 ext4_abort(sb, "Abort forced by user");
4601
4602         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
4603                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
4604
4605         es = sbi->s_es;
4606
4607         if (sbi->s_journal) {
4608                 ext4_init_journal_params(sb, sbi->s_journal);
4609                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4610         }
4611
4612         if (*flags & MS_LAZYTIME)
4613                 sb->s_flags |= MS_LAZYTIME;
4614
4615         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY)) {
4616                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
4617                         err = -EROFS;
4618                         goto restore_opts;
4619                 }
4620
4621                 if (*flags & MS_RDONLY) {
4622                         err = sync_filesystem(sb);
4623                         if (err < 0)
4624                                 goto restore_opts;
4625                         err = dquot_suspend(sb, -1);
4626                         if (err < 0)
4627                                 goto restore_opts;
4628
4629                         /*
4630                          * First of all, the unconditional stuff we have to do
4631                          * to disable replay of the journal when we next remount
4632                          */
4633                         sb->s_flags |= MS_RDONLY;
4634
4635                         /*
4636                          * OK, test if we are remounting a valid rw partition
4637                          * readonly, and if so set the rdonly flag and then
4638                          * mark the partition as valid again.
4639                          */
4640                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
4641                             (sbi->s_mount_state & EXT4_VALID_FS))
4642                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
4643
4644                         if (sbi->s_journal)
4645                                 ext4_mark_recovery_complete(sb, es);
4646                 } else {
4647                         /* Make sure we can mount this feature set readwrite */
4648                         if (ext4_has_feature_readonly(sb) ||
4649                             !ext4_feature_set_ok(sb, 0)) {
4650                                 err = -EROFS;
4651                                 goto restore_opts;
4652                         }
4653                         /*
4654                          * Make sure the group descriptor checksums
4655                          * are sane.  If they aren't, refuse to remount r/w.
4656                          */
4657                         for (g = 0; g < sbi->s_groups_count; g++) {
4658                                 struct ext4_group_desc *gdp =
4659                                         ext4_get_group_desc(sb, g, NULL);
4660
4661                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
4662                                         ext4_msg(sb, KERN_ERR,
4663                "ext4_remount: Checksum for group %u failed (%u!=%u)",
4664                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
4665                                                le16_to_cpu(gdp->bg_checksum));
4666                                         err = -EFSBADCRC;
4667                                         goto restore_opts;
4668                                 }
4669                         }
4670
4671                         /*
4672                          * If we have an unprocessed orphan list hanging
4673                          * around from a previously readonly bdev mount,
4674                          * require a full umount/remount for now.
4675                          */
4676                         if (es->s_last_orphan) {
4677                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
4678                                        "remount RDWR because of unprocessed "
4679                                        "orphan inode list.  Please "
4680                                        "umount/remount instead");
4681                                 err = -EINVAL;
4682                                 goto restore_opts;
4683                         }
4684
4685                         /*
4686                          * Mounting a RDONLY partition read-write, so reread
4687                          * and store the current valid flag.  (It may have
4688                          * been changed by e2fsck since we originally mounted
4689                          * the partition.)
4690                          */
4691                         if (sbi->s_journal)
4692                                 ext4_clear_journal_err(sb, es);
4693                         sbi->s_mount_state = le16_to_cpu(es->s_state);
4694                         if (!ext4_setup_super(sb, es, 0))
4695                                 sb->s_flags &= ~MS_RDONLY;
4696                         if (ext4_has_feature_mmp(sb))
4697                                 if (ext4_multi_mount_protect(sb,
4698                                                 le64_to_cpu(es->s_mmp_block))) {
4699                                         err = -EROFS;
4700                                         goto restore_opts;
4701                                 }
4702                         enable_quota = 1;
4703                 }
4704         }
4705
4706         /*
4707          * Reinitialize lazy itable initialization thread based on
4708          * current settings
4709          */
4710         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
4711                 ext4_unregister_li_request(sb);
4712         else {
4713                 ext4_group_t first_not_zeroed;
4714                 first_not_zeroed = ext4_has_uninit_itable(sb);
4715                 ext4_register_li_request(sb, first_not_zeroed);
4716         }
4717
4718         ext4_setup_system_zone(sb);
4719         if (sbi->s_journal == NULL && !(old_sb_flags & MS_RDONLY))
4720                 ext4_commit_super(sb, 1);
4721
4722 #ifdef CONFIG_QUOTA
4723         /* Release old quota file names */
4724         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4725                 kfree(old_opts.s_qf_names[i]);
4726         if (enable_quota) {
4727                 if (sb_any_quota_suspended(sb))
4728                         dquot_resume(sb, -1);
4729                 else if (ext4_has_feature_quota(sb)) {
4730                         err = ext4_enable_quotas(sb);
4731                         if (err)
4732                                 goto restore_opts;
4733                 }
4734         }
4735 #endif
4736
4737         *flags = (*flags & ~MS_LAZYTIME) | (sb->s_flags & MS_LAZYTIME);
4738         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
4739         kfree(orig_data);
4740         return 0;
4741
4742 restore_opts:
4743         sb->s_flags = old_sb_flags;
4744         sbi->s_mount_opt = old_opts.s_mount_opt;
4745         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
4746         sbi->s_resuid = old_opts.s_resuid;
4747         sbi->s_resgid = old_opts.s_resgid;
4748         sbi->s_commit_interval = old_opts.s_commit_interval;
4749         sbi->s_min_batch_time = old_opts.s_min_batch_time;
4750         sbi->s_max_batch_time = old_opts.s_max_batch_time;
4751 #ifdef CONFIG_QUOTA
4752         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
4753         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
4754                 kfree(sbi->s_qf_names[i]);
4755                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
4756         }
4757 #endif
4758         kfree(orig_data);
4759         return err;
4760 }
4761
4762 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
4763 {
4764         struct super_block *sb = dentry->d_sb;
4765         struct ext4_sb_info *sbi = EXT4_SB(sb);
4766         struct ext4_super_block *es = sbi->s_es;
4767         ext4_fsblk_t overhead = 0, resv_blocks;
4768         u64 fsid;
4769         s64 bfree;
4770         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
4771
4772         if (!test_opt(sb, MINIX_DF))
4773                 overhead = sbi->s_overhead;
4774
4775         buf->f_type = EXT4_SUPER_MAGIC;
4776         buf->f_bsize = sb->s_blocksize;
4777         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
4778         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
4779                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
4780         /* prevent underflow in case that few free space is available */
4781         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
4782         buf->f_bavail = buf->f_bfree -
4783                         (ext4_r_blocks_count(es) + resv_blocks);
4784         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
4785                 buf->f_bavail = 0;
4786         buf->f_files = le32_to_cpu(es->s_inodes_count);
4787         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
4788         buf->f_namelen = EXT4_NAME_LEN;
4789         fsid = le64_to_cpup((void *)es->s_uuid) ^
4790                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
4791         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
4792         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
4793
4794         return 0;
4795 }
4796
4797 /* Helper function for writing quotas on sync - we need to start transaction
4798  * before quota file is locked for write. Otherwise the are possible deadlocks:
4799  * Process 1                         Process 2
4800  * ext4_create()                     quota_sync()
4801  *   jbd2_journal_start()                  write_dquot()
4802  *   dquot_initialize()                         down(dqio_mutex)
4803  *     down(dqio_mutex)                    jbd2_journal_start()
4804  *
4805  */
4806
4807 #ifdef CONFIG_QUOTA
4808
4809 static inline struct inode *dquot_to_inode(struct dquot *dquot)
4810 {
4811         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
4812 }
4813
4814 static int ext4_write_dquot(struct dquot *dquot)
4815 {
4816         int ret, err;
4817         handle_t *handle;
4818         struct inode *inode;
4819
4820         inode = dquot_to_inode(dquot);
4821         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
4822                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
4823         if (IS_ERR(handle))
4824                 return PTR_ERR(handle);
4825         ret = dquot_commit(dquot);
4826         err = ext4_journal_stop(handle);
4827         if (!ret)
4828                 ret = err;
4829         return ret;
4830 }
4831
4832 static int ext4_acquire_dquot(struct dquot *dquot)
4833 {
4834         int ret, err;
4835         handle_t *handle;
4836
4837         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
4838                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
4839         if (IS_ERR(handle))
4840                 return PTR_ERR(handle);
4841         ret = dquot_acquire(dquot);
4842         err = ext4_journal_stop(handle);
4843         if (!ret)
4844                 ret = err;
4845         return ret;
4846 }
4847
4848 static int ext4_release_dquot(struct dquot *dquot)
4849 {
4850         int ret, err;
4851         handle_t *handle;
4852
4853         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
4854                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
4855         if (IS_ERR(handle)) {
4856                 /* Release dquot anyway to avoid endless cycle in dqput() */
4857                 dquot_release(dquot);
4858                 return PTR_ERR(handle);
4859         }
4860         ret = dquot_release(dquot);
4861         err = ext4_journal_stop(handle);
4862         if (!ret)
4863                 ret = err;
4864         return ret;
4865 }
4866
4867 static int ext4_mark_dquot_dirty(struct dquot *dquot)
4868 {
4869         struct super_block *sb = dquot->dq_sb;
4870         struct ext4_sb_info *sbi = EXT4_SB(sb);
4871
4872         /* Are we journaling quotas? */
4873         if (ext4_has_feature_quota(sb) ||
4874             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
4875                 dquot_mark_dquot_dirty(dquot);
4876                 return ext4_write_dquot(dquot);
4877         } else {
4878                 return dquot_mark_dquot_dirty(dquot);
4879         }
4880 }
4881
4882 static int ext4_write_info(struct super_block *sb, int type)
4883 {
4884         int ret, err;
4885         handle_t *handle;
4886
4887         /* Data block + inode block */
4888         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
4889         if (IS_ERR(handle))
4890                 return PTR_ERR(handle);
4891         ret = dquot_commit_info(sb, type);
4892         err = ext4_journal_stop(handle);
4893         if (!ret)
4894                 ret = err;
4895         return ret;
4896 }
4897
4898 /*
4899  * Turn on quotas during mount time - we need to find
4900  * the quota file and such...
4901  */
4902 static int ext4_quota_on_mount(struct super_block *sb, int type)
4903 {
4904         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
4905                                         EXT4_SB(sb)->s_jquota_fmt, type);
4906 }
4907
4908 /*
4909  * Standard function to be called on quota_on
4910  */
4911 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
4912                          struct path *path)
4913 {
4914         int err;
4915
4916         if (!test_opt(sb, QUOTA))
4917                 return -EINVAL;
4918
4919         /* Quotafile not on the same filesystem? */
4920         if (path->dentry->d_sb != sb)
4921                 return -EXDEV;
4922         /* Journaling quota? */
4923         if (EXT4_SB(sb)->s_qf_names[type]) {
4924                 /* Quotafile not in fs root? */
4925                 if (path->dentry->d_parent != sb->s_root)
4926                         ext4_msg(sb, KERN_WARNING,
4927                                 "Quota file not on filesystem root. "
4928                                 "Journaled quota will not work");
4929         }
4930
4931         /*
4932          * When we journal data on quota file, we have to flush journal to see
4933          * all updates to the file when we bypass pagecache...
4934          */
4935         if (EXT4_SB(sb)->s_journal &&
4936             ext4_should_journal_data(d_inode(path->dentry))) {
4937                 /*
4938                  * We don't need to lock updates but journal_flush() could
4939                  * otherwise be livelocked...
4940                  */
4941                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
4942                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
4943                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4944                 if (err)
4945                         return err;
4946         }
4947
4948         return dquot_quota_on(sb, type, format_id, path);
4949 }
4950
4951 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
4952                              unsigned int flags)
4953 {
4954         int err;
4955         struct inode *qf_inode;
4956         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
4957                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
4958                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
4959         };
4960
4961         BUG_ON(!ext4_has_feature_quota(sb));
4962
4963         if (!qf_inums[type])
4964                 return -EPERM;
4965
4966         qf_inode = ext4_iget(sb, qf_inums[type]);
4967         if (IS_ERR(qf_inode)) {
4968                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
4969                 return PTR_ERR(qf_inode);
4970         }
4971
4972         /* Don't account quota for quota files to avoid recursion */
4973         qf_inode->i_flags |= S_NOQUOTA;
4974         err = dquot_enable(qf_inode, type, format_id, flags);
4975         iput(qf_inode);
4976
4977         return err;
4978 }
4979
4980 /* Enable usage tracking for all quota types. */
4981 static int ext4_enable_quotas(struct super_block *sb)
4982 {
4983         int type, err = 0;
4984         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
4985                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
4986                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
4987         };
4988
4989         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
4990         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
4991                 if (qf_inums[type]) {
4992                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
4993                                                 DQUOT_USAGE_ENABLED);
4994                         if (err) {
4995                                 ext4_warning(sb,
4996                                         "Failed to enable quota tracking "
4997                                         "(type=%d, err=%d). Please run "
4998                                         "e2fsck to fix.", type, err);
4999                                 return err;
5000                         }
5001                 }
5002         }
5003         return 0;
5004 }
5005
5006 static int ext4_quota_off(struct super_block *sb, int type)
5007 {
5008         struct inode *inode = sb_dqopt(sb)->files[type];
5009         handle_t *handle;
5010
5011         /* Force all delayed allocation blocks to be allocated.
5012          * Caller already holds s_umount sem */
5013         if (test_opt(sb, DELALLOC))
5014                 sync_filesystem(sb);
5015
5016         if (!inode)
5017                 goto out;
5018
5019         /* Update modification times of quota files when userspace can
5020          * start looking at them */
5021         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5022         if (IS_ERR(handle))
5023                 goto out;
5024         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
5025         ext4_mark_inode_dirty(handle, inode);
5026         ext4_journal_stop(handle);
5027
5028 out:
5029         return dquot_quota_off(sb, type);
5030 }
5031
5032 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5033  * acquiring the locks... As quota files are never truncated and quota code
5034  * itself serializes the operations (and no one else should touch the files)
5035  * we don't have to be afraid of races */
5036 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5037                                size_t len, loff_t off)
5038 {
5039         struct inode *inode = sb_dqopt(sb)->files[type];
5040         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5041         int offset = off & (sb->s_blocksize - 1);
5042         int tocopy;
5043         size_t toread;
5044         struct buffer_head *bh;
5045         loff_t i_size = i_size_read(inode);
5046
5047         if (off > i_size)
5048                 return 0;
5049         if (off+len > i_size)
5050                 len = i_size-off;
5051         toread = len;
5052         while (toread > 0) {
5053                 tocopy = sb->s_blocksize - offset < toread ?
5054                                 sb->s_blocksize - offset : toread;
5055                 bh = ext4_bread(NULL, inode, blk, 0);
5056                 if (IS_ERR(bh))
5057                         return PTR_ERR(bh);
5058                 if (!bh)        /* A hole? */
5059                         memset(data, 0, tocopy);
5060                 else
5061                         memcpy(data, bh->b_data+offset, tocopy);
5062                 brelse(bh);
5063                 offset = 0;
5064                 toread -= tocopy;
5065                 data += tocopy;
5066                 blk++;
5067         }
5068         return len;
5069 }
5070
5071 /* Write to quotafile (we know the transaction is already started and has
5072  * enough credits) */
5073 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5074                                 const char *data, size_t len, loff_t off)
5075 {
5076         struct inode *inode = sb_dqopt(sb)->files[type];
5077         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5078         int err, offset = off & (sb->s_blocksize - 1);
5079         int retries = 0;
5080         struct buffer_head *bh;
5081         handle_t *handle = journal_current_handle();
5082
5083         if (EXT4_SB(sb)->s_journal && !handle) {
5084                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5085                         " cancelled because transaction is not started",
5086                         (unsigned long long)off, (unsigned long long)len);
5087                 return -EIO;
5088         }
5089         /*
5090          * Since we account only one data block in transaction credits,
5091          * then it is impossible to cross a block boundary.
5092          */
5093         if (sb->s_blocksize - offset < len) {
5094                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5095                         " cancelled because not block aligned",
5096                         (unsigned long long)off, (unsigned long long)len);
5097                 return -EIO;
5098         }
5099
5100         do {
5101                 bh = ext4_bread(handle, inode, blk,
5102                                 EXT4_GET_BLOCKS_CREATE |
5103                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
5104         } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
5105                  ext4_should_retry_alloc(inode->i_sb, &retries));
5106         if (IS_ERR(bh))
5107                 return PTR_ERR(bh);
5108         if (!bh)
5109                 goto out;
5110         BUFFER_TRACE(bh, "get write access");
5111         err = ext4_journal_get_write_access(handle, bh);
5112         if (err) {
5113                 brelse(bh);
5114                 return err;
5115         }
5116         lock_buffer(bh);
5117         memcpy(bh->b_data+offset, data, len);
5118         flush_dcache_page(bh->b_page);
5119         unlock_buffer(bh);
5120         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5121         brelse(bh);
5122 out:
5123         if (inode->i_size < off + len) {
5124                 i_size_write(inode, off + len);
5125                 EXT4_I(inode)->i_disksize = inode->i_size;
5126                 ext4_mark_inode_dirty(handle, inode);
5127         }
5128         return len;
5129 }
5130
5131 #endif
5132
5133 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5134                        const char *dev_name, void *data)
5135 {
5136         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5137 }
5138
5139 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
5140 static inline void register_as_ext2(void)
5141 {
5142         int err = register_filesystem(&ext2_fs_type);
5143         if (err)
5144                 printk(KERN_WARNING
5145                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5146 }
5147
5148 static inline void unregister_as_ext2(void)
5149 {
5150         unregister_filesystem(&ext2_fs_type);
5151 }
5152
5153 static inline int ext2_feature_set_ok(struct super_block *sb)
5154 {
5155         if (ext4_has_unknown_ext2_incompat_features(sb))
5156                 return 0;
5157         if (sb->s_flags & MS_RDONLY)
5158                 return 1;
5159         if (ext4_has_unknown_ext2_ro_compat_features(sb))
5160                 return 0;
5161         return 1;
5162 }
5163 #else
5164 static inline void register_as_ext2(void) { }
5165 static inline void unregister_as_ext2(void) { }
5166 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5167 #endif
5168
5169 static inline void register_as_ext3(void)
5170 {
5171         int err = register_filesystem(&ext3_fs_type);
5172         if (err)
5173                 printk(KERN_WARNING
5174                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5175 }
5176
5177 static inline void unregister_as_ext3(void)
5178 {
5179         unregister_filesystem(&ext3_fs_type);
5180 }
5181
5182 static inline int ext3_feature_set_ok(struct super_block *sb)
5183 {
5184         if (ext4_has_unknown_ext3_incompat_features(sb))
5185                 return 0;
5186         if (!ext4_has_feature_journal(sb))
5187                 return 0;
5188         if (sb->s_flags & MS_RDONLY)
5189                 return 1;
5190         if (ext4_has_unknown_ext3_ro_compat_features(sb))
5191                 return 0;
5192         return 1;
5193 }
5194
5195 static struct file_system_type ext4_fs_type = {
5196         .owner          = THIS_MODULE,
5197         .name           = "ext4",
5198         .mount          = ext4_mount,
5199         .kill_sb        = kill_block_super,
5200         .fs_flags       = FS_REQUIRES_DEV,
5201 };
5202 MODULE_ALIAS_FS("ext4");
5203
5204 /* Shared across all ext4 file systems */
5205 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5206 struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
5207
5208 static int __init ext4_init_fs(void)
5209 {
5210         int i, err;
5211
5212         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
5213         ext4_li_info = NULL;
5214         mutex_init(&ext4_li_mtx);
5215
5216         /* Build-time check for flags consistency */
5217         ext4_check_flag_values();
5218
5219         for (i = 0; i < EXT4_WQ_HASH_SZ; i++) {
5220                 mutex_init(&ext4__aio_mutex[i]);
5221                 init_waitqueue_head(&ext4__ioend_wq[i]);
5222         }
5223
5224         err = ext4_init_es();
5225         if (err)
5226                 return err;
5227
5228         err = ext4_init_pageio();
5229         if (err)
5230                 goto out5;
5231
5232         err = ext4_init_system_zone();
5233         if (err)
5234                 goto out4;
5235
5236         err = ext4_init_sysfs();
5237         if (err)
5238                 goto out3;
5239
5240         err = ext4_init_mballoc();
5241         if (err)
5242                 goto out2;
5243         else
5244                 ext4_mballoc_ready = 1;
5245         err = init_inodecache();
5246         if (err)
5247                 goto out1;
5248         register_as_ext3();
5249         register_as_ext2();
5250         err = register_filesystem(&ext4_fs_type);
5251         if (err)
5252                 goto out;
5253
5254         return 0;
5255 out:
5256         unregister_as_ext2();
5257         unregister_as_ext3();
5258         destroy_inodecache();
5259 out1:
5260         ext4_mballoc_ready = 0;
5261         ext4_exit_mballoc();
5262 out2:
5263         ext4_exit_sysfs();
5264 out3:
5265         ext4_exit_system_zone();
5266 out4:
5267         ext4_exit_pageio();
5268 out5:
5269         ext4_exit_es();
5270
5271         return err;
5272 }
5273
5274 static void __exit ext4_exit_fs(void)
5275 {
5276         ext4_exit_crypto();
5277         ext4_destroy_lazyinit_thread();
5278         unregister_as_ext2();
5279         unregister_as_ext3();
5280         unregister_filesystem(&ext4_fs_type);
5281         destroy_inodecache();
5282         ext4_exit_mballoc();
5283         ext4_exit_sysfs();
5284         ext4_exit_system_zone();
5285         ext4_exit_pageio();
5286         ext4_exit_es();
5287 }
5288
5289 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5290 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5291 MODULE_LICENSE("GPL");
5292 module_init(ext4_init_fs)
5293 module_exit(ext4_exit_fs)