Pileus Git - ~andy/linux/blob - 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/jbd2.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.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/proc_fs.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/cleancache.h>
  42 #include <asm/uaccess.h>
  43
  44 #include <linux/kthread.h>
  45 #include <linux/freezer.h>
  46
  47 #include "ext4.h"
  48 #include "ext4_extents.h"       /* Needed for trace points definition */
  49 #include "ext4_jbd2.h"
  50 #include "xattr.h"
  51 #include "acl.h"
  52 #include "mballoc.h"
  53
  54 #define CREATE_TRACE_POINTS
  55 #include <trace/events/ext4.h>
  56
  57 static struct proc_dir_entry *ext4_proc_root;
  58 static struct kset *ext4_kset;
  59 static struct ext4_lazy_init *ext4_li_info;
  60 static struct mutex ext4_li_mtx;
  61 static struct ext4_features *ext4_feat;
  62
  63 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  64                              unsigned long journal_devnum);
  65 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  66 static int ext4_commit_super(struct super_block *sb, int sync);
  67 static void ext4_mark_recovery_complete(struct super_block *sb,
  68                                         struct ext4_super_block *es);
  69 static void ext4_clear_journal_err(struct super_block *sb,
  70                                    struct ext4_super_block *es);
  71 static int ext4_sync_fs(struct super_block *sb, int wait);
  72 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  73 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  74 static int ext4_unfreeze(struct super_block *sb);
  75 static int ext4_freeze(struct super_block *sb);
  76 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  77                        const char *dev_name, void *data);
  78 static inline int ext2_feature_set_ok(struct super_block *sb);
  79 static inline int ext3_feature_set_ok(struct super_block *sb);
  80 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  81 static void ext4_destroy_lazyinit_thread(void);
  82 static void ext4_unregister_li_request(struct super_block *sb);
  83 static void ext4_clear_request_list(void);
  84
  85 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
  86 static struct file_system_type ext2_fs_type = {
  87         .owner          = THIS_MODULE,
  88         .name           = "ext2",
  89         .mount          = ext4_mount,
  90         .kill_sb        = kill_block_super,
  91         .fs_flags       = FS_REQUIRES_DEV,
  92 };
  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 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
 100 static struct file_system_type ext3_fs_type = {
 101         .owner          = THIS_MODULE,
 102         .name           = "ext3",
 103         .mount          = ext4_mount,
 104         .kill_sb        = kill_block_super,
 105         .fs_flags       = FS_REQUIRES_DEV,
 106 };
 107 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 108 #else
 109 #define IS_EXT3_SB(sb) (0)
 110 #endif
 111
 112 static int ext4_verify_csum_type(struct super_block *sb,
 113                                  struct ext4_super_block *es)
 114 {
 115         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 116                                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 117                 return 1;
 118
 119         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 120 }
 121
 122 static __le32 ext4_superblock_csum(struct super_block *sb,
 123                                    struct ext4_super_block *es)
 124 {
 125         struct ext4_sb_info *sbi = EXT4_SB(sb);
 126         int offset = offsetof(struct ext4_super_block, s_checksum);
 127         __u32 csum;
 128
 129         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 130
 131         return cpu_to_le32(csum);
 132 }
 133
 134 int ext4_superblock_csum_verify(struct super_block *sb,
 135                                 struct ext4_super_block *es)
 136 {
 137         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 138                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 139                 return 1;
 140
 141         return es->s_checksum == ext4_superblock_csum(sb, es);
 142 }
 143
 144 void ext4_superblock_csum_set(struct super_block *sb)
 145 {
 146         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 147
 148         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 149                 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 150                 return;
 151
 152         es->s_checksum = ext4_superblock_csum(sb, es);
 153 }
 154
 155 void *ext4_kvmalloc(size_t size, gfp_t flags)
 156 {
 157         void *ret;
 158
 159         ret = kmalloc(size, flags);
 160         if (!ret)
 161                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 162         return ret;
 163 }
 164
 165 void *ext4_kvzalloc(size_t size, gfp_t flags)
 166 {
 167         void *ret;
 168
 169         ret = kzalloc(size, flags);
 170         if (!ret)
 171                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 172         return ret;
 173 }
 174
 175 void ext4_kvfree(void *ptr)
 176 {
 177         if (is_vmalloc_addr(ptr))
 178                 vfree(ptr);
 179         else
 180                 kfree(ptr);
 181
 182 }
 183
 184 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 185                                struct ext4_group_desc *bg)
 186 {
 187         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 188                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 189                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 190 }
 191
 192 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 193                                struct ext4_group_desc *bg)
 194 {
 195         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 196                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 197                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 198 }
 199
 200 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 201                               struct ext4_group_desc *bg)
 202 {
 203         return le32_to_cpu(bg->bg_inode_table_lo) |
 204                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 205                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 206 }
 207
 208 __u32 ext4_free_group_clusters(struct super_block *sb,
 209                                struct ext4_group_desc *bg)
 210 {
 211         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 212                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 213                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 214 }
 215
 216 __u32 ext4_free_inodes_count(struct super_block *sb,
 217                               struct ext4_group_desc *bg)
 218 {
 219         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 220                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 221                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 222 }
 223
 224 __u32 ext4_used_dirs_count(struct super_block *sb,
 225                               struct ext4_group_desc *bg)
 226 {
 227         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 228                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 229                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 230 }
 231
 232 __u32 ext4_itable_unused_count(struct super_block *sb,
 233                               struct ext4_group_desc *bg)
 234 {
 235         return le16_to_cpu(bg->bg_itable_unused_lo) |
 236                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 237                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 238 }
 239
 240 void ext4_block_bitmap_set(struct super_block *sb,
 241                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 242 {
 243         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 244         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 245                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 246 }
 247
 248 void ext4_inode_bitmap_set(struct super_block *sb,
 249                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 250 {
 251         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 252         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 253                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 254 }
 255
 256 void ext4_inode_table_set(struct super_block *sb,
 257                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 258 {
 259         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 260         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 261                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 262 }
 263
 264 void ext4_free_group_clusters_set(struct super_block *sb,
 265                                   struct ext4_group_desc *bg, __u32 count)
 266 {
 267         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 268         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 269                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 270 }
 271
 272 void ext4_free_inodes_set(struct super_block *sb,
 273                           struct ext4_group_desc *bg, __u32 count)
 274 {
 275         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 276         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 277                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 278 }
 279
 280 void ext4_used_dirs_set(struct super_block *sb,
 281                           struct ext4_group_desc *bg, __u32 count)
 282 {
 283         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 284         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 285                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 286 }
 287
 288 void ext4_itable_unused_set(struct super_block *sb,
 289                           struct ext4_group_desc *bg, __u32 count)
 290 {
 291         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 292         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 293                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 294 }
 295
 296
 297 static void __save_error_info(struct super_block *sb, const char *func,
 298                             unsigned int line)
 299 {
 300         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 301
 302         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 303         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 304         es->s_last_error_time = cpu_to_le32(get_seconds());
 305         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 306         es->s_last_error_line = cpu_to_le32(line);
 307         if (!es->s_first_error_time) {
 308                 es->s_first_error_time = es->s_last_error_time;
 309                 strncpy(es->s_first_error_func, func,
 310                         sizeof(es->s_first_error_func));
 311                 es->s_first_error_line = cpu_to_le32(line);
 312                 es->s_first_error_ino = es->s_last_error_ino;
 313                 es->s_first_error_block = es->s_last_error_block;
 314         }
 315         /*
 316          * Start the daily error reporting function if it hasn't been
 317          * started already
 318          */
 319         if (!es->s_error_count)
 320                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 321         le32_add_cpu(&es->s_error_count, 1);
 322 }
 323
 324 static void save_error_info(struct super_block *sb, const char *func,
 325                             unsigned int line)
 326 {
 327         __save_error_info(sb, func, line);
 328         ext4_commit_super(sb, 1);
 329 }
 330
 331 /*
 332  * The del_gendisk() function uninitializes the disk-specific data
 333  * structures, including the bdi structure, without telling anyone
 334  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 335  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 336  * This is a kludge to prevent these oops until we can put in a proper
 337  * hook in del_gendisk() to inform the VFS and file system layers.
 338  */
 339 static int block_device_ejected(struct super_block *sb)
 340 {
 341         struct inode *bd_inode = sb->s_bdev->bd_inode;
 342         struct backing_dev_info *bdi = bd_inode->i_mapping->backing_dev_info;
 343
 344         return bdi->dev == NULL;
 345 }
 346
 347 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 348 {
 349         struct super_block              *sb = journal->j_private;
 350         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 351         int                             error = is_journal_aborted(journal);
 352         struct ext4_journal_cb_entry    *jce, *tmp;
 353
 354         spin_lock(&sbi->s_md_lock);
 355         list_for_each_entry_safe(jce, tmp, &txn->t_private_list, jce_list) {
 356                 list_del_init(&jce->jce_list);
 357                 spin_unlock(&sbi->s_md_lock);
 358                 jce->jce_func(sb, jce, error);
 359                 spin_lock(&sbi->s_md_lock);
 360         }
 361         spin_unlock(&sbi->s_md_lock);
 362 }
 363
 364 /* Deal with the reporting of failure conditions on a filesystem such as
 365  * inconsistencies detected or read IO failures.
 366  *
 367  * On ext2, we can store the error state of the filesystem in the
 368  * superblock.  That is not possible on ext4, because we may have other
 369  * write ordering constraints on the superblock which prevent us from
 370  * writing it out straight away; and given that the journal is about to
 371  * be aborted, we can't rely on the current, or future, transactions to
 372  * write out the superblock safely.
 373  *
 374  * We'll just use the jbd2_journal_abort() error code to record an error in
 375  * the journal instead.  On recovery, the journal will complain about
 376  * that error until we've noted it down and cleared it.
 377  */
 378
 379 static void ext4_handle_error(struct super_block *sb)
 380 {
 381         if (sb->s_flags & MS_RDONLY)
 382                 return;
 383
 384         if (!test_opt(sb, ERRORS_CONT)) {
 385                 journal_t *journal = EXT4_SB(sb)->s_journal;
 386
 387                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 388                 if (journal)
 389                         jbd2_journal_abort(journal, -EIO);
 390         }
 391         if (test_opt(sb, ERRORS_RO)) {
 392                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 393                 sb->s_flags |= MS_RDONLY;
 394         }
 395         if (test_opt(sb, ERRORS_PANIC))
 396                 panic("EXT4-fs (device %s): panic forced after error\n",
 397                         sb->s_id);
 398 }
 399
 400 void __ext4_error(struct super_block *sb, const char *function,
 401                   unsigned int line, const char *fmt, ...)
 402 {
 403         struct va_format vaf;
 404         va_list args;
 405
 406         va_start(args, fmt);
 407         vaf.fmt = fmt;
 408         vaf.va = &args;
 409         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 410                sb->s_id, function, line, current->comm, &vaf);
 411         va_end(args);
 412         save_error_info(sb, function, line);
 413
 414         ext4_handle_error(sb);
 415 }
 416
 417 void ext4_error_inode(struct inode *inode, const char *function,
 418                       unsigned int line, ext4_fsblk_t block,
 419                       const char *fmt, ...)
 420 {
 421         va_list args;
 422         struct va_format vaf;
 423         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 424
 425         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 426         es->s_last_error_block = cpu_to_le64(block);
 427         save_error_info(inode->i_sb, function, line);
 428         va_start(args, fmt);
 429         vaf.fmt = fmt;
 430         vaf.va = &args;
 431         if (block)
 432                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 433                        "inode #%lu: block %llu: comm %s: %pV\n",
 434                        inode->i_sb->s_id, function, line, inode->i_ino,
 435                        block, current->comm, &vaf);
 436         else
 437                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 438                        "inode #%lu: comm %s: %pV\n",
 439                        inode->i_sb->s_id, function, line, inode->i_ino,
 440                        current->comm, &vaf);
 441         va_end(args);
 442
 443         ext4_handle_error(inode->i_sb);
 444 }
 445
 446 void ext4_error_file(struct file *file, const char *function,
 447                      unsigned int line, ext4_fsblk_t block,
 448                      const char *fmt, ...)
 449 {
 450         va_list args;
 451         struct va_format vaf;
 452         struct ext4_super_block *es;
 453         struct inode *inode = file->f_dentry->d_inode;
 454         char pathname[80], *path;
 455
 456         es = EXT4_SB(inode->i_sb)->s_es;
 457         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 458         save_error_info(inode->i_sb, function, line);
 459         path = d_path(&(file->f_path), pathname, sizeof(pathname));
 460         if (IS_ERR(path))
 461                 path = "(unknown)";
 462         va_start(args, fmt);
 463         vaf.fmt = fmt;
 464         vaf.va = &args;
 465         if (block)
 466                 printk(KERN_CRIT
 467                        "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 468                        "block %llu: comm %s: path %s: %pV\n",
 469                        inode->i_sb->s_id, function, line, inode->i_ino,
 470                        block, current->comm, path, &vaf);
 471         else
 472                 printk(KERN_CRIT
 473                        "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 474                        "comm %s: path %s: %pV\n",
 475                        inode->i_sb->s_id, function, line, inode->i_ino,
 476                        current->comm, path, &vaf);
 477         va_end(args);
 478
 479         ext4_handle_error(inode->i_sb);
 480 }
 481
 482 const char *ext4_decode_error(struct super_block *sb, int errno,
 483                               char nbuf[16])
 484 {
 485         char *errstr = NULL;
 486
 487         switch (errno) {
 488         case -EIO:
 489                 errstr = "IO failure";
 490                 break;
 491         case -ENOMEM:
 492                 errstr = "Out of memory";
 493                 break;
 494         case -EROFS:
 495                 if (!sb || (EXT4_SB(sb)->s_journal &&
 496                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 497                         errstr = "Journal has aborted";
 498                 else
 499                         errstr = "Readonly filesystem";
 500                 break;
 501         default:
 502                 /* If the caller passed in an extra buffer for unknown
 503                  * errors, textualise them now.  Else we just return
 504                  * NULL. */
 505                 if (nbuf) {
 506                         /* Check for truncated error codes... */
 507                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 508                                 errstr = nbuf;
 509                 }
 510                 break;
 511         }
 512
 513         return errstr;
 514 }
 515
 516 /* __ext4_std_error decodes expected errors from journaling functions
 517  * automatically and invokes the appropriate error response.  */
 518
 519 void __ext4_std_error(struct super_block *sb, const char *function,
 520                       unsigned int line, int errno)
 521 {
 522         char nbuf[16];
 523         const char *errstr;
 524
 525         /* Special case: if the error is EROFS, and we're not already
 526          * inside a transaction, then there's really no point in logging
 527          * an error. */
 528         if (errno == -EROFS && journal_current_handle() == NULL &&
 529             (sb->s_flags & MS_RDONLY))
 530                 return;
 531
 532         errstr = ext4_decode_error(sb, errno, nbuf);
 533         printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 534                sb->s_id, function, line, errstr);
 535         save_error_info(sb, function, line);
 536
 537         ext4_handle_error(sb);
 538 }
 539
 540 /*
 541  * ext4_abort is a much stronger failure handler than ext4_error.  The
 542  * abort function may be used to deal with unrecoverable failures such
 543  * as journal IO errors or ENOMEM at a critical moment in log management.
 544  *
 545  * We unconditionally force the filesystem into an ABORT|READONLY state,
 546  * unless the error response on the fs has been set to panic in which
 547  * case we take the easy way out and panic immediately.
 548  */
 549
 550 void __ext4_abort(struct super_block *sb, const char *function,
 551                 unsigned int line, const char *fmt, ...)
 552 {
 553         va_list args;
 554
 555         save_error_info(sb, function, line);
 556         va_start(args, fmt);
 557         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
 558                function, line);
 559         vprintk(fmt, args);
 560         printk("\n");
 561         va_end(args);
 562
 563         if ((sb->s_flags & MS_RDONLY) == 0) {
 564                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 565                 sb->s_flags |= MS_RDONLY;
 566                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 567                 if (EXT4_SB(sb)->s_journal)
 568                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 569                 save_error_info(sb, function, line);
 570         }
 571         if (test_opt(sb, ERRORS_PANIC))
 572                 panic("EXT4-fs panic from previous error\n");
 573 }
 574
 575 void ext4_msg(struct super_block *sb, const char *prefix, const char *fmt, ...)
 576 {
 577         struct va_format vaf;
 578         va_list args;
 579
 580         va_start(args, fmt);
 581         vaf.fmt = fmt;
 582         vaf.va = &args;
 583         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 584         va_end(args);
 585 }
 586
 587 void __ext4_warning(struct super_block *sb, const char *function,
 588                     unsigned int line, const char *fmt, ...)
 589 {
 590         struct va_format vaf;
 591         va_list args;
 592
 593         va_start(args, fmt);
 594         vaf.fmt = fmt;
 595         vaf.va = &args;
 596         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 597                sb->s_id, function, line, &vaf);
 598         va_end(args);
 599 }
 600
 601 void __ext4_grp_locked_error(const char *function, unsigned int line,
 602                              struct super_block *sb, ext4_group_t grp,
 603                              unsigned long ino, ext4_fsblk_t block,
 604                              const char *fmt, ...)
 605 __releases(bitlock)
 606 __acquires(bitlock)
 607 {
 608         struct va_format vaf;
 609         va_list args;
 610         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 611
 612         es->s_last_error_ino = cpu_to_le32(ino);
 613         es->s_last_error_block = cpu_to_le64(block);
 614         __save_error_info(sb, function, line);
 615
 616         va_start(args, fmt);
 617
 618         vaf.fmt = fmt;
 619         vaf.va = &args;
 620         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 621                sb->s_id, function, line, grp);
 622         if (ino)
 623                 printk(KERN_CONT "inode %lu: ", ino);
 624         if (block)
 625                 printk(KERN_CONT "block %llu:", (unsigned long long) block);
 626         printk(KERN_CONT "%pV\n", &vaf);
 627         va_end(args);
 628
 629         if (test_opt(sb, ERRORS_CONT)) {
 630                 ext4_commit_super(sb, 0);
 631                 return;
 632         }
 633
 634         ext4_unlock_group(sb, grp);
 635         ext4_handle_error(sb);
 636         /*
 637          * We only get here in the ERRORS_RO case; relocking the group
 638          * may be dangerous, but nothing bad will happen since the
 639          * filesystem will have already been marked read/only and the
 640          * journal has been aborted.  We return 1 as a hint to callers
 641          * who might what to use the return value from
 642          * ext4_grp_locked_error() to distinguish between the
 643          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 644          * aggressively from the ext4 function in question, with a
 645          * more appropriate error code.
 646          */
 647         ext4_lock_group(sb, grp);
 648         return;
 649 }
 650
 651 void ext4_update_dynamic_rev(struct super_block *sb)
 652 {
 653         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 654
 655         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 656                 return;
 657
 658         ext4_warning(sb,
 659                      "updating to rev %d because of new feature flag, "
 660                      "running e2fsck is recommended",
 661                      EXT4_DYNAMIC_REV);
 662
 663         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 664         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 665         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 666         /* leave es->s_feature_*compat flags alone */
 667         /* es->s_uuid will be set by e2fsck if empty */
 668
 669         /*
 670          * The rest of the superblock fields should be zero, and if not it
 671          * means they are likely already in use, so leave them alone.  We
 672          * can leave it up to e2fsck to clean up any inconsistencies there.
 673          */
 674 }
 675
 676 /*
 677  * Open the external journal device
 678  */
 679 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 680 {
 681         struct block_device *bdev;
 682         char b[BDEVNAME_SIZE];
 683
 684         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 685         if (IS_ERR(bdev))
 686                 goto fail;
 687         return bdev;
 688
 689 fail:
 690         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 691                         __bdevname(dev, b), PTR_ERR(bdev));
 692         return NULL;
 693 }
 694
 695 /*
 696  * Release the journal device
 697  */
 698 static int ext4_blkdev_put(struct block_device *bdev)
 699 {
 700         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 701 }
 702
 703 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 704 {
 705         struct block_device *bdev;
 706         int ret = -ENODEV;
 707
 708         bdev = sbi->journal_bdev;
 709         if (bdev) {
 710                 ret = ext4_blkdev_put(bdev);
 711                 sbi->journal_bdev = NULL;
 712         }
 713         return ret;
 714 }
 715
 716 static inline struct inode *orphan_list_entry(struct list_head *l)
 717 {
 718         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 719 }
 720
 721 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 722 {
 723         struct list_head *l;
 724
 725         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 726                  le32_to_cpu(sbi->s_es->s_last_orphan));
 727
 728         printk(KERN_ERR "sb_info orphan list:\n");
 729         list_for_each(l, &sbi->s_orphan) {
 730                 struct inode *inode = orphan_list_entry(l);
 731                 printk(KERN_ERR "  "
 732                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 733                        inode->i_sb->s_id, inode->i_ino, inode,
 734                        inode->i_mode, inode->i_nlink,
 735                        NEXT_ORPHAN(inode));
 736         }
 737 }
 738
 739 static void ext4_put_super(struct super_block *sb)
 740 {
 741         struct ext4_sb_info *sbi = EXT4_SB(sb);
 742         struct ext4_super_block *es = sbi->s_es;
 743         int i, err;
 744
 745         ext4_unregister_li_request(sb);
 746         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 747
 748         flush_workqueue(sbi->dio_unwritten_wq);
 749         destroy_workqueue(sbi->dio_unwritten_wq);
 750
 751         if (sbi->s_journal) {
 752                 err = jbd2_journal_destroy(sbi->s_journal);
 753                 sbi->s_journal = NULL;
 754                 if (err < 0)
 755                         ext4_abort(sb, "Couldn't clean up the journal");
 756         }
 757
 758         ext4_es_unregister_shrinker(sb);
 759         del_timer(&sbi->s_err_report);
 760         ext4_release_system_zone(sb);
 761         ext4_mb_release(sb);
 762         ext4_ext_release(sb);
 763         ext4_xattr_put_super(sb);
 764
 765         if (!(sb->s_flags & MS_RDONLY)) {
 766                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 767                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 768         }
 769         if (!(sb->s_flags & MS_RDONLY))
 770                 ext4_commit_super(sb, 1);
 771
 772         if (sbi->s_proc) {
 773                 remove_proc_entry("options", sbi->s_proc);
 774                 remove_proc_entry(sb->s_id, ext4_proc_root);
 775         }
 776         kobject_del(&sbi->s_kobj);
 777
 778         for (i = 0; i < sbi->s_gdb_count; i++)
 779                 brelse(sbi->s_group_desc[i]);
 780         ext4_kvfree(sbi->s_group_desc);
 781         ext4_kvfree(sbi->s_flex_groups);
 782         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 783         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 784         percpu_counter_destroy(&sbi->s_dirs_counter);
 785         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 786         percpu_counter_destroy(&sbi->s_extent_cache_cnt);
 787         brelse(sbi->s_sbh);
 788 #ifdef CONFIG_QUOTA
 789         for (i = 0; i < MAXQUOTAS; i++)
 790                 kfree(sbi->s_qf_names[i]);
 791 #endif
 792
 793         /* Debugging code just in case the in-memory inode orphan list
 794          * isn't empty.  The on-disk one can be non-empty if we've
 795          * detected an error and taken the fs readonly, but the
 796          * in-memory list had better be clean by this point. */
 797         if (!list_empty(&sbi->s_orphan))
 798                 dump_orphan_list(sb, sbi);
 799         J_ASSERT(list_empty(&sbi->s_orphan));
 800
 801         invalidate_bdev(sb->s_bdev);
 802         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 803                 /*
 804                  * Invalidate the journal device's buffers.  We don't want them
 805                  * floating about in memory - the physical journal device may
 806                  * hotswapped, and it breaks the `ro-after' testing code.
 807                  */
 808                 sync_blockdev(sbi->journal_bdev);
 809                 invalidate_bdev(sbi->journal_bdev);
 810                 ext4_blkdev_remove(sbi);
 811         }
 812         if (sbi->s_mmp_tsk)
 813                 kthread_stop(sbi->s_mmp_tsk);
 814         sb->s_fs_info = NULL;
 815         /*
 816          * Now that we are completely done shutting down the
 817          * superblock, we need to actually destroy the kobject.
 818          */
 819         kobject_put(&sbi->s_kobj);
 820         wait_for_completion(&sbi->s_kobj_unregister);
 821         if (sbi->s_chksum_driver)
 822                 crypto_free_shash(sbi->s_chksum_driver);
 823         kfree(sbi->s_blockgroup_lock);
 824         kfree(sbi);
 825 }
 826
 827 static struct kmem_cache *ext4_inode_cachep;
 828
 829 /*
 830  * Called inside transaction, so use GFP_NOFS
 831  */
 832 static struct inode *ext4_alloc_inode(struct super_block *sb)
 833 {
 834         struct ext4_inode_info *ei;
 835
 836         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 837         if (!ei)
 838                 return NULL;
 839
 840         ei->vfs_inode.i_version = 1;
 841         INIT_LIST_HEAD(&ei->i_prealloc_list);
 842         spin_lock_init(&ei->i_prealloc_lock);
 843         ext4_es_init_tree(&ei->i_es_tree);
 844         rwlock_init(&ei->i_es_lock);
 845         INIT_LIST_HEAD(&ei->i_es_lru);
 846         ei->i_es_lru_nr = 0;
 847         ei->i_reserved_data_blocks = 0;
 848         ei->i_reserved_meta_blocks = 0;
 849         ei->i_allocated_meta_blocks = 0;
 850         ei->i_da_metadata_calc_len = 0;
 851         ei->i_da_metadata_calc_last_lblock = 0;
 852         spin_lock_init(&(ei->i_block_reservation_lock));
 853 #ifdef CONFIG_QUOTA
 854         ei->i_reserved_quota = 0;
 855 #endif
 856         ei->jinode = NULL;
 857         INIT_LIST_HEAD(&ei->i_completed_io_list);
 858         spin_lock_init(&ei->i_completed_io_lock);
 859         ei->i_sync_tid = 0;
 860         ei->i_datasync_tid = 0;
 861         atomic_set(&ei->i_ioend_count, 0);
 862         atomic_set(&ei->i_unwritten, 0);
 863         INIT_WORK(&ei->i_unwritten_work, ext4_end_io_work);
 864
 865         return &ei->vfs_inode;
 866 }
 867
 868 static int ext4_drop_inode(struct inode *inode)
 869 {
 870         int drop = generic_drop_inode(inode);
 871
 872         trace_ext4_drop_inode(inode, drop);
 873         return drop;
 874 }
 875
 876 static void ext4_i_callback(struct rcu_head *head)
 877 {
 878         struct inode *inode = container_of(head, struct inode, i_rcu);
 879         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 880 }
 881
 882 static void ext4_destroy_inode(struct inode *inode)
 883 {
 884         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 885                 ext4_msg(inode->i_sb, KERN_ERR,
 886                          "Inode %lu (%p): orphan list check failed!",
 887                          inode->i_ino, EXT4_I(inode));
 888                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 889                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 890                                 true);
 891                 dump_stack();
 892         }
 893         call_rcu(&inode->i_rcu, ext4_i_callback);
 894 }
 895
 896 static void init_once(void *foo)
 897 {
 898         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 899
 900         INIT_LIST_HEAD(&ei->i_orphan);
 901         init_rwsem(&ei->xattr_sem);
 902         init_rwsem(&ei->i_data_sem);
 903         inode_init_once(&ei->vfs_inode);
 904 }
 905
 906 static int init_inodecache(void)
 907 {
 908         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 909                                              sizeof(struct ext4_inode_info),
 910                                              0, (SLAB_RECLAIM_ACCOUNT|
 911                                                 SLAB_MEM_SPREAD),
 912                                              init_once);
 913         if (ext4_inode_cachep == NULL)
 914                 return -ENOMEM;
 915         return 0;
 916 }
 917
 918 static void destroy_inodecache(void)
 919 {
 920         /*
 921          * Make sure all delayed rcu free inodes are flushed before we
 922          * destroy cache.
 923          */
 924         rcu_barrier();
 925         kmem_cache_destroy(ext4_inode_cachep);
 926 }
 927
 928 void ext4_clear_inode(struct inode *inode)
 929 {
 930         invalidate_inode_buffers(inode);
 931         clear_inode(inode);
 932         dquot_drop(inode);
 933         ext4_discard_preallocations(inode);
 934         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
 935         ext4_es_lru_del(inode);
 936         if (EXT4_I(inode)->jinode) {
 937                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
 938                                                EXT4_I(inode)->jinode);
 939                 jbd2_free_inode(EXT4_I(inode)->jinode);
 940                 EXT4_I(inode)->jinode = NULL;
 941         }
 942 }
 943
 944 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
 945                                         u64 ino, u32 generation)
 946 {
 947         struct inode *inode;
 948
 949         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 950                 return ERR_PTR(-ESTALE);
 951         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
 952                 return ERR_PTR(-ESTALE);
 953
 954         /* iget isn't really right if the inode is currently unallocated!!
 955          *
 956          * ext4_read_inode will return a bad_inode if the inode had been
 957          * deleted, so we should be safe.
 958          *
 959          * Currently we don't know the generation for parent directory, so
 960          * a generation of 0 means "accept any"
 961          */
 962         inode = ext4_iget(sb, ino);
 963         if (IS_ERR(inode))
 964                 return ERR_CAST(inode);
 965         if (generation && inode->i_generation != generation) {
 966                 iput(inode);
 967                 return ERR_PTR(-ESTALE);
 968         }
 969
 970         return inode;
 971 }
 972
 973 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
 974                                         int fh_len, int fh_type)
 975 {
 976         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 977                                     ext4_nfs_get_inode);
 978 }
 979
 980 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
 981                                         int fh_len, int fh_type)
 982 {
 983         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 984                                     ext4_nfs_get_inode);
 985 }
 986
 987 /*
 988  * Try to release metadata pages (indirect blocks, directories) which are
 989  * mapped via the block device.  Since these pages could have journal heads
 990  * which would prevent try_to_free_buffers() from freeing them, we must use
 991  * jbd2 layer's try_to_free_buffers() function to release them.
 992  */
 993 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
 994                                  gfp_t wait)
 995 {
 996         journal_t *journal = EXT4_SB(sb)->s_journal;
 997
 998         WARN_ON(PageChecked(page));
 999         if (!page_has_buffers(page))
1000                 return 0;
1001         if (journal)
1002                 return jbd2_journal_try_to_free_buffers(journal, page,
1003                                                         wait & ~__GFP_WAIT);
1004         return try_to_free_buffers(page);
1005 }
1006
1007 #ifdef CONFIG_QUOTA
1008 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1009 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1010
1011 static int ext4_write_dquot(struct dquot *dquot);
1012 static int ext4_acquire_dquot(struct dquot *dquot);
1013 static int ext4_release_dquot(struct dquot *dquot);
1014 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1015 static int ext4_write_info(struct super_block *sb, int type);
1016 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1017                          struct path *path);
1018 static int ext4_quota_on_sysfile(struct super_block *sb, int type,
1019                                  int format_id);
1020 static int ext4_quota_off(struct super_block *sb, int type);
1021 static int ext4_quota_off_sysfile(struct super_block *sb, int type);
1022 static int ext4_quota_on_mount(struct super_block *sb, int type);
1023 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1024                                size_t len, loff_t off);
1025 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1026                                 const char *data, size_t len, loff_t off);
1027 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1028                              unsigned int flags);
1029 static int ext4_enable_quotas(struct super_block *sb);
1030
1031 static const struct dquot_operations ext4_quota_operations = {
1032         .get_reserved_space = ext4_get_reserved_space,
1033         .write_dquot    = ext4_write_dquot,
1034         .acquire_dquot  = ext4_acquire_dquot,
1035         .release_dquot  = ext4_release_dquot,
1036         .mark_dirty     = ext4_mark_dquot_dirty,
1037         .write_info     = ext4_write_info,
1038         .alloc_dquot    = dquot_alloc,
1039         .destroy_dquot  = dquot_destroy,
1040 };
1041
1042 static const struct quotactl_ops ext4_qctl_operations = {
1043         .quota_on       = ext4_quota_on,
1044         .quota_off      = ext4_quota_off,
1045         .quota_sync     = dquot_quota_sync,
1046         .get_info       = dquot_get_dqinfo,
1047         .set_info       = dquot_set_dqinfo,
1048         .get_dqblk      = dquot_get_dqblk,
1049         .set_dqblk      = dquot_set_dqblk
1050 };
1051
1052 static const struct quotactl_ops ext4_qctl_sysfile_operations = {
1053         .quota_on_meta  = ext4_quota_on_sysfile,
1054         .quota_off      = ext4_quota_off_sysfile,
1055         .quota_sync     = dquot_quota_sync,
1056         .get_info       = dquot_get_dqinfo,
1057         .set_info       = dquot_set_dqinfo,
1058         .get_dqblk      = dquot_get_dqblk,
1059         .set_dqblk      = dquot_set_dqblk
1060 };
1061 #endif
1062
1063 static const struct super_operations ext4_sops = {
1064         .alloc_inode    = ext4_alloc_inode,
1065         .destroy_inode  = ext4_destroy_inode,
1066         .write_inode    = ext4_write_inode,
1067         .dirty_inode    = ext4_dirty_inode,
1068         .drop_inode     = ext4_drop_inode,
1069         .evict_inode    = ext4_evict_inode,
1070         .put_super      = ext4_put_super,
1071         .sync_fs        = ext4_sync_fs,
1072         .freeze_fs      = ext4_freeze,
1073         .unfreeze_fs    = ext4_unfreeze,
1074         .statfs         = ext4_statfs,
1075         .remount_fs     = ext4_remount,
1076         .show_options   = ext4_show_options,
1077 #ifdef CONFIG_QUOTA
1078         .quota_read     = ext4_quota_read,
1079         .quota_write    = ext4_quota_write,
1080 #endif
1081         .bdev_try_to_free_page = bdev_try_to_free_page,
1082 };
1083
1084 static const struct super_operations ext4_nojournal_sops = {
1085         .alloc_inode    = ext4_alloc_inode,
1086         .destroy_inode  = ext4_destroy_inode,
1087         .write_inode    = ext4_write_inode,
1088         .dirty_inode    = ext4_dirty_inode,
1089         .drop_inode     = ext4_drop_inode,
1090         .evict_inode    = ext4_evict_inode,
1091         .put_super      = ext4_put_super,
1092         .statfs         = ext4_statfs,
1093         .remount_fs     = ext4_remount,
1094         .show_options   = ext4_show_options,
1095 #ifdef CONFIG_QUOTA
1096         .quota_read     = ext4_quota_read,
1097         .quota_write    = ext4_quota_write,
1098 #endif
1099         .bdev_try_to_free_page = bdev_try_to_free_page,
1100 };
1101
1102 static const struct export_operations ext4_export_ops = {
1103         .fh_to_dentry = ext4_fh_to_dentry,
1104         .fh_to_parent = ext4_fh_to_parent,
1105         .get_parent = ext4_get_parent,
1106 };
1107
1108 enum {
1109         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1110         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1111         Opt_nouid32, Opt_debug, Opt_removed,
1112         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1113         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1114         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1115         Opt_journal_dev, Opt_journal_checksum, Opt_journal_async_commit,
1116         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1117         Opt_data_err_abort, Opt_data_err_ignore,
1118         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1119         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1120         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1121         Opt_usrquota, Opt_grpquota, Opt_i_version,
1122         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1123         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1124         Opt_inode_readahead_blks, Opt_journal_ioprio,
1125         Opt_dioread_nolock, Opt_dioread_lock,
1126         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1127         Opt_max_dir_size_kb,
1128 };
1129
1130 static const match_table_t tokens = {
1131         {Opt_bsd_df, "bsddf"},
1132         {Opt_minix_df, "minixdf"},
1133         {Opt_grpid, "grpid"},
1134         {Opt_grpid, "bsdgroups"},
1135         {Opt_nogrpid, "nogrpid"},
1136         {Opt_nogrpid, "sysvgroups"},
1137         {Opt_resgid, "resgid=%u"},
1138         {Opt_resuid, "resuid=%u"},
1139         {Opt_sb, "sb=%u"},
1140         {Opt_err_cont, "errors=continue"},
1141         {Opt_err_panic, "errors=panic"},
1142         {Opt_err_ro, "errors=remount-ro"},
1143         {Opt_nouid32, "nouid32"},
1144         {Opt_debug, "debug"},
1145         {Opt_removed, "oldalloc"},
1146         {Opt_removed, "orlov"},
1147         {Opt_user_xattr, "user_xattr"},
1148         {Opt_nouser_xattr, "nouser_xattr"},
1149         {Opt_acl, "acl"},
1150         {Opt_noacl, "noacl"},
1151         {Opt_noload, "norecovery"},
1152         {Opt_noload, "noload"},
1153         {Opt_removed, "nobh"},
1154         {Opt_removed, "bh"},
1155         {Opt_commit, "commit=%u"},
1156         {Opt_min_batch_time, "min_batch_time=%u"},
1157         {Opt_max_batch_time, "max_batch_time=%u"},
1158         {Opt_journal_dev, "journal_dev=%u"},
1159         {Opt_journal_checksum, "journal_checksum"},
1160         {Opt_journal_async_commit, "journal_async_commit"},
1161         {Opt_abort, "abort"},
1162         {Opt_data_journal, "data=journal"},
1163         {Opt_data_ordered, "data=ordered"},
1164         {Opt_data_writeback, "data=writeback"},
1165         {Opt_data_err_abort, "data_err=abort"},
1166         {Opt_data_err_ignore, "data_err=ignore"},
1167         {Opt_offusrjquota, "usrjquota="},
1168         {Opt_usrjquota, "usrjquota=%s"},
1169         {Opt_offgrpjquota, "grpjquota="},
1170         {Opt_grpjquota, "grpjquota=%s"},
1171         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1172         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1173         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1174         {Opt_grpquota, "grpquota"},
1175         {Opt_noquota, "noquota"},
1176         {Opt_quota, "quota"},
1177         {Opt_usrquota, "usrquota"},
1178         {Opt_barrier, "barrier=%u"},
1179         {Opt_barrier, "barrier"},
1180         {Opt_nobarrier, "nobarrier"},
1181         {Opt_i_version, "i_version"},
1182         {Opt_stripe, "stripe=%u"},
1183         {Opt_delalloc, "delalloc"},
1184         {Opt_nodelalloc, "nodelalloc"},
1185         {Opt_removed, "mblk_io_submit"},
1186         {Opt_removed, "nomblk_io_submit"},
1187         {Opt_block_validity, "block_validity"},
1188         {Opt_noblock_validity, "noblock_validity"},
1189         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1190         {Opt_journal_ioprio, "journal_ioprio=%u"},
1191         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1192         {Opt_auto_da_alloc, "auto_da_alloc"},
1193         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1194         {Opt_dioread_nolock, "dioread_nolock"},
1195         {Opt_dioread_lock, "dioread_lock"},
1196         {Opt_discard, "discard"},
1197         {Opt_nodiscard, "nodiscard"},
1198         {Opt_init_itable, "init_itable=%u"},
1199         {Opt_init_itable, "init_itable"},
1200         {Opt_noinit_itable, "noinit_itable"},
1201         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1202         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1203         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1204         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1205         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1206         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1207         {Opt_err, NULL},
1208 };
1209
1210 static ext4_fsblk_t get_sb_block(void **data)
1211 {
1212         ext4_fsblk_t    sb_block;
1213         char            *options = (char *) *data;
1214
1215         if (!options || strncmp(options, "sb=", 3) != 0)
1216                 return 1;       /* Default location */
1217
1218         options += 3;
1219         /* TODO: use simple_strtoll with >32bit ext4 */
1220         sb_block = simple_strtoul(options, &options, 0);
1221         if (*options && *options != ',') {
1222                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1223                        (char *) *data);
1224                 return 1;
1225         }
1226         if (*options == ',')
1227                 options++;
1228         *data = (void *) options;
1229
1230         return sb_block;
1231 }
1232
1233 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1234 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1235         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1236
1237 #ifdef CONFIG_QUOTA
1238 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1239 {
1240         struct ext4_sb_info *sbi = EXT4_SB(sb);
1241         char *qname;
1242         int ret = -1;
1243
1244         if (sb_any_quota_loaded(sb) &&
1245                 !sbi->s_qf_names[qtype]) {
1246                 ext4_msg(sb, KERN_ERR,
1247                         "Cannot change journaled "
1248                         "quota options when quota turned on");
1249                 return -1;
1250         }
1251         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) {
1252                 ext4_msg(sb, KERN_ERR, "Cannot set journaled quota options "
1253                          "when QUOTA feature is enabled");
1254                 return -1;
1255         }
1256         qname = match_strdup(args);
1257         if (!qname) {
1258                 ext4_msg(sb, KERN_ERR,
1259                         "Not enough memory for storing quotafile name");
1260                 return -1;
1261         }
1262         if (sbi->s_qf_names[qtype]) {
1263                 if (strcmp(sbi->s_qf_names[qtype], qname) == 0)
1264                         ret = 1;
1265                 else
1266                         ext4_msg(sb, KERN_ERR,
1267                                  "%s quota file already specified",
1268                                  QTYPE2NAME(qtype));
1269                 goto errout;
1270         }
1271         if (strchr(qname, '/')) {
1272                 ext4_msg(sb, KERN_ERR,
1273                         "quotafile must be on filesystem root");
1274                 goto errout;
1275         }
1276         sbi->s_qf_names[qtype] = qname;
1277         set_opt(sb, QUOTA);
1278         return 1;
1279 errout:
1280         kfree(qname);
1281         return ret;
1282 }
1283
1284 static int clear_qf_name(struct super_block *sb, int qtype)
1285 {
1286
1287         struct ext4_sb_info *sbi = EXT4_SB(sb);
1288
1289         if (sb_any_quota_loaded(sb) &&
1290                 sbi->s_qf_names[qtype]) {
1291                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1292                         " when quota turned on");
1293                 return -1;
1294         }
1295         kfree(sbi->s_qf_names[qtype]);
1296         sbi->s_qf_names[qtype] = NULL;
1297         return 1;
1298 }
1299 #endif
1300
1301 #define MOPT_SET        0x0001
1302 #define MOPT_CLEAR      0x0002
1303 #define MOPT_NOSUPPORT  0x0004
1304 #define MOPT_EXPLICIT   0x0008
1305 #define MOPT_CLEAR_ERR  0x0010
1306 #define MOPT_GTE0       0x0020
1307 #ifdef CONFIG_QUOTA
1308 #define MOPT_Q          0
1309 #define MOPT_QFMT       0x0040
1310 #else
1311 #define MOPT_Q          MOPT_NOSUPPORT
1312 #define MOPT_QFMT       MOPT_NOSUPPORT
1313 #endif
1314 #define MOPT_DATAJ      0x0080
1315 #define MOPT_NO_EXT2    0x0100
1316 #define MOPT_NO_EXT3    0x0200
1317 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1318
1319 static const struct mount_opts {
1320         int     token;
1321         int     mount_opt;
1322         int     flags;
1323 } ext4_mount_opts[] = {
1324         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1325         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1326         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1327         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1328         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1329         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1330         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1331          MOPT_EXT4_ONLY | MOPT_SET},
1332         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1333          MOPT_EXT4_ONLY | MOPT_CLEAR},
1334         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1335         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1336         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1337          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1338         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1339          MOPT_EXT4_ONLY | MOPT_CLEAR | MOPT_EXPLICIT},
1340         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1341          MOPT_EXT4_ONLY | MOPT_SET},
1342         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1343                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1344          MOPT_EXT4_ONLY | MOPT_SET},
1345         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1346         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1347         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1348         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1349         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1350          MOPT_NO_EXT2 | MOPT_SET},
1351         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1352          MOPT_NO_EXT2 | MOPT_CLEAR},
1353         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1354         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1355         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1356         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1357         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1358         {Opt_commit, 0, MOPT_GTE0},
1359         {Opt_max_batch_time, 0, MOPT_GTE0},
1360         {Opt_min_batch_time, 0, MOPT_GTE0},
1361         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1362         {Opt_init_itable, 0, MOPT_GTE0},
1363         {Opt_stripe, 0, MOPT_GTE0},
1364         {Opt_resuid, 0, MOPT_GTE0},
1365         {Opt_resgid, 0, MOPT_GTE0},
1366         {Opt_journal_dev, 0, MOPT_GTE0},
1367         {Opt_journal_ioprio, 0, MOPT_GTE0},
1368         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1369         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1370         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1371          MOPT_NO_EXT2 | MOPT_DATAJ},
1372         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1373         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1374 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1375         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1376         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1377 #else
1378         {Opt_acl, 0, MOPT_NOSUPPORT},
1379         {Opt_noacl, 0, MOPT_NOSUPPORT},
1380 #endif
1381         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1382         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1383         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1384         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1385                                                         MOPT_SET | MOPT_Q},
1386         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1387                                                         MOPT_SET | MOPT_Q},
1388         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1389                        EXT4_MOUNT_GRPQUOTA), MOPT_CLEAR | MOPT_Q},
1390         {Opt_usrjquota, 0, MOPT_Q},
1391         {Opt_grpjquota, 0, MOPT_Q},
1392         {Opt_offusrjquota, 0, MOPT_Q},
1393         {Opt_offgrpjquota, 0, MOPT_Q},
1394         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1395         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1396         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1397         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1398         {Opt_err, 0, 0}
1399 };
1400
1401 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1402                             substring_t *args, unsigned long *journal_devnum,
1403                             unsigned int *journal_ioprio, int is_remount)
1404 {
1405         struct ext4_sb_info *sbi = EXT4_SB(sb);
1406         const struct mount_opts *m;
1407         kuid_t uid;
1408         kgid_t gid;
1409         int arg = 0;
1410
1411 #ifdef CONFIG_QUOTA
1412         if (token == Opt_usrjquota)
1413                 return set_qf_name(sb, USRQUOTA, &args[0]);
1414         else if (token == Opt_grpjquota)
1415                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1416         else if (token == Opt_offusrjquota)
1417                 return clear_qf_name(sb, USRQUOTA);
1418         else if (token == Opt_offgrpjquota)
1419                 return clear_qf_name(sb, GRPQUOTA);
1420 #endif
1421         switch (token) {
1422         case Opt_noacl:
1423         case Opt_nouser_xattr:
1424                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1425                 break;
1426         case Opt_sb:
1427                 return 1;       /* handled by get_sb_block() */
1428         case Opt_removed:
1429                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1430                 return 1;
1431         case Opt_abort:
1432                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1433                 return 1;
1434         case Opt_i_version:
1435                 sb->s_flags |= MS_I_VERSION;
1436                 return 1;
1437         }
1438
1439         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1440                 if (token == m->token)
1441                         break;
1442
1443         if (m->token == Opt_err) {
1444                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1445                          "or missing value", opt);
1446                 return -1;
1447         }
1448
1449         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1450                 ext4_msg(sb, KERN_ERR,
1451                          "Mount option \"%s\" incompatible with ext2", opt);
1452                 return -1;
1453         }
1454         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1455                 ext4_msg(sb, KERN_ERR,
1456                          "Mount option \"%s\" incompatible with ext3", opt);
1457                 return -1;
1458         }
1459
1460         if (args->from && match_int(args, &arg))
1461                 return -1;
1462         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1463                 return -1;
1464         if (m->flags & MOPT_EXPLICIT)
1465                 set_opt2(sb, EXPLICIT_DELALLOC);
1466         if (m->flags & MOPT_CLEAR_ERR)
1467                 clear_opt(sb, ERRORS_MASK);
1468         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1469                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1470                          "options when quota turned on");
1471                 return -1;
1472         }
1473
1474         if (m->flags & MOPT_NOSUPPORT) {
1475                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1476         } else if (token == Opt_commit) {
1477                 if (arg == 0)
1478                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1479                 sbi->s_commit_interval = HZ * arg;
1480         } else if (token == Opt_max_batch_time) {
1481                 if (arg == 0)
1482                         arg = EXT4_DEF_MAX_BATCH_TIME;
1483                 sbi->s_max_batch_time = arg;
1484         } else if (token == Opt_min_batch_time) {
1485                 sbi->s_min_batch_time = arg;
1486         } else if (token == Opt_inode_readahead_blks) {
1487                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1488                         ext4_msg(sb, KERN_ERR,
1489                                  "EXT4-fs: inode_readahead_blks must be "
1490                                  "0 or a power of 2 smaller than 2^31");
1491                         return -1;
1492                 }
1493                 sbi->s_inode_readahead_blks = arg;
1494         } else if (token == Opt_init_itable) {
1495                 set_opt(sb, INIT_INODE_TABLE);
1496                 if (!args->from)
1497                         arg = EXT4_DEF_LI_WAIT_MULT;
1498                 sbi->s_li_wait_mult = arg;
1499         } else if (token == Opt_max_dir_size_kb) {
1500                 sbi->s_max_dir_size_kb = arg;
1501         } else if (token == Opt_stripe) {
1502                 sbi->s_stripe = arg;
1503         } else if (token == Opt_resuid) {
1504                 uid = make_kuid(current_user_ns(), arg);
1505                 if (!uid_valid(uid)) {
1506                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1507                         return -1;
1508                 }
1509                 sbi->s_resuid = uid;
1510         } else if (token == Opt_resgid) {
1511                 gid = make_kgid(current_user_ns(), arg);
1512                 if (!gid_valid(gid)) {
1513                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1514                         return -1;
1515                 }
1516                 sbi->s_resgid = gid;
1517         } else if (token == Opt_journal_dev) {
1518                 if (is_remount) {
1519                         ext4_msg(sb, KERN_ERR,
1520                                  "Cannot specify journal on remount");
1521                         return -1;
1522                 }
1523                 *journal_devnum = arg;
1524         } else if (token == Opt_journal_ioprio) {
1525                 if (arg > 7) {
1526                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1527                                  " (must be 0-7)");
1528                         return -1;
1529                 }
1530                 *journal_ioprio =
1531                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1532         } else if (m->flags & MOPT_DATAJ) {
1533                 if (is_remount) {
1534                         if (!sbi->s_journal)
1535                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1536                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1537                                 ext4_msg(sb, KERN_ERR,
1538                                          "Cannot change data mode on remount");
1539                                 return -1;
1540                         }
1541                 } else {
1542                         clear_opt(sb, DATA_FLAGS);
1543                         sbi->s_mount_opt |= m->mount_opt;
1544                 }
1545 #ifdef CONFIG_QUOTA
1546         } else if (m->flags & MOPT_QFMT) {
1547                 if (sb_any_quota_loaded(sb) &&
1548                     sbi->s_jquota_fmt != m->mount_opt) {
1549                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1550                                  "quota options when quota turned on");
1551                         return -1;
1552                 }
1553                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
1554                                                EXT4_FEATURE_RO_COMPAT_QUOTA)) {
1555                         ext4_msg(sb, KERN_ERR,
1556                                  "Cannot set journaled quota options "
1557                                  "when QUOTA feature is enabled");
1558                         return -1;
1559                 }
1560                 sbi->s_jquota_fmt = m->mount_opt;
1561 #endif
1562         } else {
1563                 if (!args->from)
1564                         arg = 1;
1565                 if (m->flags & MOPT_CLEAR)
1566                         arg = !arg;
1567                 else if (unlikely(!(m->flags & MOPT_SET))) {
1568                         ext4_msg(sb, KERN_WARNING,
1569                                  "buggy handling of option %s", opt);
1570                         WARN_ON(1);
1571                         return -1;
1572                 }
1573                 if (arg != 0)
1574                         sbi->s_mount_opt |= m->mount_opt;
1575                 else
1576                         sbi->s_mount_opt &= ~m->mount_opt;
1577         }
1578         return 1;
1579 }
1580
1581 static int parse_options(char *options, struct super_block *sb,
1582                          unsigned long *journal_devnum,
1583                          unsigned int *journal_ioprio,
1584                          int is_remount)
1585 {
1586         struct ext4_sb_info *sbi = EXT4_SB(sb);
1587         char *p;
1588         substring_t args[MAX_OPT_ARGS];
1589         int token;
1590
1591         if (!options)
1592                 return 1;
1593
1594         while ((p = strsep(&options, ",")) != NULL) {
1595                 if (!*p)
1596                         continue;
1597                 /*
1598                  * Initialize args struct so we know whether arg was
1599                  * found; some options take optional arguments.
1600                  */
1601                 args[0].to = args[0].from = NULL;
1602                 token = match_token(p, tokens, args);
1603                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1604                                      journal_ioprio, is_remount) < 0)
1605                         return 0;
1606         }
1607 #ifdef CONFIG_QUOTA
1608         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
1609             (test_opt(sb, USRQUOTA) || test_opt(sb, GRPQUOTA))) {
1610                 ext4_msg(sb, KERN_ERR, "Cannot set quota options when QUOTA "
1611                          "feature is enabled");
1612                 return 0;
1613         }
1614         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1615                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1616                         clear_opt(sb, USRQUOTA);
1617
1618                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1619                         clear_opt(sb, GRPQUOTA);
1620
1621                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1622                         ext4_msg(sb, KERN_ERR, "old and new quota "
1623                                         "format mixing");
1624                         return 0;
1625                 }
1626
1627                 if (!sbi->s_jquota_fmt) {
1628                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1629                                         "not specified");
1630                         return 0;
1631                 }
1632         } else {
1633                 if (sbi->s_jquota_fmt) {
1634                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1635                                         "specified with no journaling "
1636                                         "enabled");
1637                         return 0;
1638                 }
1639         }
1640 #endif
1641         if (test_opt(sb, DIOREAD_NOLOCK)) {
1642                 int blocksize =
1643                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
1644
1645                 if (blocksize < PAGE_CACHE_SIZE) {
1646                         ext4_msg(sb, KERN_ERR, "can't mount with "
1647                                  "dioread_nolock if block size != PAGE_SIZE");
1648                         return 0;
1649                 }
1650         }
1651         return 1;
1652 }
1653
1654 static inline void ext4_show_quota_options(struct seq_file *seq,
1655                                            struct super_block *sb)
1656 {
1657 #if defined(CONFIG_QUOTA)
1658         struct ext4_sb_info *sbi = EXT4_SB(sb);
1659
1660         if (sbi->s_jquota_fmt) {
1661                 char *fmtname = "";
1662
1663                 switch (sbi->s_jquota_fmt) {
1664                 case QFMT_VFS_OLD:
1665                         fmtname = "vfsold";
1666                         break;
1667                 case QFMT_VFS_V0:
1668                         fmtname = "vfsv0";
1669                         break;
1670                 case QFMT_VFS_V1:
1671                         fmtname = "vfsv1";
1672                         break;
1673                 }
1674                 seq_printf(seq, ",jqfmt=%s", fmtname);
1675         }
1676
1677         if (sbi->s_qf_names[USRQUOTA])
1678                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
1679
1680         if (sbi->s_qf_names[GRPQUOTA])
1681                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
1682
1683         if (test_opt(sb, USRQUOTA))
1684                 seq_puts(seq, ",usrquota");
1685
1686         if (test_opt(sb, GRPQUOTA))
1687                 seq_puts(seq, ",grpquota");
1688 #endif
1689 }
1690
1691 static const char *token2str(int token)
1692 {
1693         const struct match_token *t;
1694
1695         for (t = tokens; t->token != Opt_err; t++)
1696                 if (t->token == token && !strchr(t->pattern, '='))
1697                         break;
1698         return t->pattern;
1699 }
1700
1701 /*
1702  * Show an option if
1703  *  - it's set to a non-default value OR
1704  *  - if the per-sb default is different from the global default
1705  */
1706 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1707                               int nodefs)
1708 {
1709         struct ext4_sb_info *sbi = EXT4_SB(sb);
1710         struct ext4_super_block *es = sbi->s_es;
1711         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1712         const struct mount_opts *m;
1713         char sep = nodefs ? '\n' : ',';
1714
1715 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1716 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1717
1718         if (sbi->s_sb_block != 1)
1719                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1720
1721         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1722                 int want_set = m->flags & MOPT_SET;
1723                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1724                     (m->flags & MOPT_CLEAR_ERR))
1725                         continue;
1726                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1727                         continue; /* skip if same as the default */
1728                 if ((want_set &&
1729                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1730                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1731                         continue; /* select Opt_noFoo vs Opt_Foo */
1732                 SEQ_OPTS_PRINT("%s", token2str(m->token));
1733         }
1734
1735         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
1736             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1737                 SEQ_OPTS_PRINT("resuid=%u",
1738                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
1739         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
1740             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1741                 SEQ_OPTS_PRINT("resgid=%u",
1742                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
1743         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1744         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1745                 SEQ_OPTS_PUTS("errors=remount-ro");
1746         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1747                 SEQ_OPTS_PUTS("errors=continue");
1748         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1749                 SEQ_OPTS_PUTS("errors=panic");
1750         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
1751                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
1752         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
1753                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
1754         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
1755                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
1756         if (sb->s_flags & MS_I_VERSION)
1757                 SEQ_OPTS_PUTS("i_version");
1758         if (nodefs || sbi->s_stripe)
1759                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
1760         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
1761                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1762                         SEQ_OPTS_PUTS("data=journal");
1763                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1764                         SEQ_OPTS_PUTS("data=ordered");
1765                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1766                         SEQ_OPTS_PUTS("data=writeback");
1767         }
1768         if (nodefs ||
1769             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1770                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
1771                                sbi->s_inode_readahead_blks);
1772
1773         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
1774                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
1775                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
1776         if (nodefs || sbi->s_max_dir_size_kb)
1777                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
1778
1779         ext4_show_quota_options(seq, sb);
1780         return 0;
1781 }
1782
1783 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
1784 {
1785         return _ext4_show_options(seq, root->d_sb, 0);
1786 }
1787
1788 static int options_seq_show(struct seq_file *seq, void *offset)
1789 {
1790         struct super_block *sb = seq->private;
1791         int rc;
1792
1793         seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
1794         rc = _ext4_show_options(seq, sb, 1);
1795         seq_puts(seq, "\n");
1796         return rc;
1797 }
1798
1799 static int options_open_fs(struct inode *inode, struct file *file)
1800 {
1801         return single_open(file, options_seq_show, PDE(inode)->data);
1802 }
1803
1804 static const struct file_operations ext4_seq_options_fops = {
1805         .owner = THIS_MODULE,
1806         .open = options_open_fs,
1807         .read = seq_read,
1808         .llseek = seq_lseek,
1809         .release = single_release,
1810 };
1811
1812 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1813                             int read_only)
1814 {
1815         struct ext4_sb_info *sbi = EXT4_SB(sb);
1816         int res = 0;
1817
1818         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1819                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1820                          "forcing read-only mode");
1821                 res = MS_RDONLY;
1822         }
1823         if (read_only)
1824                 goto done;
1825         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1826                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1827                          "running e2fsck is recommended");
1828         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1829                 ext4_msg(sb, KERN_WARNING,
1830                          "warning: mounting fs with errors, "
1831                          "running e2fsck is recommended");
1832         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1833                  le16_to_cpu(es->s_mnt_count) >=
1834                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1835                 ext4_msg(sb, KERN_WARNING,
1836                          "warning: maximal mount count reached, "
1837                          "running e2fsck is recommended");
1838         else if (le32_to_cpu(es->s_checkinterval) &&
1839                 (le32_to_cpu(es->s_lastcheck) +
1840                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1841                 ext4_msg(sb, KERN_WARNING,
1842                          "warning: checktime reached, "
1843                          "running e2fsck is recommended");
1844         if (!sbi->s_journal)
1845                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1846         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1847                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1848         le16_add_cpu(&es->s_mnt_count, 1);
1849         es->s_mtime = cpu_to_le32(get_seconds());
1850         ext4_update_dynamic_rev(sb);
1851         if (sbi->s_journal)
1852                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1853
1854         ext4_commit_super(sb, 1);
1855 done:
1856         if (test_opt(sb, DEBUG))
1857                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1858                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1859                         sb->s_blocksize,
1860                         sbi->s_groups_count,
1861                         EXT4_BLOCKS_PER_GROUP(sb),
1862                         EXT4_INODES_PER_GROUP(sb),
1863                         sbi->s_mount_opt, sbi->s_mount_opt2);
1864
1865         cleancache_init_fs(sb);
1866         return res;
1867 }
1868
1869 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
1870 {
1871         struct ext4_sb_info *sbi = EXT4_SB(sb);
1872         struct flex_groups *new_groups;
1873         int size;
1874
1875         if (!sbi->s_log_groups_per_flex)
1876                 return 0;
1877
1878         size = ext4_flex_group(sbi, ngroup - 1) + 1;
1879         if (size <= sbi->s_flex_groups_allocated)
1880                 return 0;
1881
1882         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
1883         new_groups = ext4_kvzalloc(size, GFP_KERNEL);
1884         if (!new_groups) {
1885                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
1886                          size / (int) sizeof(struct flex_groups));
1887                 return -ENOMEM;
1888         }
1889
1890         if (sbi->s_flex_groups) {
1891                 memcpy(new_groups, sbi->s_flex_groups,
1892                        (sbi->s_flex_groups_allocated *
1893                         sizeof(struct flex_groups)));
1894                 ext4_kvfree(sbi->s_flex_groups);
1895         }
1896         sbi->s_flex_groups = new_groups;
1897         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
1898         return 0;
1899 }
1900
1901 static int ext4_fill_flex_info(struct super_block *sb)
1902 {
1903         struct ext4_sb_info *sbi = EXT4_SB(sb);
1904         struct ext4_group_desc *gdp = NULL;
1905         ext4_group_t flex_group;
1906         unsigned int groups_per_flex = 0;
1907         int i, err;
1908
1909         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1910         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
1911                 sbi->s_log_groups_per_flex = 0;
1912                 return 1;
1913         }
1914         groups_per_flex = 1U << sbi->s_log_groups_per_flex;
1915
1916         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
1917         if (err)
1918                 goto failed;
1919
1920         for (i = 0; i < sbi->s_groups_count; i++) {
1921                 gdp = ext4_get_group_desc(sb, i, NULL);
1922
1923                 flex_group = ext4_flex_group(sbi, i);
1924                 atomic_add(ext4_free_inodes_count(sb, gdp),
1925                            &sbi->s_flex_groups[flex_group].free_inodes);
1926                 atomic64_add(ext4_free_group_clusters(sb, gdp),
1927                              &sbi->s_flex_groups[flex_group].free_clusters);
1928                 atomic_add(ext4_used_dirs_count(sb, gdp),
1929                            &sbi->s_flex_groups[flex_group].used_dirs);
1930         }
1931
1932         return 1;
1933 failed:
1934         return 0;
1935 }
1936
1937 static __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1938                                    struct ext4_group_desc *gdp)
1939 {
1940         int offset;
1941         __u16 crc = 0;
1942         __le32 le_group = cpu_to_le32(block_group);
1943
1944         if ((sbi->s_es->s_feature_ro_compat &
1945              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))) {
1946                 /* Use new metadata_csum algorithm */
1947                 __u16 old_csum;
1948                 __u32 csum32;
1949
1950                 old_csum = gdp->bg_checksum;
1951                 gdp->bg_checksum = 0;
1952                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
1953                                      sizeof(le_group));
1954                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp,
1955                                      sbi->s_desc_size);
1956                 gdp->bg_checksum = old_csum;
1957
1958                 crc = csum32 & 0xFFFF;
1959                 goto out;
1960         }
1961
1962         /* old crc16 code */
1963         offset = offsetof(struct ext4_group_desc, bg_checksum);
1964
1965         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1966         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1967         crc = crc16(crc, (__u8 *)gdp, offset);
1968         offset += sizeof(gdp->bg_checksum); /* skip checksum */
1969         /* for checksum of struct ext4_group_desc do the rest...*/
1970         if ((sbi->s_es->s_feature_incompat &
1971              cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1972             offset < le16_to_cpu(sbi->s_es->s_desc_size))
1973                 crc = crc16(crc, (__u8 *)gdp + offset,
1974                             le16_to_cpu(sbi->s_es->s_desc_size) -
1975                                 offset);
1976
1977 out:
1978         return cpu_to_le16(crc);
1979 }
1980
1981 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
1982                                 struct ext4_group_desc *gdp)
1983 {
1984         if (ext4_has_group_desc_csum(sb) &&
1985             (gdp->bg_checksum != ext4_group_desc_csum(EXT4_SB(sb),
1986                                                       block_group, gdp)))
1987                 return 0;
1988
1989         return 1;
1990 }
1991
1992 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
1993                               struct ext4_group_desc *gdp)
1994 {
1995         if (!ext4_has_group_desc_csum(sb))
1996                 return;
1997         gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp);
1998 }
1999
2000 /* Called at mount-time, super-block is locked */
2001 static int ext4_check_descriptors(struct super_block *sb,
2002                                   ext4_group_t *first_not_zeroed)
2003 {
2004         struct ext4_sb_info *sbi = EXT4_SB(sb);
2005         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2006         ext4_fsblk_t last_block;
2007         ext4_fsblk_t block_bitmap;
2008         ext4_fsblk_t inode_bitmap;
2009         ext4_fsblk_t inode_table;
2010         int flexbg_flag = 0;
2011         ext4_group_t i, grp = sbi->s_groups_count;
2012
2013         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2014                 flexbg_flag = 1;
2015
2016         ext4_debug("Checking group descriptors");
2017
2018         for (i = 0; i < sbi->s_groups_count; i++) {
2019                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2020
2021                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2022                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2023                 else
2024                         last_block = first_block +
2025                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2026
2027                 if ((grp == sbi->s_groups_count) &&
2028                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2029                         grp = i;
2030
2031                 block_bitmap = ext4_block_bitmap(sb, gdp);
2032                 if (block_bitmap < first_block || block_bitmap > last_block) {
2033                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2034                                "Block bitmap for group %u not in group "
2035                                "(block %llu)!", i, block_bitmap);
2036                         return 0;
2037                 }
2038                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2039                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2040                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2041                                "Inode bitmap for group %u not in group "
2042                                "(block %llu)!", i, inode_bitmap);
2043                         return 0;
2044                 }
2045                 inode_table = ext4_inode_table(sb, gdp);
2046                 if (inode_table < first_block ||
2047                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2048                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2049                                "Inode table for group %u not in group "
2050                                "(block %llu)!", i, inode_table);
2051                         return 0;
2052                 }
2053                 ext4_lock_group(sb, i);
2054                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2055                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2056                                  "Checksum for group %u failed (%u!=%u)",
2057                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2058                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2059                         if (!(sb->s_flags & MS_RDONLY)) {
2060                                 ext4_unlock_group(sb, i);
2061                                 return 0;
2062                         }
2063                 }
2064                 ext4_unlock_group(sb, i);
2065                 if (!flexbg_flag)
2066                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2067         }
2068         if (NULL != first_not_zeroed)
2069                 *first_not_zeroed = grp;
2070
2071         ext4_free_blocks_count_set(sbi->s_es,
2072                                    EXT4_C2B(sbi, ext4_count_free_clusters(sb)));
2073         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
2074         return 1;
2075 }
2076
2077 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2078  * the superblock) which were deleted from all directories, but held open by
2079  * a process at the time of a crash.  We walk the list and try to delete these
2080  * inodes at recovery time (only with a read-write filesystem).
2081  *
2082  * In order to keep the orphan inode chain consistent during traversal (in
2083  * case of crash during recovery), we link each inode into the superblock
2084  * orphan list_head and handle it the same way as an inode deletion during
2085  * normal operation (which journals the operations for us).
2086  *
2087  * We only do an iget() and an iput() on each inode, which is very safe if we
2088  * accidentally point at an in-use or already deleted inode.  The worst that
2089  * can happen in this case is that we get a "bit already cleared" message from
2090  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2091  * e2fsck was run on this filesystem, and it must have already done the orphan
2092  * inode cleanup for us, so we can safely abort without any further action.
2093  */
2094 static void ext4_orphan_cleanup(struct super_block *sb,
2095                                 struct ext4_super_block *es)
2096 {
2097         unsigned int s_flags = sb->s_flags;
2098         int nr_orphans = 0, nr_truncates = 0;
2099 #ifdef CONFIG_QUOTA
2100         int i;
2101 #endif
2102         if (!es->s_last_orphan) {
2103                 jbd_debug(4, "no orphan inodes to clean up\n");
2104                 return;
2105         }
2106
2107         if (bdev_read_only(sb->s_bdev)) {
2108                 ext4_msg(sb, KERN_ERR, "write access "
2109                         "unavailable, skipping orphan cleanup");
2110                 return;
2111         }
2112
2113         /* Check if feature set would not allow a r/w mount */
2114         if (!ext4_feature_set_ok(sb, 0)) {
2115                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2116                          "unknown ROCOMPAT features");
2117                 return;
2118         }
2119
2120         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2121                 /* don't clear list on RO mount w/ errors */
2122                 if (es->s_last_orphan && !(s_flags & MS_RDONLY)) {
2123                         jbd_debug(1, "Errors on filesystem, "
2124                                   "clearing orphan list.\n");
2125                         es->s_last_orphan = 0;
2126                 }
2127                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2128                 return;
2129         }
2130
2131         if (s_flags & MS_RDONLY) {
2132                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2133                 sb->s_flags &= ~MS_RDONLY;
2134         }
2135 #ifdef CONFIG_QUOTA
2136         /* Needed for iput() to work correctly and not trash data */
2137         sb->s_flags |= MS_ACTIVE;
2138         /* Turn on quotas so that they are updated correctly */
2139         for (i = 0; i < MAXQUOTAS; i++) {
2140                 if (EXT4_SB(sb)->s_qf_names[i]) {
2141                         int ret = ext4_quota_on_mount(sb, i);
2142                         if (ret < 0)
2143                                 ext4_msg(sb, KERN_ERR,
2144                                         "Cannot turn on journaled "
2145                                         "quota: error %d", ret);
2146                 }
2147         }
2148 #endif
2149
2150         while (es->s_last_orphan) {
2151                 struct inode *inode;
2152
2153                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2154                 if (IS_ERR(inode)) {
2155                         es->s_last_orphan = 0;
2156                         break;
2157                 }
2158
2159                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2160                 dquot_initialize(inode);
2161                 if (inode->i_nlink) {
2162                         ext4_msg(sb, KERN_DEBUG,
2163                                 "%s: truncating inode %lu to %lld bytes",
2164                                 __func__, inode->i_ino, inode->i_size);
2165                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2166                                   inode->i_ino, inode->i_size);
2167                         mutex_lock(&inode->i_mutex);
2168                         ext4_truncate(inode);
2169                         mutex_unlock(&inode->i_mutex);
2170                         nr_truncates++;
2171                 } else {
2172                         ext4_msg(sb, KERN_DEBUG,
2173                                 "%s: deleting unreferenced inode %lu",
2174                                 __func__, inode->i_ino);
2175                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2176                                   inode->i_ino);
2177                         nr_orphans++;
2178                 }
2179                 iput(inode);  /* The delete magic happens here! */
2180         }
2181
2182 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2183
2184         if (nr_orphans)
2185                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2186                        PLURAL(nr_orphans));
2187         if (nr_truncates)
2188                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2189                        PLURAL(nr_truncates));
2190 #ifdef CONFIG_QUOTA
2191         /* Turn quotas off */
2192         for (i = 0; i < MAXQUOTAS; i++) {
2193                 if (sb_dqopt(sb)->files[i])
2194                         dquot_quota_off(sb, i);
2195         }
2196 #endif
2197         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2198 }
2199
2200 /*
2201  * Maximal extent format file size.
2202  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2203  * extent format containers, within a sector_t, and within i_blocks
2204  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2205  * so that won't be a limiting factor.
2206  *
2207  * However there is other limiting factor. We do store extents in the form
2208  * of starting block and length, hence the resulting length of the extent
2209  * covering maximum file size must fit into on-disk format containers as
2210  * well. Given that length is always by 1 unit bigger than max unit (because
2211  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2212  *
2213  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2214  */
2215 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2216 {
2217         loff_t res;
2218         loff_t upper_limit = MAX_LFS_FILESIZE;
2219
2220         /* small i_blocks in vfs inode? */
2221         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2222                 /*
2223                  * CONFIG_LBDAF is not enabled implies the inode
2224                  * i_block represent total blocks in 512 bytes
2225                  * 32 == size of vfs inode i_blocks * 8
2226                  */
2227                 upper_limit = (1LL << 32) - 1;
2228
2229                 /* total blocks in file system block size */
2230                 upper_limit >>= (blkbits - 9);
2231                 upper_limit <<= blkbits;
2232         }
2233
2234         /*
2235          * 32-bit extent-start container, ee_block. We lower the maxbytes
2236          * by one fs block, so ee_len can cover the extent of maximum file
2237          * size
2238          */
2239         res = (1LL << 32) - 1;
2240         res <<= blkbits;
2241
2242         /* Sanity check against vm- & vfs- imposed limits */
2243         if (res > upper_limit)
2244                 res = upper_limit;
2245
2246         return res;
2247 }
2248
2249 /*
2250  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2251  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2252  * We need to be 1 filesystem block less than the 2^48 sector limit.
2253  */
2254 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2255 {
2256         loff_t res = EXT4_NDIR_BLOCKS;
2257         int meta_blocks;
2258         loff_t upper_limit;
2259         /* This is calculated to be the largest file size for a dense, block
2260          * mapped file such that the file's total number of 512-byte sectors,
2261          * including data and all indirect blocks, does not exceed (2^48 - 1).
2262          *
2263          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2264          * number of 512-byte sectors of the file.
2265          */
2266
2267         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2268                 /*
2269                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2270                  * the inode i_block field represents total file blocks in
2271                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2272                  */
2273                 upper_limit = (1LL << 32) - 1;
2274
2275                 /* total blocks in file system block size */
2276                 upper_limit >>= (bits - 9);
2277
2278         } else {
2279                 /*
2280                  * We use 48 bit ext4_inode i_blocks
2281                  * With EXT4_HUGE_FILE_FL set the i_blocks
2282                  * represent total number of blocks in
2283                  * file system block size
2284                  */
2285                 upper_limit = (1LL << 48) - 1;
2286
2287         }
2288
2289         /* indirect blocks */
2290         meta_blocks = 1;
2291         /* double indirect blocks */
2292         meta_blocks += 1 + (1LL << (bits-2));
2293         /* tripple indirect blocks */
2294         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2295
2296         upper_limit -= meta_blocks;
2297         upper_limit <<= bits;
2298
2299         res += 1LL << (bits-2);
2300         res += 1LL << (2*(bits-2));
2301         res += 1LL << (3*(bits-2));
2302         res <<= bits;
2303         if (res > upper_limit)
2304                 res = upper_limit;
2305
2306         if (res > MAX_LFS_FILESIZE)
2307                 res = MAX_LFS_FILESIZE;
2308
2309         return res;
2310 }
2311
2312 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2313                                    ext4_fsblk_t logical_sb_block, int nr)
2314 {
2315         struct ext4_sb_info *sbi = EXT4_SB(sb);
2316         ext4_group_t bg, first_meta_bg;
2317         int has_super = 0;
2318
2319         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2320
2321         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2322             nr < first_meta_bg)
2323                 return logical_sb_block + nr + 1;
2324         bg = sbi->s_desc_per_block * nr;
2325         if (ext4_bg_has_super(sb, bg))
2326                 has_super = 1;
2327
2328         return (has_super + ext4_group_first_block_no(sb, bg));
2329 }
2330
2331 /**
2332  * ext4_get_stripe_size: Get the stripe size.
2333  * @sbi: In memory super block info
2334  *
2335  * If we have specified it via mount option, then
2336  * use the mount option value. If the value specified at mount time is
2337  * greater than the blocks per group use the super block value.
2338  * If the super block value is greater than blocks per group return 0.
2339  * Allocator needs it be less than blocks per group.
2340  *
2341  */
2342 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2343 {
2344         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2345         unsigned long stripe_width =
2346                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2347         int ret;
2348
2349         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2350                 ret = sbi->s_stripe;
2351         else if (stripe_width <= sbi->s_blocks_per_group)
2352                 ret = stripe_width;
2353         else if (stride <= sbi->s_blocks_per_group)
2354                 ret = stride;
2355         else
2356                 ret = 0;
2357
2358         /*
2359          * If the stripe width is 1, this makes no sense and
2360          * we set it to 0 to turn off stripe handling code.
2361          */
2362         if (ret <= 1)
2363                 ret = 0;
2364
2365         return ret;
2366 }
2367
2368 /* sysfs supprt */
2369
2370 struct ext4_attr {
2371         struct attribute attr;
2372         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2373         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2374                          const char *, size_t);
2375         int offset;
2376 };
2377
2378 static int parse_strtoul(const char *buf,
2379                 unsigned long max, unsigned long *value)
2380 {
2381         char *endp;
2382
2383         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2384         endp = skip_spaces(endp);
2385         if (*endp || *value > max)
2386                 return -EINVAL;
2387
2388         return 0;
2389 }
2390
2391 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2392                                               struct ext4_sb_info *sbi,
2393                                               char *buf)
2394 {
2395         return snprintf(buf, PAGE_SIZE, "%llu\n",
2396                 (s64) EXT4_C2B(sbi,
2397                         percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2398 }
2399
2400 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2401                                          struct ext4_sb_info *sbi, char *buf)
2402 {
2403         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2404
2405         if (!sb->s_bdev->bd_part)
2406                 return snprintf(buf, PAGE_SIZE, "0\n");
2407         return snprintf(buf, PAGE_SIZE, "%lu\n",
2408                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2409                          sbi->s_sectors_written_start) >> 1);
2410 }
2411
2412 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2413                                           struct ext4_sb_info *sbi, char *buf)
2414 {
2415         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2416
2417         if (!sb->s_bdev->bd_part)
2418                 return snprintf(buf, PAGE_SIZE, "0\n");
2419         return snprintf(buf, PAGE_SIZE, "%llu\n",
2420                         (unsigned long long)(sbi->s_kbytes_written +
2421                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2422                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2423 }
2424
2425 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2426                                           struct ext4_sb_info *sbi,
2427                                           const char *buf, size_t count)
2428 {
2429         unsigned long t;
2430
2431         if (parse_strtoul(buf, 0x40000000, &t))
2432                 return -EINVAL;
2433
2434         if (t && !is_power_of_2(t))
2435                 return -EINVAL;
2436
2437         sbi->s_inode_readahead_blks = t;
2438         return count;
2439 }
2440
2441 static ssize_t sbi_ui_show(struct ext4_attr *a,
2442                            struct ext4_sb_info *sbi, char *buf)
2443 {
2444         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2445
2446         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2447 }
2448
2449 static ssize_t sbi_ui_store(struct ext4_attr *a,
2450                             struct ext4_sb_info *sbi,
2451                             const char *buf, size_t count)
2452 {
2453         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2454         unsigned long t;
2455
2456         if (parse_strtoul(buf, 0xffffffff, &t))
2457                 return -EINVAL;
2458         *ui = t;
2459         return count;
2460 }
2461
2462 static ssize_t trigger_test_error(struct ext4_attr *a,
2463                                   struct ext4_sb_info *sbi,
2464                                   const char *buf, size_t count)
2465 {
2466         int len = count;
2467
2468         if (!capable(CAP_SYS_ADMIN))
2469                 return -EPERM;
2470
2471         if (len && buf[len-1] == '\n')
2472                 len--;
2473
2474         if (len)
2475                 ext4_error(sbi->s_sb, "%.*s", len, buf);
2476         return count;
2477 }
2478
2479 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2480 static struct ext4_attr ext4_attr_##_name = {                   \
2481         .attr = {.name = __stringify(_name), .mode = _mode },   \
2482         .show   = _show,                                        \
2483         .store  = _store,                                       \
2484         .offset = offsetof(struct ext4_sb_info, _elname),       \
2485 }
2486 #define EXT4_ATTR(name, mode, show, store) \
2487 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2488
2489 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2490 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2491 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2492 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2493         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2494 #define ATTR_LIST(name) &ext4_attr_##name.attr
2495
2496 EXT4_RO_ATTR(delayed_allocation_blocks);
2497 EXT4_RO_ATTR(session_write_kbytes);
2498 EXT4_RO_ATTR(lifetime_write_kbytes);
2499 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2500                  inode_readahead_blks_store, s_inode_readahead_blks);
2501 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2502 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2503 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2504 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2505 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2506 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2507 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2508 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2509 EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);
2510 EXT4_ATTR(trigger_fs_error, 0200, NULL, trigger_test_error);
2511
2512 static struct attribute *ext4_attrs[] = {
2513         ATTR_LIST(delayed_allocation_blocks),
2514         ATTR_LIST(session_write_kbytes),
2515         ATTR_LIST(lifetime_write_kbytes),
2516         ATTR_LIST(inode_readahead_blks),
2517         ATTR_LIST(inode_goal),
2518         ATTR_LIST(mb_stats),
2519         ATTR_LIST(mb_max_to_scan),
2520         ATTR_LIST(mb_min_to_scan),
2521         ATTR_LIST(mb_order2_req),
2522         ATTR_LIST(mb_stream_req),
2523         ATTR_LIST(mb_group_prealloc),
2524         ATTR_LIST(max_writeback_mb_bump),
2525         ATTR_LIST(extent_max_zeroout_kb),
2526         ATTR_LIST(trigger_fs_error),
2527         NULL,
2528 };
2529
2530 /* Features this copy of ext4 supports */
2531 EXT4_INFO_ATTR(lazy_itable_init);
2532 EXT4_INFO_ATTR(batched_discard);
2533 EXT4_INFO_ATTR(meta_bg_resize);
2534
2535 static struct attribute *ext4_feat_attrs[] = {
2536         ATTR_LIST(lazy_itable_init),
2537         ATTR_LIST(batched_discard),
2538         ATTR_LIST(meta_bg_resize),
2539         NULL,
2540 };
2541
2542 static ssize_t ext4_attr_show(struct kobject *kobj,
2543                               struct attribute *attr, char *buf)
2544 {
2545         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2546                                                 s_kobj);
2547         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2548
2549         return a->show ? a->show(a, sbi, buf) : 0;
2550 }
2551
2552 static ssize_t ext4_attr_store(struct kobject *kobj,
2553                                struct attribute *attr,
2554                                const char *buf, size_t len)
2555 {
2556         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2557                                                 s_kobj);
2558         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2559
2560         return a->store ? a->store(a, sbi, buf, len) : 0;
2561 }
2562
2563 static void ext4_sb_release(struct kobject *kobj)
2564 {
2565         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2566                                                 s_kobj);
2567         complete(&sbi->s_kobj_unregister);
2568 }
2569
2570 static const struct sysfs_ops ext4_attr_ops = {
2571         .show   = ext4_attr_show,
2572         .store  = ext4_attr_store,
2573 };
2574
2575 static struct kobj_type ext4_ktype = {
2576         .default_attrs  = ext4_attrs,
2577         .sysfs_ops      = &ext4_attr_ops,
2578         .release        = ext4_sb_release,
2579 };
2580
2581 static void ext4_feat_release(struct kobject *kobj)
2582 {
2583         complete(&ext4_feat->f_kobj_unregister);
2584 }
2585
2586 static struct kobj_type ext4_feat_ktype = {
2587         .default_attrs  = ext4_feat_attrs,
2588         .sysfs_ops      = &ext4_attr_ops,
2589         .release        = ext4_feat_release,
2590 };
2591
2592 /*
2593  * Check whether this filesystem can be mounted based on
2594  * the features present and the RDONLY/RDWR mount requested.
2595  * Returns 1 if this filesystem can be mounted as requested,
2596  * 0 if it cannot be.
2597  */
2598 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2599 {
2600         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2601                 ext4_msg(sb, KERN_ERR,
2602                         "Couldn't mount because of "
2603                         "unsupported optional features (%x)",
2604                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2605                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2606                 return 0;
2607         }
2608
2609         if (readonly)
2610                 return 1;
2611
2612         /* Check that feature set is OK for a read-write mount */
2613         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2614                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2615                          "unsupported optional features (%x)",
2616                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2617                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2618                 return 0;
2619         }
2620         /*
2621          * Large file size enabled file system can only be mounted
2622          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2623          */
2624         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2625                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2626                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2627                                  "cannot be mounted RDWR without "
2628                                  "CONFIG_LBDAF");
2629                         return 0;
2630                 }
2631         }
2632         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2633             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2634                 ext4_msg(sb, KERN_ERR,
2635                          "Can't support bigalloc feature without "
2636                          "extents feature\n");
2637                 return 0;
2638         }
2639
2640 #ifndef CONFIG_QUOTA
2641         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
2642             !readonly) {
2643                 ext4_msg(sb, KERN_ERR,
2644                          "Filesystem with quota feature cannot be mounted RDWR "
2645                          "without CONFIG_QUOTA");
2646                 return 0;
2647         }
2648 #endif  /* CONFIG_QUOTA */
2649         return 1;
2650 }
2651
2652 /*
2653  * This function is called once a day if we have errors logged
2654  * on the file system
2655  */
2656 static void print_daily_error_info(unsigned long arg)
2657 {
2658         struct super_block *sb = (struct super_block *) arg;
2659         struct ext4_sb_info *sbi;
2660         struct ext4_super_block *es;
2661
2662         sbi = EXT4_SB(sb);
2663         es = sbi->s_es;
2664
2665         if (es->s_error_count)
2666                 ext4_msg(sb, KERN_NOTICE, "error count: %u",
2667                          le32_to_cpu(es->s_error_count));
2668         if (es->s_first_error_time) {
2669                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at %u: %.*s:%d",
2670                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2671                        (int) sizeof(es->s_first_error_func),
2672                        es->s_first_error_func,
2673                        le32_to_cpu(es->s_first_error_line));
2674                 if (es->s_first_error_ino)
2675                         printk(": inode %u",
2676                                le32_to_cpu(es->s_first_error_ino));
2677                 if (es->s_first_error_block)
2678                         printk(": block %llu", (unsigned long long)
2679                                le64_to_cpu(es->s_first_error_block));
2680                 printk("\n");
2681         }
2682         if (es->s_last_error_time) {
2683                 printk(KERN_NOTICE "EXT4-fs (%s): last error at %u: %.*s:%d",
2684                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2685                        (int) sizeof(es->s_last_error_func),
2686                        es->s_last_error_func,
2687                        le32_to_cpu(es->s_last_error_line));
2688                 if (es->s_last_error_ino)
2689                         printk(": inode %u",
2690                                le32_to_cpu(es->s_last_error_ino));
2691                 if (es->s_last_error_block)
2692                         printk(": block %llu", (unsigned long long)
2693                                le64_to_cpu(es->s_last_error_block));
2694                 printk("\n");
2695         }
2696         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2697 }
2698
2699 /* Find next suitable group and run ext4_init_inode_table */
2700 static int ext4_run_li_request(struct ext4_li_request *elr)
2701 {
2702         struct ext4_group_desc *gdp = NULL;
2703         ext4_group_t group, ngroups;
2704         struct super_block *sb;
2705         unsigned long timeout = 0;
2706         int ret = 0;
2707
2708         sb = elr->lr_super;
2709         ngroups = EXT4_SB(sb)->s_groups_count;
2710
2711         sb_start_write(sb);
2712         for (group = elr->lr_next_group; group < ngroups; group++) {
2713                 gdp = ext4_get_group_desc(sb, group, NULL);
2714                 if (!gdp) {
2715                         ret = 1;
2716                         break;
2717                 }
2718
2719                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2720                         break;
2721         }
2722
2723         if (group >= ngroups)
2724                 ret = 1;
2725
2726         if (!ret) {
2727                 timeout = jiffies;
2728                 ret = ext4_init_inode_table(sb, group,
2729                                             elr->lr_timeout ? 0 : 1);
2730                 if (elr->lr_timeout == 0) {
2731                         timeout = (jiffies - timeout) *
2732                                   elr->lr_sbi->s_li_wait_mult;
2733                         elr->lr_timeout = timeout;
2734                 }
2735                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2736                 elr->lr_next_group = group + 1;
2737         }
2738         sb_end_write(sb);
2739
2740         return ret;
2741 }
2742
2743 /*
2744  * Remove lr_request from the list_request and free the
2745  * request structure. Should be called with li_list_mtx held
2746  */
2747 static void ext4_remove_li_request(struct ext4_li_request *elr)
2748 {
2749         struct ext4_sb_info *sbi;
2750
2751         if (!elr)
2752                 return;
2753
2754         sbi = elr->lr_sbi;
2755
2756         list_del(&elr->lr_request);
2757         sbi->s_li_request = NULL;
2758         kfree(elr);
2759 }
2760
2761 static void ext4_unregister_li_request(struct super_block *sb)
2762 {
2763         mutex_lock(&ext4_li_mtx);
2764         if (!ext4_li_info) {
2765                 mutex_unlock(&ext4_li_mtx);
2766                 return;
2767         }
2768
2769         mutex_lock(&ext4_li_info->li_list_mtx);
2770         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2771         mutex_unlock(&ext4_li_info->li_list_mtx);
2772         mutex_unlock(&ext4_li_mtx);
2773 }
2774
2775 static struct task_struct *ext4_lazyinit_task;
2776
2777 /*
2778  * This is the function where ext4lazyinit thread lives. It walks
2779  * through the request list searching for next scheduled filesystem.
2780  * When such a fs is found, run the lazy initialization request
2781  * (ext4_rn_li_request) and keep track of the time spend in this
2782  * function. Based on that time we compute next schedule time of
2783  * the request. When walking through the list is complete, compute
2784  * next waking time and put itself into sleep.
2785  */
2786 static int ext4_lazyinit_thread(void *arg)
2787 {
2788         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2789         struct list_head *pos, *n;
2790         struct ext4_li_request *elr;
2791         unsigned long next_wakeup, cur;
2792
2793         BUG_ON(NULL == eli);
2794
2795 cont_thread:
2796         while (true) {
2797                 next_wakeup = MAX_JIFFY_OFFSET;
2798
2799                 mutex_lock(&eli->li_list_mtx);
2800                 if (list_empty(&eli->li_request_list)) {
2801                         mutex_unlock(&eli->li_list_mtx);
2802                         goto exit_thread;
2803                 }
2804
2805                 list_for_each_safe(pos, n, &eli->li_request_list) {
2806                         elr = list_entry(pos, struct ext4_li_request,
2807                                          lr_request);
2808
2809                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2810                                 if (ext4_run_li_request(elr) != 0) {
2811                                         /* error, remove the lazy_init job */
2812                                         ext4_remove_li_request(elr);
2813                                         continue;
2814                                 }
2815                         }
2816
2817                         if (time_before(elr->lr_next_sched, next_wakeup))
2818                                 next_wakeup = elr->lr_next_sched;
2819                 }
2820                 mutex_unlock(&eli->li_list_mtx);
2821
2822                 try_to_freeze();
2823
2824                 cur = jiffies;
2825                 if ((time_after_eq(cur, next_wakeup)) ||
2826                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2827                         cond_resched();
2828                         continue;
2829                 }
2830
2831                 schedule_timeout_interruptible(next_wakeup - cur);
2832
2833                 if (kthread_should_stop()) {
2834                         ext4_clear_request_list();
2835                         goto exit_thread;
2836                 }
2837         }
2838
2839 exit_thread:
2840         /*
2841          * It looks like the request list is empty, but we need
2842          * to check it under the li_list_mtx lock, to prevent any
2843          * additions into it, and of course we should lock ext4_li_mtx
2844          * to atomically free the list and ext4_li_info, because at
2845          * this point another ext4 filesystem could be registering
2846          * new one.
2847          */
2848         mutex_lock(&ext4_li_mtx);
2849         mutex_lock(&eli->li_list_mtx);
2850         if (!list_empty(&eli->li_request_list)) {
2851                 mutex_unlock(&eli->li_list_mtx);
2852                 mutex_unlock(&ext4_li_mtx);
2853                 goto cont_thread;
2854         }
2855         mutex_unlock(&eli->li_list_mtx);
2856         kfree(ext4_li_info);
2857         ext4_li_info = NULL;
2858         mutex_unlock(&ext4_li_mtx);
2859
2860         return 0;
2861 }
2862
2863 static void ext4_clear_request_list(void)
2864 {
2865         struct list_head *pos, *n;
2866         struct ext4_li_request *elr;
2867
2868         mutex_lock(&ext4_li_info->li_list_mtx);
2869         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2870                 elr = list_entry(pos, struct ext4_li_request,
2871                                  lr_request);
2872                 ext4_remove_li_request(elr);
2873         }
2874         mutex_unlock(&ext4_li_info->li_list_mtx);
2875 }
2876
2877 static int ext4_run_lazyinit_thread(void)
2878 {
2879         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
2880                                          ext4_li_info, "ext4lazyinit");
2881         if (IS_ERR(ext4_lazyinit_task)) {
2882                 int err = PTR_ERR(ext4_lazyinit_task);
2883                 ext4_clear_request_list();
2884                 kfree(ext4_li_info);
2885                 ext4_li_info = NULL;
2886                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
2887                                  "initialization thread\n",
2888                                  err);
2889                 return err;
2890         }
2891         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2892         return 0;
2893 }
2894
2895 /*
2896  * Check whether it make sense to run itable init. thread or not.
2897  * If there is at least one uninitialized inode table, return
2898  * corresponding group number, else the loop goes through all
2899  * groups and return total number of groups.
2900  */
2901 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2902 {
2903         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2904         struct ext4_group_desc *gdp = NULL;
2905
2906         for (group = 0; group < ngroups; group++) {
2907                 gdp = ext4_get_group_desc(sb, group, NULL);
2908                 if (!gdp)
2909                         continue;
2910
2911                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2912                         break;
2913         }
2914
2915         return group;
2916 }
2917
2918 static int ext4_li_info_new(void)
2919 {
2920         struct ext4_lazy_init *eli = NULL;
2921
2922         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2923         if (!eli)
2924                 return -ENOMEM;
2925
2926         INIT_LIST_HEAD(&eli->li_request_list);
2927         mutex_init(&eli->li_list_mtx);
2928
2929         eli->li_state |= EXT4_LAZYINIT_QUIT;
2930
2931         ext4_li_info = eli;
2932
2933         return 0;
2934 }
2935
2936 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2937                                             ext4_group_t start)
2938 {
2939         struct ext4_sb_info *sbi = EXT4_SB(sb);
2940         struct ext4_li_request *elr;
2941         unsigned long rnd;
2942
2943         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
2944         if (!elr)
2945                 return NULL;
2946
2947         elr->lr_super = sb;
2948         elr->lr_sbi = sbi;
2949         elr->lr_next_group = start;
2950
2951         /*
2952          * Randomize first schedule time of the request to
2953          * spread the inode table initialization requests
2954          * better.
2955          */
2956         get_random_bytes(&rnd, sizeof(rnd));
2957         elr->lr_next_sched = jiffies + (unsigned long)rnd %
2958                              (EXT4_DEF_LI_MAX_START_DELAY * HZ);
2959
2960         return elr;
2961 }
2962
2963 int ext4_register_li_request(struct super_block *sb,
2964                              ext4_group_t first_not_zeroed)
2965 {
2966         struct ext4_sb_info *sbi = EXT4_SB(sb);
2967         struct ext4_li_request *elr = NULL;
2968         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
2969         int ret = 0;
2970
2971         mutex_lock(&ext4_li_mtx);
2972         if (sbi->s_li_request != NULL) {
2973                 /*
2974                  * Reset timeout so it can be computed again, because
2975                  * s_li_wait_mult might have changed.
2976                  */
2977                 sbi->s_li_request->lr_timeout = 0;
2978                 goto out;
2979         }
2980
2981         if (first_not_zeroed == ngroups ||
2982             (sb->s_flags & MS_RDONLY) ||
2983             !test_opt(sb, INIT_INODE_TABLE))
2984                 goto out;
2985
2986         elr = ext4_li_request_new(sb, first_not_zeroed);
2987         if (!elr) {
2988                 ret = -ENOMEM;
2989                 goto out;
2990         }
2991
2992         if (NULL == ext4_li_info) {
2993                 ret = ext4_li_info_new();
2994                 if (ret)
2995                         goto out;
2996         }
2997
2998         mutex_lock(&ext4_li_info->li_list_mtx);
2999         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3000         mutex_unlock(&ext4_li_info->li_list_mtx);
3001
3002         sbi->s_li_request = elr;
3003         /*
3004          * set elr to NULL here since it has been inserted to
3005          * the request_list and the removal and free of it is
3006          * handled by ext4_clear_request_list from now on.
3007          */
3008         elr = NULL;
3009
3010         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3011                 ret = ext4_run_lazyinit_thread();
3012                 if (ret)
3013                         goto out;
3014         }
3015 out:
3016         mutex_unlock(&ext4_li_mtx);
3017         if (ret)
3018                 kfree(elr);
3019         return ret;
3020 }
3021
3022 /*
3023  * We do not need to lock anything since this is called on
3024  * module unload.
3025  */
3026 static void ext4_destroy_lazyinit_thread(void)
3027 {
3028         /*
3029          * If thread exited earlier
3030          * there's nothing to be done.
3031          */
3032         if (!ext4_li_info || !ext4_lazyinit_task)
3033                 return;
3034
3035         kthread_stop(ext4_lazyinit_task);
3036 }
3037
3038 static int set_journal_csum_feature_set(struct super_block *sb)
3039 {
3040         int ret = 1;
3041         int compat, incompat;
3042         struct ext4_sb_info *sbi = EXT4_SB(sb);
3043
3044         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3045                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3046                 /* journal checksum v2 */
3047                 compat = 0;
3048                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V2;
3049         } else {
3050                 /* journal checksum v1 */
3051                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3052                 incompat = 0;
3053         }
3054
3055         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3056                 ret = jbd2_journal_set_features(sbi->s_journal,
3057                                 compat, 0,
3058                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3059                                 incompat);
3060         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3061                 ret = jbd2_journal_set_features(sbi->s_journal,
3062                                 compat, 0,
3063                                 incompat);
3064                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3065                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3066         } else {
3067                 jbd2_journal_clear_features(sbi->s_journal,
3068                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3069                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3070                                 JBD2_FEATURE_INCOMPAT_CSUM_V2);
3071         }
3072
3073         return ret;
3074 }
3075
3076 /*
3077  * Note: calculating the overhead so we can be compatible with
3078  * historical BSD practice is quite difficult in the face of
3079  * clusters/bigalloc.  This is because multiple metadata blocks from
3080  * different block group can end up in the same allocation cluster.
3081  * Calculating the exact overhead in the face of clustered allocation
3082  * requires either O(all block bitmaps) in memory or O(number of block
3083  * groups**2) in time.  We will still calculate the superblock for
3084  * older file systems --- and if we come across with a bigalloc file
3085  * system with zero in s_overhead_clusters the estimate will be close to
3086  * correct especially for very large cluster sizes --- but for newer
3087  * file systems, it's better to calculate this figure once at mkfs
3088  * time, and store it in the superblock.  If the superblock value is
3089  * present (even for non-bigalloc file systems), we will use it.
3090  */
3091 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3092                           char *buf)
3093 {
3094         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3095         struct ext4_group_desc  *gdp;
3096         ext4_fsblk_t            first_block, last_block, b;
3097         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3098         int                     s, j, count = 0;
3099
3100         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC))
3101                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3102                         sbi->s_itb_per_group + 2);
3103
3104         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3105                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3106         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3107         for (i = 0; i < ngroups; i++) {
3108                 gdp = ext4_get_group_desc(sb, i, NULL);
3109                 b = ext4_block_bitmap(sb, gdp);
3110                 if (b >= first_block && b <= last_block) {
3111                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3112                         count++;
3113                 }
3114                 b = ext4_inode_bitmap(sb, gdp);
3115                 if (b >= first_block && b <= last_block) {
3116                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3117                         count++;
3118                 }
3119                 b = ext4_inode_table(sb, gdp);
3120                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3121                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3122                                 int c = EXT4_B2C(sbi, b - first_block);
3123                                 ext4_set_bit(c, buf);
3124                                 count++;
3125                         }
3126                 if (i != grp)
3127                         continue;
3128                 s = 0;
3129                 if (ext4_bg_has_super(sb, grp)) {
3130                         ext4_set_bit(s++, buf);
3131                         count++;
3132                 }
3133                 for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) {
3134                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3135                         count++;
3136                 }
3137         }
3138         if (!count)
3139                 return 0;
3140         return EXT4_CLUSTERS_PER_GROUP(sb) -
3141                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3142 }
3143
3144 /*
3145  * Compute the overhead and stash it in sbi->s_overhead
3146  */
3147 int ext4_calculate_overhead(struct super_block *sb)
3148 {
3149         struct ext4_sb_info *sbi = EXT4_SB(sb);
3150         struct ext4_super_block *es = sbi->s_es;
3151         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3152         ext4_fsblk_t overhead = 0;
3153         char *buf = (char *) get_zeroed_page(GFP_KERNEL);
3154
3155         if (!buf)
3156                 return -ENOMEM;
3157
3158         /*
3159          * Compute the overhead (FS structures).  This is constant
3160          * for a given filesystem unless the number of block groups
3161          * changes so we cache the previous value until it does.
3162          */
3163
3164         /*
3165          * All of the blocks before first_data_block are overhead
3166          */
3167         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3168
3169         /*
3170          * Add the overhead found in each block group
3171          */
3172         for (i = 0; i < ngroups; i++) {
3173                 int blks;
3174
3175                 blks = count_overhead(sb, i, buf);
3176                 overhead += blks;
3177                 if (blks)
3178                         memset(buf, 0, PAGE_SIZE);
3179                 cond_resched();
3180         }
3181         /* Add the journal blocks as well */
3182         if (sbi->s_journal)
3183                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3184
3185         sbi->s_overhead = overhead;
3186         smp_wmb();
3187         free_page((unsigned long) buf);
3188         return 0;
3189 }
3190
3191 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3192 {
3193         char *orig_data = kstrdup(data, GFP_KERNEL);
3194         struct buffer_head *bh;
3195         struct ext4_super_block *es = NULL;
3196         struct ext4_sb_info *sbi;
3197         ext4_fsblk_t block;
3198         ext4_fsblk_t sb_block = get_sb_block(&data);
3199         ext4_fsblk_t logical_sb_block;
3200         unsigned long offset = 0;
3201         unsigned long journal_devnum = 0;
3202         unsigned long def_mount_opts;
3203         struct inode *root;
3204         char *cp;
3205         const char *descr;
3206         int ret = -ENOMEM;
3207         int blocksize, clustersize;
3208         unsigned int db_count;
3209         unsigned int i;
3210         int needs_recovery, has_huge_files, has_bigalloc;
3211         __u64 blocks_count;
3212         int err = 0;
3213         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3214         ext4_group_t first_not_zeroed;
3215
3216         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3217         if (!sbi)
3218                 goto out_free_orig;
3219
3220         sbi->s_blockgroup_lock =
3221                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3222         if (!sbi->s_blockgroup_lock) {
3223                 kfree(sbi);
3224                 goto out_free_orig;
3225         }
3226         sb->s_fs_info = sbi;
3227         sbi->s_sb = sb;
3228         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3229         sbi->s_sb_block = sb_block;
3230         if (sb->s_bdev->bd_part)
3231                 sbi->s_sectors_written_start =
3232                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3233
3234         /* Cleanup superblock name */
3235         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3236                 *cp = '!';
3237
3238         /* -EINVAL is default */
3239         ret = -EINVAL;
3240         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3241         if (!blocksize) {
3242                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3243                 goto out_fail;
3244         }
3245
3246         /*
3247          * The ext4 superblock will not be buffer aligned for other than 1kB
3248          * block sizes.  We need to calculate the offset from buffer start.
3249          */
3250         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3251                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3252                 offset = do_div(logical_sb_block, blocksize);
3253         } else {
3254                 logical_sb_block = sb_block;
3255         }
3256
3257         if (!(bh = sb_bread(sb, logical_sb_block))) {
3258                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3259                 goto out_fail;
3260         }
3261         /*
3262          * Note: s_es must be initialized as soon as possible because
3263          *       some ext4 macro-instructions depend on its value
3264          */
3265         es = (struct ext4_super_block *) (bh->b_data + offset);
3266         sbi->s_es = es;
3267         sb->s_magic = le16_to_cpu(es->s_magic);
3268         if (sb->s_magic != EXT4_SUPER_MAGIC)
3269                 goto cantfind_ext4;
3270         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3271
3272         /* Warn if metadata_csum and gdt_csum are both set. */
3273         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3274                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
3275             EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
3276                 ext4_warning(sb, KERN_INFO "metadata_csum and uninit_bg are "
3277                              "redundant flags; please run fsck.");
3278
3279         /* Check for a known checksum algorithm */
3280         if (!ext4_verify_csum_type(sb, es)) {
3281                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3282                          "unknown checksum algorithm.");
3283                 silent = 1;
3284                 goto cantfind_ext4;
3285         }
3286
3287         /* Load the checksum driver */
3288         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3289                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3290                 sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3291                 if (IS_ERR(sbi->s_chksum_driver)) {
3292                         ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3293                         ret = PTR_ERR(sbi->s_chksum_driver);
3294                         sbi->s_chksum_driver = NULL;
3295                         goto failed_mount;
3296                 }
3297         }
3298
3299         /* Check superblock checksum */
3300         if (!ext4_superblock_csum_verify(sb, es)) {
3301                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3302                          "invalid superblock checksum.  Run e2fsck?");
3303                 silent = 1;
3304                 goto cantfind_ext4;
3305         }
3306
3307         /* Precompute checksum seed for all metadata */
3308         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3309                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
3310                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3311                                                sizeof(es->s_uuid));
3312
3313         /* Set defaults before we parse the mount options */
3314         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3315         set_opt(sb, INIT_INODE_TABLE);
3316         if (def_mount_opts & EXT4_DEFM_DEBUG)
3317                 set_opt(sb, DEBUG);
3318         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3319                 set_opt(sb, GRPID);
3320         if (def_mount_opts & EXT4_DEFM_UID16)
3321                 set_opt(sb, NO_UID32);
3322         /* xattr user namespace & acls are now defaulted on */
3323         set_opt(sb, XATTR_USER);
3324 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3325         set_opt(sb, POSIX_ACL);
3326 #endif
3327         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3328                 set_opt(sb, JOURNAL_DATA);
3329         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3330                 set_opt(sb, ORDERED_DATA);
3331         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3332                 set_opt(sb, WRITEBACK_DATA);
3333
3334         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3335                 set_opt(sb, ERRORS_PANIC);
3336         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3337                 set_opt(sb, ERRORS_CONT);
3338         else
3339                 set_opt(sb, ERRORS_RO);
3340         if (def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY)
3341                 set_opt(sb, BLOCK_VALIDITY);
3342         if (def_mount_opts & EXT4_DEFM_DISCARD)
3343                 set_opt(sb, DISCARD);
3344
3345         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3346         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3347         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3348         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3349         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3350
3351         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3352                 set_opt(sb, BARRIER);
3353
3354         /*
3355          * enable delayed allocation by default
3356          * Use -o nodelalloc to turn it off
3357          */
3358         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3359             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3360                 set_opt(sb, DELALLOC);
3361
3362         /*
3363          * set default s_li_wait_mult for lazyinit, for the case there is
3364          * no mount option specified.
3365          */
3366         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3367
3368         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3369                            &journal_devnum, &journal_ioprio, 0)) {
3370                 ext4_msg(sb, KERN_WARNING,
3371                          "failed to parse options in superblock: %s",
3372                          sbi->s_es->s_mount_opts);
3373         }
3374         sbi->s_def_mount_opt = sbi->s_mount_opt;
3375         if (!parse_options((char *) data, sb, &journal_devnum,
3376                            &journal_ioprio, 0))
3377                 goto failed_mount;
3378
3379         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3380                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3381                             "with data=journal disables delayed "
3382                             "allocation and O_DIRECT support!\n");
3383                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3384                         ext4_msg(sb, KERN_ERR, "can't mount with "
3385                                  "both data=journal and delalloc");
3386                         goto failed_mount;
3387                 }
3388                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3389                         ext4_msg(sb, KERN_ERR, "can't mount with "
3390                                  "both data=journal and delalloc");
3391                         goto failed_mount;
3392                 }
3393                 if (test_opt(sb, DELALLOC))
3394                         clear_opt(sb, DELALLOC);
3395         }
3396
3397         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3398                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3399
3400         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3401             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3402              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3403              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3404                 ext4_msg(sb, KERN_WARNING,
3405                        "feature flags set on rev 0 fs, "
3406                        "running e2fsck is recommended");
3407
3408         if (IS_EXT2_SB(sb)) {
3409                 if (ext2_feature_set_ok(sb))
3410                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3411                                  "using the ext4 subsystem");
3412                 else {
3413                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3414                                  "to feature incompatibilities");
3415                         goto failed_mount;
3416                 }
3417         }
3418
3419         if (IS_EXT3_SB(sb)) {
3420                 if (ext3_feature_set_ok(sb))
3421                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3422                                  "using the ext4 subsystem");
3423                 else {
3424                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3425                                  "to feature incompatibilities");
3426                         goto failed_mount;
3427                 }
3428         }
3429
3430         /*
3431          * Check feature flags regardless of the revision level, since we
3432          * previously didn't change the revision level when setting the flags,
3433          * so there is a chance incompat flags are set on a rev 0 filesystem.
3434          */
3435         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3436                 goto failed_mount;
3437
3438         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3439         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3440             blocksize > EXT4_MAX_BLOCK_SIZE) {
3441                 ext4_msg(sb, KERN_ERR,
3442                        "Unsupported filesystem blocksize %d", blocksize);
3443                 goto failed_mount;
3444         }
3445
3446         if (sb->s_blocksize != blocksize) {
3447                 /* Validate the filesystem blocksize */
3448                 if (!sb_set_blocksize(sb, blocksize)) {
3449                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3450                                         blocksize);
3451                         goto failed_mount;
3452                 }
3453
3454                 brelse(bh);
3455                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3456                 offset = do_div(logical_sb_block, blocksize);
3457                 bh = sb_bread(sb, logical_sb_block);
3458                 if (!bh) {
3459                         ext4_msg(sb, KERN_ERR,
3460                                "Can't read superblock on 2nd try");
3461                         goto failed_mount;
3462                 }
3463                 es = (struct ext4_super_block *)(bh->b_data + offset);
3464                 sbi->s_es = es;
3465                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3466                         ext4_msg(sb, KERN_ERR,
3467                                "Magic mismatch, very weird!");
3468                         goto failed_mount;
3469                 }
3470         }
3471
3472         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3473                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3474         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3475                                                       has_huge_files);
3476         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3477
3478         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3479                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3480                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3481         } else {
3482                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3483                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3484                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3485                     (!is_power_of_2(sbi->s_inode_size)) ||
3486                     (sbi->s_inode_size > blocksize)) {
3487                         ext4_msg(sb, KERN_ERR,
3488                                "unsupported inode size: %d",
3489                                sbi->s_inode_size);
3490                         goto failed_mount;
3491                 }
3492                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3493                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3494         }
3495
3496         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3497         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3498                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3499                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3500                     !is_power_of_2(sbi->s_desc_size)) {
3501                         ext4_msg(sb, KERN_ERR,
3502                                "unsupported descriptor size %lu",
3503                                sbi->s_desc_size);
3504                         goto failed_mount;
3505                 }
3506         } else
3507                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3508
3509         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3510         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3511         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3512                 goto cantfind_ext4;
3513
3514         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3515         if (sbi->s_inodes_per_block == 0)
3516                 goto cantfind_ext4;
3517         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3518                                         sbi->s_inodes_per_block;
3519         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3520         sbi->s_sbh = bh;
3521         sbi->s_mount_state = le16_to_cpu(es->s_state);
3522         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3523         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3524
3525         for (i = 0; i < 4; i++)
3526                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3527         sbi->s_def_hash_version = es->s_def_hash_version;
3528         i = le32_to_cpu(es->s_flags);
3529         if (i & EXT2_FLAGS_UNSIGNED_HASH)
3530                 sbi->s_hash_unsigned = 3;
3531         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3532 #ifdef __CHAR_UNSIGNED__
3533                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3534                 sbi->s_hash_unsigned = 3;
3535 #else
3536                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3537 #endif
3538         }
3539
3540         /* Handle clustersize */
3541         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3542         has_bigalloc = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3543                                 EXT4_FEATURE_RO_COMPAT_BIGALLOC);
3544         if (has_bigalloc) {
3545                 if (clustersize < blocksize) {
3546                         ext4_msg(sb, KERN_ERR,
3547                                  "cluster size (%d) smaller than "
3548                                  "block size (%d)", clustersize, blocksize);
3549                         goto failed_mount;
3550                 }
3551                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3552                         le32_to_cpu(es->s_log_block_size);
3553                 sbi->s_clusters_per_group =
3554                         le32_to_cpu(es->s_clusters_per_group);
3555                 if (sbi->s_clusters_per_group > blocksize * 8) {
3556                         ext4_msg(sb, KERN_ERR,
3557                                  "#clusters per group too big: %lu",
3558                                  sbi->s_clusters_per_group);
3559                         goto failed_mount;
3560                 }
3561                 if (sbi->s_blocks_per_group !=
3562                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3563                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3564                                  "clusters per group (%lu) inconsistent",
3565                                  sbi->s_blocks_per_group,
3566                                  sbi->s_clusters_per_group);
3567                         goto failed_mount;
3568                 }
3569         } else {
3570                 if (clustersize != blocksize) {
3571                         ext4_warning(sb, "fragment/cluster size (%d) != "
3572                                      "block size (%d)", clustersize,
3573                                      blocksize);
3574                         clustersize = blocksize;
3575                 }
3576                 if (sbi->s_blocks_per_group > blocksize * 8) {
3577                         ext4_msg(sb, KERN_ERR,
3578                                  "#blocks per group too big: %lu",
3579                                  sbi->s_blocks_per_group);
3580                         goto failed_mount;
3581                 }
3582                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3583                 sbi->s_cluster_bits = 0;
3584         }
3585         sbi->s_cluster_ratio = clustersize / blocksize;
3586
3587         if (sbi->s_inodes_per_group > blocksize * 8) {
3588                 ext4_msg(sb, KERN_ERR,
3589                        "#inodes per group too big: %lu",
3590                        sbi->s_inodes_per_group);
3591                 goto failed_mount;
3592         }
3593
3594         /*
3595          * Test whether we have more sectors than will fit in sector_t,
3596          * and whether the max offset is addressable by the page cache.
3597          */
3598         err = generic_check_addressable(sb->s_blocksize_bits,
3599                                         ext4_blocks_count(es));
3600         if (err) {
3601                 ext4_msg(sb, KERN_ERR, "filesystem"
3602                          " too large to mount safely on this system");
3603                 if (sizeof(sector_t) < 8)
3604                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3605                 goto failed_mount;
3606         }
3607
3608         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3609                 goto cantfind_ext4;
3610
3611         /* check blocks count against device size */
3612         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3613         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3614                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3615                        "exceeds size of device (%llu blocks)",
3616                        ext4_blocks_count(es), blocks_count);
3617                 goto failed_mount;
3618         }
3619
3620         /*
3621          * It makes no sense for the first data block to be beyond the end
3622          * of the filesystem.
3623          */
3624         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3625                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3626                          "block %u is beyond end of filesystem (%llu)",
3627                          le32_to_cpu(es->s_first_data_block),
3628                          ext4_blocks_count(es));
3629                 goto failed_mount;
3630         }
3631         blocks_count = (ext4_blocks_count(es) -
3632                         le32_to_cpu(es->s_first_data_block) +
3633                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3634         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3635         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3636                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3637                        "(block count %llu, first data block %u, "
3638                        "blocks per group %lu)", sbi->s_groups_count,
3639                        ext4_blocks_count(es),
3640                        le32_to_cpu(es->s_first_data_block),
3641                        EXT4_BLOCKS_PER_GROUP(sb));
3642                 goto failed_mount;
3643         }
3644         sbi->s_groups_count = blocks_count;
3645         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3646                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3647         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3648                    EXT4_DESC_PER_BLOCK(sb);
3649         sbi->s_group_desc = ext4_kvmalloc(db_count *
3650                                           sizeof(struct buffer_head *),
3651                                           GFP_KERNEL);
3652         if (sbi->s_group_desc == NULL) {
3653                 ext4_msg(sb, KERN_ERR, "not enough memory");
3654                 ret = -ENOMEM;
3655                 goto failed_mount;
3656         }
3657
3658         if (ext4_proc_root)
3659                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
3660
3661         if (sbi->s_proc)
3662                 proc_create_data("options", S_IRUGO, sbi->s_proc,
3663                                  &ext4_seq_options_fops, sb);
3664
3665         bgl_lock_init(sbi->s_blockgroup_lock);
3666
3667         for (i = 0; i < db_count; i++) {
3668                 block = descriptor_loc(sb, logical_sb_block, i);
3669                 sbi->s_group_desc[i] = sb_bread(sb, block);
3670                 if (!sbi->s_group_desc[i]) {
3671                         ext4_msg(sb, KERN_ERR,
3672                                "can't read group descriptor %d", i);
3673                         db_count = i;
3674                         goto failed_mount2;
3675                 }
3676         }
3677         if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3678                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3679                 goto failed_mount2;
3680         }
3681         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
3682                 if (!ext4_fill_flex_info(sb)) {
3683                         ext4_msg(sb, KERN_ERR,
3684                                "unable to initialize "
3685                                "flex_bg meta info!");
3686                         goto failed_mount2;
3687                 }
3688
3689         sbi->s_gdb_count = db_count;
3690         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3691         spin_lock_init(&sbi->s_next_gen_lock);
3692
3693         init_timer(&sbi->s_err_report);
3694         sbi->s_err_report.function = print_daily_error_info;
3695         sbi->s_err_report.data = (unsigned long) sb;
3696
3697         err = percpu_counter_init(&sbi->s_freeclusters_counter,
3698                         ext4_count_free_clusters(sb));
3699         if (!err) {
3700                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
3701                                 ext4_count_free_inodes(sb));
3702         }
3703         if (!err) {
3704                 err = percpu_counter_init(&sbi->s_dirs_counter,
3705                                 ext4_count_dirs(sb));
3706         }
3707         if (!err) {
3708                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0);
3709         }
3710         if (!err) {
3711                 err = percpu_counter_init(&sbi->s_extent_cache_cnt, 0);
3712         }
3713         if (err) {
3714                 ext4_msg(sb, KERN_ERR, "insufficient memory");
3715                 goto failed_mount3;
3716         }
3717
3718         sbi->s_stripe = ext4_get_stripe_size(sbi);
3719         sbi->s_max_writeback_mb_bump = 128;
3720         sbi->s_extent_max_zeroout_kb = 32;
3721
3722         /* Register extent status tree shrinker */
3723         ext4_es_register_shrinker(sb);
3724
3725         /*
3726          * set up enough so that it can read an inode
3727          */
3728         if (!test_opt(sb, NOLOAD) &&
3729             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
3730                 sb->s_op = &ext4_sops;
3731         else
3732                 sb->s_op = &ext4_nojournal_sops;
3733         sb->s_export_op = &ext4_export_ops;
3734         sb->s_xattr = ext4_xattr_handlers;
3735 #ifdef CONFIG_QUOTA
3736         sb->dq_op = &ext4_quota_operations;
3737         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA))
3738                 sb->s_qcop = &ext4_qctl_sysfile_operations;
3739         else
3740                 sb->s_qcop = &ext4_qctl_operations;
3741 #endif
3742         memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
3743
3744         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
3745         mutex_init(&sbi->s_orphan_lock);
3746
3747         sb->s_root = NULL;
3748
3749         needs_recovery = (es->s_last_orphan != 0 ||
3750                           EXT4_HAS_INCOMPAT_FEATURE(sb,
3751                                     EXT4_FEATURE_INCOMPAT_RECOVER));
3752
3753         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) &&
3754             !(sb->s_flags & MS_RDONLY))
3755                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
3756                         goto failed_mount3;
3757
3758         /*
3759          * The first inode we look at is the journal inode.  Don't try
3760          * root first: it may be modified in the journal!
3761          */
3762         if (!test_opt(sb, NOLOAD) &&
3763             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3764                 if (ext4_load_journal(sb, es, journal_devnum))
3765                         goto failed_mount3;
3766         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
3767               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3768                 ext4_msg(sb, KERN_ERR, "required journal recovery "
3769                        "suppressed and not mounted read-only");
3770                 goto failed_mount_wq;
3771         } else {
3772                 clear_opt(sb, DATA_FLAGS);
3773                 sbi->s_journal = NULL;
3774                 needs_recovery = 0;
3775                 goto no_journal;
3776         }
3777
3778         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT) &&
3779             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
3780                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
3781                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
3782                 goto failed_mount_wq;
3783         }
3784
3785         if (!set_journal_csum_feature_set(sb)) {
3786                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
3787                          "feature set");
3788                 goto failed_mount_wq;
3789         }
3790
3791         /* We have now updated the journal if required, so we can
3792          * validate the data journaling mode. */
3793         switch (test_opt(sb, DATA_FLAGS)) {
3794         case 0:
3795                 /* No mode set, assume a default based on the journal
3796                  * capabilities: ORDERED_DATA if the journal can
3797                  * cope, else JOURNAL_DATA
3798                  */
3799                 if (jbd2_journal_check_available_features
3800                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
3801                         set_opt(sb, ORDERED_DATA);
3802                 else
3803                         set_opt(sb, JOURNAL_DATA);
3804                 break;
3805
3806         case EXT4_MOUNT_ORDERED_DATA:
3807         case EXT4_MOUNT_WRITEBACK_DATA:
3808                 if (!jbd2_journal_check_available_features
3809                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
3810                         ext4_msg(sb, KERN_ERR, "Journal does not support "
3811                                "requested data journaling mode");
3812                         goto failed_mount_wq;
3813                 }
3814         default:
3815                 break;
3816         }
3817         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3818
3819         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
3820
3821         /*
3822          * The journal may have updated the bg summary counts, so we
3823          * need to update the global counters.
3824          */
3825         percpu_counter_set(&sbi->s_freeclusters_counter,
3826                            ext4_count_free_clusters(sb));
3827         percpu_counter_set(&sbi->s_freeinodes_counter,
3828                            ext4_count_free_inodes(sb));
3829         percpu_counter_set(&sbi->s_dirs_counter,
3830                            ext4_count_dirs(sb));
3831         percpu_counter_set(&sbi->s_dirtyclusters_counter, 0);
3832
3833 no_journal:
3834         /*
3835          * Get the # of file system overhead blocks from the
3836          * superblock if present.
3837          */
3838         if (es->s_overhead_clusters)
3839                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
3840         else {
3841                 err = ext4_calculate_overhead(sb);
3842                 if (err)
3843                         goto failed_mount_wq;
3844         }
3845
3846         /*
3847          * The maximum number of concurrent works can be high and
3848          * concurrency isn't really necessary.  Limit it to 1.
3849          */
3850         EXT4_SB(sb)->dio_unwritten_wq =
3851                 alloc_workqueue("ext4-dio-unwritten", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
3852         if (!EXT4_SB(sb)->dio_unwritten_wq) {
3853                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
3854                 ret = -ENOMEM;
3855                 goto failed_mount_wq;
3856         }
3857
3858         /*
3859          * The jbd2_journal_load will have done any necessary log recovery,
3860          * so we can safely mount the rest of the filesystem now.
3861          */
3862
3863         root = ext4_iget(sb, EXT4_ROOT_INO);
3864         if (IS_ERR(root)) {
3865                 ext4_msg(sb, KERN_ERR, "get root inode failed");
3866                 ret = PTR_ERR(root);
3867                 root = NULL;
3868                 goto failed_mount4;
3869         }
3870         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
3871                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
3872                 iput(root);
3873                 goto failed_mount4;
3874         }
3875         sb->s_root = d_make_root(root);
3876         if (!sb->s_root) {
3877                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
3878                 ret = -ENOMEM;
3879                 goto failed_mount4;
3880         }
3881
3882         if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY))
3883                 sb->s_flags |= MS_RDONLY;
3884
3885         /* determine the minimum size of new large inodes, if present */
3886         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3887                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3888                                                      EXT4_GOOD_OLD_INODE_SIZE;
3889                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3890                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
3891                         if (sbi->s_want_extra_isize <
3892                             le16_to_cpu(es->s_want_extra_isize))
3893                                 sbi->s_want_extra_isize =
3894                                         le16_to_cpu(es->s_want_extra_isize);
3895                         if (sbi->s_want_extra_isize <
3896                             le16_to_cpu(es->s_min_extra_isize))
3897                                 sbi->s_want_extra_isize =
3898                                         le16_to_cpu(es->s_min_extra_isize);
3899                 }
3900         }
3901         /* Check if enough inode space is available */
3902         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3903                                                         sbi->s_inode_size) {
3904                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3905                                                        EXT4_GOOD_OLD_INODE_SIZE;
3906                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
3907                          "available");
3908         }
3909
3910         err = ext4_setup_system_zone(sb);
3911         if (err) {
3912                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
3913                          "zone (%d)", err);
3914                 goto failed_mount4a;
3915         }
3916
3917         ext4_ext_init(sb);
3918         err = ext4_mb_init(sb);
3919         if (err) {
3920                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
3921                          err);
3922                 goto failed_mount5;
3923         }
3924
3925         err = ext4_register_li_request(sb, first_not_zeroed);
3926         if (err)
3927                 goto failed_mount6;
3928
3929         sbi->s_kobj.kset = ext4_kset;
3930         init_completion(&sbi->s_kobj_unregister);
3931         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
3932                                    "%s", sb->s_id);
3933         if (err)
3934                 goto failed_mount7;
3935
3936 #ifdef CONFIG_QUOTA
3937         /* Enable quota usage during mount. */
3938         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
3939             !(sb->s_flags & MS_RDONLY)) {
3940                 err = ext4_enable_quotas(sb);
3941                 if (err)
3942                         goto failed_mount8;
3943         }
3944 #endif  /* CONFIG_QUOTA */
3945
3946         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
3947         ext4_orphan_cleanup(sb, es);
3948         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
3949         if (needs_recovery) {
3950                 ext4_msg(sb, KERN_INFO, "recovery complete");
3951                 ext4_mark_recovery_complete(sb, es);
3952         }
3953         if (EXT4_SB(sb)->s_journal) {
3954                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3955                         descr = " journalled data mode";
3956                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3957                         descr = " ordered data mode";
3958                 else
3959                         descr = " writeback data mode";
3960         } else
3961                 descr = "out journal";
3962
3963         if (test_opt(sb, DISCARD)) {
3964                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
3965                 if (!blk_queue_discard(q))
3966                         ext4_msg(sb, KERN_WARNING,
3967                                  "mounting with \"discard\" option, but "
3968                                  "the device does not support discard");
3969         }
3970
3971         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
3972                  "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
3973                  *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
3974
3975         if (es->s_error_count)
3976                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
3977
3978         kfree(orig_data);
3979         return 0;
3980
3981 cantfind_ext4:
3982         if (!silent)
3983                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
3984         goto failed_mount;
3985
3986 #ifdef CONFIG_QUOTA
3987 failed_mount8:
3988         kobject_del(&sbi->s_kobj);
3989 #endif
3990 failed_mount7:
3991         ext4_unregister_li_request(sb);
3992 failed_mount6:
3993         ext4_mb_release(sb);
3994 failed_mount5:
3995         ext4_ext_release(sb);
3996         ext4_release_system_zone(sb);
3997 failed_mount4a:
3998         dput(sb->s_root);
3999         sb->s_root = NULL;
4000 failed_mount4:
4001         ext4_msg(sb, KERN_ERR, "mount failed");
4002         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
4003 failed_mount_wq:
4004         if (sbi->s_journal) {
4005                 jbd2_journal_destroy(sbi->s_journal);
4006                 sbi->s_journal = NULL;
4007         }
4008 failed_mount3:
4009         del_timer(&sbi->s_err_report);
4010         if (sbi->s_flex_groups)
4011                 ext4_kvfree(sbi->s_flex_groups);
4012         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4013         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4014         percpu_counter_destroy(&sbi->s_dirs_counter);
4015         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4016         percpu_counter_destroy(&sbi->s_extent_cache_cnt);
4017         if (sbi->s_mmp_tsk)
4018                 kthread_stop(sbi->s_mmp_tsk);
4019 failed_mount2:
4020         for (i = 0; i < db_count; i++)
4021                 brelse(sbi->s_group_desc[i]);
4022         ext4_kvfree(sbi->s_group_desc);
4023 failed_mount:
4024         if (sbi->s_chksum_driver)
4025                 crypto_free_shash(sbi->s_chksum_driver);
4026         if (sbi->s_proc) {
4027                 remove_proc_entry("options", sbi->s_proc);
4028                 remove_proc_entry(sb->s_id, ext4_proc_root);
4029         }
4030 #ifdef CONFIG_QUOTA
4031         for (i = 0; i < MAXQUOTAS; i++)
4032                 kfree(sbi->s_qf_names[i]);
4033 #endif
4034         ext4_blkdev_remove(sbi);
4035         brelse(bh);
4036 out_fail:
4037         sb->s_fs_info = NULL;
4038         kfree(sbi->s_blockgroup_lock);
4039         kfree(sbi);
4040 out_free_orig:
4041         kfree(orig_data);
4042         return err ? err : ret;
4043 }
4044
4045 /*
4046  * Setup any per-fs journal parameters now.  We'll do this both on
4047  * initial mount, once the journal has been initialised but before we've
4048  * done any recovery; and again on any subsequent remount.
4049  */
4050 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4051 {
4052         struct ext4_sb_info *sbi = EXT4_SB(sb);
4053
4054         journal->j_commit_interval = sbi->s_commit_interval;
4055         journal->j_min_batch_time = sbi->s_min_batch_time;
4056         journal->j_max_batch_time = sbi->s_max_batch_time;
4057
4058         write_lock(&journal->j_state_lock);
4059         if (test_opt(sb, BARRIER))
4060                 journal->j_flags |= JBD2_BARRIER;
4061         else
4062                 journal->j_flags &= ~JBD2_BARRIER;
4063         if (test_opt(sb, DATA_ERR_ABORT))
4064                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4065         else
4066                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4067         write_unlock(&journal->j_state_lock);
4068 }
4069
4070 static journal_t *ext4_get_journal(struct super_block *sb,
4071                                    unsigned int journal_inum)
4072 {
4073         struct inode *journal_inode;
4074         journal_t *journal;
4075
4076         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4077
4078         /* First, test for the existence of a valid inode on disk.  Bad
4079          * things happen if we iget() an unused inode, as the subsequent
4080          * iput() will try to delete it. */
4081
4082         journal_inode = ext4_iget(sb, journal_inum);
4083         if (IS_ERR(journal_inode)) {
4084                 ext4_msg(sb, KERN_ERR, "no journal found");
4085                 return NULL;
4086         }
4087         if (!journal_inode->i_nlink) {
4088                 make_bad_inode(journal_inode);
4089                 iput(journal_inode);
4090                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4091                 return NULL;
4092         }
4093
4094         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4095                   journal_inode, journal_inode->i_size);
4096         if (!S_ISREG(journal_inode->i_mode)) {
4097                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4098                 iput(journal_inode);
4099                 return NULL;
4100         }
4101
4102         journal = jbd2_journal_init_inode(journal_inode);
4103         if (!journal) {
4104                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4105                 iput(journal_inode);
4106                 return NULL;
4107         }
4108         journal->j_private = sb;
4109         ext4_init_journal_params(sb, journal);
4110         return journal;
4111 }
4112
4113 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4114                                        dev_t j_dev)
4115 {
4116         struct buffer_head *bh;
4117         journal_t *journal;
4118         ext4_fsblk_t start;
4119         ext4_fsblk_t len;
4120         int hblock, blocksize;
4121         ext4_fsblk_t sb_block;
4122         unsigned long offset;
4123         struct ext4_super_block *es;
4124         struct block_device *bdev;
4125
4126         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4127
4128         bdev = ext4_blkdev_get(j_dev, sb);
4129         if (bdev == NULL)
4130                 return NULL;
4131
4132         blocksize = sb->s_blocksize;
4133         hblock = bdev_logical_block_size(bdev);
4134         if (blocksize < hblock) {
4135                 ext4_msg(sb, KERN_ERR,
4136                         "blocksize too small for journal device");
4137                 goto out_bdev;
4138         }
4139
4140         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4141         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4142         set_blocksize(bdev, blocksize);
4143         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4144                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4145                        "external journal");
4146                 goto out_bdev;
4147         }
4148
4149         es = (struct ext4_super_block *) (bh->b_data + offset);
4150         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4151             !(le32_to_cpu(es->s_feature_incompat) &
4152               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4153                 ext4_msg(sb, KERN_ERR, "external journal has "
4154                                         "bad superblock");
4155                 brelse(bh);
4156                 goto out_bdev;
4157         }
4158
4159         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4160                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4161                 brelse(bh);
4162                 goto out_bdev;
4163         }
4164
4165         len = ext4_blocks_count(es);
4166         start = sb_block + 1;
4167         brelse(bh);     /* we're done with the superblock */
4168
4169         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4170                                         start, len, blocksize);
4171         if (!journal) {
4172                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4173                 goto out_bdev;
4174         }
4175         journal->j_private = sb;
4176         ll_rw_block(READ, 1, &journal->j_sb_buffer);
4177         wait_on_buffer(journal->j_sb_buffer);
4178         if (!buffer_uptodate(journal->j_sb_buffer)) {
4179                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4180                 goto out_journal;
4181         }
4182         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4183                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4184                                         "user (unsupported) - %d",
4185                         be32_to_cpu(journal->j_superblock->s_nr_users));
4186                 goto out_journal;
4187         }
4188         EXT4_SB(sb)->journal_bdev = bdev;
4189         ext4_init_journal_params(sb, journal);
4190         return journal;
4191
4192 out_journal:
4193         jbd2_journal_destroy(journal);
4194 out_bdev:
4195         ext4_blkdev_put(bdev);
4196         return NULL;
4197 }
4198
4199 static int ext4_load_journal(struct super_block *sb,
4200                              struct ext4_super_block *es,
4201                              unsigned long journal_devnum)
4202 {
4203         journal_t *journal;
4204         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4205         dev_t journal_dev;
4206         int err = 0;
4207         int really_read_only;
4208
4209         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4210
4211         if (journal_devnum &&
4212             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4213                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4214                         "numbers have changed");
4215                 journal_dev = new_decode_dev(journal_devnum);
4216         } else
4217                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4218
4219         really_read_only = bdev_read_only(sb->s_bdev);
4220
4221         /*
4222          * Are we loading a blank journal or performing recovery after a
4223          * crash?  For recovery, we need to check in advance whether we
4224          * can get read-write access to the device.
4225          */
4226         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
4227                 if (sb->s_flags & MS_RDONLY) {
4228                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4229                                         "required on readonly filesystem");
4230                         if (really_read_only) {
4231                                 ext4_msg(sb, KERN_ERR, "write access "
4232                                         "unavailable, cannot proceed");
4233                                 return -EROFS;
4234                         }
4235                         ext4_msg(sb, KERN_INFO, "write access will "
4236                                "be enabled during recovery");
4237                 }
4238         }
4239
4240         if (journal_inum && journal_dev) {
4241                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4242                        "and inode journals!");
4243                 return -EINVAL;
4244         }
4245
4246         if (journal_inum) {
4247                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4248                         return -EINVAL;
4249         } else {
4250                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4251                         return -EINVAL;
4252         }
4253
4254         if (!(journal->j_flags & JBD2_BARRIER))
4255                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4256
4257         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
4258                 err = jbd2_journal_wipe(journal, !really_read_only);
4259         if (!err) {
4260                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4261                 if (save)
4262                         memcpy(save, ((char *) es) +
4263                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4264                 err = jbd2_journal_load(journal);
4265                 if (save)
4266                         memcpy(((char *) es) + EXT4_S_ERR_START,
4267                                save, EXT4_S_ERR_LEN);
4268                 kfree(save);
4269         }
4270
4271         if (err) {
4272                 ext4_msg(sb, KERN_ERR, "error loading journal");
4273                 jbd2_journal_destroy(journal);
4274                 return err;
4275         }
4276
4277         EXT4_SB(sb)->s_journal = journal;
4278         ext4_clear_journal_err(sb, es);
4279
4280         if (!really_read_only && journal_devnum &&
4281             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4282                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4283
4284                 /* Make sure we flush the recovery flag to disk. */
4285                 ext4_commit_super(sb, 1);
4286         }
4287
4288         return 0;
4289 }
4290
4291 static int ext4_commit_super(struct super_block *sb, int sync)
4292 {
4293         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4294         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4295         int error = 0;
4296
4297         if (!sbh || block_device_ejected(sb))
4298                 return error;
4299         if (buffer_write_io_error(sbh)) {
4300                 /*
4301                  * Oh, dear.  A previous attempt to write the
4302                  * superblock failed.  This could happen because the
4303                  * USB device was yanked out.  Or it could happen to
4304                  * be a transient write error and maybe the block will
4305                  * be remapped.  Nothing we can do but to retry the
4306                  * write and hope for the best.
4307                  */
4308                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4309                        "superblock detected");
4310                 clear_buffer_write_io_error(sbh);
4311                 set_buffer_uptodate(sbh);
4312         }
4313         /*
4314          * If the file system is mounted read-only, don't update the
4315          * superblock write time.  This avoids updating the superblock
4316          * write time when we are mounting the root file system
4317          * read/only but we need to replay the journal; at that point,
4318          * for people who are east of GMT and who make their clock
4319          * tick in localtime for Windows bug-for-bug compatibility,
4320          * the clock is set in the future, and this will cause e2fsck
4321          * to complain and force a full file system check.
4322          */
4323         if (!(sb->s_flags & MS_RDONLY))
4324                 es->s_wtime = cpu_to_le32(get_seconds());
4325         if (sb->s_bdev->bd_part)
4326                 es->s_kbytes_written =
4327                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4328                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4329                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4330         else
4331                 es->s_kbytes_written =
4332                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4333         ext4_free_blocks_count_set(es,
4334                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4335                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4336         es->s_free_inodes_count =
4337                 cpu_to_le32(percpu_counter_sum_positive(
4338                                 &EXT4_SB(sb)->s_freeinodes_counter));
4339         BUFFER_TRACE(sbh, "marking dirty");
4340         ext4_superblock_csum_set(sb);
4341         mark_buffer_dirty(sbh);
4342         if (sync) {
4343                 error = sync_dirty_buffer(sbh);
4344                 if (error)
4345                         return error;
4346
4347                 error = buffer_write_io_error(sbh);
4348                 if (error) {
4349                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4350                                "superblock");
4351                         clear_buffer_write_io_error(sbh);
4352                         set_buffer_uptodate(sbh);
4353                 }
4354         }
4355         return error;
4356 }
4357
4358 /*
4359  * Have we just finished recovery?  If so, and if we are mounting (or
4360  * remounting) the filesystem readonly, then we will end up with a
4361  * consistent fs on disk.  Record that fact.
4362  */
4363 static void ext4_mark_recovery_complete(struct super_block *sb,
4364                                         struct ext4_super_block *es)
4365 {
4366         journal_t *journal = EXT4_SB(sb)->s_journal;
4367
4368         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4369                 BUG_ON(journal != NULL);
4370                 return;
4371         }
4372         jbd2_journal_lock_updates(journal);
4373         if (jbd2_journal_flush(journal) < 0)
4374                 goto out;
4375
4376         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
4377             sb->s_flags & MS_RDONLY) {
4378                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4379                 ext4_commit_super(sb, 1);
4380         }
4381
4382 out:
4383         jbd2_journal_unlock_updates(journal);
4384 }
4385
4386 /*
4387  * If we are mounting (or read-write remounting) a filesystem whose journal
4388  * has recorded an error from a previous lifetime, move that error to the
4389  * main filesystem now.
4390  */
4391 static void ext4_clear_journal_err(struct super_block *sb,
4392                                    struct ext4_super_block *es)
4393 {
4394         journal_t *journal;
4395         int j_errno;
4396         const char *errstr;
4397
4398         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4399
4400         journal = EXT4_SB(sb)->s_journal;
4401
4402         /*
4403          * Now check for any error status which may have been recorded in the
4404          * journal by a prior ext4_error() or ext4_abort()
4405          */
4406
4407         j_errno = jbd2_journal_errno(journal);
4408         if (j_errno) {
4409                 char nbuf[16];
4410
4411                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4412                 ext4_warning(sb, "Filesystem error recorded "
4413                              "from previous mount: %s", errstr);
4414                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4415
4416                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4417                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4418                 ext4_commit_super(sb, 1);
4419
4420                 jbd2_journal_clear_err(journal);
4421                 jbd2_journal_update_sb_errno(journal);
4422         }
4423 }
4424
4425 /*
4426  * Force the running and committing transactions to commit,
4427  * and wait on the commit.
4428  */
4429 int ext4_force_commit(struct super_block *sb)
4430 {
4431         journal_t *journal;
4432
4433         if (sb->s_flags & MS_RDONLY)
4434                 return 0;
4435
4436         journal = EXT4_SB(sb)->s_journal;
4437         return ext4_journal_force_commit(journal);
4438 }
4439
4440 static int ext4_sync_fs(struct super_block *sb, int wait)
4441 {
4442         int ret = 0;
4443         tid_t target;
4444         struct ext4_sb_info *sbi = EXT4_SB(sb);
4445
4446         trace_ext4_sync_fs(sb, wait);
4447         flush_workqueue(sbi->dio_unwritten_wq);
4448         /*
4449          * Writeback quota in non-journalled quota case - journalled quota has
4450          * no dirty dquots
4451          */
4452         dquot_writeback_dquots(sb, -1);
4453         if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4454                 if (wait)
4455                         jbd2_log_wait_commit(sbi->s_journal, target);
4456         }
4457         return ret;
4458 }
4459
4460 /*
4461  * LVM calls this function before a (read-only) snapshot is created.  This
4462  * gives us a chance to flush the journal completely and mark the fs clean.
4463  *
4464  * Note that only this function cannot bring a filesystem to be in a clean
4465  * state independently. It relies on upper layer to stop all data & metadata
4466  * modifications.
4467  */
4468 static int ext4_freeze(struct super_block *sb)
4469 {
4470         int error = 0;
4471         journal_t *journal;
4472
4473         if (sb->s_flags & MS_RDONLY)
4474                 return 0;
4475
4476         journal = EXT4_SB(sb)->s_journal;
4477
4478         /* Now we set up the journal barrier. */
4479         jbd2_journal_lock_updates(journal);
4480
4481         /*
4482          * Don't clear the needs_recovery flag if we failed to flush
4483          * the journal.
4484          */
4485         error = jbd2_journal_flush(journal);
4486         if (error < 0)
4487                 goto out;
4488
4489         /* Journal blocked and flushed, clear needs_recovery flag. */
4490         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4491         error = ext4_commit_super(sb, 1);
4492 out:
4493         /* we rely on upper layer to stop further updates */
4494         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4495         return error;
4496 }
4497
4498 /*
4499  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4500  * flag here, even though the filesystem is not technically dirty yet.
4501  */
4502 static int ext4_unfreeze(struct super_block *sb)
4503 {
4504         if (sb->s_flags & MS_RDONLY)
4505                 return 0;
4506
4507         /* Reset the needs_recovery flag before the fs is unlocked. */
4508         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4509         ext4_commit_super(sb, 1);
4510         return 0;
4511 }
4512
4513 /*
4514  * Structure to save mount options for ext4_remount's benefit
4515  */
4516 struct ext4_mount_options {
4517         unsigned long s_mount_opt;
4518         unsigned long s_mount_opt2;
4519         kuid_t s_resuid;
4520         kgid_t s_resgid;
4521         unsigned long s_commit_interval;
4522         u32 s_min_batch_time, s_max_batch_time;
4523 #ifdef CONFIG_QUOTA
4524         int s_jquota_fmt;
4525         char *s_qf_names[MAXQUOTAS];
4526 #endif
4527 };
4528
4529 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4530 {
4531         struct ext4_super_block *es;
4532         struct ext4_sb_info *sbi = EXT4_SB(sb);
4533         unsigned long old_sb_flags;
4534         struct ext4_mount_options old_opts;
4535         int enable_quota = 0;
4536         ext4_group_t g;
4537         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4538         int err = 0;
4539 #ifdef CONFIG_QUOTA
4540         int i, j;
4541 #endif
4542         char *orig_data = kstrdup(data, GFP_KERNEL);
4543
4544         /* Store the original options */
4545         old_sb_flags = sb->s_flags;
4546         old_opts.s_mount_opt = sbi->s_mount_opt;
4547         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4548         old_opts.s_resuid = sbi->s_resuid;
4549         old_opts.s_resgid = sbi->s_resgid;
4550         old_opts.s_commit_interval = sbi->s_commit_interval;
4551         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4552         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4553 #ifdef CONFIG_QUOTA
4554         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4555         for (i = 0; i < MAXQUOTAS; i++)
4556                 if (sbi->s_qf_names[i]) {
4557                         old_opts.s_qf_names[i] = kstrdup(sbi->s_qf_names[i],
4558                                                          GFP_KERNEL);
4559                         if (!old_opts.s_qf_names[i]) {
4560                                 for (j = 0; j < i; j++)
4561                                         kfree(old_opts.s_qf_names[j]);
4562                                 kfree(orig_data);
4563                                 return -ENOMEM;
4564                         }
4565                 } else
4566                         old_opts.s_qf_names[i] = NULL;
4567 #endif
4568         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4569                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4570
4571         /*
4572          * Allow the "check" option to be passed as a remount option.
4573          */
4574         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
4575                 err = -EINVAL;
4576                 goto restore_opts;
4577         }
4578
4579         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4580                 ext4_abort(sb, "Abort forced by user");
4581
4582         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
4583                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
4584
4585         es = sbi->s_es;
4586
4587         if (sbi->s_journal) {
4588                 ext4_init_journal_params(sb, sbi->s_journal);
4589                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4590         }
4591
4592         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY)) {
4593                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
4594                         err = -EROFS;
4595                         goto restore_opts;
4596                 }
4597
4598                 if (*flags & MS_RDONLY) {
4599                         err = dquot_suspend(sb, -1);
4600                         if (err < 0)
4601                                 goto restore_opts;
4602
4603                         /*
4604                          * First of all, the unconditional stuff we have to do
4605                          * to disable replay of the journal when we next remount
4606                          */
4607                         sb->s_flags |= MS_RDONLY;
4608
4609                         /*
4610                          * OK, test if we are remounting a valid rw partition
4611                          * readonly, and if so set the rdonly flag and then
4612                          * mark the partition as valid again.
4613                          */
4614                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
4615                             (sbi->s_mount_state & EXT4_VALID_FS))
4616                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
4617
4618                         if (sbi->s_journal)
4619                                 ext4_mark_recovery_complete(sb, es);
4620                 } else {
4621                         /* Make sure we can mount this feature set readwrite */
4622                         if (!ext4_feature_set_ok(sb, 0)) {
4623                                 err = -EROFS;
4624                                 goto restore_opts;
4625                         }
4626                         /*
4627                          * Make sure the group descriptor checksums
4628                          * are sane.  If they aren't, refuse to remount r/w.
4629                          */
4630                         for (g = 0; g < sbi->s_groups_count; g++) {
4631                                 struct ext4_group_desc *gdp =
4632                                         ext4_get_group_desc(sb, g, NULL);
4633
4634                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
4635                                         ext4_msg(sb, KERN_ERR,
4636                "ext4_remount: Checksum for group %u failed (%u!=%u)",
4637                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
4638                                                le16_to_cpu(gdp->bg_checksum));
4639                                         err = -EINVAL;
4640                                         goto restore_opts;
4641                                 }
4642                         }
4643
4644                         /*
4645                          * If we have an unprocessed orphan list hanging
4646                          * around from a previously readonly bdev mount,
4647                          * require a full umount/remount for now.
4648                          */
4649                         if (es->s_last_orphan) {
4650                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
4651                                        "remount RDWR because of unprocessed "
4652                                        "orphan inode list.  Please "
4653                                        "umount/remount instead");
4654                                 err = -EINVAL;
4655                                 goto restore_opts;
4656                         }
4657
4658                         /*
4659                          * Mounting a RDONLY partition read-write, so reread
4660                          * and store the current valid flag.  (It may have
4661                          * been changed by e2fsck since we originally mounted
4662                          * the partition.)
4663                          */
4664                         if (sbi->s_journal)
4665                                 ext4_clear_journal_err(sb, es);
4666                         sbi->s_mount_state = le16_to_cpu(es->s_state);
4667                         if (!ext4_setup_super(sb, es, 0))
4668                                 sb->s_flags &= ~MS_RDONLY;
4669                         if (EXT4_HAS_INCOMPAT_FEATURE(sb,
4670                                                      EXT4_FEATURE_INCOMPAT_MMP))
4671                                 if (ext4_multi_mount_protect(sb,
4672                                                 le64_to_cpu(es->s_mmp_block))) {
4673                                         err = -EROFS;
4674                                         goto restore_opts;
4675                                 }
4676                         enable_quota = 1;
4677                 }
4678         }
4679
4680         /*
4681          * Reinitialize lazy itable initialization thread based on
4682          * current settings
4683          */
4684         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
4685                 ext4_unregister_li_request(sb);
4686         else {
4687                 ext4_group_t first_not_zeroed;
4688                 first_not_zeroed = ext4_has_uninit_itable(sb);
4689                 ext4_register_li_request(sb, first_not_zeroed);
4690         }
4691
4692         ext4_setup_system_zone(sb);
4693         if (sbi->s_journal == NULL && !(old_sb_flags & MS_RDONLY))
4694                 ext4_commit_super(sb, 1);
4695
4696 #ifdef CONFIG_QUOTA
4697         /* Release old quota file names */
4698         for (i = 0; i < MAXQUOTAS; i++)
4699                 kfree(old_opts.s_qf_names[i]);
4700         if (enable_quota) {
4701                 if (sb_any_quota_suspended(sb))
4702                         dquot_resume(sb, -1);
4703                 else if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
4704                                         EXT4_FEATURE_RO_COMPAT_QUOTA)) {
4705                         err = ext4_enable_quotas(sb);
4706                         if (err)
4707                                 goto restore_opts;
4708                 }
4709         }
4710 #endif
4711
4712         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
4713         kfree(orig_data);
4714         return 0;
4715
4716 restore_opts:
4717         sb->s_flags = old_sb_flags;
4718         sbi->s_mount_opt = old_opts.s_mount_opt;
4719         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
4720         sbi->s_resuid = old_opts.s_resuid;
4721         sbi->s_resgid = old_opts.s_resgid;
4722         sbi->s_commit_interval = old_opts.s_commit_interval;
4723         sbi->s_min_batch_time = old_opts.s_min_batch_time;
4724         sbi->s_max_batch_time = old_opts.s_max_batch_time;
4725 #ifdef CONFIG_QUOTA
4726         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
4727         for (i = 0; i < MAXQUOTAS; i++) {
4728                 kfree(sbi->s_qf_names[i]);
4729                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
4730         }
4731 #endif
4732         kfree(orig_data);
4733         return err;
4734 }
4735
4736 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
4737 {
4738         struct super_block *sb = dentry->d_sb;
4739         struct ext4_sb_info *sbi = EXT4_SB(sb);
4740         struct ext4_super_block *es = sbi->s_es;
4741         ext4_fsblk_t overhead = 0;
4742         u64 fsid;
4743         s64 bfree;
4744
4745         if (!test_opt(sb, MINIX_DF))
4746                 overhead = sbi->s_overhead;
4747
4748         buf->f_type = EXT4_SUPER_MAGIC;
4749         buf->f_bsize = sb->s_blocksize;
4750         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
4751         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
4752                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
4753         /* prevent underflow in case that few free space is available */
4754         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
4755         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
4756         if (buf->f_bfree < ext4_r_blocks_count(es))
4757                 buf->f_bavail = 0;
4758         buf->f_files = le32_to_cpu(es->s_inodes_count);
4759         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
4760         buf->f_namelen = EXT4_NAME_LEN;
4761         fsid = le64_to_cpup((void *)es->s_uuid) ^
4762                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
4763         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
4764         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
4765
4766         return 0;
4767 }
4768
4769 /* Helper function for writing quotas on sync - we need to start transaction
4770  * before quota file is locked for write. Otherwise the are possible deadlocks:
4771  * Process 1                         Process 2
4772  * ext4_create()                     quota_sync()
4773  *   jbd2_journal_start()                  write_dquot()
4774  *   dquot_initialize()                         down(dqio_mutex)
4775  *     down(dqio_mutex)                    jbd2_journal_start()
4776  *
4777  */
4778
4779 #ifdef CONFIG_QUOTA
4780
4781 static inline struct inode *dquot_to_inode(struct dquot *dquot)
4782 {
4783         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
4784 }
4785
4786 static int ext4_write_dquot(struct dquot *dquot)
4787 {
4788         int ret, err;
4789         handle_t *handle;
4790         struct inode *inode;
4791
4792         inode = dquot_to_inode(dquot);
4793         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
4794                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
4795         if (IS_ERR(handle))
4796                 return PTR_ERR(handle);
4797         ret = dquot_commit(dquot);
4798         err = ext4_journal_stop(handle);
4799         if (!ret)
4800                 ret = err;
4801         return ret;
4802 }
4803
4804 static int ext4_acquire_dquot(struct dquot *dquot)
4805 {
4806         int ret, err;
4807         handle_t *handle;
4808
4809         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
4810                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
4811         if (IS_ERR(handle))
4812                 return PTR_ERR(handle);
4813         ret = dquot_acquire(dquot);
4814         err = ext4_journal_stop(handle);
4815         if (!ret)
4816                 ret = err;
4817         return ret;
4818 }
4819
4820 static int ext4_release_dquot(struct dquot *dquot)
4821 {
4822         int ret, err;
4823         handle_t *handle;
4824
4825         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
4826                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
4827         if (IS_ERR(handle)) {
4828                 /* Release dquot anyway to avoid endless cycle in dqput() */
4829                 dquot_release(dquot);
4830                 return PTR_ERR(handle);
4831         }
4832         ret = dquot_release(dquot);
4833         err = ext4_journal_stop(handle);
4834         if (!ret)
4835                 ret = err;
4836         return ret;
4837 }
4838
4839 static int ext4_mark_dquot_dirty(struct dquot *dquot)
4840 {
4841         struct super_block *sb = dquot->dq_sb;
4842         struct ext4_sb_info *sbi = EXT4_SB(sb);
4843
4844         /* Are we journaling quotas? */
4845         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) ||
4846             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
4847                 dquot_mark_dquot_dirty(dquot);
4848                 return ext4_write_dquot(dquot);
4849         } else {
4850                 return dquot_mark_dquot_dirty(dquot);
4851         }
4852 }
4853
4854 static int ext4_write_info(struct super_block *sb, int type)
4855 {
4856         int ret, err;
4857         handle_t *handle;
4858
4859         /* Data block + inode block */
4860         handle = ext4_journal_start(sb->s_root->d_inode, EXT4_HT_QUOTA, 2);
4861         if (IS_ERR(handle))
4862                 return PTR_ERR(handle);
4863         ret = dquot_commit_info(sb, type);
4864         err = ext4_journal_stop(handle);
4865         if (!ret)
4866                 ret = err;
4867         return ret;
4868 }
4869
4870 /*
4871  * Turn on quotas during mount time - we need to find
4872  * the quota file and such...
4873  */
4874 static int ext4_quota_on_mount(struct super_block *sb, int type)
4875 {
4876         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
4877                                         EXT4_SB(sb)->s_jquota_fmt, type);
4878 }
4879
4880 /*
4881  * Standard function to be called on quota_on
4882  */
4883 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
4884                          struct path *path)
4885 {
4886         int err;
4887
4888         if (!test_opt(sb, QUOTA))
4889                 return -EINVAL;
4890
4891         /* Quotafile not on the same filesystem? */
4892         if (path->dentry->d_sb != sb)
4893                 return -EXDEV;
4894         /* Journaling quota? */
4895         if (EXT4_SB(sb)->s_qf_names[type]) {
4896                 /* Quotafile not in fs root? */
4897                 if (path->dentry->d_parent != sb->s_root)
4898                         ext4_msg(sb, KERN_WARNING,
4899                                 "Quota file not on filesystem root. "
4900                                 "Journaled quota will not work");
4901         }
4902
4903         /*
4904          * When we journal data on quota file, we have to flush journal to see
4905          * all updates to the file when we bypass pagecache...
4906          */
4907         if (EXT4_SB(sb)->s_journal &&
4908             ext4_should_journal_data(path->dentry->d_inode)) {
4909                 /*
4910                  * We don't need to lock updates but journal_flush() could
4911                  * otherwise be livelocked...
4912                  */
4913                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
4914                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
4915                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4916                 if (err)
4917                         return err;
4918         }
4919
4920         return dquot_quota_on(sb, type, format_id, path);
4921 }
4922
4923 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
4924                              unsigned int flags)
4925 {
4926         int err;
4927         struct inode *qf_inode;
4928         unsigned long qf_inums[MAXQUOTAS] = {
4929                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
4930                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
4931         };
4932
4933         BUG_ON(!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA));
4934
4935         if (!qf_inums[type])
4936                 return -EPERM;
4937
4938         qf_inode = ext4_iget(sb, qf_inums[type]);
4939         if (IS_ERR(qf_inode)) {
4940                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
4941                 return PTR_ERR(qf_inode);
4942         }
4943
4944         err = dquot_enable(qf_inode, type, format_id, flags);
4945         iput(qf_inode);
4946
4947         return err;
4948 }
4949
4950 /* Enable usage tracking for all quota types. */
4951 static int ext4_enable_quotas(struct super_block *sb)
4952 {
4953         int type, err = 0;
4954         unsigned long qf_inums[MAXQUOTAS] = {
4955                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
4956                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
4957         };
4958
4959         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
4960         for (type = 0; type < MAXQUOTAS; type++) {
4961                 if (qf_inums[type]) {
4962                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
4963                                                 DQUOT_USAGE_ENABLED);
4964                         if (err) {
4965                                 ext4_warning(sb,
4966                                         "Failed to enable quota tracking "
4967                                         "(type=%d, err=%d). Please run "
4968                                         "e2fsck to fix.", type, err);
4969                                 return err;
4970                         }
4971                 }
4972         }
4973         return 0;
4974 }
4975
4976 /*
4977  * quota_on function that is used when QUOTA feature is set.
4978  */
4979 static int ext4_quota_on_sysfile(struct super_block *sb, int type,
4980                                  int format_id)
4981 {
4982         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA))
4983                 return -EINVAL;
4984
4985         /*
4986          * USAGE was enabled at mount time. Only need to enable LIMITS now.
4987          */
4988         return ext4_quota_enable(sb, type, format_id, DQUOT_LIMITS_ENABLED);
4989 }
4990
4991 static int ext4_quota_off(struct super_block *sb, int type)
4992 {
4993         struct inode *inode = sb_dqopt(sb)->files[type];
4994         handle_t *handle;
4995
4996         /* Force all delayed allocation blocks to be allocated.
4997          * Caller already holds s_umount sem */
4998         if (test_opt(sb, DELALLOC))
4999                 sync_filesystem(sb);
5000
5001         if (!inode)
5002                 goto out;
5003
5004         /* Update modification times of quota files when userspace can
5005          * start looking at them */
5006         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5007         if (IS_ERR(handle))
5008                 goto out;
5009         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
5010         ext4_mark_inode_dirty(handle, inode);
5011         ext4_journal_stop(handle);
5012
5013 out:
5014         return dquot_quota_off(sb, type);
5015 }
5016
5017 /*
5018  * quota_off function that is used when QUOTA feature is set.
5019  */
5020 static int ext4_quota_off_sysfile(struct super_block *sb, int type)
5021 {
5022         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA))
5023                 return -EINVAL;
5024
5025         /* Disable only the limits. */
5026         return dquot_disable(sb, type, DQUOT_LIMITS_ENABLED);
5027 }
5028
5029 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5030  * acquiring the locks... As quota files are never truncated and quota code
5031  * itself serializes the operations (and no one else should touch the files)
5032  * we don't have to be afraid of races */
5033 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5034                                size_t len, loff_t off)
5035 {
5036         struct inode *inode = sb_dqopt(sb)->files[type];
5037         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5038         int err = 0;
5039         int offset = off & (sb->s_blocksize - 1);
5040         int tocopy;
5041         size_t toread;
5042         struct buffer_head *bh;
5043         loff_t i_size = i_size_read(inode);
5044
5045         if (off > i_size)
5046                 return 0;
5047         if (off+len > i_size)
5048                 len = i_size-off;
5049         toread = len;
5050         while (toread > 0) {
5051                 tocopy = sb->s_blocksize - offset < toread ?
5052                                 sb->s_blocksize - offset : toread;
5053                 bh = ext4_bread(NULL, inode, blk, 0, &err);
5054                 if (err)
5055                         return err;
5056                 if (!bh)        /* A hole? */
5057                         memset(data, 0, tocopy);
5058                 else
5059                         memcpy(data, bh->b_data+offset, tocopy);
5060                 brelse(bh);
5061                 offset = 0;
5062                 toread -= tocopy;
5063                 data += tocopy;
5064                 blk++;
5065         }
5066         return len;
5067 }
5068
5069 /* Write to quotafile (we know the transaction is already started and has
5070  * enough credits) */
5071 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5072                                 const char *data, size_t len, loff_t off)
5073 {
5074         struct inode *inode = sb_dqopt(sb)->files[type];
5075         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5076         int err = 0;
5077         int offset = off & (sb->s_blocksize - 1);
5078         struct buffer_head *bh;
5079         handle_t *handle = journal_current_handle();
5080
5081         if (EXT4_SB(sb)->s_journal && !handle) {
5082                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5083                         " cancelled because transaction is not started",
5084                         (unsigned long long)off, (unsigned long long)len);
5085                 return -EIO;
5086         }
5087         /*
5088          * Since we account only one data block in transaction credits,
5089          * then it is impossible to cross a block boundary.
5090          */
5091         if (sb->s_blocksize - offset < len) {
5092                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5093                         " cancelled because not block aligned",
5094                         (unsigned long long)off, (unsigned long long)len);
5095                 return -EIO;
5096         }
5097
5098         bh = ext4_bread(handle, inode, blk, 1, &err);
5099         if (!bh)
5100                 goto out;
5101         err = ext4_journal_get_write_access(handle, bh);
5102         if (err) {
5103                 brelse(bh);
5104                 goto out;
5105         }
5106         lock_buffer(bh);
5107         memcpy(bh->b_data+offset, data, len);
5108         flush_dcache_page(bh->b_page);
5109         unlock_buffer(bh);
5110         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5111         brelse(bh);
5112 out:
5113         if (err)
5114                 return err;
5115         if (inode->i_size < off + len) {
5116                 i_size_write(inode, off + len);
5117                 EXT4_I(inode)->i_disksize = inode->i_size;
5118                 ext4_mark_inode_dirty(handle, inode);
5119         }
5120         return len;
5121 }
5122
5123 #endif
5124
5125 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5126                        const char *dev_name, void *data)
5127 {
5128         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5129 }
5130
5131 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5132 static inline void register_as_ext2(void)
5133 {
5134         int err = register_filesystem(&ext2_fs_type);
5135         if (err)
5136                 printk(KERN_WARNING
5137                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5138 }
5139
5140 static inline void unregister_as_ext2(void)
5141 {
5142         unregister_filesystem(&ext2_fs_type);
5143 }
5144
5145 static inline int ext2_feature_set_ok(struct super_block *sb)
5146 {
5147         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))
5148                 return 0;
5149         if (sb->s_flags & MS_RDONLY)
5150                 return 1;
5151         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))
5152                 return 0;
5153         return 1;
5154 }
5155 MODULE_ALIAS("ext2");
5156 #else
5157 static inline void register_as_ext2(void) { }
5158 static inline void unregister_as_ext2(void) { }
5159 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5160 #endif
5161
5162 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5163 static inline void register_as_ext3(void)
5164 {
5165         int err = register_filesystem(&ext3_fs_type);
5166         if (err)
5167                 printk(KERN_WARNING
5168                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5169 }
5170
5171 static inline void unregister_as_ext3(void)
5172 {
5173         unregister_filesystem(&ext3_fs_type);
5174 }
5175
5176 static inline int ext3_feature_set_ok(struct super_block *sb)
5177 {
5178         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT3_FEATURE_INCOMPAT_SUPP))
5179                 return 0;
5180         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
5181                 return 0;
5182         if (sb->s_flags & MS_RDONLY)
5183                 return 1;
5184         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT3_FEATURE_RO_COMPAT_SUPP))
5185                 return 0;
5186         return 1;
5187 }
5188 MODULE_ALIAS("ext3");
5189 #else
5190 static inline void register_as_ext3(void) { }
5191 static inline void unregister_as_ext3(void) { }
5192 static inline int ext3_feature_set_ok(struct super_block *sb) { return 0; }
5193 #endif
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
5203 static int __init ext4_init_feat_adverts(void)
5204 {
5205         struct ext4_features *ef;
5206         int ret = -ENOMEM;
5207
5208         ef = kzalloc(sizeof(struct ext4_features), GFP_KERNEL);
5209         if (!ef)
5210                 goto out;
5211
5212         ef->f_kobj.kset = ext4_kset;
5213         init_completion(&ef->f_kobj_unregister);
5214         ret = kobject_init_and_add(&ef->f_kobj, &ext4_feat_ktype, NULL,
5215                                    "features");
5216         if (ret) {
5217                 kfree(ef);
5218                 goto out;
5219         }
5220
5221         ext4_feat = ef;
5222         ret = 0;
5223 out:
5224         return ret;
5225 }
5226
5227 static void ext4_exit_feat_adverts(void)
5228 {
5229         kobject_put(&ext4_feat->f_kobj);
5230         wait_for_completion(&ext4_feat->f_kobj_unregister);
5231         kfree(ext4_feat);
5232 }
5233
5234 /* Shared across all ext4 file systems */
5235 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5236 struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
5237
5238 static int __init ext4_init_fs(void)
5239 {
5240         int i, err;
5241
5242         ext4_li_info = NULL;
5243         mutex_init(&ext4_li_mtx);
5244
5245         /* Build-time check for flags consistency */
5246         ext4_check_flag_values();
5247
5248         for (i = 0; i < EXT4_WQ_HASH_SZ; i++) {
5249                 mutex_init(&ext4__aio_mutex[i]);
5250                 init_waitqueue_head(&ext4__ioend_wq[i]);
5251         }
5252
5253         err = ext4_init_es();
5254         if (err)
5255                 return err;
5256
5257         err = ext4_init_pageio();
5258         if (err)
5259                 goto out7;
5260
5261         err = ext4_init_system_zone();
5262         if (err)
5263                 goto out6;
5264         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
5265         if (!ext4_kset) {
5266                 err = -ENOMEM;
5267                 goto out5;
5268         }
5269         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
5270
5271         err = ext4_init_feat_adverts();
5272         if (err)
5273                 goto out4;
5274
5275         err = ext4_init_mballoc();
5276         if (err)
5277                 goto out3;
5278
5279         err = ext4_init_xattr();
5280         if (err)
5281                 goto out2;
5282         err = init_inodecache();
5283         if (err)
5284                 goto out1;
5285         register_as_ext3();
5286         register_as_ext2();
5287         err = register_filesystem(&ext4_fs_type);
5288         if (err)
5289                 goto out;
5290
5291         return 0;
5292 out:
5293         unregister_as_ext2();
5294         unregister_as_ext3();
5295         destroy_inodecache();
5296 out1:
5297         ext4_exit_xattr();
5298 out2:
5299         ext4_exit_mballoc();
5300 out3:
5301         ext4_exit_feat_adverts();
5302 out4:
5303         if (ext4_proc_root)
5304                 remove_proc_entry("fs/ext4", NULL);
5305         kset_unregister(ext4_kset);
5306 out5:
5307         ext4_exit_system_zone();
5308 out6:
5309         ext4_exit_pageio();
5310 out7:
5311         ext4_exit_es();
5312
5313         return err;
5314 }
5315
5316 static void __exit ext4_exit_fs(void)
5317 {
5318         ext4_destroy_lazyinit_thread();
5319         unregister_as_ext2();
5320         unregister_as_ext3();
5321         unregister_filesystem(&ext4_fs_type);
5322         destroy_inodecache();
5323         ext4_exit_xattr();
5324         ext4_exit_mballoc();
5325         ext4_exit_feat_adverts();
5326         remove_proc_entry("fs/ext4", NULL);
5327         kset_unregister(ext4_kset);
5328         ext4_exit_system_zone();
5329         ext4_exit_pageio();
5330 }
5331
5332 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5333 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5334 MODULE_LICENSE("GPL");
5335 module_init(ext4_init_fs)
5336 module_exit(ext4_exit_fs)