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/smp_lock.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/proc_fs.h>
  39 #include <linux/ctype.h>
  40 #include <linux/log2.h>
  41 #include <linux/crc16.h>
  42 #include <asm/uaccess.h>
  43
  44 #include "ext4.h"
  45 #include "ext4_jbd2.h"
  46 #include "xattr.h"
  47 #include "acl.h"
  48 #include "mballoc.h"
  49
  50 #define CREATE_TRACE_POINTS
  51 #include <trace/events/ext4.h>
  52
  53 struct proc_dir_entry *ext4_proc_root;
  54 static struct kset *ext4_kset;
  55
  56 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  57                              unsigned long journal_devnum);
  58 static int ext4_commit_super(struct super_block *sb, int sync);
  59 static void ext4_mark_recovery_complete(struct super_block *sb,
  60                                         struct ext4_super_block *es);
  61 static void ext4_clear_journal_err(struct super_block *sb,
  62                                    struct ext4_super_block *es);
  63 static int ext4_sync_fs(struct super_block *sb, int wait);
  64 static const char *ext4_decode_error(struct super_block *sb, int errno,
  65                                      char nbuf[16]);
  66 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  67 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  68 static int ext4_unfreeze(struct super_block *sb);
  69 static void ext4_write_super(struct super_block *sb);
  70 static int ext4_freeze(struct super_block *sb);
  71 static int ext4_get_sb(struct file_system_type *fs_type, int flags,
  72                        const char *dev_name, void *data, struct vfsmount *mnt);
  73
  74 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
  75 static struct file_system_type ext3_fs_type = {
  76         .owner          = THIS_MODULE,
  77         .name           = "ext3",
  78         .get_sb         = ext4_get_sb,
  79         .kill_sb        = kill_block_super,
  80         .fs_flags       = FS_REQUIRES_DEV,
  81 };
  82 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
  83 #else
  84 #define IS_EXT3_SB(sb) (0)
  85 #endif
  86
  87 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
  88                                struct ext4_group_desc *bg)
  89 {
  90         return le32_to_cpu(bg->bg_block_bitmap_lo) |
  91                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  92                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
  93 }
  94
  95 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
  96                                struct ext4_group_desc *bg)
  97 {
  98         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
  99                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 100                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 101 }
 102
 103 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 104                               struct ext4_group_desc *bg)
 105 {
 106         return le32_to_cpu(bg->bg_inode_table_lo) |
 107                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 108                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 109 }
 110
 111 __u32 ext4_free_blks_count(struct super_block *sb,
 112                               struct ext4_group_desc *bg)
 113 {
 114         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 115                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 116                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 117 }
 118
 119 __u32 ext4_free_inodes_count(struct super_block *sb,
 120                               struct ext4_group_desc *bg)
 121 {
 122         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 123                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 124                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 125 }
 126
 127 __u32 ext4_used_dirs_count(struct super_block *sb,
 128                               struct ext4_group_desc *bg)
 129 {
 130         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 131                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 132                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 133 }
 134
 135 __u32 ext4_itable_unused_count(struct super_block *sb,
 136                               struct ext4_group_desc *bg)
 137 {
 138         return le16_to_cpu(bg->bg_itable_unused_lo) |
 139                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 140                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 141 }
 142
 143 void ext4_block_bitmap_set(struct super_block *sb,
 144                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 145 {
 146         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 147         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 148                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 149 }
 150
 151 void ext4_inode_bitmap_set(struct super_block *sb,
 152                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 153 {
 154         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 155         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 156                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 157 }
 158
 159 void ext4_inode_table_set(struct super_block *sb,
 160                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 161 {
 162         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 163         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 164                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 165 }
 166
 167 void ext4_free_blks_set(struct super_block *sb,
 168                           struct ext4_group_desc *bg, __u32 count)
 169 {
 170         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 171         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 172                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 173 }
 174
 175 void ext4_free_inodes_set(struct super_block *sb,
 176                           struct ext4_group_desc *bg, __u32 count)
 177 {
 178         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 179         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 180                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 181 }
 182
 183 void ext4_used_dirs_set(struct super_block *sb,
 184                           struct ext4_group_desc *bg, __u32 count)
 185 {
 186         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 187         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 188                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 189 }
 190
 191 void ext4_itable_unused_set(struct super_block *sb,
 192                           struct ext4_group_desc *bg, __u32 count)
 193 {
 194         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 195         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 196                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 197 }
 198
 199
 200 /* Just increment the non-pointer handle value */
 201 static handle_t *ext4_get_nojournal(void)
 202 {
 203         handle_t *handle = current->journal_info;
 204         unsigned long ref_cnt = (unsigned long)handle;
 205
 206         BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
 207
 208         ref_cnt++;
 209         handle = (handle_t *)ref_cnt;
 210
 211         current->journal_info = handle;
 212         return handle;
 213 }
 214
 215
 216 /* Decrement the non-pointer handle value */
 217 static void ext4_put_nojournal(handle_t *handle)
 218 {
 219         unsigned long ref_cnt = (unsigned long)handle;
 220
 221         BUG_ON(ref_cnt == 0);
 222
 223         ref_cnt--;
 224         handle = (handle_t *)ref_cnt;
 225
 226         current->journal_info = handle;
 227 }
 228
 229 /*
 230  * Wrappers for jbd2_journal_start/end.
 231  *
 232  * The only special thing we need to do here is to make sure that all
 233  * journal_end calls result in the superblock being marked dirty, so
 234  * that sync() will call the filesystem's write_super callback if
 235  * appropriate.
 236  */
 237 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 238 {
 239         journal_t *journal;
 240
 241         if (sb->s_flags & MS_RDONLY)
 242                 return ERR_PTR(-EROFS);
 243
 244         vfs_check_frozen(sb, SB_FREEZE_WRITE);
 245         /* Special case here: if the journal has aborted behind our
 246          * backs (eg. EIO in the commit thread), then we still need to
 247          * take the FS itself readonly cleanly. */
 248         journal = EXT4_SB(sb)->s_journal;
 249         if (journal) {
 250                 if (is_journal_aborted(journal)) {
 251                         ext4_abort(sb, __func__, "Detected aborted journal");
 252                         return ERR_PTR(-EROFS);
 253                 }
 254                 return jbd2_journal_start(journal, nblocks);
 255         }
 256         return ext4_get_nojournal();
 257 }
 258
 259 /*
 260  * The only special thing we need to do here is to make sure that all
 261  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 262  * that sync() will call the filesystem's write_super callback if
 263  * appropriate.
 264  */
 265 int __ext4_journal_stop(const char *where, handle_t *handle)
 266 {
 267         struct super_block *sb;
 268         int err;
 269         int rc;
 270
 271         if (!ext4_handle_valid(handle)) {
 272                 ext4_put_nojournal(handle);
 273                 return 0;
 274         }
 275         sb = handle->h_transaction->t_journal->j_private;
 276         err = handle->h_err;
 277         rc = jbd2_journal_stop(handle);
 278
 279         if (!err)
 280                 err = rc;
 281         if (err)
 282                 __ext4_std_error(sb, where, err);
 283         return err;
 284 }
 285
 286 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
 287                 struct buffer_head *bh, handle_t *handle, int err)
 288 {
 289         char nbuf[16];
 290         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 291
 292         BUG_ON(!ext4_handle_valid(handle));
 293
 294         if (bh)
 295                 BUFFER_TRACE(bh, "abort");
 296
 297         if (!handle->h_err)
 298                 handle->h_err = err;
 299
 300         if (is_handle_aborted(handle))
 301                 return;
 302
 303         printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
 304                caller, errstr, err_fn);
 305
 306         jbd2_journal_abort_handle(handle);
 307 }
 308
 309 /* Deal with the reporting of failure conditions on a filesystem such as
 310  * inconsistencies detected or read IO failures.
 311  *
 312  * On ext2, we can store the error state of the filesystem in the
 313  * superblock.  That is not possible on ext4, because we may have other
 314  * write ordering constraints on the superblock which prevent us from
 315  * writing it out straight away; and given that the journal is about to
 316  * be aborted, we can't rely on the current, or future, transactions to
 317  * write out the superblock safely.
 318  *
 319  * We'll just use the jbd2_journal_abort() error code to record an error in
 320  * the journal instead.  On recovery, the journal will complain about
 321  * that error until we've noted it down and cleared it.
 322  */
 323
 324 static void ext4_handle_error(struct super_block *sb)
 325 {
 326         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 327
 328         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 329         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 330
 331         if (sb->s_flags & MS_RDONLY)
 332                 return;
 333
 334         if (!test_opt(sb, ERRORS_CONT)) {
 335                 journal_t *journal = EXT4_SB(sb)->s_journal;
 336
 337                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 338                 if (journal)
 339                         jbd2_journal_abort(journal, -EIO);
 340         }
 341         if (test_opt(sb, ERRORS_RO)) {
 342                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 343                 sb->s_flags |= MS_RDONLY;
 344         }
 345         ext4_commit_super(sb, 1);
 346         if (test_opt(sb, ERRORS_PANIC))
 347                 panic("EXT4-fs (device %s): panic forced after error\n",
 348                         sb->s_id);
 349 }
 350
 351 void __ext4_error(struct super_block *sb, const char *function,
 352                 const char *fmt, ...)
 353 {
 354         va_list args;
 355
 356         va_start(args, fmt);
 357         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 358         vprintk(fmt, args);
 359         printk("\n");
 360         va_end(args);
 361
 362         ext4_handle_error(sb);
 363 }
 364
 365 void ext4_error_inode(const char *function, struct inode *inode,
 366                       const char *fmt, ...)
 367 {
 368         va_list args;
 369
 370         va_start(args, fmt);
 371         printk(KERN_CRIT "EXT4-fs error (device %s): %s: inode #%lu: (comm %s) ",
 372                inode->i_sb->s_id, function, inode->i_ino, current->comm);
 373         vprintk(fmt, args);
 374         printk("\n");
 375         va_end(args);
 376
 377         ext4_handle_error(inode->i_sb);
 378 }
 379
 380 void ext4_error_file(const char *function, struct file *file,
 381                      const char *fmt, ...)
 382 {
 383         va_list args;
 384         struct inode *inode = file->f_dentry->d_inode;
 385         char pathname[80], *path;
 386
 387         va_start(args, fmt);
 388         path = d_path(&(file->f_path), pathname, sizeof(pathname));
 389         if (!path)
 390                 path = "(unknown)";
 391         printk(KERN_CRIT
 392                "EXT4-fs error (device %s): %s: inode #%lu (comm %s path %s): ",
 393                inode->i_sb->s_id, function, inode->i_ino, current->comm, path);
 394         vprintk(fmt, args);
 395         printk("\n");
 396         va_end(args);
 397
 398         ext4_handle_error(inode->i_sb);
 399 }
 400
 401 static const char *ext4_decode_error(struct super_block *sb, int errno,
 402                                      char nbuf[16])
 403 {
 404         char *errstr = NULL;
 405
 406         switch (errno) {
 407         case -EIO:
 408                 errstr = "IO failure";
 409                 break;
 410         case -ENOMEM:
 411                 errstr = "Out of memory";
 412                 break;
 413         case -EROFS:
 414                 if (!sb || (EXT4_SB(sb)->s_journal &&
 415                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 416                         errstr = "Journal has aborted";
 417                 else
 418                         errstr = "Readonly filesystem";
 419                 break;
 420         default:
 421                 /* If the caller passed in an extra buffer for unknown
 422                  * errors, textualise them now.  Else we just return
 423                  * NULL. */
 424                 if (nbuf) {
 425                         /* Check for truncated error codes... */
 426                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 427                                 errstr = nbuf;
 428                 }
 429                 break;
 430         }
 431
 432         return errstr;
 433 }
 434
 435 /* __ext4_std_error decodes expected errors from journaling functions
 436  * automatically and invokes the appropriate error response.  */
 437
 438 void __ext4_std_error(struct super_block *sb, const char *function, int errno)
 439 {
 440         char nbuf[16];
 441         const char *errstr;
 442
 443         /* Special case: if the error is EROFS, and we're not already
 444          * inside a transaction, then there's really no point in logging
 445          * an error. */
 446         if (errno == -EROFS && journal_current_handle() == NULL &&
 447             (sb->s_flags & MS_RDONLY))
 448                 return;
 449
 450         errstr = ext4_decode_error(sb, errno, nbuf);
 451         printk(KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
 452                sb->s_id, function, errstr);
 453
 454         ext4_handle_error(sb);
 455 }
 456
 457 /*
 458  * ext4_abort is a much stronger failure handler than ext4_error.  The
 459  * abort function may be used to deal with unrecoverable failures such
 460  * as journal IO errors or ENOMEM at a critical moment in log management.
 461  *
 462  * We unconditionally force the filesystem into an ABORT|READONLY state,
 463  * unless the error response on the fs has been set to panic in which
 464  * case we take the easy way out and panic immediately.
 465  */
 466
 467 void ext4_abort(struct super_block *sb, const char *function,
 468                 const char *fmt, ...)
 469 {
 470         va_list args;
 471
 472         va_start(args, fmt);
 473         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 474         vprintk(fmt, args);
 475         printk("\n");
 476         va_end(args);
 477
 478         if (test_opt(sb, ERRORS_PANIC))
 479                 panic("EXT4-fs panic from previous error\n");
 480
 481         if (sb->s_flags & MS_RDONLY)
 482                 return;
 483
 484         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 485         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 486         sb->s_flags |= MS_RDONLY;
 487         EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 488         if (EXT4_SB(sb)->s_journal)
 489                 jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 490 }
 491
 492 void ext4_msg (struct super_block * sb, const char *prefix,
 493                    const char *fmt, ...)
 494 {
 495         va_list args;
 496
 497         va_start(args, fmt);
 498         printk("%sEXT4-fs (%s): ", prefix, sb->s_id);
 499         vprintk(fmt, args);
 500         printk("\n");
 501         va_end(args);
 502 }
 503
 504 void __ext4_warning(struct super_block *sb, const char *function,
 505                   const char *fmt, ...)
 506 {
 507         va_list args;
 508
 509         va_start(args, fmt);
 510         printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
 511                sb->s_id, function);
 512         vprintk(fmt, args);
 513         printk("\n");
 514         va_end(args);
 515 }
 516
 517 void ext4_grp_locked_error(struct super_block *sb, ext4_group_t grp,
 518                            const char *function, const char *fmt, ...)
 519 __releases(bitlock)
 520 __acquires(bitlock)
 521 {
 522         va_list args;
 523         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 524
 525         va_start(args, fmt);
 526         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 527         vprintk(fmt, args);
 528         printk("\n");
 529         va_end(args);
 530
 531         if (test_opt(sb, ERRORS_CONT)) {
 532                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 533                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 534                 ext4_commit_super(sb, 0);
 535                 return;
 536         }
 537         ext4_unlock_group(sb, grp);
 538         ext4_handle_error(sb);
 539         /*
 540          * We only get here in the ERRORS_RO case; relocking the group
 541          * may be dangerous, but nothing bad will happen since the
 542          * filesystem will have already been marked read/only and the
 543          * journal has been aborted.  We return 1 as a hint to callers
 544          * who might what to use the return value from
 545          * ext4_grp_locked_error() to distinguish beween the
 546          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 547          * aggressively from the ext4 function in question, with a
 548          * more appropriate error code.
 549          */
 550         ext4_lock_group(sb, grp);
 551         return;
 552 }
 553
 554 void ext4_update_dynamic_rev(struct super_block *sb)
 555 {
 556         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 557
 558         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 559                 return;
 560
 561         ext4_warning(sb,
 562                      "updating to rev %d because of new feature flag, "
 563                      "running e2fsck is recommended",
 564                      EXT4_DYNAMIC_REV);
 565
 566         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 567         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 568         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 569         /* leave es->s_feature_*compat flags alone */
 570         /* es->s_uuid will be set by e2fsck if empty */
 571
 572         /*
 573          * The rest of the superblock fields should be zero, and if not it
 574          * means they are likely already in use, so leave them alone.  We
 575          * can leave it up to e2fsck to clean up any inconsistencies there.
 576          */
 577 }
 578
 579 /*
 580  * Open the external journal device
 581  */
 582 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 583 {
 584         struct block_device *bdev;
 585         char b[BDEVNAME_SIZE];
 586
 587         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
 588         if (IS_ERR(bdev))
 589                 goto fail;
 590         return bdev;
 591
 592 fail:
 593         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 594                         __bdevname(dev, b), PTR_ERR(bdev));
 595         return NULL;
 596 }
 597
 598 /*
 599  * Release the journal device
 600  */
 601 static int ext4_blkdev_put(struct block_device *bdev)
 602 {
 603         bd_release(bdev);
 604         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
 605 }
 606
 607 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 608 {
 609         struct block_device *bdev;
 610         int ret = -ENODEV;
 611
 612         bdev = sbi->journal_bdev;
 613         if (bdev) {
 614                 ret = ext4_blkdev_put(bdev);
 615                 sbi->journal_bdev = NULL;
 616         }
 617         return ret;
 618 }
 619
 620 static inline struct inode *orphan_list_entry(struct list_head *l)
 621 {
 622         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 623 }
 624
 625 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 626 {
 627         struct list_head *l;
 628
 629         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 630                  le32_to_cpu(sbi->s_es->s_last_orphan));
 631
 632         printk(KERN_ERR "sb_info orphan list:\n");
 633         list_for_each(l, &sbi->s_orphan) {
 634                 struct inode *inode = orphan_list_entry(l);
 635                 printk(KERN_ERR "  "
 636                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 637                        inode->i_sb->s_id, inode->i_ino, inode,
 638                        inode->i_mode, inode->i_nlink,
 639                        NEXT_ORPHAN(inode));
 640         }
 641 }
 642
 643 static void ext4_put_super(struct super_block *sb)
 644 {
 645         struct ext4_sb_info *sbi = EXT4_SB(sb);
 646         struct ext4_super_block *es = sbi->s_es;
 647         int i, err;
 648
 649         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 650
 651         flush_workqueue(sbi->dio_unwritten_wq);
 652         destroy_workqueue(sbi->dio_unwritten_wq);
 653
 654         lock_super(sb);
 655         lock_kernel();
 656         if (sb->s_dirt)
 657                 ext4_commit_super(sb, 1);
 658
 659         if (sbi->s_journal) {
 660                 err = jbd2_journal_destroy(sbi->s_journal);
 661                 sbi->s_journal = NULL;
 662                 if (err < 0)
 663                         ext4_abort(sb, __func__,
 664                                    "Couldn't clean up the journal");
 665         }
 666
 667         ext4_release_system_zone(sb);
 668         ext4_mb_release(sb);
 669         ext4_ext_release(sb);
 670         ext4_xattr_put_super(sb);
 671
 672         if (!(sb->s_flags & MS_RDONLY)) {
 673                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 674                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 675                 ext4_commit_super(sb, 1);
 676         }
 677         if (sbi->s_proc) {
 678                 remove_proc_entry(sb->s_id, ext4_proc_root);
 679         }
 680         kobject_del(&sbi->s_kobj);
 681
 682         for (i = 0; i < sbi->s_gdb_count; i++)
 683                 brelse(sbi->s_group_desc[i]);
 684         kfree(sbi->s_group_desc);
 685         if (is_vmalloc_addr(sbi->s_flex_groups))
 686                 vfree(sbi->s_flex_groups);
 687         else
 688                 kfree(sbi->s_flex_groups);
 689         percpu_counter_destroy(&sbi->s_freeblocks_counter);
 690         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 691         percpu_counter_destroy(&sbi->s_dirs_counter);
 692         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
 693         brelse(sbi->s_sbh);
 694 #ifdef CONFIG_QUOTA
 695         for (i = 0; i < MAXQUOTAS; i++)
 696                 kfree(sbi->s_qf_names[i]);
 697 #endif
 698
 699         /* Debugging code just in case the in-memory inode orphan list
 700          * isn't empty.  The on-disk one can be non-empty if we've
 701          * detected an error and taken the fs readonly, but the
 702          * in-memory list had better be clean by this point. */
 703         if (!list_empty(&sbi->s_orphan))
 704                 dump_orphan_list(sb, sbi);
 705         J_ASSERT(list_empty(&sbi->s_orphan));
 706
 707         invalidate_bdev(sb->s_bdev);
 708         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 709                 /*
 710                  * Invalidate the journal device's buffers.  We don't want them
 711                  * floating about in memory - the physical journal device may
 712                  * hotswapped, and it breaks the `ro-after' testing code.
 713                  */
 714                 sync_blockdev(sbi->journal_bdev);
 715                 invalidate_bdev(sbi->journal_bdev);
 716                 ext4_blkdev_remove(sbi);
 717         }
 718         sb->s_fs_info = NULL;
 719         /*
 720          * Now that we are completely done shutting down the
 721          * superblock, we need to actually destroy the kobject.
 722          */
 723         unlock_kernel();
 724         unlock_super(sb);
 725         kobject_put(&sbi->s_kobj);
 726         wait_for_completion(&sbi->s_kobj_unregister);
 727         kfree(sbi->s_blockgroup_lock);
 728         kfree(sbi);
 729 }
 730
 731 static struct kmem_cache *ext4_inode_cachep;
 732
 733 /*
 734  * Called inside transaction, so use GFP_NOFS
 735  */
 736 static struct inode *ext4_alloc_inode(struct super_block *sb)
 737 {
 738         struct ext4_inode_info *ei;
 739
 740         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 741         if (!ei)
 742                 return NULL;
 743
 744         ei->vfs_inode.i_version = 1;
 745         ei->vfs_inode.i_data.writeback_index = 0;
 746         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 747         INIT_LIST_HEAD(&ei->i_prealloc_list);
 748         spin_lock_init(&ei->i_prealloc_lock);
 749         /*
 750          * Note:  We can be called before EXT4_SB(sb)->s_journal is set,
 751          * therefore it can be null here.  Don't check it, just initialize
 752          * jinode.
 753          */
 754         jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
 755         ei->i_reserved_data_blocks = 0;
 756         ei->i_reserved_meta_blocks = 0;
 757         ei->i_allocated_meta_blocks = 0;
 758         ei->i_da_metadata_calc_len = 0;
 759         ei->i_delalloc_reserved_flag = 0;
 760         spin_lock_init(&(ei->i_block_reservation_lock));
 761 #ifdef CONFIG_QUOTA
 762         ei->i_reserved_quota = 0;
 763 #endif
 764         INIT_LIST_HEAD(&ei->i_completed_io_list);
 765         spin_lock_init(&ei->i_completed_io_lock);
 766         ei->cur_aio_dio = NULL;
 767         ei->i_sync_tid = 0;
 768         ei->i_datasync_tid = 0;
 769
 770         return &ei->vfs_inode;
 771 }
 772
 773 static void ext4_destroy_inode(struct inode *inode)
 774 {
 775         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 776                 ext4_msg(inode->i_sb, KERN_ERR,
 777                          "Inode %lu (%p): orphan list check failed!",
 778                          inode->i_ino, EXT4_I(inode));
 779                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 780                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 781                                 true);
 782                 dump_stack();
 783         }
 784         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 785 }
 786
 787 static void init_once(void *foo)
 788 {
 789         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 790
 791         INIT_LIST_HEAD(&ei->i_orphan);
 792 #ifdef CONFIG_EXT4_FS_XATTR
 793         init_rwsem(&ei->xattr_sem);
 794 #endif
 795         init_rwsem(&ei->i_data_sem);
 796         inode_init_once(&ei->vfs_inode);
 797 }
 798
 799 static int init_inodecache(void)
 800 {
 801         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 802                                              sizeof(struct ext4_inode_info),
 803                                              0, (SLAB_RECLAIM_ACCOUNT|
 804                                                 SLAB_MEM_SPREAD),
 805                                              init_once);
 806         if (ext4_inode_cachep == NULL)
 807                 return -ENOMEM;
 808         return 0;
 809 }
 810
 811 static void destroy_inodecache(void)
 812 {
 813         kmem_cache_destroy(ext4_inode_cachep);
 814 }
 815
 816 static void ext4_clear_inode(struct inode *inode)
 817 {
 818         dquot_drop(inode);
 819         ext4_discard_preallocations(inode);
 820         if (EXT4_JOURNAL(inode))
 821                 jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
 822                                        &EXT4_I(inode)->jinode);
 823 }
 824
 825 static inline void ext4_show_quota_options(struct seq_file *seq,
 826                                            struct super_block *sb)
 827 {
 828 #if defined(CONFIG_QUOTA)
 829         struct ext4_sb_info *sbi = EXT4_SB(sb);
 830
 831         if (sbi->s_jquota_fmt) {
 832                 char *fmtname = "";
 833
 834                 switch (sbi->s_jquota_fmt) {
 835                 case QFMT_VFS_OLD:
 836                         fmtname = "vfsold";
 837                         break;
 838                 case QFMT_VFS_V0:
 839                         fmtname = "vfsv0";
 840                         break;
 841                 case QFMT_VFS_V1:
 842                         fmtname = "vfsv1";
 843                         break;
 844                 }
 845                 seq_printf(seq, ",jqfmt=%s", fmtname);
 846         }
 847
 848         if (sbi->s_qf_names[USRQUOTA])
 849                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
 850
 851         if (sbi->s_qf_names[GRPQUOTA])
 852                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
 853
 854         if (test_opt(sb, USRQUOTA))
 855                 seq_puts(seq, ",usrquota");
 856
 857         if (test_opt(sb, GRPQUOTA))
 858                 seq_puts(seq, ",grpquota");
 859 #endif
 860 }
 861
 862 /*
 863  * Show an option if
 864  *  - it's set to a non-default value OR
 865  *  - if the per-sb default is different from the global default
 866  */
 867 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 868 {
 869         int def_errors;
 870         unsigned long def_mount_opts;
 871         struct super_block *sb = vfs->mnt_sb;
 872         struct ext4_sb_info *sbi = EXT4_SB(sb);
 873         struct ext4_super_block *es = sbi->s_es;
 874
 875         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 876         def_errors     = le16_to_cpu(es->s_errors);
 877
 878         if (sbi->s_sb_block != 1)
 879                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
 880         if (test_opt(sb, MINIX_DF))
 881                 seq_puts(seq, ",minixdf");
 882         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
 883                 seq_puts(seq, ",grpid");
 884         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
 885                 seq_puts(seq, ",nogrpid");
 886         if (sbi->s_resuid != EXT4_DEF_RESUID ||
 887             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
 888                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
 889         }
 890         if (sbi->s_resgid != EXT4_DEF_RESGID ||
 891             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
 892                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
 893         }
 894         if (test_opt(sb, ERRORS_RO)) {
 895                 if (def_errors == EXT4_ERRORS_PANIC ||
 896                     def_errors == EXT4_ERRORS_CONTINUE) {
 897                         seq_puts(seq, ",errors=remount-ro");
 898                 }
 899         }
 900         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
 901                 seq_puts(seq, ",errors=continue");
 902         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
 903                 seq_puts(seq, ",errors=panic");
 904         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
 905                 seq_puts(seq, ",nouid32");
 906         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
 907                 seq_puts(seq, ",debug");
 908         if (test_opt(sb, OLDALLOC))
 909                 seq_puts(seq, ",oldalloc");
 910 #ifdef CONFIG_EXT4_FS_XATTR
 911         if (test_opt(sb, XATTR_USER) &&
 912                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
 913                 seq_puts(seq, ",user_xattr");
 914         if (!test_opt(sb, XATTR_USER) &&
 915             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
 916                 seq_puts(seq, ",nouser_xattr");
 917         }
 918 #endif
 919 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 920         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
 921                 seq_puts(seq, ",acl");
 922         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
 923                 seq_puts(seq, ",noacl");
 924 #endif
 925         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
 926                 seq_printf(seq, ",commit=%u",
 927                            (unsigned) (sbi->s_commit_interval / HZ));
 928         }
 929         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
 930                 seq_printf(seq, ",min_batch_time=%u",
 931                            (unsigned) sbi->s_min_batch_time);
 932         }
 933         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
 934                 seq_printf(seq, ",max_batch_time=%u",
 935                            (unsigned) sbi->s_min_batch_time);
 936         }
 937
 938         /*
 939          * We're changing the default of barrier mount option, so
 940          * let's always display its mount state so it's clear what its
 941          * status is.
 942          */
 943         seq_puts(seq, ",barrier=");
 944         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
 945         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
 946                 seq_puts(seq, ",journal_async_commit");
 947         else if (test_opt(sb, JOURNAL_CHECKSUM))
 948                 seq_puts(seq, ",journal_checksum");
 949         if (test_opt(sb, I_VERSION))
 950                 seq_puts(seq, ",i_version");
 951         if (!test_opt(sb, DELALLOC))
 952                 seq_puts(seq, ",nodelalloc");
 953
 954
 955         if (sbi->s_stripe)
 956                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
 957         /*
 958          * journal mode get enabled in different ways
 959          * So just print the value even if we didn't specify it
 960          */
 961         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
 962                 seq_puts(seq, ",data=journal");
 963         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
 964                 seq_puts(seq, ",data=ordered");
 965         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
 966                 seq_puts(seq, ",data=writeback");
 967
 968         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
 969                 seq_printf(seq, ",inode_readahead_blks=%u",
 970                            sbi->s_inode_readahead_blks);
 971
 972         if (test_opt(sb, DATA_ERR_ABORT))
 973                 seq_puts(seq, ",data_err=abort");
 974
 975         if (test_opt(sb, NO_AUTO_DA_ALLOC))
 976                 seq_puts(seq, ",noauto_da_alloc");
 977
 978         if (test_opt(sb, DISCARD))
 979                 seq_puts(seq, ",discard");
 980
 981         if (test_opt(sb, NOLOAD))
 982                 seq_puts(seq, ",norecovery");
 983
 984         if (test_opt(sb, DIOREAD_NOLOCK))
 985                 seq_puts(seq, ",dioread_nolock");
 986
 987         ext4_show_quota_options(seq, sb);
 988
 989         return 0;
 990 }
 991
 992 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
 993                                         u64 ino, u32 generation)
 994 {
 995         struct inode *inode;
 996
 997         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 998                 return ERR_PTR(-ESTALE);
 999         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1000                 return ERR_PTR(-ESTALE);
1001
1002         /* iget isn't really right if the inode is currently unallocated!!
1003          *
1004          * ext4_read_inode will return a bad_inode if the inode had been
1005          * deleted, so we should be safe.
1006          *
1007          * Currently we don't know the generation for parent directory, so
1008          * a generation of 0 means "accept any"
1009          */
1010         inode = ext4_iget(sb, ino);
1011         if (IS_ERR(inode))
1012                 return ERR_CAST(inode);
1013         if (generation && inode->i_generation != generation) {
1014                 iput(inode);
1015                 return ERR_PTR(-ESTALE);
1016         }
1017
1018         return inode;
1019 }
1020
1021 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1022                                         int fh_len, int fh_type)
1023 {
1024         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1025                                     ext4_nfs_get_inode);
1026 }
1027
1028 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1029                                         int fh_len, int fh_type)
1030 {
1031         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1032                                     ext4_nfs_get_inode);
1033 }
1034
1035 /*
1036  * Try to release metadata pages (indirect blocks, directories) which are
1037  * mapped via the block device.  Since these pages could have journal heads
1038  * which would prevent try_to_free_buffers() from freeing them, we must use
1039  * jbd2 layer's try_to_free_buffers() function to release them.
1040  */
1041 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1042                                  gfp_t wait)
1043 {
1044         journal_t *journal = EXT4_SB(sb)->s_journal;
1045
1046         WARN_ON(PageChecked(page));
1047         if (!page_has_buffers(page))
1048                 return 0;
1049         if (journal)
1050                 return jbd2_journal_try_to_free_buffers(journal, page,
1051                                                         wait & ~__GFP_WAIT);
1052         return try_to_free_buffers(page);
1053 }
1054
1055 #ifdef CONFIG_QUOTA
1056 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1057 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1058
1059 static int ext4_write_dquot(struct dquot *dquot);
1060 static int ext4_acquire_dquot(struct dquot *dquot);
1061 static int ext4_release_dquot(struct dquot *dquot);
1062 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1063 static int ext4_write_info(struct super_block *sb, int type);
1064 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1065                                 char *path);
1066 static int ext4_quota_on_mount(struct super_block *sb, int type);
1067 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1068                                size_t len, loff_t off);
1069 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1070                                 const char *data, size_t len, loff_t off);
1071
1072 static const struct dquot_operations ext4_quota_operations = {
1073 #ifdef CONFIG_QUOTA
1074         .get_reserved_space = ext4_get_reserved_space,
1075 #endif
1076         .write_dquot    = ext4_write_dquot,
1077         .acquire_dquot  = ext4_acquire_dquot,
1078         .release_dquot  = ext4_release_dquot,
1079         .mark_dirty     = ext4_mark_dquot_dirty,
1080         .write_info     = ext4_write_info,
1081         .alloc_dquot    = dquot_alloc,
1082         .destroy_dquot  = dquot_destroy,
1083 };
1084
1085 static const struct quotactl_ops ext4_qctl_operations = {
1086         .quota_on       = ext4_quota_on,
1087         .quota_off      = dquot_quota_off,
1088         .quota_sync     = dquot_quota_sync,
1089         .get_info       = dquot_get_dqinfo,
1090         .set_info       = dquot_set_dqinfo,
1091         .get_dqblk      = dquot_get_dqblk,
1092         .set_dqblk      = dquot_set_dqblk
1093 };
1094 #endif
1095
1096 static const struct super_operations ext4_sops = {
1097         .alloc_inode    = ext4_alloc_inode,
1098         .destroy_inode  = ext4_destroy_inode,
1099         .write_inode    = ext4_write_inode,
1100         .dirty_inode    = ext4_dirty_inode,
1101         .delete_inode   = ext4_delete_inode,
1102         .put_super      = ext4_put_super,
1103         .sync_fs        = ext4_sync_fs,
1104         .freeze_fs      = ext4_freeze,
1105         .unfreeze_fs    = ext4_unfreeze,
1106         .statfs         = ext4_statfs,
1107         .remount_fs     = ext4_remount,
1108         .clear_inode    = ext4_clear_inode,
1109         .show_options   = ext4_show_options,
1110 #ifdef CONFIG_QUOTA
1111         .quota_read     = ext4_quota_read,
1112         .quota_write    = ext4_quota_write,
1113 #endif
1114         .bdev_try_to_free_page = bdev_try_to_free_page,
1115 };
1116
1117 static const struct super_operations ext4_nojournal_sops = {
1118         .alloc_inode    = ext4_alloc_inode,
1119         .destroy_inode  = ext4_destroy_inode,
1120         .write_inode    = ext4_write_inode,
1121         .dirty_inode    = ext4_dirty_inode,
1122         .delete_inode   = ext4_delete_inode,
1123         .write_super    = ext4_write_super,
1124         .put_super      = ext4_put_super,
1125         .statfs         = ext4_statfs,
1126         .remount_fs     = ext4_remount,
1127         .clear_inode    = ext4_clear_inode,
1128         .show_options   = ext4_show_options,
1129 #ifdef CONFIG_QUOTA
1130         .quota_read     = ext4_quota_read,
1131         .quota_write    = ext4_quota_write,
1132 #endif
1133         .bdev_try_to_free_page = bdev_try_to_free_page,
1134 };
1135
1136 static const struct export_operations ext4_export_ops = {
1137         .fh_to_dentry = ext4_fh_to_dentry,
1138         .fh_to_parent = ext4_fh_to_parent,
1139         .get_parent = ext4_get_parent,
1140 };
1141
1142 enum {
1143         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1144         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1145         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1146         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1147         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1148         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1149         Opt_journal_update, Opt_journal_dev,
1150         Opt_journal_checksum, Opt_journal_async_commit,
1151         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1152         Opt_data_err_abort, Opt_data_err_ignore,
1153         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1154         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1155         Opt_noquota, Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err,
1156         Opt_resize, Opt_usrquota, Opt_grpquota, Opt_i_version,
1157         Opt_stripe, Opt_delalloc, Opt_nodelalloc,
1158         Opt_block_validity, Opt_noblock_validity,
1159         Opt_inode_readahead_blks, Opt_journal_ioprio,
1160         Opt_dioread_nolock, Opt_dioread_lock,
1161         Opt_discard, Opt_nodiscard,
1162 };
1163
1164 static const match_table_t tokens = {
1165         {Opt_bsd_df, "bsddf"},
1166         {Opt_minix_df, "minixdf"},
1167         {Opt_grpid, "grpid"},
1168         {Opt_grpid, "bsdgroups"},
1169         {Opt_nogrpid, "nogrpid"},
1170         {Opt_nogrpid, "sysvgroups"},
1171         {Opt_resgid, "resgid=%u"},
1172         {Opt_resuid, "resuid=%u"},
1173         {Opt_sb, "sb=%u"},
1174         {Opt_err_cont, "errors=continue"},
1175         {Opt_err_panic, "errors=panic"},
1176         {Opt_err_ro, "errors=remount-ro"},
1177         {Opt_nouid32, "nouid32"},
1178         {Opt_debug, "debug"},
1179         {Opt_oldalloc, "oldalloc"},
1180         {Opt_orlov, "orlov"},
1181         {Opt_user_xattr, "user_xattr"},
1182         {Opt_nouser_xattr, "nouser_xattr"},
1183         {Opt_acl, "acl"},
1184         {Opt_noacl, "noacl"},
1185         {Opt_noload, "noload"},
1186         {Opt_noload, "norecovery"},
1187         {Opt_nobh, "nobh"},
1188         {Opt_bh, "bh"},
1189         {Opt_commit, "commit=%u"},
1190         {Opt_min_batch_time, "min_batch_time=%u"},
1191         {Opt_max_batch_time, "max_batch_time=%u"},
1192         {Opt_journal_update, "journal=update"},
1193         {Opt_journal_dev, "journal_dev=%u"},
1194         {Opt_journal_checksum, "journal_checksum"},
1195         {Opt_journal_async_commit, "journal_async_commit"},
1196         {Opt_abort, "abort"},
1197         {Opt_data_journal, "data=journal"},
1198         {Opt_data_ordered, "data=ordered"},
1199         {Opt_data_writeback, "data=writeback"},
1200         {Opt_data_err_abort, "data_err=abort"},
1201         {Opt_data_err_ignore, "data_err=ignore"},
1202         {Opt_offusrjquota, "usrjquota="},
1203         {Opt_usrjquota, "usrjquota=%s"},
1204         {Opt_offgrpjquota, "grpjquota="},
1205         {Opt_grpjquota, "grpjquota=%s"},
1206         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1207         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1208         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1209         {Opt_grpquota, "grpquota"},
1210         {Opt_noquota, "noquota"},
1211         {Opt_quota, "quota"},
1212         {Opt_usrquota, "usrquota"},
1213         {Opt_barrier, "barrier=%u"},
1214         {Opt_barrier, "barrier"},
1215         {Opt_nobarrier, "nobarrier"},
1216         {Opt_i_version, "i_version"},
1217         {Opt_stripe, "stripe=%u"},
1218         {Opt_resize, "resize"},
1219         {Opt_delalloc, "delalloc"},
1220         {Opt_nodelalloc, "nodelalloc"},
1221         {Opt_block_validity, "block_validity"},
1222         {Opt_noblock_validity, "noblock_validity"},
1223         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1224         {Opt_journal_ioprio, "journal_ioprio=%u"},
1225         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1226         {Opt_auto_da_alloc, "auto_da_alloc"},
1227         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1228         {Opt_dioread_nolock, "dioread_nolock"},
1229         {Opt_dioread_lock, "dioread_lock"},
1230         {Opt_discard, "discard"},
1231         {Opt_nodiscard, "nodiscard"},
1232         {Opt_err, NULL},
1233 };
1234
1235 static ext4_fsblk_t get_sb_block(void **data)
1236 {
1237         ext4_fsblk_t    sb_block;
1238         char            *options = (char *) *data;
1239
1240         if (!options || strncmp(options, "sb=", 3) != 0)
1241                 return 1;       /* Default location */
1242
1243         options += 3;
1244         /* TODO: use simple_strtoll with >32bit ext4 */
1245         sb_block = simple_strtoul(options, &options, 0);
1246         if (*options && *options != ',') {
1247                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1248                        (char *) *data);
1249                 return 1;
1250         }
1251         if (*options == ',')
1252                 options++;
1253         *data = (void *) options;
1254
1255         return sb_block;
1256 }
1257
1258 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1259 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1260         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1261
1262 #ifdef CONFIG_QUOTA
1263 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1264 {
1265         struct ext4_sb_info *sbi = EXT4_SB(sb);
1266         char *qname;
1267
1268         if (sb_any_quota_loaded(sb) &&
1269                 !sbi->s_qf_names[qtype]) {
1270                 ext4_msg(sb, KERN_ERR,
1271                         "Cannot change journaled "
1272                         "quota options when quota turned on");
1273                 return 0;
1274         }
1275         qname = match_strdup(args);
1276         if (!qname) {
1277                 ext4_msg(sb, KERN_ERR,
1278                         "Not enough memory for storing quotafile name");
1279                 return 0;
1280         }
1281         if (sbi->s_qf_names[qtype] &&
1282                 strcmp(sbi->s_qf_names[qtype], qname)) {
1283                 ext4_msg(sb, KERN_ERR,
1284                         "%s quota file already specified", QTYPE2NAME(qtype));
1285                 kfree(qname);
1286                 return 0;
1287         }
1288         sbi->s_qf_names[qtype] = qname;
1289         if (strchr(sbi->s_qf_names[qtype], '/')) {
1290                 ext4_msg(sb, KERN_ERR,
1291                         "quotafile must be on filesystem root");
1292                 kfree(sbi->s_qf_names[qtype]);
1293                 sbi->s_qf_names[qtype] = NULL;
1294                 return 0;
1295         }
1296         set_opt(sbi->s_mount_opt, QUOTA);
1297         return 1;
1298 }
1299
1300 static int clear_qf_name(struct super_block *sb, int qtype)
1301 {
1302
1303         struct ext4_sb_info *sbi = EXT4_SB(sb);
1304
1305         if (sb_any_quota_loaded(sb) &&
1306                 sbi->s_qf_names[qtype]) {
1307                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1308                         " when quota turned on");
1309                 return 0;
1310         }
1311         /*
1312          * The space will be released later when all options are confirmed
1313          * to be correct
1314          */
1315         sbi->s_qf_names[qtype] = NULL;
1316         return 1;
1317 }
1318 #endif
1319
1320 static int parse_options(char *options, struct super_block *sb,
1321                          unsigned long *journal_devnum,
1322                          unsigned int *journal_ioprio,
1323                          ext4_fsblk_t *n_blocks_count, int is_remount)
1324 {
1325         struct ext4_sb_info *sbi = EXT4_SB(sb);
1326         char *p;
1327         substring_t args[MAX_OPT_ARGS];
1328         int data_opt = 0;
1329         int option;
1330 #ifdef CONFIG_QUOTA
1331         int qfmt;
1332 #endif
1333
1334         if (!options)
1335                 return 1;
1336
1337         while ((p = strsep(&options, ",")) != NULL) {
1338                 int token;
1339                 if (!*p)
1340                         continue;
1341
1342                 /*
1343                  * Initialize args struct so we know whether arg was
1344                  * found; some options take optional arguments.
1345                  */
1346                 args[0].to = args[0].from = 0;
1347                 token = match_token(p, tokens, args);
1348                 switch (token) {
1349                 case Opt_bsd_df:
1350                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1351                         clear_opt(sbi->s_mount_opt, MINIX_DF);
1352                         break;
1353                 case Opt_minix_df:
1354                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1355                         set_opt(sbi->s_mount_opt, MINIX_DF);
1356
1357                         break;
1358                 case Opt_grpid:
1359                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1360                         set_opt(sbi->s_mount_opt, GRPID);
1361
1362                         break;
1363                 case Opt_nogrpid:
1364                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1365                         clear_opt(sbi->s_mount_opt, GRPID);
1366
1367                         break;
1368                 case Opt_resuid:
1369                         if (match_int(&args[0], &option))
1370                                 return 0;
1371                         sbi->s_resuid = option;
1372                         break;
1373                 case Opt_resgid:
1374                         if (match_int(&args[0], &option))
1375                                 return 0;
1376                         sbi->s_resgid = option;
1377                         break;
1378                 case Opt_sb:
1379                         /* handled by get_sb_block() instead of here */
1380                         /* *sb_block = match_int(&args[0]); */
1381                         break;
1382                 case Opt_err_panic:
1383                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1384                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1385                         set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1386                         break;
1387                 case Opt_err_ro:
1388                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1389                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1390                         set_opt(sbi->s_mount_opt, ERRORS_RO);
1391                         break;
1392                 case Opt_err_cont:
1393                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1394                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1395                         set_opt(sbi->s_mount_opt, ERRORS_CONT);
1396                         break;
1397                 case Opt_nouid32:
1398                         set_opt(sbi->s_mount_opt, NO_UID32);
1399                         break;
1400                 case Opt_debug:
1401                         set_opt(sbi->s_mount_opt, DEBUG);
1402                         break;
1403                 case Opt_oldalloc:
1404                         set_opt(sbi->s_mount_opt, OLDALLOC);
1405                         break;
1406                 case Opt_orlov:
1407                         clear_opt(sbi->s_mount_opt, OLDALLOC);
1408                         break;
1409 #ifdef CONFIG_EXT4_FS_XATTR
1410                 case Opt_user_xattr:
1411                         set_opt(sbi->s_mount_opt, XATTR_USER);
1412                         break;
1413                 case Opt_nouser_xattr:
1414                         clear_opt(sbi->s_mount_opt, XATTR_USER);
1415                         break;
1416 #else
1417                 case Opt_user_xattr:
1418                 case Opt_nouser_xattr:
1419                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1420                         break;
1421 #endif
1422 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1423                 case Opt_acl:
1424                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1425                         break;
1426                 case Opt_noacl:
1427                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1428                         break;
1429 #else
1430                 case Opt_acl:
1431                 case Opt_noacl:
1432                         ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1433                         break;
1434 #endif
1435                 case Opt_journal_update:
1436                         /* @@@ FIXME */
1437                         /* Eventually we will want to be able to create
1438                            a journal file here.  For now, only allow the
1439                            user to specify an existing inode to be the
1440                            journal file. */
1441                         if (is_remount) {
1442                                 ext4_msg(sb, KERN_ERR,
1443                                          "Cannot specify journal on remount");
1444                                 return 0;
1445                         }
1446                         set_opt(sbi->s_mount_opt, UPDATE_JOURNAL);
1447                         break;
1448                 case Opt_journal_dev:
1449                         if (is_remount) {
1450                                 ext4_msg(sb, KERN_ERR,
1451                                         "Cannot specify journal on remount");
1452                                 return 0;
1453                         }
1454                         if (match_int(&args[0], &option))
1455                                 return 0;
1456                         *journal_devnum = option;
1457                         break;
1458                 case Opt_journal_checksum:
1459                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1460                         break;
1461                 case Opt_journal_async_commit:
1462                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1463                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1464                         break;
1465                 case Opt_noload:
1466                         set_opt(sbi->s_mount_opt, NOLOAD);
1467                         break;
1468                 case Opt_commit:
1469                         if (match_int(&args[0], &option))
1470                                 return 0;
1471                         if (option < 0)
1472                                 return 0;
1473                         if (option == 0)
1474                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1475                         sbi->s_commit_interval = HZ * option;
1476                         break;
1477                 case Opt_max_batch_time:
1478                         if (match_int(&args[0], &option))
1479                                 return 0;
1480                         if (option < 0)
1481                                 return 0;
1482                         if (option == 0)
1483                                 option = EXT4_DEF_MAX_BATCH_TIME;
1484                         sbi->s_max_batch_time = option;
1485                         break;
1486                 case Opt_min_batch_time:
1487                         if (match_int(&args[0], &option))
1488                                 return 0;
1489                         if (option < 0)
1490                                 return 0;
1491                         sbi->s_min_batch_time = option;
1492                         break;
1493                 case Opt_data_journal:
1494                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1495                         goto datacheck;
1496                 case Opt_data_ordered:
1497                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1498                         goto datacheck;
1499                 case Opt_data_writeback:
1500                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1501                 datacheck:
1502                         if (is_remount) {
1503                                 if (test_opt(sb, DATA_FLAGS) != data_opt) {
1504                                         ext4_msg(sb, KERN_ERR,
1505                                                 "Cannot change data mode on remount");
1506                                         return 0;
1507                                 }
1508                         } else {
1509                                 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
1510                                 sbi->s_mount_opt |= data_opt;
1511                         }
1512                         break;
1513                 case Opt_data_err_abort:
1514                         set_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1515                         break;
1516                 case Opt_data_err_ignore:
1517                         clear_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1518                         break;
1519 #ifdef CONFIG_QUOTA
1520                 case Opt_usrjquota:
1521                         if (!set_qf_name(sb, USRQUOTA, &args[0]))
1522                                 return 0;
1523                         break;
1524                 case Opt_grpjquota:
1525                         if (!set_qf_name(sb, GRPQUOTA, &args[0]))
1526                                 return 0;
1527                         break;
1528                 case Opt_offusrjquota:
1529                         if (!clear_qf_name(sb, USRQUOTA))
1530                                 return 0;
1531                         break;
1532                 case Opt_offgrpjquota:
1533                         if (!clear_qf_name(sb, GRPQUOTA))
1534                                 return 0;
1535                         break;
1536
1537                 case Opt_jqfmt_vfsold:
1538                         qfmt = QFMT_VFS_OLD;
1539                         goto set_qf_format;
1540                 case Opt_jqfmt_vfsv0:
1541                         qfmt = QFMT_VFS_V0;
1542                         goto set_qf_format;
1543                 case Opt_jqfmt_vfsv1:
1544                         qfmt = QFMT_VFS_V1;
1545 set_qf_format:
1546                         if (sb_any_quota_loaded(sb) &&
1547                             sbi->s_jquota_fmt != qfmt) {
1548                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1549                                         "journaled quota options when "
1550                                         "quota turned on");
1551                                 return 0;
1552                         }
1553                         sbi->s_jquota_fmt = qfmt;
1554                         break;
1555                 case Opt_quota:
1556                 case Opt_usrquota:
1557                         set_opt(sbi->s_mount_opt, QUOTA);
1558                         set_opt(sbi->s_mount_opt, USRQUOTA);
1559                         break;
1560                 case Opt_grpquota:
1561                         set_opt(sbi->s_mount_opt, QUOTA);
1562                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1563                         break;
1564                 case Opt_noquota:
1565                         if (sb_any_quota_loaded(sb)) {
1566                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1567                                         "options when quota turned on");
1568                                 return 0;
1569                         }
1570                         clear_opt(sbi->s_mount_opt, QUOTA);
1571                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1572                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1573                         break;
1574 #else
1575                 case Opt_quota:
1576                 case Opt_usrquota:
1577                 case Opt_grpquota:
1578                         ext4_msg(sb, KERN_ERR,
1579                                 "quota options not supported");
1580                         break;
1581                 case Opt_usrjquota:
1582                 case Opt_grpjquota:
1583                 case Opt_offusrjquota:
1584                 case Opt_offgrpjquota:
1585                 case Opt_jqfmt_vfsold:
1586                 case Opt_jqfmt_vfsv0:
1587                 case Opt_jqfmt_vfsv1:
1588                         ext4_msg(sb, KERN_ERR,
1589                                 "journaled quota options not supported");
1590                         break;
1591                 case Opt_noquota:
1592                         break;
1593 #endif
1594                 case Opt_abort:
1595                         sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1596                         break;
1597                 case Opt_nobarrier:
1598                         clear_opt(sbi->s_mount_opt, BARRIER);
1599                         break;
1600                 case Opt_barrier:
1601                         if (args[0].from) {
1602                                 if (match_int(&args[0], &option))
1603                                         return 0;
1604                         } else
1605                                 option = 1;     /* No argument, default to 1 */
1606                         if (option)
1607                                 set_opt(sbi->s_mount_opt, BARRIER);
1608                         else
1609                                 clear_opt(sbi->s_mount_opt, BARRIER);
1610                         break;
1611                 case Opt_ignore:
1612                         break;
1613                 case Opt_resize:
1614                         if (!is_remount) {
1615                                 ext4_msg(sb, KERN_ERR,
1616                                         "resize option only available "
1617                                         "for remount");
1618                                 return 0;
1619                         }
1620                         if (match_int(&args[0], &option) != 0)
1621                                 return 0;
1622                         *n_blocks_count = option;
1623                         break;
1624                 case Opt_nobh:
1625                         ext4_msg(sb, KERN_WARNING,
1626                                  "Ignoring deprecated nobh option");
1627                         break;
1628                 case Opt_bh:
1629                         ext4_msg(sb, KERN_WARNING,
1630                                  "Ignoring deprecated bh option");
1631                         break;
1632                 case Opt_i_version:
1633                         set_opt(sbi->s_mount_opt, I_VERSION);
1634                         sb->s_flags |= MS_I_VERSION;
1635                         break;
1636                 case Opt_nodelalloc:
1637                         clear_opt(sbi->s_mount_opt, DELALLOC);
1638                         break;
1639                 case Opt_stripe:
1640                         if (match_int(&args[0], &option))
1641                                 return 0;
1642                         if (option < 0)
1643                                 return 0;
1644                         sbi->s_stripe = option;
1645                         break;
1646                 case Opt_delalloc:
1647                         set_opt(sbi->s_mount_opt, DELALLOC);
1648                         break;
1649                 case Opt_block_validity:
1650                         set_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1651                         break;
1652                 case Opt_noblock_validity:
1653                         clear_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1654                         break;
1655                 case Opt_inode_readahead_blks:
1656                         if (match_int(&args[0], &option))
1657                                 return 0;
1658                         if (option < 0 || option > (1 << 30))
1659                                 return 0;
1660                         if (!is_power_of_2(option)) {
1661                                 ext4_msg(sb, KERN_ERR,
1662                                          "EXT4-fs: inode_readahead_blks"
1663                                          " must be a power of 2");
1664                                 return 0;
1665                         }
1666                         sbi->s_inode_readahead_blks = option;
1667                         break;
1668                 case Opt_journal_ioprio:
1669                         if (match_int(&args[0], &option))
1670                                 return 0;
1671                         if (option < 0 || option > 7)
1672                                 break;
1673                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1674                                                             option);
1675                         break;
1676                 case Opt_noauto_da_alloc:
1677                         set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1678                         break;
1679                 case Opt_auto_da_alloc:
1680                         if (args[0].from) {
1681                                 if (match_int(&args[0], &option))
1682                                         return 0;
1683                         } else
1684                                 option = 1;     /* No argument, default to 1 */
1685                         if (option)
1686                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1687                         else
1688                                 set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1689                         break;
1690                 case Opt_discard:
1691                         set_opt(sbi->s_mount_opt, DISCARD);
1692                         break;
1693                 case Opt_nodiscard:
1694                         clear_opt(sbi->s_mount_opt, DISCARD);
1695                         break;
1696                 case Opt_dioread_nolock:
1697                         set_opt(sbi->s_mount_opt, DIOREAD_NOLOCK);
1698                         break;
1699                 case Opt_dioread_lock:
1700                         clear_opt(sbi->s_mount_opt, DIOREAD_NOLOCK);
1701                         break;
1702                 default:
1703                         ext4_msg(sb, KERN_ERR,
1704                                "Unrecognized mount option \"%s\" "
1705                                "or missing value", p);
1706                         return 0;
1707                 }
1708         }
1709 #ifdef CONFIG_QUOTA
1710         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1711                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1712                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1713
1714                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1715                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1716
1717                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1718                         ext4_msg(sb, KERN_ERR, "old and new quota "
1719                                         "format mixing");
1720                         return 0;
1721                 }
1722
1723                 if (!sbi->s_jquota_fmt) {
1724                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1725                                         "not specified");
1726                         return 0;
1727                 }
1728         } else {
1729                 if (sbi->s_jquota_fmt) {
1730                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1731                                         "specified with no journaling "
1732                                         "enabled");
1733                         return 0;
1734                 }
1735         }
1736 #endif
1737         return 1;
1738 }
1739
1740 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1741                             int read_only)
1742 {
1743         struct ext4_sb_info *sbi = EXT4_SB(sb);
1744         int res = 0;
1745
1746         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1747                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1748                          "forcing read-only mode");
1749                 res = MS_RDONLY;
1750         }
1751         if (read_only)
1752                 return res;
1753         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1754                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1755                          "running e2fsck is recommended");
1756         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1757                 ext4_msg(sb, KERN_WARNING,
1758                          "warning: mounting fs with errors, "
1759                          "running e2fsck is recommended");
1760         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1761                  le16_to_cpu(es->s_mnt_count) >=
1762                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1763                 ext4_msg(sb, KERN_WARNING,
1764                          "warning: maximal mount count reached, "
1765                          "running e2fsck is recommended");
1766         else if (le32_to_cpu(es->s_checkinterval) &&
1767                 (le32_to_cpu(es->s_lastcheck) +
1768                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1769                 ext4_msg(sb, KERN_WARNING,
1770                          "warning: checktime reached, "
1771                          "running e2fsck is recommended");
1772         if (!sbi->s_journal)
1773                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1774         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1775                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1776         le16_add_cpu(&es->s_mnt_count, 1);
1777         es->s_mtime = cpu_to_le32(get_seconds());
1778         ext4_update_dynamic_rev(sb);
1779         if (sbi->s_journal)
1780                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1781
1782         ext4_commit_super(sb, 1);
1783         if (test_opt(sb, DEBUG))
1784                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1785                                 "bpg=%lu, ipg=%lu, mo=%04x]\n",
1786                         sb->s_blocksize,
1787                         sbi->s_groups_count,
1788                         EXT4_BLOCKS_PER_GROUP(sb),
1789                         EXT4_INODES_PER_GROUP(sb),
1790                         sbi->s_mount_opt);
1791
1792         return res;
1793 }
1794
1795 static int ext4_fill_flex_info(struct super_block *sb)
1796 {
1797         struct ext4_sb_info *sbi = EXT4_SB(sb);
1798         struct ext4_group_desc *gdp = NULL;
1799         ext4_group_t flex_group_count;
1800         ext4_group_t flex_group;
1801         int groups_per_flex = 0;
1802         size_t size;
1803         int i;
1804
1805         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1806         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1807
1808         if (groups_per_flex < 2) {
1809                 sbi->s_log_groups_per_flex = 0;
1810                 return 1;
1811         }
1812
1813         /* We allocate both existing and potentially added groups */
1814         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1815                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1816                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1817         size = flex_group_count * sizeof(struct flex_groups);
1818         sbi->s_flex_groups = kzalloc(size, GFP_KERNEL);
1819         if (sbi->s_flex_groups == NULL) {
1820                 sbi->s_flex_groups = vmalloc(size);
1821                 if (sbi->s_flex_groups)
1822                         memset(sbi->s_flex_groups, 0, size);
1823         }
1824         if (sbi->s_flex_groups == NULL) {
1825                 ext4_msg(sb, KERN_ERR, "not enough memory for "
1826                                 "%u flex groups", flex_group_count);
1827                 goto failed;
1828         }
1829
1830         for (i = 0; i < sbi->s_groups_count; i++) {
1831                 gdp = ext4_get_group_desc(sb, i, NULL);
1832
1833                 flex_group = ext4_flex_group(sbi, i);
1834                 atomic_add(ext4_free_inodes_count(sb, gdp),
1835                            &sbi->s_flex_groups[flex_group].free_inodes);
1836                 atomic_add(ext4_free_blks_count(sb, gdp),
1837                            &sbi->s_flex_groups[flex_group].free_blocks);
1838                 atomic_add(ext4_used_dirs_count(sb, gdp),
1839                            &sbi->s_flex_groups[flex_group].used_dirs);
1840         }
1841
1842         return 1;
1843 failed:
1844         return 0;
1845 }
1846
1847 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1848                             struct ext4_group_desc *gdp)
1849 {
1850         __u16 crc = 0;
1851
1852         if (sbi->s_es->s_feature_ro_compat &
1853             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1854                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1855                 __le32 le_group = cpu_to_le32(block_group);
1856
1857                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1858                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1859                 crc = crc16(crc, (__u8 *)gdp, offset);
1860                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1861                 /* for checksum of struct ext4_group_desc do the rest...*/
1862                 if ((sbi->s_es->s_feature_incompat &
1863                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1864                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1865                         crc = crc16(crc, (__u8 *)gdp + offset,
1866                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1867                                         offset);
1868         }
1869
1870         return cpu_to_le16(crc);
1871 }
1872
1873 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1874                                 struct ext4_group_desc *gdp)
1875 {
1876         if ((sbi->s_es->s_feature_ro_compat &
1877              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1878             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1879                 return 0;
1880
1881         return 1;
1882 }
1883
1884 /* Called at mount-time, super-block is locked */
1885 static int ext4_check_descriptors(struct super_block *sb)
1886 {
1887         struct ext4_sb_info *sbi = EXT4_SB(sb);
1888         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1889         ext4_fsblk_t last_block;
1890         ext4_fsblk_t block_bitmap;
1891         ext4_fsblk_t inode_bitmap;
1892         ext4_fsblk_t inode_table;
1893         int flexbg_flag = 0;
1894         ext4_group_t i;
1895
1896         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1897                 flexbg_flag = 1;
1898
1899         ext4_debug("Checking group descriptors");
1900
1901         for (i = 0; i < sbi->s_groups_count; i++) {
1902                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1903
1904                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1905                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1906                 else
1907                         last_block = first_block +
1908                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1909
1910                 block_bitmap = ext4_block_bitmap(sb, gdp);
1911                 if (block_bitmap < first_block || block_bitmap > last_block) {
1912                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1913                                "Block bitmap for group %u not in group "
1914                                "(block %llu)!", i, block_bitmap);
1915                         return 0;
1916                 }
1917                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1918                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1919                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1920                                "Inode bitmap for group %u not in group "
1921                                "(block %llu)!", i, inode_bitmap);
1922                         return 0;
1923                 }
1924                 inode_table = ext4_inode_table(sb, gdp);
1925                 if (inode_table < first_block ||
1926                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
1927                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1928                                "Inode table for group %u not in group "
1929                                "(block %llu)!", i, inode_table);
1930                         return 0;
1931                 }
1932                 ext4_lock_group(sb, i);
1933                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1934                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1935                                  "Checksum for group %u failed (%u!=%u)",
1936                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1937                                      gdp)), le16_to_cpu(gdp->bg_checksum));
1938                         if (!(sb->s_flags & MS_RDONLY)) {
1939                                 ext4_unlock_group(sb, i);
1940                                 return 0;
1941                         }
1942                 }
1943                 ext4_unlock_group(sb, i);
1944                 if (!flexbg_flag)
1945                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1946         }
1947
1948         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1949         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
1950         return 1;
1951 }
1952
1953 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1954  * the superblock) which were deleted from all directories, but held open by
1955  * a process at the time of a crash.  We walk the list and try to delete these
1956  * inodes at recovery time (only with a read-write filesystem).
1957  *
1958  * In order to keep the orphan inode chain consistent during traversal (in
1959  * case of crash during recovery), we link each inode into the superblock
1960  * orphan list_head and handle it the same way as an inode deletion during
1961  * normal operation (which journals the operations for us).
1962  *
1963  * We only do an iget() and an iput() on each inode, which is very safe if we
1964  * accidentally point at an in-use or already deleted inode.  The worst that
1965  * can happen in this case is that we get a "bit already cleared" message from
1966  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1967  * e2fsck was run on this filesystem, and it must have already done the orphan
1968  * inode cleanup for us, so we can safely abort without any further action.
1969  */
1970 static void ext4_orphan_cleanup(struct super_block *sb,
1971                                 struct ext4_super_block *es)
1972 {
1973         unsigned int s_flags = sb->s_flags;
1974         int nr_orphans = 0, nr_truncates = 0;
1975 #ifdef CONFIG_QUOTA
1976         int i;
1977 #endif
1978         if (!es->s_last_orphan) {
1979                 jbd_debug(4, "no orphan inodes to clean up\n");
1980                 return;
1981         }
1982
1983         if (bdev_read_only(sb->s_bdev)) {
1984                 ext4_msg(sb, KERN_ERR, "write access "
1985                         "unavailable, skipping orphan cleanup");
1986                 return;
1987         }
1988
1989         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1990                 if (es->s_last_orphan)
1991                         jbd_debug(1, "Errors on filesystem, "
1992                                   "clearing orphan list.\n");
1993                 es->s_last_orphan = 0;
1994                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1995                 return;
1996         }
1997
1998         if (s_flags & MS_RDONLY) {
1999                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2000                 sb->s_flags &= ~MS_RDONLY;
2001         }
2002 #ifdef CONFIG_QUOTA
2003         /* Needed for iput() to work correctly and not trash data */
2004         sb->s_flags |= MS_ACTIVE;
2005         /* Turn on quotas so that they are updated correctly */
2006         for (i = 0; i < MAXQUOTAS; i++) {
2007                 if (EXT4_SB(sb)->s_qf_names[i]) {
2008                         int ret = ext4_quota_on_mount(sb, i);
2009                         if (ret < 0)
2010                                 ext4_msg(sb, KERN_ERR,
2011                                         "Cannot turn on journaled "
2012                                         "quota: error %d", ret);
2013                 }
2014         }
2015 #endif
2016
2017         while (es->s_last_orphan) {
2018                 struct inode *inode;
2019
2020                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2021                 if (IS_ERR(inode)) {
2022                         es->s_last_orphan = 0;
2023                         break;
2024                 }
2025
2026                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2027                 dquot_initialize(inode);
2028                 if (inode->i_nlink) {
2029                         ext4_msg(sb, KERN_DEBUG,
2030                                 "%s: truncating inode %lu to %lld bytes",
2031                                 __func__, inode->i_ino, inode->i_size);
2032                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2033                                   inode->i_ino, inode->i_size);
2034                         ext4_truncate(inode);
2035                         nr_truncates++;
2036                 } else {
2037                         ext4_msg(sb, KERN_DEBUG,
2038                                 "%s: deleting unreferenced inode %lu",
2039                                 __func__, inode->i_ino);
2040                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2041                                   inode->i_ino);
2042                         nr_orphans++;
2043                 }
2044                 iput(inode);  /* The delete magic happens here! */
2045         }
2046
2047 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2048
2049         if (nr_orphans)
2050                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2051                        PLURAL(nr_orphans));
2052         if (nr_truncates)
2053                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2054                        PLURAL(nr_truncates));
2055 #ifdef CONFIG_QUOTA
2056         /* Turn quotas off */
2057         for (i = 0; i < MAXQUOTAS; i++) {
2058                 if (sb_dqopt(sb)->files[i])
2059                         dquot_quota_off(sb, i);
2060         }
2061 #endif
2062         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2063 }
2064
2065 /*
2066  * Maximal extent format file size.
2067  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2068  * extent format containers, within a sector_t, and within i_blocks
2069  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2070  * so that won't be a limiting factor.
2071  *
2072  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2073  */
2074 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2075 {
2076         loff_t res;
2077         loff_t upper_limit = MAX_LFS_FILESIZE;
2078
2079         /* small i_blocks in vfs inode? */
2080         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2081                 /*
2082                  * CONFIG_LBDAF is not enabled implies the inode
2083                  * i_block represent total blocks in 512 bytes
2084                  * 32 == size of vfs inode i_blocks * 8
2085                  */
2086                 upper_limit = (1LL << 32) - 1;
2087
2088                 /* total blocks in file system block size */
2089                 upper_limit >>= (blkbits - 9);
2090                 upper_limit <<= blkbits;
2091         }
2092
2093         /* 32-bit extent-start container, ee_block */
2094         res = 1LL << 32;
2095         res <<= blkbits;
2096         res -= 1;
2097
2098         /* Sanity check against vm- & vfs- imposed limits */
2099         if (res > upper_limit)
2100                 res = upper_limit;
2101
2102         return res;
2103 }
2104
2105 /*
2106  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2107  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2108  * We need to be 1 filesystem block less than the 2^48 sector limit.
2109  */
2110 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2111 {
2112         loff_t res = EXT4_NDIR_BLOCKS;
2113         int meta_blocks;
2114         loff_t upper_limit;
2115         /* This is calculated to be the largest file size for a dense, block
2116          * mapped file such that the file's total number of 512-byte sectors,
2117          * including data and all indirect blocks, does not exceed (2^48 - 1).
2118          *
2119          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2120          * number of 512-byte sectors of the file.
2121          */
2122
2123         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2124                 /*
2125                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2126                  * the inode i_block field represents total file blocks in
2127                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2128                  */
2129                 upper_limit = (1LL << 32) - 1;
2130
2131                 /* total blocks in file system block size */
2132                 upper_limit >>= (bits - 9);
2133
2134         } else {
2135                 /*
2136                  * We use 48 bit ext4_inode i_blocks
2137                  * With EXT4_HUGE_FILE_FL set the i_blocks
2138                  * represent total number of blocks in
2139                  * file system block size
2140                  */
2141                 upper_limit = (1LL << 48) - 1;
2142
2143         }
2144
2145         /* indirect blocks */
2146         meta_blocks = 1;
2147         /* double indirect blocks */
2148         meta_blocks += 1 + (1LL << (bits-2));
2149         /* tripple indirect blocks */
2150         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2151
2152         upper_limit -= meta_blocks;
2153         upper_limit <<= bits;
2154
2155         res += 1LL << (bits-2);
2156         res += 1LL << (2*(bits-2));
2157         res += 1LL << (3*(bits-2));
2158         res <<= bits;
2159         if (res > upper_limit)
2160                 res = upper_limit;
2161
2162         if (res > MAX_LFS_FILESIZE)
2163                 res = MAX_LFS_FILESIZE;
2164
2165         return res;
2166 }
2167
2168 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2169                                    ext4_fsblk_t logical_sb_block, int nr)
2170 {
2171         struct ext4_sb_info *sbi = EXT4_SB(sb);
2172         ext4_group_t bg, first_meta_bg;
2173         int has_super = 0;
2174
2175         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2176
2177         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2178             nr < first_meta_bg)
2179                 return logical_sb_block + nr + 1;
2180         bg = sbi->s_desc_per_block * nr;
2181         if (ext4_bg_has_super(sb, bg))
2182                 has_super = 1;
2183
2184         return (has_super + ext4_group_first_block_no(sb, bg));
2185 }
2186
2187 /**
2188  * ext4_get_stripe_size: Get the stripe size.
2189  * @sbi: In memory super block info
2190  *
2191  * If we have specified it via mount option, then
2192  * use the mount option value. If the value specified at mount time is
2193  * greater than the blocks per group use the super block value.
2194  * If the super block value is greater than blocks per group return 0.
2195  * Allocator needs it be less than blocks per group.
2196  *
2197  */
2198 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2199 {
2200         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2201         unsigned long stripe_width =
2202                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2203
2204         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2205                 return sbi->s_stripe;
2206
2207         if (stripe_width <= sbi->s_blocks_per_group)
2208                 return stripe_width;
2209
2210         if (stride <= sbi->s_blocks_per_group)
2211                 return stride;
2212
2213         return 0;
2214 }
2215
2216 /* sysfs supprt */
2217
2218 struct ext4_attr {
2219         struct attribute attr;
2220         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2221         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2222                          const char *, size_t);
2223         int offset;
2224 };
2225
2226 static int parse_strtoul(const char *buf,
2227                 unsigned long max, unsigned long *value)
2228 {
2229         char *endp;
2230
2231         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2232         endp = skip_spaces(endp);
2233         if (*endp || *value > max)
2234                 return -EINVAL;
2235
2236         return 0;
2237 }
2238
2239 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2240                                               struct ext4_sb_info *sbi,
2241                                               char *buf)
2242 {
2243         return snprintf(buf, PAGE_SIZE, "%llu\n",
2244                         (s64) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
2245 }
2246
2247 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2248                                          struct ext4_sb_info *sbi, char *buf)
2249 {
2250         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2251
2252         return snprintf(buf, PAGE_SIZE, "%lu\n",
2253                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2254                          sbi->s_sectors_written_start) >> 1);
2255 }
2256
2257 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2258                                           struct ext4_sb_info *sbi, char *buf)
2259 {
2260         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2261
2262         return snprintf(buf, PAGE_SIZE, "%llu\n",
2263                         (unsigned long long)(sbi->s_kbytes_written +
2264                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2265                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2266 }
2267
2268 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2269                                           struct ext4_sb_info *sbi,
2270                                           const char *buf, size_t count)
2271 {
2272         unsigned long t;
2273
2274         if (parse_strtoul(buf, 0x40000000, &t))
2275                 return -EINVAL;
2276
2277         if (!is_power_of_2(t))
2278                 return -EINVAL;
2279
2280         sbi->s_inode_readahead_blks = t;
2281         return count;
2282 }
2283
2284 static ssize_t sbi_ui_show(struct ext4_attr *a,
2285                            struct ext4_sb_info *sbi, char *buf)
2286 {
2287         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2288
2289         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2290 }
2291
2292 static ssize_t sbi_ui_store(struct ext4_attr *a,
2293                             struct ext4_sb_info *sbi,
2294                             const char *buf, size_t count)
2295 {
2296         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2297         unsigned long t;
2298
2299         if (parse_strtoul(buf, 0xffffffff, &t))
2300                 return -EINVAL;
2301         *ui = t;
2302         return count;
2303 }
2304
2305 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2306 static struct ext4_attr ext4_attr_##_name = {                   \
2307         .attr = {.name = __stringify(_name), .mode = _mode },   \
2308         .show   = _show,                                        \
2309         .store  = _store,                                       \
2310         .offset = offsetof(struct ext4_sb_info, _elname),       \
2311 }
2312 #define EXT4_ATTR(name, mode, show, store) \
2313 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2314
2315 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2316 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2317 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2318         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2319 #define ATTR_LIST(name) &ext4_attr_##name.attr
2320
2321 EXT4_RO_ATTR(delayed_allocation_blocks);
2322 EXT4_RO_ATTR(session_write_kbytes);
2323 EXT4_RO_ATTR(lifetime_write_kbytes);
2324 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2325                  inode_readahead_blks_store, s_inode_readahead_blks);
2326 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2327 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2328 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2329 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2330 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2331 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2332 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2333 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2334
2335 static struct attribute *ext4_attrs[] = {
2336         ATTR_LIST(delayed_allocation_blocks),
2337         ATTR_LIST(session_write_kbytes),
2338         ATTR_LIST(lifetime_write_kbytes),
2339         ATTR_LIST(inode_readahead_blks),
2340         ATTR_LIST(inode_goal),
2341         ATTR_LIST(mb_stats),
2342         ATTR_LIST(mb_max_to_scan),
2343         ATTR_LIST(mb_min_to_scan),
2344         ATTR_LIST(mb_order2_req),
2345         ATTR_LIST(mb_stream_req),
2346         ATTR_LIST(mb_group_prealloc),
2347         ATTR_LIST(max_writeback_mb_bump),
2348         NULL,
2349 };
2350
2351 static ssize_t ext4_attr_show(struct kobject *kobj,
2352                               struct attribute *attr, char *buf)
2353 {
2354         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2355                                                 s_kobj);
2356         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2357
2358         return a->show ? a->show(a, sbi, buf) : 0;
2359 }
2360
2361 static ssize_t ext4_attr_store(struct kobject *kobj,
2362                                struct attribute *attr,
2363                                const char *buf, size_t len)
2364 {
2365         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2366                                                 s_kobj);
2367         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2368
2369         return a->store ? a->store(a, sbi, buf, len) : 0;
2370 }
2371
2372 static void ext4_sb_release(struct kobject *kobj)
2373 {
2374         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2375                                                 s_kobj);
2376         complete(&sbi->s_kobj_unregister);
2377 }
2378
2379
2380 static const struct sysfs_ops ext4_attr_ops = {
2381         .show   = ext4_attr_show,
2382         .store  = ext4_attr_store,
2383 };
2384
2385 static struct kobj_type ext4_ktype = {
2386         .default_attrs  = ext4_attrs,
2387         .sysfs_ops      = &ext4_attr_ops,
2388         .release        = ext4_sb_release,
2389 };
2390
2391 /*
2392  * Check whether this filesystem can be mounted based on
2393  * the features present and the RDONLY/RDWR mount requested.
2394  * Returns 1 if this filesystem can be mounted as requested,
2395  * 0 if it cannot be.
2396  */
2397 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2398 {
2399         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2400                 ext4_msg(sb, KERN_ERR,
2401                         "Couldn't mount because of "
2402                         "unsupported optional features (%x)",
2403                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2404                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2405                 return 0;
2406         }
2407
2408         if (readonly)
2409                 return 1;
2410
2411         /* Check that feature set is OK for a read-write mount */
2412         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2413                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2414                          "unsupported optional features (%x)",
2415                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2416                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2417                 return 0;
2418         }
2419         /*
2420          * Large file size enabled file system can only be mounted
2421          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2422          */
2423         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2424                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2425                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2426                                  "cannot be mounted RDWR without "
2427                                  "CONFIG_LBDAF");
2428                         return 0;
2429                 }
2430         }
2431         return 1;
2432 }
2433
2434 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
2435                                 __releases(kernel_lock)
2436                                 __acquires(kernel_lock)
2437 {
2438         char *orig_data = kstrdup(data, GFP_KERNEL);
2439         struct buffer_head *bh;
2440         struct ext4_super_block *es = NULL;
2441         struct ext4_sb_info *sbi;
2442         ext4_fsblk_t block;
2443         ext4_fsblk_t sb_block = get_sb_block(&data);
2444         ext4_fsblk_t logical_sb_block;
2445         unsigned long offset = 0;
2446         unsigned long journal_devnum = 0;
2447         unsigned long def_mount_opts;
2448         struct inode *root;
2449         char *cp;
2450         const char *descr;
2451         int ret = -EINVAL;
2452         int blocksize;
2453         unsigned int db_count;
2454         unsigned int i;
2455         int needs_recovery, has_huge_files;
2456         __u64 blocks_count;
2457         int err;
2458         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
2459
2460         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2461         if (!sbi)
2462                 return -ENOMEM;
2463
2464         sbi->s_blockgroup_lock =
2465                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
2466         if (!sbi->s_blockgroup_lock) {
2467                 kfree(sbi);
2468                 return -ENOMEM;
2469         }
2470         sb->s_fs_info = sbi;
2471         sbi->s_mount_opt = 0;
2472         sbi->s_resuid = EXT4_DEF_RESUID;
2473         sbi->s_resgid = EXT4_DEF_RESGID;
2474         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
2475         sbi->s_sb_block = sb_block;
2476         sbi->s_sectors_written_start = part_stat_read(sb->s_bdev->bd_part,
2477                                                       sectors[1]);
2478
2479         unlock_kernel();
2480
2481         /* Cleanup superblock name */
2482         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
2483                 *cp = '!';
2484
2485         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
2486         if (!blocksize) {
2487                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
2488                 goto out_fail;
2489         }
2490
2491         /*
2492          * The ext4 superblock will not be buffer aligned for other than 1kB
2493          * block sizes.  We need to calculate the offset from buffer start.
2494          */
2495         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
2496                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2497                 offset = do_div(logical_sb_block, blocksize);
2498         } else {
2499                 logical_sb_block = sb_block;
2500         }
2501
2502         if (!(bh = sb_bread(sb, logical_sb_block))) {
2503                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
2504                 goto out_fail;
2505         }
2506         /*
2507          * Note: s_es must be initialized as soon as possible because
2508          *       some ext4 macro-instructions depend on its value
2509          */
2510         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2511         sbi->s_es = es;
2512         sb->s_magic = le16_to_cpu(es->s_magic);
2513         if (sb->s_magic != EXT4_SUPER_MAGIC)
2514                 goto cantfind_ext4;
2515         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
2516
2517         /* Set defaults before we parse the mount options */
2518         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
2519         if (def_mount_opts & EXT4_DEFM_DEBUG)
2520                 set_opt(sbi->s_mount_opt, DEBUG);
2521         if (def_mount_opts & EXT4_DEFM_BSDGROUPS) {
2522                 ext4_msg(sb, KERN_WARNING, deprecated_msg, "bsdgroups",
2523                         "2.6.38");
2524                 set_opt(sbi->s_mount_opt, GRPID);
2525         }
2526         if (def_mount_opts & EXT4_DEFM_UID16)
2527                 set_opt(sbi->s_mount_opt, NO_UID32);
2528 #ifdef CONFIG_EXT4_FS_XATTR
2529         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
2530                 set_opt(sbi->s_mount_opt, XATTR_USER);
2531 #endif
2532 #ifdef CONFIG_EXT4_FS_POSIX_ACL
2533         if (def_mount_opts & EXT4_DEFM_ACL)
2534                 set_opt(sbi->s_mount_opt, POSIX_ACL);
2535 #endif
2536         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
2537                 set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2538         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
2539                 set_opt(sbi->s_mount_opt, ORDERED_DATA);
2540         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
2541                 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
2542
2543         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
2544                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
2545         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
2546                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
2547         else
2548                 set_opt(sbi->s_mount_opt, ERRORS_RO);
2549
2550         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2551         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2552         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
2553         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
2554         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
2555
2556         set_opt(sbi->s_mount_opt, BARRIER);
2557
2558         /*
2559          * enable delayed allocation by default
2560          * Use -o nodelalloc to turn it off
2561          */
2562         if (!IS_EXT3_SB(sb))
2563                 set_opt(sbi->s_mount_opt, DELALLOC);
2564
2565         if (!parse_options((char *) data, sb, &journal_devnum,
2566                            &journal_ioprio, NULL, 0))
2567                 goto failed_mount;
2568
2569         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2570                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
2571
2572         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2573             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2574              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2575              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2576                 ext4_msg(sb, KERN_WARNING,
2577                        "feature flags set on rev 0 fs, "
2578                        "running e2fsck is recommended");
2579
2580         /*
2581          * Check feature flags regardless of the revision level, since we
2582          * previously didn't change the revision level when setting the flags,
2583          * so there is a chance incompat flags are set on a rev 0 filesystem.
2584          */
2585         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
2586                 goto failed_mount;
2587
2588         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2589
2590         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2591             blocksize > EXT4_MAX_BLOCK_SIZE) {
2592                 ext4_msg(sb, KERN_ERR,
2593                        "Unsupported filesystem blocksize %d", blocksize);
2594                 goto failed_mount;
2595         }
2596
2597         if (sb->s_blocksize != blocksize) {
2598                 /* Validate the filesystem blocksize */
2599                 if (!sb_set_blocksize(sb, blocksize)) {
2600                         ext4_msg(sb, KERN_ERR, "bad block size %d",
2601                                         blocksize);
2602                         goto failed_mount;
2603                 }
2604
2605                 brelse(bh);
2606                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2607                 offset = do_div(logical_sb_block, blocksize);
2608                 bh = sb_bread(sb, logical_sb_block);
2609                 if (!bh) {
2610                         ext4_msg(sb, KERN_ERR,
2611                                "Can't read superblock on 2nd try");
2612                         goto failed_mount;
2613                 }
2614                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2615                 sbi->s_es = es;
2616                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2617                         ext4_msg(sb, KERN_ERR,
2618                                "Magic mismatch, very weird!");
2619                         goto failed_mount;
2620                 }
2621         }
2622
2623         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
2624                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
2625         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
2626                                                       has_huge_files);
2627         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
2628
2629         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2630                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2631                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2632         } else {
2633                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2634                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2635                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2636                     (!is_power_of_2(sbi->s_inode_size)) ||
2637                     (sbi->s_inode_size > blocksize)) {
2638                         ext4_msg(sb, KERN_ERR,
2639                                "unsupported inode size: %d",
2640                                sbi->s_inode_size);
2641                         goto failed_mount;
2642                 }
2643                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2644                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2645         }
2646
2647         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2648         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2649                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2650                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2651                     !is_power_of_2(sbi->s_desc_size)) {
2652                         ext4_msg(sb, KERN_ERR,
2653                                "unsupported descriptor size %lu",
2654                                sbi->s_desc_size);
2655                         goto failed_mount;
2656                 }
2657         } else
2658                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2659
2660         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2661         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2662         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2663                 goto cantfind_ext4;
2664
2665         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2666         if (sbi->s_inodes_per_block == 0)
2667                 goto cantfind_ext4;
2668         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2669                                         sbi->s_inodes_per_block;
2670         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2671         sbi->s_sbh = bh;
2672         sbi->s_mount_state = le16_to_cpu(es->s_state);
2673         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2674         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2675
2676         for (i = 0; i < 4; i++)
2677                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2678         sbi->s_def_hash_version = es->s_def_hash_version;
2679         i = le32_to_cpu(es->s_flags);
2680         if (i & EXT2_FLAGS_UNSIGNED_HASH)
2681                 sbi->s_hash_unsigned = 3;
2682         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
2683 #ifdef __CHAR_UNSIGNED__
2684                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
2685                 sbi->s_hash_unsigned = 3;
2686 #else
2687                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
2688 #endif
2689                 sb->s_dirt = 1;
2690         }
2691
2692         if (sbi->s_blocks_per_group > blocksize * 8) {
2693                 ext4_msg(sb, KERN_ERR,
2694                        "#blocks per group too big: %lu",
2695                        sbi->s_blocks_per_group);
2696                 goto failed_mount;
2697         }
2698         if (sbi->s_inodes_per_group > blocksize * 8) {
2699                 ext4_msg(sb, KERN_ERR,
2700                        "#inodes per group too big: %lu",
2701                        sbi->s_inodes_per_group);
2702                 goto failed_mount;
2703         }
2704
2705         /*
2706          * Test whether we have more sectors than will fit in sector_t,
2707          * and whether the max offset is addressable by the page cache.
2708          */
2709         if ((ext4_blocks_count(es) >
2710              (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) ||
2711             (ext4_blocks_count(es) >
2712              (pgoff_t)(~0ULL) >> (PAGE_CACHE_SHIFT - sb->s_blocksize_bits))) {
2713                 ext4_msg(sb, KERN_ERR, "filesystem"
2714                          " too large to mount safely on this system");
2715                 if (sizeof(sector_t) < 8)
2716                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
2717                 ret = -EFBIG;
2718                 goto failed_mount;
2719         }
2720
2721         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2722                 goto cantfind_ext4;
2723
2724         /* check blocks count against device size */
2725         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
2726         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
2727                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
2728                        "exceeds size of device (%llu blocks)",
2729                        ext4_blocks_count(es), blocks_count);
2730                 goto failed_mount;
2731         }
2732
2733         /*
2734          * It makes no sense for the first data block to be beyond the end
2735          * of the filesystem.
2736          */
2737         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
2738                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data"
2739                          "block %u is beyond end of filesystem (%llu)",
2740                          le32_to_cpu(es->s_first_data_block),
2741                          ext4_blocks_count(es));
2742                 goto failed_mount;
2743         }
2744         blocks_count = (ext4_blocks_count(es) -
2745                         le32_to_cpu(es->s_first_data_block) +
2746                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2747         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2748         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
2749                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
2750                        "(block count %llu, first data block %u, "
2751                        "blocks per group %lu)", sbi->s_groups_count,
2752                        ext4_blocks_count(es),
2753                        le32_to_cpu(es->s_first_data_block),
2754                        EXT4_BLOCKS_PER_GROUP(sb));
2755                 goto failed_mount;
2756         }
2757         sbi->s_groups_count = blocks_count;
2758         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
2759                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
2760         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2761                    EXT4_DESC_PER_BLOCK(sb);
2762         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
2763                                     GFP_KERNEL);
2764         if (sbi->s_group_desc == NULL) {
2765                 ext4_msg(sb, KERN_ERR, "not enough memory");
2766                 goto failed_mount;
2767         }
2768
2769 #ifdef CONFIG_PROC_FS
2770         if (ext4_proc_root)
2771                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
2772 #endif
2773
2774         bgl_lock_init(sbi->s_blockgroup_lock);
2775
2776         for (i = 0; i < db_count; i++) {
2777                 block = descriptor_loc(sb, logical_sb_block, i);
2778                 sbi->s_group_desc[i] = sb_bread(sb, block);
2779                 if (!sbi->s_group_desc[i]) {
2780                         ext4_msg(sb, KERN_ERR,
2781                                "can't read group descriptor %d", i);
2782                         db_count = i;
2783                         goto failed_mount2;
2784                 }
2785         }
2786         if (!ext4_check_descriptors(sb)) {
2787                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
2788                 goto failed_mount2;
2789         }
2790         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2791                 if (!ext4_fill_flex_info(sb)) {
2792                         ext4_msg(sb, KERN_ERR,
2793                                "unable to initialize "
2794                                "flex_bg meta info!");
2795                         goto failed_mount2;
2796                 }
2797
2798         sbi->s_gdb_count = db_count;
2799         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2800         spin_lock_init(&sbi->s_next_gen_lock);
2801
2802         sbi->s_stripe = ext4_get_stripe_size(sbi);
2803         sbi->s_max_writeback_mb_bump = 128;
2804
2805         /*
2806          * set up enough so that it can read an inode
2807          */
2808         if (!test_opt(sb, NOLOAD) &&
2809             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
2810                 sb->s_op = &ext4_sops;
2811         else
2812                 sb->s_op = &ext4_nojournal_sops;
2813         sb->s_export_op = &ext4_export_ops;
2814         sb->s_xattr = ext4_xattr_handlers;
2815 #ifdef CONFIG_QUOTA
2816         sb->s_qcop = &ext4_qctl_operations;
2817         sb->dq_op = &ext4_quota_operations;
2818 #endif
2819         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2820         mutex_init(&sbi->s_orphan_lock);
2821         mutex_init(&sbi->s_resize_lock);
2822
2823         sb->s_root = NULL;
2824
2825         needs_recovery = (es->s_last_orphan != 0 ||
2826                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2827                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2828
2829         /*
2830          * The first inode we look at is the journal inode.  Don't try
2831          * root first: it may be modified in the journal!
2832          */
2833         if (!test_opt(sb, NOLOAD) &&
2834             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2835                 if (ext4_load_journal(sb, es, journal_devnum))
2836                         goto failed_mount3;
2837         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
2838               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2839                 ext4_msg(sb, KERN_ERR, "required journal recovery "
2840                        "suppressed and not mounted read-only");
2841                 goto failed_mount_wq;
2842         } else {
2843                 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
2844                 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
2845                 sbi->s_journal = NULL;
2846                 needs_recovery = 0;
2847                 goto no_journal;
2848         }
2849
2850         if (ext4_blocks_count(es) > 0xffffffffULL &&
2851             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2852                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
2853                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
2854                 goto failed_mount_wq;
2855         }
2856
2857         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2858                 jbd2_journal_set_features(sbi->s_journal,
2859                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2860                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2861         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2862                 jbd2_journal_set_features(sbi->s_journal,
2863                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2864                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2865                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2866         } else {
2867                 jbd2_journal_clear_features(sbi->s_journal,
2868                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2869                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2870         }
2871
2872         /* We have now updated the journal if required, so we can
2873          * validate the data journaling mode. */
2874         switch (test_opt(sb, DATA_FLAGS)) {
2875         case 0:
2876                 /* No mode set, assume a default based on the journal
2877                  * capabilities: ORDERED_DATA if the journal can
2878                  * cope, else JOURNAL_DATA
2879                  */
2880                 if (jbd2_journal_check_available_features
2881                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2882                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
2883                 else
2884                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2885                 break;
2886
2887         case EXT4_MOUNT_ORDERED_DATA:
2888         case EXT4_MOUNT_WRITEBACK_DATA:
2889                 if (!jbd2_journal_check_available_features
2890                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2891                         ext4_msg(sb, KERN_ERR, "Journal does not support "
2892                                "requested data journaling mode");
2893                         goto failed_mount_wq;
2894                 }
2895         default:
2896                 break;
2897         }
2898         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
2899
2900 no_journal:
2901         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2902                                   ext4_count_free_blocks(sb));
2903         if (!err)
2904                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2905                                           ext4_count_free_inodes(sb));
2906         if (!err)
2907                 err = percpu_counter_init(&sbi->s_dirs_counter,
2908                                           ext4_count_dirs(sb));
2909         if (!err)
2910                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
2911         if (err) {
2912                 ext4_msg(sb, KERN_ERR, "insufficient memory");
2913                 goto failed_mount_wq;
2914         }
2915
2916         EXT4_SB(sb)->dio_unwritten_wq = create_workqueue("ext4-dio-unwritten");
2917         if (!EXT4_SB(sb)->dio_unwritten_wq) {
2918                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
2919                 goto failed_mount_wq;
2920         }
2921
2922         /*
2923          * The jbd2_journal_load will have done any necessary log recovery,
2924          * so we can safely mount the rest of the filesystem now.
2925          */
2926
2927         root = ext4_iget(sb, EXT4_ROOT_INO);
2928         if (IS_ERR(root)) {
2929                 ext4_msg(sb, KERN_ERR, "get root inode failed");
2930                 ret = PTR_ERR(root);
2931                 goto failed_mount4;
2932         }
2933         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2934                 iput(root);
2935                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
2936                 goto failed_mount4;
2937         }
2938         sb->s_root = d_alloc_root(root);
2939         if (!sb->s_root) {
2940                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
2941                 iput(root);
2942                 ret = -ENOMEM;
2943                 goto failed_mount4;
2944         }
2945
2946         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
2947
2948         /* determine the minimum size of new large inodes, if present */
2949         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2950                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2951                                                      EXT4_GOOD_OLD_INODE_SIZE;
2952                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2953                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2954                         if (sbi->s_want_extra_isize <
2955                             le16_to_cpu(es->s_want_extra_isize))
2956                                 sbi->s_want_extra_isize =
2957                                         le16_to_cpu(es->s_want_extra_isize);
2958                         if (sbi->s_want_extra_isize <
2959                             le16_to_cpu(es->s_min_extra_isize))
2960                                 sbi->s_want_extra_isize =
2961                                         le16_to_cpu(es->s_min_extra_isize);
2962                 }
2963         }
2964         /* Check if enough inode space is available */
2965         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2966                                                         sbi->s_inode_size) {
2967                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2968                                                        EXT4_GOOD_OLD_INODE_SIZE;
2969                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
2970                          "available");
2971         }
2972
2973         if (test_opt(sb, DELALLOC) &&
2974             (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2975                 ext4_msg(sb, KERN_WARNING, "Ignoring delalloc option - "
2976                          "requested data journaling mode");
2977                 clear_opt(sbi->s_mount_opt, DELALLOC);
2978         }
2979         if (test_opt(sb, DIOREAD_NOLOCK)) {
2980                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
2981                         ext4_msg(sb, KERN_WARNING, "Ignoring dioread_nolock "
2982                                 "option - requested data journaling mode");
2983                         clear_opt(sbi->s_mount_opt, DIOREAD_NOLOCK);
2984                 }
2985                 if (sb->s_blocksize < PAGE_SIZE) {
2986                         ext4_msg(sb, KERN_WARNING, "Ignoring dioread_nolock "
2987                                 "option - block size is too small");
2988                         clear_opt(sbi->s_mount_opt, DIOREAD_NOLOCK);
2989                 }
2990         }
2991
2992         err = ext4_setup_system_zone(sb);
2993         if (err) {
2994                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
2995                          "zone (%d)", err);
2996                 goto failed_mount4;
2997         }
2998
2999         ext4_ext_init(sb);
3000         err = ext4_mb_init(sb, needs_recovery);
3001         if (err) {
3002                 ext4_msg(sb, KERN_ERR, "failed to initalize mballoc (%d)",
3003                          err);
3004                 goto failed_mount4;
3005         }
3006
3007         sbi->s_kobj.kset = ext4_kset;
3008         init_completion(&sbi->s_kobj_unregister);
3009         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
3010                                    "%s", sb->s_id);
3011         if (err) {
3012                 ext4_mb_release(sb);
3013                 ext4_ext_release(sb);
3014                 goto failed_mount4;
3015         };
3016
3017         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
3018         ext4_orphan_cleanup(sb, es);
3019         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
3020         if (needs_recovery) {
3021                 ext4_msg(sb, KERN_INFO, "recovery complete");
3022                 ext4_mark_recovery_complete(sb, es);
3023         }
3024         if (EXT4_SB(sb)->s_journal) {
3025                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3026                         descr = " journalled data mode";
3027                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3028                         descr = " ordered data mode";
3029                 else
3030                         descr = " writeback data mode";
3031         } else
3032                 descr = "out journal";
3033
3034         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
3035                 "Opts: %s", descr, orig_data);
3036
3037         lock_kernel();
3038         kfree(orig_data);
3039         return 0;
3040
3041 cantfind_ext4:
3042         if (!silent)
3043                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
3044         goto failed_mount;
3045
3046 failed_mount4:
3047         ext4_msg(sb, KERN_ERR, "mount failed");
3048         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
3049 failed_mount_wq:
3050         ext4_release_system_zone(sb);
3051         if (sbi->s_journal) {
3052                 jbd2_journal_destroy(sbi->s_journal);
3053                 sbi->s_journal = NULL;
3054         }
3055         percpu_counter_destroy(&sbi->s_freeblocks_counter);
3056         percpu_counter_destroy(&sbi->s_freeinodes_counter);
3057         percpu_counter_destroy(&sbi->s_dirs_counter);
3058         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
3059 failed_mount3:
3060         if (sbi->s_flex_groups) {
3061                 if (is_vmalloc_addr(sbi->s_flex_groups))
3062                         vfree(sbi->s_flex_groups);
3063                 else
3064                         kfree(sbi->s_flex_groups);
3065         }
3066 failed_mount2:
3067         for (i = 0; i < db_count; i++)
3068                 brelse(sbi->s_group_desc[i]);
3069         kfree(sbi->s_group_desc);
3070 failed_mount:
3071         if (sbi->s_proc) {
3072                 remove_proc_entry(sb->s_id, ext4_proc_root);
3073         }
3074 #ifdef CONFIG_QUOTA
3075         for (i = 0; i < MAXQUOTAS; i++)
3076                 kfree(sbi->s_qf_names[i]);
3077 #endif
3078         ext4_blkdev_remove(sbi);
3079         brelse(bh);
3080 out_fail:
3081         sb->s_fs_info = NULL;
3082         kfree(sbi->s_blockgroup_lock);
3083         kfree(sbi);
3084         lock_kernel();
3085         kfree(orig_data);
3086         return ret;
3087 }
3088
3089 /*
3090  * Setup any per-fs journal parameters now.  We'll do this both on
3091  * initial mount, once the journal has been initialised but before we've
3092  * done any recovery; and again on any subsequent remount.
3093  */
3094 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
3095 {
3096         struct ext4_sb_info *sbi = EXT4_SB(sb);
3097
3098         journal->j_commit_interval = sbi->s_commit_interval;
3099         journal->j_min_batch_time = sbi->s_min_batch_time;
3100         journal->j_max_batch_time = sbi->s_max_batch_time;
3101
3102         spin_lock(&journal->j_state_lock);
3103         if (test_opt(sb, BARRIER))
3104                 journal->j_flags |= JBD2_BARRIER;
3105         else
3106                 journal->j_flags &= ~JBD2_BARRIER;
3107         if (test_opt(sb, DATA_ERR_ABORT))
3108                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
3109         else
3110                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
3111         spin_unlock(&journal->j_state_lock);
3112 }
3113
3114 static journal_t *ext4_get_journal(struct super_block *sb,
3115                                    unsigned int journal_inum)
3116 {
3117         struct inode *journal_inode;
3118         journal_t *journal;
3119
3120         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3121
3122         /* First, test for the existence of a valid inode on disk.  Bad
3123          * things happen if we iget() an unused inode, as the subsequent
3124          * iput() will try to delete it. */
3125
3126         journal_inode = ext4_iget(sb, journal_inum);
3127         if (IS_ERR(journal_inode)) {
3128                 ext4_msg(sb, KERN_ERR, "no journal found");
3129                 return NULL;
3130         }
3131         if (!journal_inode->i_nlink) {
3132                 make_bad_inode(journal_inode);
3133                 iput(journal_inode);
3134                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
3135                 return NULL;
3136         }
3137
3138         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
3139                   journal_inode, journal_inode->i_size);
3140         if (!S_ISREG(journal_inode->i_mode)) {
3141                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
3142                 iput(journal_inode);
3143                 return NULL;
3144         }
3145
3146         journal = jbd2_journal_init_inode(journal_inode);
3147         if (!journal) {
3148                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
3149                 iput(journal_inode);
3150                 return NULL;
3151         }
3152         journal->j_private = sb;
3153         ext4_init_journal_params(sb, journal);
3154         return journal;
3155 }
3156
3157 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3158                                        dev_t j_dev)
3159 {
3160         struct buffer_head *bh;
3161         journal_t *journal;
3162         ext4_fsblk_t start;
3163         ext4_fsblk_t len;
3164         int hblock, blocksize;
3165         ext4_fsblk_t sb_block;
3166         unsigned long offset;
3167         struct ext4_super_block *es;
3168         struct block_device *bdev;
3169
3170         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3171
3172         bdev = ext4_blkdev_get(j_dev, sb);
3173         if (bdev == NULL)
3174                 return NULL;
3175
3176         if (bd_claim(bdev, sb)) {
3177                 ext4_msg(sb, KERN_ERR,
3178                         "failed to claim external journal device");
3179                 blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
3180                 return NULL;
3181         }
3182
3183         blocksize = sb->s_blocksize;
3184         hblock = bdev_logical_block_size(bdev);
3185         if (blocksize < hblock) {
3186                 ext4_msg(sb, KERN_ERR,
3187                         "blocksize too small for journal device");
3188                 goto out_bdev;
3189         }
3190
3191         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3192         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3193         set_blocksize(bdev, blocksize);
3194         if (!(bh = __bread(bdev, sb_block, blocksize))) {
3195                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
3196                        "external journal");
3197                 goto out_bdev;
3198         }
3199
3200         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3201         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
3202             !(le32_to_cpu(es->s_feature_incompat) &
3203               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
3204                 ext4_msg(sb, KERN_ERR, "external journal has "
3205                                         "bad superblock");
3206                 brelse(bh);
3207                 goto out_bdev;
3208         }
3209
3210         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
3211                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
3212                 brelse(bh);
3213                 goto out_bdev;
3214         }
3215
3216         len = ext4_blocks_count(es);
3217         start = sb_block + 1;
3218         brelse(bh);     /* we're done with the superblock */
3219
3220         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
3221                                         start, len, blocksize);
3222         if (!journal) {
3223                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
3224                 goto out_bdev;
3225         }
3226         journal->j_private = sb;
3227         ll_rw_block(READ, 1, &journal->j_sb_buffer);
3228         wait_on_buffer(journal->j_sb_buffer);
3229         if (!buffer_uptodate(journal->j_sb_buffer)) {
3230                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
3231                 goto out_journal;
3232         }
3233         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
3234                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
3235                                         "user (unsupported) - %d",
3236                         be32_to_cpu(journal->j_superblock->s_nr_users));
3237                 goto out_journal;
3238         }
3239         EXT4_SB(sb)->journal_bdev = bdev;
3240         ext4_init_journal_params(sb, journal);
3241         return journal;
3242
3243 out_journal:
3244         jbd2_journal_destroy(journal);
3245 out_bdev:
3246         ext4_blkdev_put(bdev);
3247         return NULL;
3248 }
3249
3250 static int ext4_load_journal(struct super_block *sb,
3251                              struct ext4_super_block *es,
3252                              unsigned long journal_devnum)
3253 {
3254         journal_t *journal;
3255         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
3256         dev_t journal_dev;
3257         int err = 0;
3258         int really_read_only;
3259
3260         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3261
3262         if (journal_devnum &&
3263             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3264                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
3265                         "numbers have changed");
3266                 journal_dev = new_decode_dev(journal_devnum);
3267         } else
3268                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
3269
3270         really_read_only = bdev_read_only(sb->s_bdev);
3271
3272         /*
3273          * Are we loading a blank journal or performing recovery after a
3274          * crash?  For recovery, we need to check in advance whether we
3275          * can get read-write access to the device.
3276          */
3277         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3278                 if (sb->s_flags & MS_RDONLY) {
3279                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
3280                                         "required on readonly filesystem");
3281                         if (really_read_only) {
3282                                 ext4_msg(sb, KERN_ERR, "write access "
3283                                         "unavailable, cannot proceed");
3284                                 return -EROFS;
3285                         }
3286                         ext4_msg(sb, KERN_INFO, "write access will "
3287                                "be enabled during recovery");
3288                 }
3289         }
3290
3291         if (journal_inum && journal_dev) {
3292                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
3293                        "and inode journals!");
3294                 return -EINVAL;
3295         }
3296
3297         if (journal_inum) {
3298                 if (!(journal = ext4_get_journal(sb, journal_inum)))
3299                         return -EINVAL;
3300         } else {
3301                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
3302                         return -EINVAL;
3303         }
3304
3305         if (!(journal->j_flags & JBD2_BARRIER))
3306                 ext4_msg(sb, KERN_INFO, "barriers disabled");
3307
3308         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
3309                 err = jbd2_journal_update_format(journal);
3310                 if (err)  {
3311                         ext4_msg(sb, KERN_ERR, "error updating journal");
3312                         jbd2_journal_destroy(journal);
3313                         return err;
3314                 }
3315         }
3316
3317         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
3318                 err = jbd2_journal_wipe(journal, !really_read_only);
3319         if (!err)
3320                 err = jbd2_journal_load(journal);
3321
3322         if (err) {
3323                 ext4_msg(sb, KERN_ERR, "error loading journal");
3324                 jbd2_journal_destroy(journal);
3325                 return err;
3326         }
3327
3328         EXT4_SB(sb)->s_journal = journal;
3329         ext4_clear_journal_err(sb, es);
3330
3331         if (journal_devnum &&
3332             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3333                 es->s_journal_dev = cpu_to_le32(journal_devnum);
3334
3335                 /* Make sure we flush the recovery flag to disk. */
3336                 ext4_commit_super(sb, 1);
3337         }
3338
3339         return 0;
3340 }
3341
3342 static int ext4_commit_super(struct super_block *sb, int sync)
3343 {
3344         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
3345         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
3346         int error = 0;
3347
3348         if (!sbh)
3349                 return error;
3350         if (buffer_write_io_error(sbh)) {
3351                 /*
3352                  * Oh, dear.  A previous attempt to write the
3353                  * superblock failed.  This could happen because the
3354                  * USB device was yanked out.  Or it could happen to
3355                  * be a transient write error and maybe the block will
3356                  * be remapped.  Nothing we can do but to retry the
3357                  * write and hope for the best.
3358                  */
3359                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
3360                        "superblock detected");
3361                 clear_buffer_write_io_error(sbh);
3362                 set_buffer_uptodate(sbh);
3363         }
3364         /*
3365          * If the file system is mounted read-only, don't update the
3366          * superblock write time.  This avoids updating the superblock
3367          * write time when we are mounting the root file system
3368          * read/only but we need to replay the journal; at that point,
3369          * for people who are east of GMT and who make their clock
3370          * tick in localtime for Windows bug-for-bug compatibility,
3371          * the clock is set in the future, and this will cause e2fsck
3372          * to complain and force a full file system check.
3373          */
3374         if (!(sb->s_flags & MS_RDONLY))
3375                 es->s_wtime = cpu_to_le32(get_seconds());
3376         es->s_kbytes_written =
3377                 cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
3378                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
3379                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
3380         ext4_free_blocks_count_set(es, percpu_counter_sum_positive(
3381                                         &EXT4_SB(sb)->s_freeblocks_counter));
3382         es->s_free_inodes_count = cpu_to_le32(percpu_counter_sum_positive(
3383                                         &EXT4_SB(sb)->s_freeinodes_counter));
3384         sb->s_dirt = 0;
3385         BUFFER_TRACE(sbh, "marking dirty");
3386         mark_buffer_dirty(sbh);
3387         if (sync) {
3388                 error = sync_dirty_buffer(sbh);
3389                 if (error)
3390                         return error;
3391
3392                 error = buffer_write_io_error(sbh);
3393                 if (error) {
3394                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
3395                                "superblock");
3396                         clear_buffer_write_io_error(sbh);
3397                         set_buffer_uptodate(sbh);
3398                 }
3399         }
3400         return error;
3401 }
3402
3403 /*
3404  * Have we just finished recovery?  If so, and if we are mounting (or
3405  * remounting) the filesystem readonly, then we will end up with a
3406  * consistent fs on disk.  Record that fact.
3407  */
3408 static void ext4_mark_recovery_complete(struct super_block *sb,
3409                                         struct ext4_super_block *es)
3410 {
3411         journal_t *journal = EXT4_SB(sb)->s_journal;
3412
3413         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3414                 BUG_ON(journal != NULL);
3415                 return;
3416         }
3417         jbd2_journal_lock_updates(journal);
3418         if (jbd2_journal_flush(journal) < 0)
3419                 goto out;
3420
3421         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
3422             sb->s_flags & MS_RDONLY) {
3423                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3424                 ext4_commit_super(sb, 1);
3425         }
3426
3427 out:
3428         jbd2_journal_unlock_updates(journal);
3429 }
3430
3431 /*
3432  * If we are mounting (or read-write remounting) a filesystem whose journal
3433  * has recorded an error from a previous lifetime, move that error to the
3434  * main filesystem now.
3435  */
3436 static void ext4_clear_journal_err(struct super_block *sb,
3437                                    struct ext4_super_block *es)
3438 {
3439         journal_t *journal;
3440         int j_errno;
3441         const char *errstr;
3442
3443         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3444
3445         journal = EXT4_SB(sb)->s_journal;
3446
3447         /*
3448          * Now check for any error status which may have been recorded in the
3449          * journal by a prior ext4_error() or ext4_abort()
3450          */
3451
3452         j_errno = jbd2_journal_errno(journal);
3453         if (j_errno) {
3454                 char nbuf[16];
3455
3456                 errstr = ext4_decode_error(sb, j_errno, nbuf);
3457                 ext4_warning(sb, "Filesystem error recorded "
3458                              "from previous mount: %s", errstr);
3459                 ext4_warning(sb, "Marking fs in need of filesystem check.");
3460
3461                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
3462                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
3463                 ext4_commit_super(sb, 1);
3464
3465                 jbd2_journal_clear_err(journal);
3466         }
3467 }
3468
3469 /*
3470  * Force the running and committing transactions to commit,
3471  * and wait on the commit.
3472  */
3473 int ext4_force_commit(struct super_block *sb)
3474 {
3475         journal_t *journal;
3476         int ret = 0;
3477
3478         if (sb->s_flags & MS_RDONLY)
3479                 return 0;
3480
3481         journal = EXT4_SB(sb)->s_journal;
3482         if (journal) {
3483                 vfs_check_frozen(sb, SB_FREEZE_WRITE);
3484                 ret = ext4_journal_force_commit(journal);
3485         }
3486
3487         return ret;
3488 }
3489
3490 static void ext4_write_super(struct super_block *sb)
3491 {
3492         lock_super(sb);
3493         ext4_commit_super(sb, 1);
3494         unlock_super(sb);
3495 }
3496
3497 static int ext4_sync_fs(struct super_block *sb, int wait)
3498 {
3499         int ret = 0;
3500         tid_t target;
3501         struct ext4_sb_info *sbi = EXT4_SB(sb);
3502
3503         trace_ext4_sync_fs(sb, wait);
3504         flush_workqueue(sbi->dio_unwritten_wq);
3505         if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
3506                 if (wait)
3507                         jbd2_log_wait_commit(sbi->s_journal, target);
3508         }
3509         return ret;
3510 }
3511
3512 /*
3513  * LVM calls this function before a (read-only) snapshot is created.  This
3514  * gives us a chance to flush the journal completely and mark the fs clean.
3515  */
3516 static int ext4_freeze(struct super_block *sb)
3517 {
3518         int error = 0;
3519         journal_t *journal;
3520
3521         if (sb->s_flags & MS_RDONLY)
3522                 return 0;
3523
3524         journal = EXT4_SB(sb)->s_journal;
3525
3526         /* Now we set up the journal barrier. */
3527         jbd2_journal_lock_updates(journal);
3528
3529         /*
3530          * Don't clear the needs_recovery flag if we failed to flush
3531          * the journal.
3532          */
3533         error = jbd2_journal_flush(journal);
3534         if (error < 0)
3535                 goto out;
3536
3537         /* Journal blocked and flushed, clear needs_recovery flag. */
3538         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3539         error = ext4_commit_super(sb, 1);
3540 out:
3541         /* we rely on s_frozen to stop further updates */
3542         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3543         return error;
3544 }
3545
3546 /*
3547  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
3548  * flag here, even though the filesystem is not technically dirty yet.
3549  */
3550 static int ext4_unfreeze(struct super_block *sb)
3551 {
3552         if (sb->s_flags & MS_RDONLY)
3553                 return 0;
3554
3555         lock_super(sb);
3556         /* Reset the needs_recovery flag before the fs is unlocked. */
3557         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3558         ext4_commit_super(sb, 1);
3559         unlock_super(sb);
3560         return 0;
3561 }
3562
3563 static int ext4_remount(struct super_block *sb, int *flags, char *data)
3564 {
3565         struct ext4_super_block *es;
3566         struct ext4_sb_info *sbi = EXT4_SB(sb);
3567         ext4_fsblk_t n_blocks_count = 0;
3568         unsigned long old_sb_flags;
3569         struct ext4_mount_options old_opts;
3570         int enable_quota = 0;
3571         ext4_group_t g;
3572         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3573         int err;
3574 #ifdef CONFIG_QUOTA
3575         int i;
3576 #endif
3577         char *orig_data = kstrdup(data, GFP_KERNEL);
3578
3579         lock_kernel();
3580
3581         /* Store the original options */
3582         lock_super(sb);
3583         old_sb_flags = sb->s_flags;
3584         old_opts.s_mount_opt = sbi->s_mount_opt;
3585         old_opts.s_resuid = sbi->s_resuid;
3586         old_opts.s_resgid = sbi->s_resgid;
3587         old_opts.s_commit_interval = sbi->s_commit_interval;
3588         old_opts.s_min_batch_time = sbi->s_min_batch_time;
3589         old_opts.s_max_batch_time = sbi->s_max_batch_time;
3590 #ifdef CONFIG_QUOTA
3591         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
3592         for (i = 0; i < MAXQUOTAS; i++)
3593                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
3594 #endif
3595         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
3596                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
3597
3598         /*
3599          * Allow the "check" option to be passed as a remount option.
3600          */
3601         if (!parse_options(data, sb, NULL, &journal_ioprio,
3602                            &n_blocks_count, 1)) {
3603                 err = -EINVAL;
3604                 goto restore_opts;
3605         }
3606
3607         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
3608                 ext4_abort(sb, __func__, "Abort forced by user");
3609
3610         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3611                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3612
3613         es = sbi->s_es;
3614
3615         if (sbi->s_journal) {
3616                 ext4_init_journal_params(sb, sbi->s_journal);
3617                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3618         }
3619
3620         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
3621                 n_blocks_count > ext4_blocks_count(es)) {
3622                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
3623                         err = -EROFS;
3624                         goto restore_opts;
3625                 }
3626
3627                 if (*flags & MS_RDONLY) {
3628                         err = dquot_suspend(sb, -1);
3629                         if (err < 0)
3630                                 goto restore_opts;
3631
3632                         /*
3633                          * First of all, the unconditional stuff we have to do
3634                          * to disable replay of the journal when we next remount
3635                          */
3636                         sb->s_flags |= MS_RDONLY;
3637
3638                         /*
3639                          * OK, test if we are remounting a valid rw partition
3640                          * readonly, and if so set the rdonly flag and then
3641                          * mark the partition as valid again.
3642                          */
3643                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
3644                             (sbi->s_mount_state & EXT4_VALID_FS))
3645                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
3646
3647                         if (sbi->s_journal)
3648                                 ext4_mark_recovery_complete(sb, es);
3649                 } else {
3650                         /* Make sure we can mount this feature set readwrite */
3651                         if (!ext4_feature_set_ok(sb, 0)) {
3652                                 err = -EROFS;
3653                                 goto restore_opts;
3654                         }
3655                         /*
3656                          * Make sure the group descriptor checksums
3657                          * are sane.  If they aren't, refuse to remount r/w.
3658                          */
3659                         for (g = 0; g < sbi->s_groups_count; g++) {
3660                                 struct ext4_group_desc *gdp =
3661                                         ext4_get_group_desc(sb, g, NULL);
3662
3663                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
3664                                         ext4_msg(sb, KERN_ERR,
3665                "ext4_remount: Checksum for group %u failed (%u!=%u)",
3666                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
3667                                                le16_to_cpu(gdp->bg_checksum));
3668                                         err = -EINVAL;
3669                                         goto restore_opts;
3670                                 }
3671                         }
3672
3673                         /*
3674                          * If we have an unprocessed orphan list hanging
3675                          * around from a previously readonly bdev mount,
3676                          * require a full umount/remount for now.
3677                          */
3678                         if (es->s_last_orphan) {
3679                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
3680                                        "remount RDWR because of unprocessed "
3681                                        "orphan inode list.  Please "
3682                                        "umount/remount instead");
3683                                 err = -EINVAL;
3684                                 goto restore_opts;
3685                         }
3686
3687                         /*
3688                          * Mounting a RDONLY partition read-write, so reread
3689                          * and store the current valid flag.  (It may have
3690                          * been changed by e2fsck since we originally mounted
3691                          * the partition.)
3692                          */
3693                         if (sbi->s_journal)
3694                                 ext4_clear_journal_err(sb, es);
3695                         sbi->s_mount_state = le16_to_cpu(es->s_state);
3696                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
3697                                 goto restore_opts;
3698                         if (!ext4_setup_super(sb, es, 0))
3699                                 sb->s_flags &= ~MS_RDONLY;
3700                         enable_quota = 1;
3701                 }
3702         }
3703         ext4_setup_system_zone(sb);
3704         if (sbi->s_journal == NULL)
3705                 ext4_commit_super(sb, 1);
3706
3707 #ifdef CONFIG_QUOTA
3708         /* Release old quota file names */
3709         for (i = 0; i < MAXQUOTAS; i++)
3710                 if (old_opts.s_qf_names[i] &&
3711                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3712                         kfree(old_opts.s_qf_names[i]);
3713 #endif
3714         unlock_super(sb);
3715         unlock_kernel();
3716         if (enable_quota)
3717                 dquot_resume(sb, -1);
3718
3719         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
3720         kfree(orig_data);
3721         return 0;
3722
3723 restore_opts:
3724         sb->s_flags = old_sb_flags;
3725         sbi->s_mount_opt = old_opts.s_mount_opt;
3726         sbi->s_resuid = old_opts.s_resuid;
3727         sbi->s_resgid = old_opts.s_resgid;
3728         sbi->s_commit_interval = old_opts.s_commit_interval;
3729         sbi->s_min_batch_time = old_opts.s_min_batch_time;
3730         sbi->s_max_batch_time = old_opts.s_max_batch_time;
3731 #ifdef CONFIG_QUOTA
3732         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
3733         for (i = 0; i < MAXQUOTAS; i++) {
3734                 if (sbi->s_qf_names[i] &&
3735                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3736                         kfree(sbi->s_qf_names[i]);
3737                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
3738         }
3739 #endif
3740         unlock_super(sb);
3741         unlock_kernel();
3742         kfree(orig_data);
3743         return err;
3744 }
3745
3746 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
3747 {
3748         struct super_block *sb = dentry->d_sb;
3749         struct ext4_sb_info *sbi = EXT4_SB(sb);
3750         struct ext4_super_block *es = sbi->s_es;
3751         u64 fsid;
3752
3753         if (test_opt(sb, MINIX_DF)) {
3754                 sbi->s_overhead_last = 0;
3755         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
3756                 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3757                 ext4_fsblk_t overhead = 0;
3758
3759                 /*
3760                  * Compute the overhead (FS structures).  This is constant
3761                  * for a given filesystem unless the number of block groups
3762                  * changes so we cache the previous value until it does.
3763                  */
3764
3765                 /*
3766                  * All of the blocks before first_data_block are
3767                  * overhead
3768                  */
3769                 overhead = le32_to_cpu(es->s_first_data_block);
3770
3771                 /*
3772                  * Add the overhead attributed to the superblock and
3773                  * block group descriptors.  If the sparse superblocks
3774                  * feature is turned on, then not all groups have this.
3775                  */
3776                 for (i = 0; i < ngroups; i++) {
3777                         overhead += ext4_bg_has_super(sb, i) +
3778                                 ext4_bg_num_gdb(sb, i);
3779                         cond_resched();
3780                 }
3781
3782                 /*
3783                  * Every block group has an inode bitmap, a block
3784                  * bitmap, and an inode table.
3785                  */
3786                 overhead += ngroups * (2 + sbi->s_itb_per_group);
3787                 sbi->s_overhead_last = overhead;
3788                 smp_wmb();
3789                 sbi->s_blocks_last = ext4_blocks_count(es);
3790         }
3791
3792         buf->f_type = EXT4_SUPER_MAGIC;
3793         buf->f_bsize = sb->s_blocksize;
3794         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
3795         buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
3796                        percpu_counter_sum_positive(&sbi->s_dirtyblocks_counter);
3797         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
3798         if (buf->f_bfree < ext4_r_blocks_count(es))
3799                 buf->f_bavail = 0;
3800         buf->f_files = le32_to_cpu(es->s_inodes_count);
3801         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
3802         buf->f_namelen = EXT4_NAME_LEN;
3803         fsid = le64_to_cpup((void *)es->s_uuid) ^
3804                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
3805         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
3806         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
3807
3808         return 0;
3809 }
3810
3811 /* Helper function for writing quotas on sync - we need to start transaction
3812  * before quota file is locked for write. Otherwise the are possible deadlocks:
3813  * Process 1                         Process 2
3814  * ext4_create()                     quota_sync()
3815  *   jbd2_journal_start()                  write_dquot()
3816  *   dquot_initialize()                         down(dqio_mutex)
3817  *     down(dqio_mutex)                    jbd2_journal_start()
3818  *
3819  */
3820
3821 #ifdef CONFIG_QUOTA
3822
3823 static inline struct inode *dquot_to_inode(struct dquot *dquot)
3824 {
3825         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
3826 }
3827
3828 static int ext4_write_dquot(struct dquot *dquot)
3829 {
3830         int ret, err;
3831         handle_t *handle;
3832         struct inode *inode;
3833
3834         inode = dquot_to_inode(dquot);
3835         handle = ext4_journal_start(inode,
3836                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
3837         if (IS_ERR(handle))
3838                 return PTR_ERR(handle);
3839         ret = dquot_commit(dquot);
3840         err = ext4_journal_stop(handle);
3841         if (!ret)
3842                 ret = err;
3843         return ret;
3844 }
3845
3846 static int ext4_acquire_dquot(struct dquot *dquot)
3847 {
3848         int ret, err;
3849         handle_t *handle;
3850
3851         handle = ext4_journal_start(dquot_to_inode(dquot),
3852                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
3853         if (IS_ERR(handle))
3854                 return PTR_ERR(handle);
3855         ret = dquot_acquire(dquot);
3856         err = ext4_journal_stop(handle);
3857         if (!ret)
3858                 ret = err;
3859         return ret;
3860 }
3861
3862 static int ext4_release_dquot(struct dquot *dquot)
3863 {
3864         int ret, err;
3865         handle_t *handle;
3866
3867         handle = ext4_journal_start(dquot_to_inode(dquot),
3868                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
3869         if (IS_ERR(handle)) {
3870                 /* Release dquot anyway to avoid endless cycle in dqput() */
3871                 dquot_release(dquot);
3872                 return PTR_ERR(handle);
3873         }
3874         ret = dquot_release(dquot);
3875         err = ext4_journal_stop(handle);
3876         if (!ret)
3877                 ret = err;
3878         return ret;
3879 }
3880
3881 static int ext4_mark_dquot_dirty(struct dquot *dquot)
3882 {
3883         /* Are we journaling quotas? */
3884         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
3885             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
3886                 dquot_mark_dquot_dirty(dquot);
3887                 return ext4_write_dquot(dquot);
3888         } else {
3889                 return dquot_mark_dquot_dirty(dquot);
3890         }
3891 }
3892
3893 static int ext4_write_info(struct super_block *sb, int type)
3894 {
3895         int ret, err;
3896         handle_t *handle;
3897
3898         /* Data block + inode block */
3899         handle = ext4_journal_start(sb->s_root->d_inode, 2);
3900         if (IS_ERR(handle))
3901                 return PTR_ERR(handle);
3902         ret = dquot_commit_info(sb, type);
3903         err = ext4_journal_stop(handle);
3904         if (!ret)
3905                 ret = err;
3906         return ret;
3907 }
3908
3909 /*
3910  * Turn on quotas during mount time - we need to find
3911  * the quota file and such...
3912  */
3913 static int ext4_quota_on_mount(struct super_block *sb, int type)
3914 {
3915         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
3916                                         EXT4_SB(sb)->s_jquota_fmt, type);
3917 }
3918
3919 /*
3920  * Standard function to be called on quota_on
3921  */
3922 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
3923                          char *name)
3924 {
3925         int err;
3926         struct path path;
3927
3928         if (!test_opt(sb, QUOTA))
3929                 return -EINVAL;
3930
3931         err = kern_path(name, LOOKUP_FOLLOW, &path);
3932         if (err)
3933                 return err;
3934
3935         /* Quotafile not on the same filesystem? */
3936         if (path.mnt->mnt_sb != sb) {
3937                 path_put(&path);
3938                 return -EXDEV;
3939         }
3940         /* Journaling quota? */
3941         if (EXT4_SB(sb)->s_qf_names[type]) {
3942                 /* Quotafile not in fs root? */
3943                 if (path.dentry->d_parent != sb->s_root)
3944                         ext4_msg(sb, KERN_WARNING,
3945                                 "Quota file not on filesystem root. "
3946                                 "Journaled quota will not work");
3947         }
3948
3949         /*
3950          * When we journal data on quota file, we have to flush journal to see
3951          * all updates to the file when we bypass pagecache...
3952          */
3953         if (EXT4_SB(sb)->s_journal &&
3954             ext4_should_journal_data(path.dentry->d_inode)) {
3955                 /*
3956                  * We don't need to lock updates but journal_flush() could
3957                  * otherwise be livelocked...
3958                  */
3959                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
3960                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
3961                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3962                 if (err) {
3963                         path_put(&path);
3964                         return err;
3965                 }
3966         }
3967
3968         err = dquot_quota_on_path(sb, type, format_id, &path);
3969         path_put(&path);
3970         return err;
3971 }
3972
3973 /* Read data from quotafile - avoid pagecache and such because we cannot afford
3974  * acquiring the locks... As quota files are never truncated and quota code
3975  * itself serializes the operations (and noone else should touch the files)
3976  * we don't have to be afraid of races */
3977 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
3978                                size_t len, loff_t off)
3979 {
3980         struct inode *inode = sb_dqopt(sb)->files[type];
3981         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3982         int err = 0;
3983         int offset = off & (sb->s_blocksize - 1);
3984         int tocopy;
3985         size_t toread;
3986         struct buffer_head *bh;
3987         loff_t i_size = i_size_read(inode);
3988
3989         if (off > i_size)
3990                 return 0;
3991         if (off+len > i_size)
3992                 len = i_size-off;
3993         toread = len;
3994         while (toread > 0) {
3995                 tocopy = sb->s_blocksize - offset < toread ?
3996                                 sb->s_blocksize - offset : toread;
3997                 bh = ext4_bread(NULL, inode, blk, 0, &err);
3998                 if (err)
3999                         return err;
4000                 if (!bh)        /* A hole? */
4001                         memset(data, 0, tocopy);
4002                 else
4003                         memcpy(data, bh->b_data+offset, tocopy);
4004                 brelse(bh);
4005                 offset = 0;
4006                 toread -= tocopy;
4007                 data += tocopy;
4008                 blk++;
4009         }
4010         return len;
4011 }
4012
4013 /* Write to quotafile (we know the transaction is already started and has
4014  * enough credits) */
4015 static ssize_t ext4_quota_write(struct super_block *sb, int type,
4016                                 const char *data, size_t len, loff_t off)
4017 {
4018         struct inode *inode = sb_dqopt(sb)->files[type];
4019         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4020         int err = 0;
4021         int offset = off & (sb->s_blocksize - 1);
4022         int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
4023         struct buffer_head *bh;
4024         handle_t *handle = journal_current_handle();
4025
4026         if (EXT4_SB(sb)->s_journal && !handle) {
4027                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4028                         " cancelled because transaction is not started",
4029                         (unsigned long long)off, (unsigned long long)len);
4030                 return -EIO;
4031         }
4032         /*
4033          * Since we account only one data block in transaction credits,
4034          * then it is impossible to cross a block boundary.
4035          */
4036         if (sb->s_blocksize - offset < len) {
4037                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4038                         " cancelled because not block aligned",
4039                         (unsigned long long)off, (unsigned long long)len);
4040                 return -EIO;
4041         }
4042
4043         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
4044         bh = ext4_bread(handle, inode, blk, 1, &err);
4045         if (!bh)
4046                 goto out;
4047         if (journal_quota) {
4048                 err = ext4_journal_get_write_access(handle, bh);
4049                 if (err) {
4050                         brelse(bh);
4051                         goto out;
4052                 }
4053         }
4054         lock_buffer(bh);
4055         memcpy(bh->b_data+offset, data, len);
4056         flush_dcache_page(bh->b_page);
4057         unlock_buffer(bh);
4058         if (journal_quota)
4059                 err = ext4_handle_dirty_metadata(handle, NULL, bh);
4060         else {
4061                 /* Always do at least ordered writes for quotas */
4062                 err = ext4_jbd2_file_inode(handle, inode);
4063                 mark_buffer_dirty(bh);
4064         }
4065         brelse(bh);
4066 out:
4067         if (err) {
4068                 mutex_unlock(&inode->i_mutex);
4069                 return err;
4070         }
4071         if (inode->i_size < off + len) {
4072                 i_size_write(inode, off + len);
4073                 EXT4_I(inode)->i_disksize = inode->i_size;
4074         }
4075         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
4076         ext4_mark_inode_dirty(handle, inode);
4077         mutex_unlock(&inode->i_mutex);
4078         return len;
4079 }
4080
4081 #endif
4082
4083 static int ext4_get_sb(struct file_system_type *fs_type, int flags,
4084                        const char *dev_name, void *data, struct vfsmount *mnt)
4085 {
4086         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super,mnt);
4087 }
4088
4089 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4090 static struct file_system_type ext2_fs_type = {
4091         .owner          = THIS_MODULE,
4092         .name           = "ext2",
4093         .get_sb         = ext4_get_sb,
4094         .kill_sb        = kill_block_super,
4095         .fs_flags       = FS_REQUIRES_DEV,
4096 };
4097
4098 static inline void register_as_ext2(void)
4099 {
4100         int err = register_filesystem(&ext2_fs_type);
4101         if (err)
4102                 printk(KERN_WARNING
4103                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
4104 }
4105
4106 static inline void unregister_as_ext2(void)
4107 {
4108         unregister_filesystem(&ext2_fs_type);
4109 }
4110 MODULE_ALIAS("ext2");
4111 #else
4112 static inline void register_as_ext2(void) { }
4113 static inline void unregister_as_ext2(void) { }
4114 #endif
4115
4116 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4117 static inline void register_as_ext3(void)
4118 {
4119         int err = register_filesystem(&ext3_fs_type);
4120         if (err)
4121                 printk(KERN_WARNING
4122                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
4123 }
4124
4125 static inline void unregister_as_ext3(void)
4126 {
4127         unregister_filesystem(&ext3_fs_type);
4128 }
4129 MODULE_ALIAS("ext3");
4130 #else
4131 static inline void register_as_ext3(void) { }
4132 static inline void unregister_as_ext3(void) { }
4133 #endif
4134
4135 static struct file_system_type ext4_fs_type = {
4136         .owner          = THIS_MODULE,
4137         .name           = "ext4",
4138         .get_sb         = ext4_get_sb,
4139         .kill_sb        = kill_block_super,
4140         .fs_flags       = FS_REQUIRES_DEV,
4141 };
4142
4143 static int __init init_ext4_fs(void)
4144 {
4145         int err;
4146
4147         ext4_check_flag_values();
4148         err = init_ext4_system_zone();
4149         if (err)
4150                 return err;
4151         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
4152         if (!ext4_kset)
4153                 goto out4;
4154         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
4155         err = init_ext4_mballoc();
4156         if (err)
4157                 goto out3;
4158
4159         err = init_ext4_xattr();
4160         if (err)
4161                 goto out2;
4162         err = init_inodecache();
4163         if (err)
4164                 goto out1;
4165         register_as_ext2();
4166         register_as_ext3();
4167         err = register_filesystem(&ext4_fs_type);
4168         if (err)
4169                 goto out;
4170         return 0;
4171 out:
4172         unregister_as_ext2();
4173         unregister_as_ext3();
4174         destroy_inodecache();
4175 out1:
4176         exit_ext4_xattr();
4177 out2:
4178         exit_ext4_mballoc();
4179 out3:
4180         remove_proc_entry("fs/ext4", NULL);
4181         kset_unregister(ext4_kset);
4182 out4:
4183         exit_ext4_system_zone();
4184         return err;
4185 }
4186
4187 static void __exit exit_ext4_fs(void)
4188 {
4189         unregister_as_ext2();
4190         unregister_as_ext3();
4191         unregister_filesystem(&ext4_fs_type);
4192         destroy_inodecache();
4193         exit_ext4_xattr();
4194         exit_ext4_mballoc();
4195         remove_proc_entry("fs/ext4", NULL);
4196         kset_unregister(ext4_kset);
4197         exit_ext4_system_zone();
4198 }
4199
4200 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
4201 MODULE_DESCRIPTION("Fourth Extended Filesystem");
4202 MODULE_LICENSE("GPL");
4203 module_init(init_ext4_fs)
4204 module_exit(exit_ext4_fs)