fs/ext4/super.c

   1 /*
   2  *  linux/fs/ext4/super.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/inode.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Big-endian to little-endian byte-swapping/bitmaps by
  16  *        David S. Miller (davem@caip.rutgers.edu), 1995
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/string.h>
  21 #include <linux/fs.h>
  22 #include <linux/time.h>
  23 #include <linux/vmalloc.h>
  24 #include <linux/jbd2.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/parser.h>
  29 #include <linux/buffer_head.h>
  30 #include <linux/exportfs.h>
  31 #include <linux/vfs.h>
  32 #include <linux/random.h>
  33 #include <linux/mount.h>
  34 #include <linux/namei.h>
  35 #include <linux/quotaops.h>
  36 #include <linux/seq_file.h>
  37 #include <linux/proc_fs.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <asm/uaccess.h>
  42
  43 #include <linux/kthread.h>
  44 #include <linux/freezer.h>
  45
  46 #include "ext4.h"
  47 #include "ext4_jbd2.h"
  48 #include "xattr.h"
  49 #include "acl.h"
  50 #include "mballoc.h"
  51
  52 #define CREATE_TRACE_POINTS
  53 #include <trace/events/ext4.h>
  54
  55 static struct proc_dir_entry *ext4_proc_root;
  56 static struct kset *ext4_kset;
  57 static struct ext4_lazy_init *ext4_li_info;
  58 static struct mutex ext4_li_mtx;
  59 static struct ext4_features *ext4_feat;
  60
  61 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  62                              unsigned long journal_devnum);
  63 static int ext4_commit_super(struct super_block *sb, int sync);
  64 static void ext4_mark_recovery_complete(struct super_block *sb,
  65                                         struct ext4_super_block *es);
  66 static void ext4_clear_journal_err(struct super_block *sb,
  67                                    struct ext4_super_block *es);
  68 static int ext4_sync_fs(struct super_block *sb, int wait);
  69 static const char *ext4_decode_error(struct super_block *sb, int errno,
  70                                      char nbuf[16]);
  71 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  72 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  73 static int ext4_unfreeze(struct super_block *sb);
  74 static void ext4_write_super(struct super_block *sb);
  75 static int ext4_freeze(struct super_block *sb);
  76 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  77                        const char *dev_name, void *data);
  78 static inline int ext2_feature_set_ok(struct super_block *sb);
  79 static inline int ext3_feature_set_ok(struct super_block *sb);
  80 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  81 static void ext4_destroy_lazyinit_thread(void);
  82 static void ext4_unregister_li_request(struct super_block *sb);
  83 static void ext4_clear_request_list(void);
  84
  85 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
  86 static struct file_system_type ext2_fs_type = {
  87         .owner          = THIS_MODULE,
  88         .name           = "ext2",
  89         .mount          = ext4_mount,
  90         .kill_sb        = kill_block_super,
  91         .fs_flags       = FS_REQUIRES_DEV,
  92 };
  93 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
  94 #else
  95 #define IS_EXT2_SB(sb) (0)
  96 #endif
  97
  98
  99 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
 100 static struct file_system_type ext3_fs_type = {
 101         .owner          = THIS_MODULE,
 102         .name           = "ext3",
 103         .mount          = ext4_mount,
 104         .kill_sb        = kill_block_super,
 105         .fs_flags       = FS_REQUIRES_DEV,
 106 };
 107 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 108 #else
 109 #define IS_EXT3_SB(sb) (0)
 110 #endif
 111
 112 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 113                                struct ext4_group_desc *bg)
 114 {
 115         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 116                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 117                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 118 }
 119
 120 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 121                                struct ext4_group_desc *bg)
 122 {
 123         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 124                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 125                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 126 }
 127
 128 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 129                               struct ext4_group_desc *bg)
 130 {
 131         return le32_to_cpu(bg->bg_inode_table_lo) |
 132                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 133                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 134 }
 135
 136 __u32 ext4_free_blks_count(struct super_block *sb,
 137                               struct ext4_group_desc *bg)
 138 {
 139         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 140                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 141                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 142 }
 143
 144 __u32 ext4_free_inodes_count(struct super_block *sb,
 145                               struct ext4_group_desc *bg)
 146 {
 147         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 148                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 149                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 150 }
 151
 152 __u32 ext4_used_dirs_count(struct super_block *sb,
 153                               struct ext4_group_desc *bg)
 154 {
 155         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 156                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 157                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 158 }
 159
 160 __u32 ext4_itable_unused_count(struct super_block *sb,
 161                               struct ext4_group_desc *bg)
 162 {
 163         return le16_to_cpu(bg->bg_itable_unused_lo) |
 164                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 165                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 166 }
 167
 168 void ext4_block_bitmap_set(struct super_block *sb,
 169                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 170 {
 171         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 172         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 173                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 174 }
 175
 176 void ext4_inode_bitmap_set(struct super_block *sb,
 177                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 178 {
 179         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 180         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 181                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 182 }
 183
 184 void ext4_inode_table_set(struct super_block *sb,
 185                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 186 {
 187         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 188         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 189                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 190 }
 191
 192 void ext4_free_blks_set(struct super_block *sb,
 193                           struct ext4_group_desc *bg, __u32 count)
 194 {
 195         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 196         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 197                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 198 }
 199
 200 void ext4_free_inodes_set(struct super_block *sb,
 201                           struct ext4_group_desc *bg, __u32 count)
 202 {
 203         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 204         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 205                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 206 }
 207
 208 void ext4_used_dirs_set(struct super_block *sb,
 209                           struct ext4_group_desc *bg, __u32 count)
 210 {
 211         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 212         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 213                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 214 }
 215
 216 void ext4_itable_unused_set(struct super_block *sb,
 217                           struct ext4_group_desc *bg, __u32 count)
 218 {
 219         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 220         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 221                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 222 }
 223
 224
 225 /* Just increment the non-pointer handle value */
 226 static handle_t *ext4_get_nojournal(void)
 227 {
 228         handle_t *handle = current->journal_info;
 229         unsigned long ref_cnt = (unsigned long)handle;
 230
 231         BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
 232
 233         ref_cnt++;
 234         handle = (handle_t *)ref_cnt;
 235
 236         current->journal_info = handle;
 237         return handle;
 238 }
 239
 240
 241 /* Decrement the non-pointer handle value */
 242 static void ext4_put_nojournal(handle_t *handle)
 243 {
 244         unsigned long ref_cnt = (unsigned long)handle;
 245
 246         BUG_ON(ref_cnt == 0);
 247
 248         ref_cnt--;
 249         handle = (handle_t *)ref_cnt;
 250
 251         current->journal_info = handle;
 252 }
 253
 254 /*
 255  * Wrappers for jbd2_journal_start/end.
 256  *
 257  * The only special thing we need to do here is to make sure that all
 258  * journal_end calls result in the superblock being marked dirty, so
 259  * that sync() will call the filesystem's write_super callback if
 260  * appropriate.
 261  *
 262  * To avoid j_barrier hold in userspace when a user calls freeze(),
 263  * ext4 prevents a new handle from being started by s_frozen, which
 264  * is in an upper layer.
 265  */
 266 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 267 {
 268         journal_t *journal;
 269         handle_t  *handle;
 270
 271         if (sb->s_flags & MS_RDONLY)
 272                 return ERR_PTR(-EROFS);
 273
 274         journal = EXT4_SB(sb)->s_journal;
 275         handle = ext4_journal_current_handle();
 276
 277         /*
 278          * If a handle has been started, it should be allowed to
 279          * finish, otherwise deadlock could happen between freeze
 280          * and others(e.g. truncate) due to the restart of the
 281          * journal handle if the filesystem is forzen and active
 282          * handles are not stopped.
 283          */
 284         if (!handle)
 285                 vfs_check_frozen(sb, SB_FREEZE_TRANS);
 286
 287         if (!journal)
 288                 return ext4_get_nojournal();
 289         /*
 290          * Special case here: if the journal has aborted behind our
 291          * backs (eg. EIO in the commit thread), then we still need to
 292          * take the FS itself readonly cleanly.
 293          */
 294         if (is_journal_aborted(journal)) {
 295                 ext4_abort(sb, "Detected aborted journal");
 296                 return ERR_PTR(-EROFS);
 297         }
 298         return jbd2_journal_start(journal, nblocks);
 299 }
 300
 301 /*
 302  * The only special thing we need to do here is to make sure that all
 303  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 304  * that sync() will call the filesystem's write_super callback if
 305  * appropriate.
 306  */
 307 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)
 308 {
 309         struct super_block *sb;
 310         int err;
 311         int rc;
 312
 313         if (!ext4_handle_valid(handle)) {
 314                 ext4_put_nojournal(handle);
 315                 return 0;
 316         }
 317         sb = handle->h_transaction->t_journal->j_private;
 318         err = handle->h_err;
 319         rc = jbd2_journal_stop(handle);
 320
 321         if (!err)
 322                 err = rc;
 323         if (err)
 324                 __ext4_std_error(sb, where, line, err);
 325         return err;
 326 }
 327
 328 void ext4_journal_abort_handle(const char *caller, unsigned int line,
 329                                const char *err_fn, struct buffer_head *bh,
 330                                handle_t *handle, int err)
 331 {
 332         char nbuf[16];
 333         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 334
 335         BUG_ON(!ext4_handle_valid(handle));
 336
 337         if (bh)
 338                 BUFFER_TRACE(bh, "abort");
 339
 340         if (!handle->h_err)
 341                 handle->h_err = err;
 342
 343         if (is_handle_aborted(handle))
 344                 return;
 345
 346         printk(KERN_ERR "%s:%d: aborting transaction: %s in %s\n",
 347                caller, line, errstr, err_fn);
 348
 349         jbd2_journal_abort_handle(handle);
 350 }
 351
 352 static void __save_error_info(struct super_block *sb, const char *func,
 353                             unsigned int line)
 354 {
 355         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 356
 357         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 358         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 359         es->s_last_error_time = cpu_to_le32(get_seconds());
 360         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 361         es->s_last_error_line = cpu_to_le32(line);
 362         if (!es->s_first_error_time) {
 363                 es->s_first_error_time = es->s_last_error_time;
 364                 strncpy(es->s_first_error_func, func,
 365                         sizeof(es->s_first_error_func));
 366                 es->s_first_error_line = cpu_to_le32(line);
 367                 es->s_first_error_ino = es->s_last_error_ino;
 368                 es->s_first_error_block = es->s_last_error_block;
 369         }
 370         /*
 371          * Start the daily error reporting function if it hasn't been
 372          * started already
 373          */
 374         if (!es->s_error_count)
 375                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 376         es->s_error_count = cpu_to_le32(le32_to_cpu(es->s_error_count) + 1);
 377 }
 378
 379 static void save_error_info(struct super_block *sb, const char *func,
 380                             unsigned int line)
 381 {
 382         __save_error_info(sb, func, line);
 383         ext4_commit_super(sb, 1);
 384 }
 385
 386
 387 /* Deal with the reporting of failure conditions on a filesystem such as
 388  * inconsistencies detected or read IO failures.
 389  *
 390  * On ext2, we can store the error state of the filesystem in the
 391  * superblock.  That is not possible on ext4, because we may have other
 392  * write ordering constraints on the superblock which prevent us from
 393  * writing it out straight away; and given that the journal is about to
 394  * be aborted, we can't rely on the current, or future, transactions to
 395  * write out the superblock safely.
 396  *
 397  * We'll just use the jbd2_journal_abort() error code to record an error in
 398  * the journal instead.  On recovery, the journal will complain about
 399  * that error until we've noted it down and cleared it.
 400  */
 401
 402 static void ext4_handle_error(struct super_block *sb)
 403 {
 404         if (sb->s_flags & MS_RDONLY)
 405                 return;
 406
 407         if (!test_opt(sb, ERRORS_CONT)) {
 408                 journal_t *journal = EXT4_SB(sb)->s_journal;
 409
 410                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 411                 if (journal)
 412                         jbd2_journal_abort(journal, -EIO);
 413         }
 414         if (test_opt(sb, ERRORS_RO)) {
 415                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 416                 sb->s_flags |= MS_RDONLY;
 417         }
 418         if (test_opt(sb, ERRORS_PANIC))
 419                 panic("EXT4-fs (device %s): panic forced after error\n",
 420                         sb->s_id);
 421 }
 422
 423 void __ext4_error(struct super_block *sb, const char *function,
 424                   unsigned int line, const char *fmt, ...)
 425 {
 426         struct va_format vaf;
 427         va_list args;
 428
 429         va_start(args, fmt);
 430         vaf.fmt = fmt;
 431         vaf.va = &args;
 432         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 433                sb->s_id, function, line, current->comm, &vaf);
 434         va_end(args);
 435
 436         ext4_handle_error(sb);
 437 }
 438
 439 void ext4_error_inode(struct inode *inode, const char *function,
 440                       unsigned int line, ext4_fsblk_t block,
 441                       const char *fmt, ...)
 442 {
 443         va_list args;
 444         struct va_format vaf;
 445         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 446
 447         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 448         es->s_last_error_block = cpu_to_le64(block);
 449         save_error_info(inode->i_sb, function, line);
 450         va_start(args, fmt);
 451         vaf.fmt = fmt;
 452         vaf.va = &args;
 453         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: inode #%lu: ",
 454                inode->i_sb->s_id, function, line, inode->i_ino);
 455         if (block)
 456                 printk(KERN_CONT "block %llu: ", block);
 457         printk(KERN_CONT "comm %s: %pV\n", current->comm, &vaf);
 458         va_end(args);
 459
 460         ext4_handle_error(inode->i_sb);
 461 }
 462
 463 void ext4_error_file(struct file *file, const char *function,
 464                      unsigned int line, ext4_fsblk_t block,
 465                      const char *fmt, ...)
 466 {
 467         va_list args;
 468         struct va_format vaf;
 469         struct ext4_super_block *es;
 470         struct inode *inode = file->f_dentry->d_inode;
 471         char pathname[80], *path;
 472
 473         es = EXT4_SB(inode->i_sb)->s_es;
 474         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 475         save_error_info(inode->i_sb, function, line);
 476         path = d_path(&(file->f_path), pathname, sizeof(pathname));
 477         if (IS_ERR(path))
 478                 path = "(unknown)";
 479         printk(KERN_CRIT
 480                "EXT4-fs error (device %s): %s:%d: inode #%lu: ",
 481                inode->i_sb->s_id, function, line, inode->i_ino);
 482         if (block)
 483                 printk(KERN_CONT "block %llu: ", block);
 484         va_start(args, fmt);
 485         vaf.fmt = fmt;
 486         vaf.va = &args;
 487         printk(KERN_CONT "comm %s: path %s: %pV\n", current->comm, path, &vaf);
 488         va_end(args);
 489
 490         ext4_handle_error(inode->i_sb);
 491 }
 492
 493 static const char *ext4_decode_error(struct super_block *sb, int errno,
 494                                      char nbuf[16])
 495 {
 496         char *errstr = NULL;
 497
 498         switch (errno) {
 499         case -EIO:
 500                 errstr = "IO failure";
 501                 break;
 502         case -ENOMEM:
 503                 errstr = "Out of memory";
 504                 break;
 505         case -EROFS:
 506                 if (!sb || (EXT4_SB(sb)->s_journal &&
 507                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 508                         errstr = "Journal has aborted";
 509                 else
 510                         errstr = "Readonly filesystem";
 511                 break;
 512         default:
 513                 /* If the caller passed in an extra buffer for unknown
 514                  * errors, textualise them now.  Else we just return
 515                  * NULL. */
 516                 if (nbuf) {
 517                         /* Check for truncated error codes... */
 518                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 519                                 errstr = nbuf;
 520                 }
 521                 break;
 522         }
 523
 524         return errstr;
 525 }
 526
 527 /* __ext4_std_error decodes expected errors from journaling functions
 528  * automatically and invokes the appropriate error response.  */
 529
 530 void __ext4_std_error(struct super_block *sb, const char *function,
 531                       unsigned int line, int errno)
 532 {
 533         char nbuf[16];
 534         const char *errstr;
 535
 536         /* Special case: if the error is EROFS, and we're not already
 537          * inside a transaction, then there's really no point in logging
 538          * an error. */
 539         if (errno == -EROFS && journal_current_handle() == NULL &&
 540             (sb->s_flags & MS_RDONLY))
 541                 return;
 542
 543         errstr = ext4_decode_error(sb, errno, nbuf);
 544         printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 545                sb->s_id, function, line, errstr);
 546         save_error_info(sb, function, line);
 547
 548         ext4_handle_error(sb);
 549 }
 550
 551 /*
 552  * ext4_abort is a much stronger failure handler than ext4_error.  The
 553  * abort function may be used to deal with unrecoverable failures such
 554  * as journal IO errors or ENOMEM at a critical moment in log management.
 555  *
 556  * We unconditionally force the filesystem into an ABORT|READONLY state,
 557  * unless the error response on the fs has been set to panic in which
 558  * case we take the easy way out and panic immediately.
 559  */
 560
 561 void __ext4_abort(struct super_block *sb, const char *function,
 562                 unsigned int line, const char *fmt, ...)
 563 {
 564         va_list args;
 565
 566         save_error_info(sb, function, line);
 567         va_start(args, fmt);
 568         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
 569                function, line);
 570         vprintk(fmt, args);
 571         printk("\n");
 572         va_end(args);
 573
 574         if ((sb->s_flags & MS_RDONLY) == 0) {
 575                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 576                 sb->s_flags |= MS_RDONLY;
 577                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 578                 if (EXT4_SB(sb)->s_journal)
 579                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 580                 save_error_info(sb, function, line);
 581         }
 582         if (test_opt(sb, ERRORS_PANIC))
 583                 panic("EXT4-fs panic from previous error\n");
 584 }
 585
 586 void ext4_msg(struct super_block *sb, const char *prefix, const char *fmt, ...)
 587 {
 588         struct va_format vaf;
 589         va_list args;
 590
 591         va_start(args, fmt);
 592         vaf.fmt = fmt;
 593         vaf.va = &args;
 594         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 595         va_end(args);
 596 }
 597
 598 void __ext4_warning(struct super_block *sb, const char *function,
 599                     unsigned int line, const char *fmt, ...)
 600 {
 601         struct va_format vaf;
 602         va_list args;
 603
 604         va_start(args, fmt);
 605         vaf.fmt = fmt;
 606         vaf.va = &args;
 607         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 608                sb->s_id, function, line, &vaf);
 609         va_end(args);
 610 }
 611
 612 void __ext4_grp_locked_error(const char *function, unsigned int line,
 613                              struct super_block *sb, ext4_group_t grp,
 614                              unsigned long ino, ext4_fsblk_t block,
 615                              const char *fmt, ...)
 616 __releases(bitlock)
 617 __acquires(bitlock)
 618 {
 619         struct va_format vaf;
 620         va_list args;
 621         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 622
 623         es->s_last_error_ino = cpu_to_le32(ino);
 624         es->s_last_error_block = cpu_to_le64(block);
 625         __save_error_info(sb, function, line);
 626
 627         va_start(args, fmt);
 628
 629         vaf.fmt = fmt;
 630         vaf.va = &args;
 631         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 632                sb->s_id, function, line, grp);
 633         if (ino)
 634                 printk(KERN_CONT "inode %lu: ", ino);
 635         if (block)
 636                 printk(KERN_CONT "block %llu:", (unsigned long long) block);
 637         printk(KERN_CONT "%pV\n", &vaf);
 638         va_end(args);
 639
 640         if (test_opt(sb, ERRORS_CONT)) {
 641                 ext4_commit_super(sb, 0);
 642                 return;
 643         }
 644
 645         ext4_unlock_group(sb, grp);
 646         ext4_handle_error(sb);
 647         /*
 648          * We only get here in the ERRORS_RO case; relocking the group
 649          * may be dangerous, but nothing bad will happen since the
 650          * filesystem will have already been marked read/only and the
 651          * journal has been aborted.  We return 1 as a hint to callers
 652          * who might what to use the return value from
 653          * ext4_grp_locked_error() to distinguish between the
 654          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 655          * aggressively from the ext4 function in question, with a
 656          * more appropriate error code.
 657          */
 658         ext4_lock_group(sb, grp);
 659         return;
 660 }
 661
 662 void ext4_update_dynamic_rev(struct super_block *sb)
 663 {
 664         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 665
 666         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 667                 return;
 668
 669         ext4_warning(sb,
 670                      "updating to rev %d because of new feature flag, "
 671                      "running e2fsck is recommended",
 672                      EXT4_DYNAMIC_REV);
 673
 674         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 675         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 676         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 677         /* leave es->s_feature_*compat flags alone */
 678         /* es->s_uuid will be set by e2fsck if empty */
 679
 680         /*
 681          * The rest of the superblock fields should be zero, and if not it
 682          * means they are likely already in use, so leave them alone.  We
 683          * can leave it up to e2fsck to clean up any inconsistencies there.
 684          */
 685 }
 686
 687 /*
 688  * Open the external journal device
 689  */
 690 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 691 {
 692         struct block_device *bdev;
 693         char b[BDEVNAME_SIZE];
 694
 695         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 696         if (IS_ERR(bdev))
 697                 goto fail;
 698         return bdev;
 699
 700 fail:
 701         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 702                         __bdevname(dev, b), PTR_ERR(bdev));
 703         return NULL;
 704 }
 705
 706 /*
 707  * Release the journal device
 708  */
 709 static int ext4_blkdev_put(struct block_device *bdev)
 710 {
 711         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 712 }
 713
 714 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 715 {
 716         struct block_device *bdev;
 717         int ret = -ENODEV;
 718
 719         bdev = sbi->journal_bdev;
 720         if (bdev) {
 721                 ret = ext4_blkdev_put(bdev);
 722                 sbi->journal_bdev = NULL;
 723         }
 724         return ret;
 725 }
 726
 727 static inline struct inode *orphan_list_entry(struct list_head *l)
 728 {
 729         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 730 }
 731
 732 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 733 {
 734         struct list_head *l;
 735
 736         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 737                  le32_to_cpu(sbi->s_es->s_last_orphan));
 738
 739         printk(KERN_ERR "sb_info orphan list:\n");
 740         list_for_each(l, &sbi->s_orphan) {
 741                 struct inode *inode = orphan_list_entry(l);
 742                 printk(KERN_ERR "  "
 743                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 744                        inode->i_sb->s_id, inode->i_ino, inode,
 745                        inode->i_mode, inode->i_nlink,
 746                        NEXT_ORPHAN(inode));
 747         }
 748 }
 749
 750 static void ext4_put_super(struct super_block *sb)
 751 {
 752         struct ext4_sb_info *sbi = EXT4_SB(sb);
 753         struct ext4_super_block *es = sbi->s_es;
 754         int i, err;
 755
 756         ext4_unregister_li_request(sb);
 757         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 758
 759         flush_workqueue(sbi->dio_unwritten_wq);
 760         destroy_workqueue(sbi->dio_unwritten_wq);
 761
 762         lock_super(sb);
 763         if (sb->s_dirt)
 764                 ext4_commit_super(sb, 1);
 765
 766         if (sbi->s_journal) {
 767                 err = jbd2_journal_destroy(sbi->s_journal);
 768                 sbi->s_journal = NULL;
 769                 if (err < 0)
 770                         ext4_abort(sb, "Couldn't clean up the journal");
 771         }
 772
 773         del_timer(&sbi->s_err_report);
 774         ext4_release_system_zone(sb);
 775         ext4_mb_release(sb);
 776         ext4_ext_release(sb);
 777         ext4_xattr_put_super(sb);
 778
 779         if (!(sb->s_flags & MS_RDONLY)) {
 780                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 781                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 782                 ext4_commit_super(sb, 1);
 783         }
 784         if (sbi->s_proc) {
 785                 remove_proc_entry(sb->s_id, ext4_proc_root);
 786         }
 787         kobject_del(&sbi->s_kobj);
 788
 789         for (i = 0; i < sbi->s_gdb_count; i++)
 790                 brelse(sbi->s_group_desc[i]);
 791         kfree(sbi->s_group_desc);
 792         if (is_vmalloc_addr(sbi->s_flex_groups))
 793                 vfree(sbi->s_flex_groups);
 794         else
 795                 kfree(sbi->s_flex_groups);
 796         percpu_counter_destroy(&sbi->s_freeblocks_counter);
 797         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 798         percpu_counter_destroy(&sbi->s_dirs_counter);
 799         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
 800         brelse(sbi->s_sbh);
 801 #ifdef CONFIG_QUOTA
 802         for (i = 0; i < MAXQUOTAS; i++)
 803                 kfree(sbi->s_qf_names[i]);
 804 #endif
 805
 806         /* Debugging code just in case the in-memory inode orphan list
 807          * isn't empty.  The on-disk one can be non-empty if we've
 808          * detected an error and taken the fs readonly, but the
 809          * in-memory list had better be clean by this point. */
 810         if (!list_empty(&sbi->s_orphan))
 811                 dump_orphan_list(sb, sbi);
 812         J_ASSERT(list_empty(&sbi->s_orphan));
 813
 814         invalidate_bdev(sb->s_bdev);
 815         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 816                 /*
 817                  * Invalidate the journal device's buffers.  We don't want them
 818                  * floating about in memory - the physical journal device may
 819                  * hotswapped, and it breaks the `ro-after' testing code.
 820                  */
 821                 sync_blockdev(sbi->journal_bdev);
 822                 invalidate_bdev(sbi->journal_bdev);
 823                 ext4_blkdev_remove(sbi);
 824         }
 825         sb->s_fs_info = NULL;
 826         /*
 827          * Now that we are completely done shutting down the
 828          * superblock, we need to actually destroy the kobject.
 829          */
 830         unlock_super(sb);
 831         kobject_put(&sbi->s_kobj);
 832         wait_for_completion(&sbi->s_kobj_unregister);
 833         kfree(sbi->s_blockgroup_lock);
 834         kfree(sbi);
 835 }
 836
 837 static struct kmem_cache *ext4_inode_cachep;
 838
 839 /*
 840  * Called inside transaction, so use GFP_NOFS
 841  */
 842 static struct inode *ext4_alloc_inode(struct super_block *sb)
 843 {
 844         struct ext4_inode_info *ei;
 845
 846         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 847         if (!ei)
 848                 return NULL;
 849
 850         ei->vfs_inode.i_version = 1;
 851         ei->vfs_inode.i_data.writeback_index = 0;
 852         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 853         INIT_LIST_HEAD(&ei->i_prealloc_list);
 854         spin_lock_init(&ei->i_prealloc_lock);
 855         ei->i_reserved_data_blocks = 0;
 856         ei->i_reserved_meta_blocks = 0;
 857         ei->i_allocated_meta_blocks = 0;
 858         ei->i_da_metadata_calc_len = 0;
 859         spin_lock_init(&(ei->i_block_reservation_lock));
 860 #ifdef CONFIG_QUOTA
 861         ei->i_reserved_quota = 0;
 862 #endif
 863         ei->jinode = NULL;
 864         INIT_LIST_HEAD(&ei->i_completed_io_list);
 865         spin_lock_init(&ei->i_completed_io_lock);
 866         ei->cur_aio_dio = NULL;
 867         ei->i_sync_tid = 0;
 868         ei->i_datasync_tid = 0;
 869         atomic_set(&ei->i_ioend_count, 0);
 870         atomic_set(&ei->i_aiodio_unwritten, 0);
 871
 872         return &ei->vfs_inode;
 873 }
 874
 875 static int ext4_drop_inode(struct inode *inode)
 876 {
 877         int drop = generic_drop_inode(inode);
 878
 879         trace_ext4_drop_inode(inode, drop);
 880         return drop;
 881 }
 882
 883 static void ext4_i_callback(struct rcu_head *head)
 884 {
 885         struct inode *inode = container_of(head, struct inode, i_rcu);
 886         INIT_LIST_HEAD(&inode->i_dentry);
 887         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 888 }
 889
 890 static void ext4_destroy_inode(struct inode *inode)
 891 {
 892         ext4_ioend_wait(inode);
 893         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 894                 ext4_msg(inode->i_sb, KERN_ERR,
 895                          "Inode %lu (%p): orphan list check failed!",
 896                          inode->i_ino, EXT4_I(inode));
 897                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 898                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 899                                 true);
 900                 dump_stack();
 901         }
 902         call_rcu(&inode->i_rcu, ext4_i_callback);
 903 }
 904
 905 static void init_once(void *foo)
 906 {
 907         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 908
 909         INIT_LIST_HEAD(&ei->i_orphan);
 910 #ifdef CONFIG_EXT4_FS_XATTR
 911         init_rwsem(&ei->xattr_sem);
 912 #endif
 913         init_rwsem(&ei->i_data_sem);
 914         inode_init_once(&ei->vfs_inode);
 915 }
 916
 917 static int init_inodecache(void)
 918 {
 919         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 920                                              sizeof(struct ext4_inode_info),
 921                                              0, (SLAB_RECLAIM_ACCOUNT|
 922                                                 SLAB_MEM_SPREAD),
 923                                              init_once);
 924         if (ext4_inode_cachep == NULL)
 925                 return -ENOMEM;
 926         return 0;
 927 }
 928
 929 static void destroy_inodecache(void)
 930 {
 931         kmem_cache_destroy(ext4_inode_cachep);
 932 }
 933
 934 void ext4_clear_inode(struct inode *inode)
 935 {
 936         invalidate_inode_buffers(inode);
 937         end_writeback(inode);
 938         dquot_drop(inode);
 939         ext4_discard_preallocations(inode);
 940         if (EXT4_I(inode)->jinode) {
 941                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
 942                                                EXT4_I(inode)->jinode);
 943                 jbd2_free_inode(EXT4_I(inode)->jinode);
 944                 EXT4_I(inode)->jinode = NULL;
 945         }
 946 }
 947
 948 static inline void ext4_show_quota_options(struct seq_file *seq,
 949                                            struct super_block *sb)
 950 {
 951 #if defined(CONFIG_QUOTA)
 952         struct ext4_sb_info *sbi = EXT4_SB(sb);
 953
 954         if (sbi->s_jquota_fmt) {
 955                 char *fmtname = "";
 956
 957                 switch (sbi->s_jquota_fmt) {
 958                 case QFMT_VFS_OLD:
 959                         fmtname = "vfsold";
 960                         break;
 961                 case QFMT_VFS_V0:
 962                         fmtname = "vfsv0";
 963                         break;
 964                 case QFMT_VFS_V1:
 965                         fmtname = "vfsv1";
 966                         break;
 967                 }
 968                 seq_printf(seq, ",jqfmt=%s", fmtname);
 969         }
 970
 971         if (sbi->s_qf_names[USRQUOTA])
 972                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
 973
 974         if (sbi->s_qf_names[GRPQUOTA])
 975                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
 976
 977         if (test_opt(sb, USRQUOTA))
 978                 seq_puts(seq, ",usrquota");
 979
 980         if (test_opt(sb, GRPQUOTA))
 981                 seq_puts(seq, ",grpquota");
 982 #endif
 983 }
 984
 985 /*
 986  * Show an option if
 987  *  - it's set to a non-default value OR
 988  *  - if the per-sb default is different from the global default
 989  */
 990 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 991 {
 992         int def_errors;
 993         unsigned long def_mount_opts;
 994         struct super_block *sb = vfs->mnt_sb;
 995         struct ext4_sb_info *sbi = EXT4_SB(sb);
 996         struct ext4_super_block *es = sbi->s_es;
 997
 998         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 999         def_errors     = le16_to_cpu(es->s_errors);
1000
1001         if (sbi->s_sb_block != 1)
1002                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
1003         if (test_opt(sb, MINIX_DF))
1004                 seq_puts(seq, ",minixdf");
1005         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
1006                 seq_puts(seq, ",grpid");
1007         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
1008                 seq_puts(seq, ",nogrpid");
1009         if (sbi->s_resuid != EXT4_DEF_RESUID ||
1010             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
1011                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
1012         }
1013         if (sbi->s_resgid != EXT4_DEF_RESGID ||
1014             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
1015                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
1016         }
1017         if (test_opt(sb, ERRORS_RO)) {
1018                 if (def_errors == EXT4_ERRORS_PANIC ||
1019                     def_errors == EXT4_ERRORS_CONTINUE) {
1020                         seq_puts(seq, ",errors=remount-ro");
1021                 }
1022         }
1023         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1024                 seq_puts(seq, ",errors=continue");
1025         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1026                 seq_puts(seq, ",errors=panic");
1027         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
1028                 seq_puts(seq, ",nouid32");
1029         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
1030                 seq_puts(seq, ",debug");
1031         if (test_opt(sb, OLDALLOC))
1032                 seq_puts(seq, ",oldalloc");
1033 #ifdef CONFIG_EXT4_FS_XATTR
1034         if (test_opt(sb, XATTR_USER))
1035                 seq_puts(seq, ",user_xattr");
1036         if (!test_opt(sb, XATTR_USER))
1037                 seq_puts(seq, ",nouser_xattr");
1038 #endif
1039 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1040         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
1041                 seq_puts(seq, ",acl");
1042         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
1043                 seq_puts(seq, ",noacl");
1044 #endif
1045         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
1046                 seq_printf(seq, ",commit=%u",
1047                            (unsigned) (sbi->s_commit_interval / HZ));
1048         }
1049         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
1050                 seq_printf(seq, ",min_batch_time=%u",
1051                            (unsigned) sbi->s_min_batch_time);
1052         }
1053         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
1054                 seq_printf(seq, ",max_batch_time=%u",
1055                            (unsigned) sbi->s_min_batch_time);
1056         }
1057
1058         /*
1059          * We're changing the default of barrier mount option, so
1060          * let's always display its mount state so it's clear what its
1061          * status is.
1062          */
1063         seq_puts(seq, ",barrier=");
1064         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
1065         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
1066                 seq_puts(seq, ",journal_async_commit");
1067         else if (test_opt(sb, JOURNAL_CHECKSUM))
1068                 seq_puts(seq, ",journal_checksum");
1069         if (test_opt(sb, I_VERSION))
1070                 seq_puts(seq, ",i_version");
1071         if (!test_opt(sb, DELALLOC) &&
1072             !(def_mount_opts & EXT4_DEFM_NODELALLOC))
1073                 seq_puts(seq, ",nodelalloc");
1074
1075         if (!test_opt(sb, MBLK_IO_SUBMIT))
1076                 seq_puts(seq, ",nomblk_io_submit");
1077         if (sbi->s_stripe)
1078                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
1079         /*
1080          * journal mode get enabled in different ways
1081          * So just print the value even if we didn't specify it
1082          */
1083         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1084                 seq_puts(seq, ",data=journal");
1085         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1086                 seq_puts(seq, ",data=ordered");
1087         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1088                 seq_puts(seq, ",data=writeback");
1089
1090         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1091                 seq_printf(seq, ",inode_readahead_blks=%u",
1092                            sbi->s_inode_readahead_blks);
1093
1094         if (test_opt(sb, DATA_ERR_ABORT))
1095                 seq_puts(seq, ",data_err=abort");
1096
1097         if (test_opt(sb, NO_AUTO_DA_ALLOC))
1098                 seq_puts(seq, ",noauto_da_alloc");
1099
1100         if (test_opt(sb, DISCARD) && !(def_mount_opts & EXT4_DEFM_DISCARD))
1101                 seq_puts(seq, ",discard");
1102
1103         if (test_opt(sb, NOLOAD))
1104                 seq_puts(seq, ",norecovery");
1105
1106         if (test_opt(sb, DIOREAD_NOLOCK))
1107                 seq_puts(seq, ",dioread_nolock");
1108
1109         if (test_opt(sb, BLOCK_VALIDITY) &&
1110             !(def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY))
1111                 seq_puts(seq, ",block_validity");
1112
1113         if (!test_opt(sb, INIT_INODE_TABLE))
1114                 seq_puts(seq, ",noinit_inode_table");
1115         else if (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)
1116                 seq_printf(seq, ",init_inode_table=%u",
1117                            (unsigned) sbi->s_li_wait_mult);
1118
1119         ext4_show_quota_options(seq, sb);
1120
1121         return 0;
1122 }
1123
1124 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1125                                         u64 ino, u32 generation)
1126 {
1127         struct inode *inode;
1128
1129         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1130                 return ERR_PTR(-ESTALE);
1131         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1132                 return ERR_PTR(-ESTALE);
1133
1134         /* iget isn't really right if the inode is currently unallocated!!
1135          *
1136          * ext4_read_inode will return a bad_inode if the inode had been
1137          * deleted, so we should be safe.
1138          *
1139          * Currently we don't know the generation for parent directory, so
1140          * a generation of 0 means "accept any"
1141          */
1142         inode = ext4_iget(sb, ino);
1143         if (IS_ERR(inode))
1144                 return ERR_CAST(inode);
1145         if (generation && inode->i_generation != generation) {
1146                 iput(inode);
1147                 return ERR_PTR(-ESTALE);
1148         }
1149
1150         return inode;
1151 }
1152
1153 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1154                                         int fh_len, int fh_type)
1155 {
1156         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1157                                     ext4_nfs_get_inode);
1158 }
1159
1160 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1161                                         int fh_len, int fh_type)
1162 {
1163         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1164                                     ext4_nfs_get_inode);
1165 }
1166
1167 /*
1168  * Try to release metadata pages (indirect blocks, directories) which are
1169  * mapped via the block device.  Since these pages could have journal heads
1170  * which would prevent try_to_free_buffers() from freeing them, we must use
1171  * jbd2 layer's try_to_free_buffers() function to release them.
1172  */
1173 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1174                                  gfp_t wait)
1175 {
1176         journal_t *journal = EXT4_SB(sb)->s_journal;
1177
1178         WARN_ON(PageChecked(page));
1179         if (!page_has_buffers(page))
1180                 return 0;
1181         if (journal)
1182                 return jbd2_journal_try_to_free_buffers(journal, page,
1183                                                         wait & ~__GFP_WAIT);
1184         return try_to_free_buffers(page);
1185 }
1186
1187 #ifdef CONFIG_QUOTA
1188 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1189 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1190
1191 static int ext4_write_dquot(struct dquot *dquot);
1192 static int ext4_acquire_dquot(struct dquot *dquot);
1193 static int ext4_release_dquot(struct dquot *dquot);
1194 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1195 static int ext4_write_info(struct super_block *sb, int type);
1196 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1197                          struct path *path);
1198 static int ext4_quota_off(struct super_block *sb, int type);
1199 static int ext4_quota_on_mount(struct super_block *sb, int type);
1200 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1201                                size_t len, loff_t off);
1202 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1203                                 const char *data, size_t len, loff_t off);
1204
1205 static const struct dquot_operations ext4_quota_operations = {
1206         .get_reserved_space = ext4_get_reserved_space,
1207         .write_dquot    = ext4_write_dquot,
1208         .acquire_dquot  = ext4_acquire_dquot,
1209         .release_dquot  = ext4_release_dquot,
1210         .mark_dirty     = ext4_mark_dquot_dirty,
1211         .write_info     = ext4_write_info,
1212         .alloc_dquot    = dquot_alloc,
1213         .destroy_dquot  = dquot_destroy,
1214 };
1215
1216 static const struct quotactl_ops ext4_qctl_operations = {
1217         .quota_on       = ext4_quota_on,
1218         .quota_off      = ext4_quota_off,
1219         .quota_sync     = dquot_quota_sync,
1220         .get_info       = dquot_get_dqinfo,
1221         .set_info       = dquot_set_dqinfo,
1222         .get_dqblk      = dquot_get_dqblk,
1223         .set_dqblk      = dquot_set_dqblk
1224 };
1225 #endif
1226
1227 static const struct super_operations ext4_sops = {
1228         .alloc_inode    = ext4_alloc_inode,
1229         .destroy_inode  = ext4_destroy_inode,
1230         .write_inode    = ext4_write_inode,
1231         .dirty_inode    = ext4_dirty_inode,
1232         .drop_inode     = ext4_drop_inode,
1233         .evict_inode    = ext4_evict_inode,
1234         .put_super      = ext4_put_super,
1235         .sync_fs        = ext4_sync_fs,
1236         .freeze_fs      = ext4_freeze,
1237         .unfreeze_fs    = ext4_unfreeze,
1238         .statfs         = ext4_statfs,
1239         .remount_fs     = ext4_remount,
1240         .show_options   = ext4_show_options,
1241 #ifdef CONFIG_QUOTA
1242         .quota_read     = ext4_quota_read,
1243         .quota_write    = ext4_quota_write,
1244 #endif
1245         .bdev_try_to_free_page = bdev_try_to_free_page,
1246 };
1247
1248 static const struct super_operations ext4_nojournal_sops = {
1249         .alloc_inode    = ext4_alloc_inode,
1250         .destroy_inode  = ext4_destroy_inode,
1251         .write_inode    = ext4_write_inode,
1252         .dirty_inode    = ext4_dirty_inode,
1253         .drop_inode     = ext4_drop_inode,
1254         .evict_inode    = ext4_evict_inode,
1255         .write_super    = ext4_write_super,
1256         .put_super      = ext4_put_super,
1257         .statfs         = ext4_statfs,
1258         .remount_fs     = ext4_remount,
1259         .show_options   = ext4_show_options,
1260 #ifdef CONFIG_QUOTA
1261         .quota_read     = ext4_quota_read,
1262         .quota_write    = ext4_quota_write,
1263 #endif
1264         .bdev_try_to_free_page = bdev_try_to_free_page,
1265 };
1266
1267 static const struct export_operations ext4_export_ops = {
1268         .fh_to_dentry = ext4_fh_to_dentry,
1269         .fh_to_parent = ext4_fh_to_parent,
1270         .get_parent = ext4_get_parent,
1271 };
1272
1273 enum {
1274         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1275         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1276         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1277         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1278         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1279         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1280         Opt_journal_update, Opt_journal_dev,
1281         Opt_journal_checksum, Opt_journal_async_commit,
1282         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1283         Opt_data_err_abort, Opt_data_err_ignore,
1284         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1285         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1286         Opt_noquota, Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err,
1287         Opt_resize, Opt_usrquota, Opt_grpquota, Opt_i_version,
1288         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1289         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1290         Opt_inode_readahead_blks, Opt_journal_ioprio,
1291         Opt_dioread_nolock, Opt_dioread_lock,
1292         Opt_discard, Opt_nodiscard,
1293         Opt_init_inode_table, Opt_noinit_inode_table,
1294 };
1295
1296 static const match_table_t tokens = {
1297         {Opt_bsd_df, "bsddf"},
1298         {Opt_minix_df, "minixdf"},
1299         {Opt_grpid, "grpid"},
1300         {Opt_grpid, "bsdgroups"},
1301         {Opt_nogrpid, "nogrpid"},
1302         {Opt_nogrpid, "sysvgroups"},
1303         {Opt_resgid, "resgid=%u"},
1304         {Opt_resuid, "resuid=%u"},
1305         {Opt_sb, "sb=%u"},
1306         {Opt_err_cont, "errors=continue"},
1307         {Opt_err_panic, "errors=panic"},
1308         {Opt_err_ro, "errors=remount-ro"},
1309         {Opt_nouid32, "nouid32"},
1310         {Opt_debug, "debug"},
1311         {Opt_oldalloc, "oldalloc"},
1312         {Opt_orlov, "orlov"},
1313         {Opt_user_xattr, "user_xattr"},
1314         {Opt_nouser_xattr, "nouser_xattr"},
1315         {Opt_acl, "acl"},
1316         {Opt_noacl, "noacl"},
1317         {Opt_noload, "noload"},
1318         {Opt_noload, "norecovery"},
1319         {Opt_nobh, "nobh"},
1320         {Opt_bh, "bh"},
1321         {Opt_commit, "commit=%u"},
1322         {Opt_min_batch_time, "min_batch_time=%u"},
1323         {Opt_max_batch_time, "max_batch_time=%u"},
1324         {Opt_journal_update, "journal=update"},
1325         {Opt_journal_dev, "journal_dev=%u"},
1326         {Opt_journal_checksum, "journal_checksum"},
1327         {Opt_journal_async_commit, "journal_async_commit"},
1328         {Opt_abort, "abort"},
1329         {Opt_data_journal, "data=journal"},
1330         {Opt_data_ordered, "data=ordered"},
1331         {Opt_data_writeback, "data=writeback"},
1332         {Opt_data_err_abort, "data_err=abort"},
1333         {Opt_data_err_ignore, "data_err=ignore"},
1334         {Opt_offusrjquota, "usrjquota="},
1335         {Opt_usrjquota, "usrjquota=%s"},
1336         {Opt_offgrpjquota, "grpjquota="},
1337         {Opt_grpjquota, "grpjquota=%s"},
1338         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1339         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1340         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1341         {Opt_grpquota, "grpquota"},
1342         {Opt_noquota, "noquota"},
1343         {Opt_quota, "quota"},
1344         {Opt_usrquota, "usrquota"},
1345         {Opt_barrier, "barrier=%u"},
1346         {Opt_barrier, "barrier"},
1347         {Opt_nobarrier, "nobarrier"},
1348         {Opt_i_version, "i_version"},
1349         {Opt_stripe, "stripe=%u"},
1350         {Opt_resize, "resize"},
1351         {Opt_delalloc, "delalloc"},
1352         {Opt_nodelalloc, "nodelalloc"},
1353         {Opt_mblk_io_submit, "mblk_io_submit"},
1354         {Opt_nomblk_io_submit, "nomblk_io_submit"},
1355         {Opt_block_validity, "block_validity"},
1356         {Opt_noblock_validity, "noblock_validity"},
1357         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1358         {Opt_journal_ioprio, "journal_ioprio=%u"},
1359         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1360         {Opt_auto_da_alloc, "auto_da_alloc"},
1361         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1362         {Opt_dioread_nolock, "dioread_nolock"},
1363         {Opt_dioread_lock, "dioread_lock"},
1364         {Opt_discard, "discard"},
1365         {Opt_nodiscard, "nodiscard"},
1366         {Opt_init_inode_table, "init_itable=%u"},
1367         {Opt_init_inode_table, "init_itable"},
1368         {Opt_noinit_inode_table, "noinit_itable"},
1369         {Opt_err, NULL},
1370 };
1371
1372 static ext4_fsblk_t get_sb_block(void **data)
1373 {
1374         ext4_fsblk_t    sb_block;
1375         char            *options = (char *) *data;
1376
1377         if (!options || strncmp(options, "sb=", 3) != 0)
1378                 return 1;       /* Default location */
1379
1380         options += 3;
1381         /* TODO: use simple_strtoll with >32bit ext4 */
1382         sb_block = simple_strtoul(options, &options, 0);
1383         if (*options && *options != ',') {
1384                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1385                        (char *) *data);
1386                 return 1;
1387         }
1388         if (*options == ',')
1389                 options++;
1390         *data = (void *) options;
1391
1392         return sb_block;
1393 }
1394
1395 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1396 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1397         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1398
1399 #ifdef CONFIG_QUOTA
1400 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1401 {
1402         struct ext4_sb_info *sbi = EXT4_SB(sb);
1403         char *qname;
1404
1405         if (sb_any_quota_loaded(sb) &&
1406                 !sbi->s_qf_names[qtype]) {
1407                 ext4_msg(sb, KERN_ERR,
1408                         "Cannot change journaled "
1409                         "quota options when quota turned on");
1410                 return 0;
1411         }
1412         qname = match_strdup(args);
1413         if (!qname) {
1414                 ext4_msg(sb, KERN_ERR,
1415                         "Not enough memory for storing quotafile name");
1416                 return 0;
1417         }
1418         if (sbi->s_qf_names[qtype] &&
1419                 strcmp(sbi->s_qf_names[qtype], qname)) {
1420                 ext4_msg(sb, KERN_ERR,
1421                         "%s quota file already specified", QTYPE2NAME(qtype));
1422                 kfree(qname);
1423                 return 0;
1424         }
1425         sbi->s_qf_names[qtype] = qname;
1426         if (strchr(sbi->s_qf_names[qtype], '/')) {
1427                 ext4_msg(sb, KERN_ERR,
1428                         "quotafile must be on filesystem root");
1429                 kfree(sbi->s_qf_names[qtype]);
1430                 sbi->s_qf_names[qtype] = NULL;
1431                 return 0;
1432         }
1433         set_opt(sb, QUOTA);
1434         return 1;
1435 }
1436
1437 static int clear_qf_name(struct super_block *sb, int qtype)
1438 {
1439
1440         struct ext4_sb_info *sbi = EXT4_SB(sb);
1441
1442         if (sb_any_quota_loaded(sb) &&
1443                 sbi->s_qf_names[qtype]) {
1444                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1445                         " when quota turned on");
1446                 return 0;
1447         }
1448         /*
1449          * The space will be released later when all options are confirmed
1450          * to be correct
1451          */
1452         sbi->s_qf_names[qtype] = NULL;
1453         return 1;
1454 }
1455 #endif
1456
1457 static int parse_options(char *options, struct super_block *sb,
1458                          unsigned long *journal_devnum,
1459                          unsigned int *journal_ioprio,
1460                          ext4_fsblk_t *n_blocks_count, int is_remount)
1461 {
1462         struct ext4_sb_info *sbi = EXT4_SB(sb);
1463         char *p;
1464         substring_t args[MAX_OPT_ARGS];
1465         int data_opt = 0;
1466         int option;
1467 #ifdef CONFIG_QUOTA
1468         int qfmt;
1469 #endif
1470
1471         if (!options)
1472                 return 1;
1473
1474         while ((p = strsep(&options, ",")) != NULL) {
1475                 int token;
1476                 if (!*p)
1477                         continue;
1478
1479                 /*
1480                  * Initialize args struct so we know whether arg was
1481                  * found; some options take optional arguments.
1482                  */
1483                 args[0].to = args[0].from = NULL;
1484                 token = match_token(p, tokens, args);
1485                 switch (token) {
1486                 case Opt_bsd_df:
1487                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1488                         clear_opt(sb, MINIX_DF);
1489                         break;
1490                 case Opt_minix_df:
1491                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1492                         set_opt(sb, MINIX_DF);
1493
1494                         break;
1495                 case Opt_grpid:
1496                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1497                         set_opt(sb, GRPID);
1498
1499                         break;
1500                 case Opt_nogrpid:
1501                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1502                         clear_opt(sb, GRPID);
1503
1504                         break;
1505                 case Opt_resuid:
1506                         if (match_int(&args[0], &option))
1507                                 return 0;
1508                         sbi->s_resuid = option;
1509                         break;
1510                 case Opt_resgid:
1511                         if (match_int(&args[0], &option))
1512                                 return 0;
1513                         sbi->s_resgid = option;
1514                         break;
1515                 case Opt_sb:
1516                         /* handled by get_sb_block() instead of here */
1517                         /* *sb_block = match_int(&args[0]); */
1518                         break;
1519                 case Opt_err_panic:
1520                         clear_opt(sb, ERRORS_CONT);
1521                         clear_opt(sb, ERRORS_RO);
1522                         set_opt(sb, ERRORS_PANIC);
1523                         break;
1524                 case Opt_err_ro:
1525                         clear_opt(sb, ERRORS_CONT);
1526                         clear_opt(sb, ERRORS_PANIC);
1527                         set_opt(sb, ERRORS_RO);
1528                         break;
1529                 case Opt_err_cont:
1530                         clear_opt(sb, ERRORS_RO);
1531                         clear_opt(sb, ERRORS_PANIC);
1532                         set_opt(sb, ERRORS_CONT);
1533                         break;
1534                 case Opt_nouid32:
1535                         set_opt(sb, NO_UID32);
1536                         break;
1537                 case Opt_debug:
1538                         set_opt(sb, DEBUG);
1539                         break;
1540                 case Opt_oldalloc:
1541                         set_opt(sb, OLDALLOC);
1542                         break;
1543                 case Opt_orlov:
1544                         clear_opt(sb, OLDALLOC);
1545                         break;
1546 #ifdef CONFIG_EXT4_FS_XATTR
1547                 case Opt_user_xattr:
1548                         set_opt(sb, XATTR_USER);
1549                         break;
1550                 case Opt_nouser_xattr:
1551                         clear_opt(sb, XATTR_USER);
1552                         break;
1553 #else
1554                 case Opt_user_xattr:
1555                 case Opt_nouser_xattr:
1556                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1557                         break;
1558 #endif
1559 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1560                 case Opt_acl:
1561                         set_opt(sb, POSIX_ACL);
1562                         break;
1563                 case Opt_noacl:
1564                         clear_opt(sb, POSIX_ACL);
1565                         break;
1566 #else
1567                 case Opt_acl:
1568                 case Opt_noacl:
1569                         ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1570                         break;
1571 #endif
1572                 case Opt_journal_update:
1573                         /* @@@ FIXME */
1574                         /* Eventually we will want to be able to create
1575                            a journal file here.  For now, only allow the
1576                            user to specify an existing inode to be the
1577                            journal file. */
1578                         if (is_remount) {
1579                                 ext4_msg(sb, KERN_ERR,
1580                                          "Cannot specify journal on remount");
1581                                 return 0;
1582                         }
1583                         set_opt(sb, UPDATE_JOURNAL);
1584                         break;
1585                 case Opt_journal_dev:
1586                         if (is_remount) {
1587                                 ext4_msg(sb, KERN_ERR,
1588                                         "Cannot specify journal on remount");
1589                                 return 0;
1590                         }
1591                         if (match_int(&args[0], &option))
1592                                 return 0;
1593                         *journal_devnum = option;
1594                         break;
1595                 case Opt_journal_checksum:
1596                         set_opt(sb, JOURNAL_CHECKSUM);
1597                         break;
1598                 case Opt_journal_async_commit:
1599                         set_opt(sb, JOURNAL_ASYNC_COMMIT);
1600                         set_opt(sb, JOURNAL_CHECKSUM);
1601                         break;
1602                 case Opt_noload:
1603                         set_opt(sb, NOLOAD);
1604                         break;
1605                 case Opt_commit:
1606                         if (match_int(&args[0], &option))
1607                                 return 0;
1608                         if (option < 0)
1609                                 return 0;
1610                         if (option == 0)
1611                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1612                         sbi->s_commit_interval = HZ * option;
1613                         break;
1614                 case Opt_max_batch_time:
1615                         if (match_int(&args[0], &option))
1616                                 return 0;
1617                         if (option < 0)
1618                                 return 0;
1619                         if (option == 0)
1620                                 option = EXT4_DEF_MAX_BATCH_TIME;
1621                         sbi->s_max_batch_time = option;
1622                         break;
1623                 case Opt_min_batch_time:
1624                         if (match_int(&args[0], &option))
1625                                 return 0;
1626                         if (option < 0)
1627                                 return 0;
1628                         sbi->s_min_batch_time = option;
1629                         break;
1630                 case Opt_data_journal:
1631                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1632                         goto datacheck;
1633                 case Opt_data_ordered:
1634                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1635                         goto datacheck;
1636                 case Opt_data_writeback:
1637                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1638                 datacheck:
1639                         if (is_remount) {
1640                                 if (test_opt(sb, DATA_FLAGS) != data_opt) {
1641                                         ext4_msg(sb, KERN_ERR,
1642                                                 "Cannot change data mode on remount");
1643                                         return 0;
1644                                 }
1645                         } else {
1646                                 clear_opt(sb, DATA_FLAGS);
1647                                 sbi->s_mount_opt |= data_opt;
1648                         }
1649                         break;
1650                 case Opt_data_err_abort:
1651                         set_opt(sb, DATA_ERR_ABORT);
1652                         break;
1653                 case Opt_data_err_ignore:
1654                         clear_opt(sb, DATA_ERR_ABORT);
1655                         break;
1656 #ifdef CONFIG_QUOTA
1657                 case Opt_usrjquota:
1658                         if (!set_qf_name(sb, USRQUOTA, &args[0]))
1659                                 return 0;
1660                         break;
1661                 case Opt_grpjquota:
1662                         if (!set_qf_name(sb, GRPQUOTA, &args[0]))
1663                                 return 0;
1664                         break;
1665                 case Opt_offusrjquota:
1666                         if (!clear_qf_name(sb, USRQUOTA))
1667                                 return 0;
1668                         break;
1669                 case Opt_offgrpjquota:
1670                         if (!clear_qf_name(sb, GRPQUOTA))
1671                                 return 0;
1672                         break;
1673
1674                 case Opt_jqfmt_vfsold:
1675                         qfmt = QFMT_VFS_OLD;
1676                         goto set_qf_format;
1677                 case Opt_jqfmt_vfsv0:
1678                         qfmt = QFMT_VFS_V0;
1679                         goto set_qf_format;
1680                 case Opt_jqfmt_vfsv1:
1681                         qfmt = QFMT_VFS_V1;
1682 set_qf_format:
1683                         if (sb_any_quota_loaded(sb) &&
1684                             sbi->s_jquota_fmt != qfmt) {
1685                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1686                                         "journaled quota options when "
1687                                         "quota turned on");
1688                                 return 0;
1689                         }
1690                         sbi->s_jquota_fmt = qfmt;
1691                         break;
1692                 case Opt_quota:
1693                 case Opt_usrquota:
1694                         set_opt(sb, QUOTA);
1695                         set_opt(sb, USRQUOTA);
1696                         break;
1697                 case Opt_grpquota:
1698                         set_opt(sb, QUOTA);
1699                         set_opt(sb, GRPQUOTA);
1700                         break;
1701                 case Opt_noquota:
1702                         if (sb_any_quota_loaded(sb)) {
1703                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1704                                         "options when quota turned on");
1705                                 return 0;
1706                         }
1707                         clear_opt(sb, QUOTA);
1708                         clear_opt(sb, USRQUOTA);
1709                         clear_opt(sb, GRPQUOTA);
1710                         break;
1711 #else
1712                 case Opt_quota:
1713                 case Opt_usrquota:
1714                 case Opt_grpquota:
1715                         ext4_msg(sb, KERN_ERR,
1716                                 "quota options not supported");
1717                         break;
1718                 case Opt_usrjquota:
1719                 case Opt_grpjquota:
1720                 case Opt_offusrjquota:
1721                 case Opt_offgrpjquota:
1722                 case Opt_jqfmt_vfsold:
1723                 case Opt_jqfmt_vfsv0:
1724                 case Opt_jqfmt_vfsv1:
1725                         ext4_msg(sb, KERN_ERR,
1726                                 "journaled quota options not supported");
1727                         break;
1728                 case Opt_noquota:
1729                         break;
1730 #endif
1731                 case Opt_abort:
1732                         sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1733                         break;
1734                 case Opt_nobarrier:
1735                         clear_opt(sb, BARRIER);
1736                         break;
1737                 case Opt_barrier:
1738                         if (args[0].from) {
1739                                 if (match_int(&args[0], &option))
1740                                         return 0;
1741                         } else
1742                                 option = 1;     /* No argument, default to 1 */
1743                         if (option)
1744                                 set_opt(sb, BARRIER);
1745                         else
1746                                 clear_opt(sb, BARRIER);
1747                         break;
1748                 case Opt_ignore:
1749                         break;
1750                 case Opt_resize:
1751                         if (!is_remount) {
1752                                 ext4_msg(sb, KERN_ERR,
1753                                         "resize option only available "
1754                                         "for remount");
1755                                 return 0;
1756                         }
1757                         if (match_int(&args[0], &option) != 0)
1758                                 return 0;
1759                         *n_blocks_count = option;
1760                         break;
1761                 case Opt_nobh:
1762                         ext4_msg(sb, KERN_WARNING,
1763                                  "Ignoring deprecated nobh option");
1764                         break;
1765                 case Opt_bh:
1766                         ext4_msg(sb, KERN_WARNING,
1767                                  "Ignoring deprecated bh option");
1768                         break;
1769                 case Opt_i_version:
1770                         set_opt(sb, I_VERSION);
1771                         sb->s_flags |= MS_I_VERSION;
1772                         break;
1773                 case Opt_nodelalloc:
1774                         clear_opt(sb, DELALLOC);
1775                         break;
1776                 case Opt_mblk_io_submit:
1777                         set_opt(sb, MBLK_IO_SUBMIT);
1778                         break;
1779                 case Opt_nomblk_io_submit:
1780                         clear_opt(sb, MBLK_IO_SUBMIT);
1781                         break;
1782                 case Opt_stripe:
1783                         if (match_int(&args[0], &option))
1784                                 return 0;
1785                         if (option < 0)
1786                                 return 0;
1787                         sbi->s_stripe = option;
1788                         break;
1789                 case Opt_delalloc:
1790                         set_opt(sb, DELALLOC);
1791                         break;
1792                 case Opt_block_validity:
1793                         set_opt(sb, BLOCK_VALIDITY);
1794                         break;
1795                 case Opt_noblock_validity:
1796                         clear_opt(sb, BLOCK_VALIDITY);
1797                         break;
1798                 case Opt_inode_readahead_blks:
1799                         if (match_int(&args[0], &option))
1800                                 return 0;
1801                         if (option < 0 || option > (1 << 30))
1802                                 return 0;
1803                         if (option && !is_power_of_2(option)) {
1804                                 ext4_msg(sb, KERN_ERR,
1805                                          "EXT4-fs: inode_readahead_blks"
1806                                          " must be a power of 2");
1807                                 return 0;
1808                         }
1809                         sbi->s_inode_readahead_blks = option;
1810                         break;
1811                 case Opt_journal_ioprio:
1812                         if (match_int(&args[0], &option))
1813                                 return 0;
1814                         if (option < 0 || option > 7)
1815                                 break;
1816                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1817                                                             option);
1818                         break;
1819                 case Opt_noauto_da_alloc:
1820                         set_opt(sb, NO_AUTO_DA_ALLOC);
1821                         break;
1822                 case Opt_auto_da_alloc:
1823                         if (args[0].from) {
1824                                 if (match_int(&args[0], &option))
1825                                         return 0;
1826                         } else
1827                                 option = 1;     /* No argument, default to 1 */
1828                         if (option)
1829                                 clear_opt(sb, NO_AUTO_DA_ALLOC);
1830                         else
1831                                 set_opt(sb,NO_AUTO_DA_ALLOC);
1832                         break;
1833                 case Opt_discard:
1834                         set_opt(sb, DISCARD);
1835                         break;
1836                 case Opt_nodiscard:
1837                         clear_opt(sb, DISCARD);
1838                         break;
1839                 case Opt_dioread_nolock:
1840                         set_opt(sb, DIOREAD_NOLOCK);
1841                         break;
1842                 case Opt_dioread_lock:
1843                         clear_opt(sb, DIOREAD_NOLOCK);
1844                         break;
1845                 case Opt_init_inode_table:
1846                         set_opt(sb, INIT_INODE_TABLE);
1847                         if (args[0].from) {
1848                                 if (match_int(&args[0], &option))
1849                                         return 0;
1850                         } else
1851                                 option = EXT4_DEF_LI_WAIT_MULT;
1852                         if (option < 0)
1853                                 return 0;
1854                         sbi->s_li_wait_mult = option;
1855                         break;
1856                 case Opt_noinit_inode_table:
1857                         clear_opt(sb, INIT_INODE_TABLE);
1858                         break;
1859                 default:
1860                         ext4_msg(sb, KERN_ERR,
1861                                "Unrecognized mount option \"%s\" "
1862                                "or missing value", p);
1863                         return 0;
1864                 }
1865         }
1866 #ifdef CONFIG_QUOTA
1867         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1868                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1869                         clear_opt(sb, USRQUOTA);
1870
1871                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1872                         clear_opt(sb, GRPQUOTA);
1873
1874                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1875                         ext4_msg(sb, KERN_ERR, "old and new quota "
1876                                         "format mixing");
1877                         return 0;
1878                 }
1879
1880                 if (!sbi->s_jquota_fmt) {
1881                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1882                                         "not specified");
1883                         return 0;
1884                 }
1885         } else {
1886                 if (sbi->s_jquota_fmt) {
1887                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1888                                         "specified with no journaling "
1889                                         "enabled");
1890                         return 0;
1891                 }
1892         }
1893 #endif
1894         return 1;
1895 }
1896
1897 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1898                             int read_only)
1899 {
1900         struct ext4_sb_info *sbi = EXT4_SB(sb);
1901         int res = 0;
1902
1903         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1904                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1905                          "forcing read-only mode");
1906                 res = MS_RDONLY;
1907         }
1908         if (read_only)
1909                 return res;
1910         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1911                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1912                          "running e2fsck is recommended");
1913         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1914                 ext4_msg(sb, KERN_WARNING,
1915                          "warning: mounting fs with errors, "
1916                          "running e2fsck is recommended");
1917         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1918                  le16_to_cpu(es->s_mnt_count) >=
1919                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1920                 ext4_msg(sb, KERN_WARNING,
1921                          "warning: maximal mount count reached, "
1922                          "running e2fsck is recommended");
1923         else if (le32_to_cpu(es->s_checkinterval) &&
1924                 (le32_to_cpu(es->s_lastcheck) +
1925                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1926                 ext4_msg(sb, KERN_WARNING,
1927                          "warning: checktime reached, "
1928                          "running e2fsck is recommended");
1929         if (!sbi->s_journal)
1930                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1931         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1932                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1933         le16_add_cpu(&es->s_mnt_count, 1);
1934         es->s_mtime = cpu_to_le32(get_seconds());
1935         ext4_update_dynamic_rev(sb);
1936         if (sbi->s_journal)
1937                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1938
1939         ext4_commit_super(sb, 1);
1940         if (test_opt(sb, DEBUG))
1941                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1942                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1943                         sb->s_blocksize,
1944                         sbi->s_groups_count,
1945                         EXT4_BLOCKS_PER_GROUP(sb),
1946                         EXT4_INODES_PER_GROUP(sb),
1947                         sbi->s_mount_opt, sbi->s_mount_opt2);
1948
1949         return res;
1950 }
1951
1952 static int ext4_fill_flex_info(struct super_block *sb)
1953 {
1954         struct ext4_sb_info *sbi = EXT4_SB(sb);
1955         struct ext4_group_desc *gdp = NULL;
1956         ext4_group_t flex_group_count;
1957         ext4_group_t flex_group;
1958         int groups_per_flex = 0;
1959         size_t size;
1960         int i;
1961
1962         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1963         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1964
1965         if (groups_per_flex < 2) {
1966                 sbi->s_log_groups_per_flex = 0;
1967                 return 1;
1968         }
1969
1970         /* We allocate both existing and potentially added groups */
1971         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1972                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1973                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1974         size = flex_group_count * sizeof(struct flex_groups);
1975         sbi->s_flex_groups = kzalloc(size, GFP_KERNEL);
1976         if (sbi->s_flex_groups == NULL) {
1977                 sbi->s_flex_groups = vzalloc(size);
1978                 if (sbi->s_flex_groups == NULL) {
1979                         ext4_msg(sb, KERN_ERR,
1980                                  "not enough memory for %u flex groups",
1981                                  flex_group_count);
1982                         goto failed;
1983                 }
1984         }
1985
1986         for (i = 0; i < sbi->s_groups_count; i++) {
1987                 gdp = ext4_get_group_desc(sb, i, NULL);
1988
1989                 flex_group = ext4_flex_group(sbi, i);
1990                 atomic_add(ext4_free_inodes_count(sb, gdp),
1991                            &sbi->s_flex_groups[flex_group].free_inodes);
1992                 atomic_add(ext4_free_blks_count(sb, gdp),
1993                            &sbi->s_flex_groups[flex_group].free_blocks);
1994                 atomic_add(ext4_used_dirs_count(sb, gdp),
1995                            &sbi->s_flex_groups[flex_group].used_dirs);
1996         }
1997
1998         return 1;
1999 failed:
2000         return 0;
2001 }
2002
2003 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
2004                             struct ext4_group_desc *gdp)
2005 {
2006         __u16 crc = 0;
2007
2008         if (sbi->s_es->s_feature_ro_compat &
2009             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
2010                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
2011                 __le32 le_group = cpu_to_le32(block_group);
2012
2013                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2014                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2015                 crc = crc16(crc, (__u8 *)gdp, offset);
2016                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
2017                 /* for checksum of struct ext4_group_desc do the rest...*/
2018                 if ((sbi->s_es->s_feature_incompat &
2019                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
2020                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
2021                         crc = crc16(crc, (__u8 *)gdp + offset,
2022                                     le16_to_cpu(sbi->s_es->s_desc_size) -
2023                                         offset);
2024         }
2025
2026         return cpu_to_le16(crc);
2027 }
2028
2029 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
2030                                 struct ext4_group_desc *gdp)
2031 {
2032         if ((sbi->s_es->s_feature_ro_compat &
2033              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
2034             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
2035                 return 0;
2036
2037         return 1;
2038 }
2039
2040 /* Called at mount-time, super-block is locked */
2041 static int ext4_check_descriptors(struct super_block *sb,
2042                                   ext4_group_t *first_not_zeroed)
2043 {
2044         struct ext4_sb_info *sbi = EXT4_SB(sb);
2045         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2046         ext4_fsblk_t last_block;
2047         ext4_fsblk_t block_bitmap;
2048         ext4_fsblk_t inode_bitmap;
2049         ext4_fsblk_t inode_table;
2050         int flexbg_flag = 0;
2051         ext4_group_t i, grp = sbi->s_groups_count;
2052
2053         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2054                 flexbg_flag = 1;
2055
2056         ext4_debug("Checking group descriptors");
2057
2058         for (i = 0; i < sbi->s_groups_count; i++) {
2059                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2060
2061                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2062                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2063                 else
2064                         last_block = first_block +
2065                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2066
2067                 if ((grp == sbi->s_groups_count) &&
2068                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2069                         grp = i;
2070
2071                 block_bitmap = ext4_block_bitmap(sb, gdp);
2072                 if (block_bitmap < first_block || block_bitmap > last_block) {
2073                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2074                                "Block bitmap for group %u not in group "
2075                                "(block %llu)!", i, block_bitmap);
2076                         return 0;
2077                 }
2078                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2079                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2080                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2081                                "Inode bitmap for group %u not in group "
2082                                "(block %llu)!", i, inode_bitmap);
2083                         return 0;
2084                 }
2085                 inode_table = ext4_inode_table(sb, gdp);
2086                 if (inode_table < first_block ||
2087                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2088                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2089                                "Inode table for group %u not in group "
2090                                "(block %llu)!", i, inode_table);
2091                         return 0;
2092                 }
2093                 ext4_lock_group(sb, i);
2094                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
2095                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2096                                  "Checksum for group %u failed (%u!=%u)",
2097                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2098                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2099                         if (!(sb->s_flags & MS_RDONLY)) {
2100                                 ext4_unlock_group(sb, i);
2101                                 return 0;
2102                         }
2103                 }
2104                 ext4_unlock_group(sb, i);
2105                 if (!flexbg_flag)
2106                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2107         }
2108         if (NULL != first_not_zeroed)
2109                 *first_not_zeroed = grp;
2110
2111         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
2112         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
2113         return 1;
2114 }
2115
2116 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2117  * the superblock) which were deleted from all directories, but held open by
2118  * a process at the time of a crash.  We walk the list and try to delete these
2119  * inodes at recovery time (only with a read-write filesystem).
2120  *
2121  * In order to keep the orphan inode chain consistent during traversal (in
2122  * case of crash during recovery), we link each inode into the superblock
2123  * orphan list_head and handle it the same way as an inode deletion during
2124  * normal operation (which journals the operations for us).
2125  *
2126  * We only do an iget() and an iput() on each inode, which is very safe if we
2127  * accidentally point at an in-use or already deleted inode.  The worst that
2128  * can happen in this case is that we get a "bit already cleared" message from
2129  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2130  * e2fsck was run on this filesystem, and it must have already done the orphan
2131  * inode cleanup for us, so we can safely abort without any further action.
2132  */
2133 static void ext4_orphan_cleanup(struct super_block *sb,
2134                                 struct ext4_super_block *es)
2135 {
2136         unsigned int s_flags = sb->s_flags;
2137         int nr_orphans = 0, nr_truncates = 0;
2138 #ifdef CONFIG_QUOTA
2139         int i;
2140 #endif
2141         if (!es->s_last_orphan) {
2142                 jbd_debug(4, "no orphan inodes to clean up\n");
2143                 return;
2144         }
2145
2146         if (bdev_read_only(sb->s_bdev)) {
2147                 ext4_msg(sb, KERN_ERR, "write access "
2148                         "unavailable, skipping orphan cleanup");
2149                 return;
2150         }
2151
2152         /* Check if feature set would not allow a r/w mount */
2153         if (!ext4_feature_set_ok(sb, 0)) {
2154                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2155                          "unknown ROCOMPAT features");
2156                 return;
2157         }
2158
2159         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2160                 if (es->s_last_orphan)
2161                         jbd_debug(1, "Errors on filesystem, "
2162                                   "clearing orphan list.\n");
2163                 es->s_last_orphan = 0;
2164                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2165                 return;
2166         }
2167
2168         if (s_flags & MS_RDONLY) {
2169                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2170                 sb->s_flags &= ~MS_RDONLY;
2171         }
2172 #ifdef CONFIG_QUOTA
2173         /* Needed for iput() to work correctly and not trash data */
2174         sb->s_flags |= MS_ACTIVE;
2175         /* Turn on quotas so that they are updated correctly */
2176         for (i = 0; i < MAXQUOTAS; i++) {
2177                 if (EXT4_SB(sb)->s_qf_names[i]) {
2178                         int ret = ext4_quota_on_mount(sb, i);
2179                         if (ret < 0)
2180                                 ext4_msg(sb, KERN_ERR,
2181                                         "Cannot turn on journaled "
2182                                         "quota: error %d", ret);
2183                 }
2184         }
2185 #endif
2186
2187         while (es->s_last_orphan) {
2188                 struct inode *inode;
2189
2190                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2191                 if (IS_ERR(inode)) {
2192                         es->s_last_orphan = 0;
2193                         break;
2194                 }
2195
2196                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2197                 dquot_initialize(inode);
2198                 if (inode->i_nlink) {
2199                         ext4_msg(sb, KERN_DEBUG,
2200                                 "%s: truncating inode %lu to %lld bytes",
2201                                 __func__, inode->i_ino, inode->i_size);
2202                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2203                                   inode->i_ino, inode->i_size);
2204                         ext4_truncate(inode);
2205                         nr_truncates++;
2206                 } else {
2207                         ext4_msg(sb, KERN_DEBUG,
2208                                 "%s: deleting unreferenced inode %lu",
2209                                 __func__, inode->i_ino);
2210                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2211                                   inode->i_ino);
2212                         nr_orphans++;
2213                 }
2214                 iput(inode);  /* The delete magic happens here! */
2215         }
2216
2217 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2218
2219         if (nr_orphans)
2220                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2221                        PLURAL(nr_orphans));
2222         if (nr_truncates)
2223                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2224                        PLURAL(nr_truncates));
2225 #ifdef CONFIG_QUOTA
2226         /* Turn quotas off */
2227         for (i = 0; i < MAXQUOTAS; i++) {
2228                 if (sb_dqopt(sb)->files[i])
2229                         dquot_quota_off(sb, i);
2230         }
2231 #endif
2232         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2233 }
2234
2235 /*
2236  * Maximal extent format file size.
2237  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2238  * extent format containers, within a sector_t, and within i_blocks
2239  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2240  * so that won't be a limiting factor.
2241  *
2242  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2243  */
2244 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2245 {
2246         loff_t res;
2247         loff_t upper_limit = MAX_LFS_FILESIZE;
2248
2249         /* small i_blocks in vfs inode? */
2250         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2251                 /*
2252                  * CONFIG_LBDAF is not enabled implies the inode
2253                  * i_block represent total blocks in 512 bytes
2254                  * 32 == size of vfs inode i_blocks * 8
2255                  */
2256                 upper_limit = (1LL << 32) - 1;
2257
2258                 /* total blocks in file system block size */
2259                 upper_limit >>= (blkbits - 9);
2260                 upper_limit <<= blkbits;
2261         }
2262
2263         /* 32-bit extent-start container, ee_block */
2264         res = 1LL << 32;
2265         res <<= blkbits;
2266         res -= 1;
2267
2268         /* Sanity check against vm- & vfs- imposed limits */
2269         if (res > upper_limit)
2270                 res = upper_limit;
2271
2272         return res;
2273 }
2274
2275 /*
2276  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2277  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2278  * We need to be 1 filesystem block less than the 2^48 sector limit.
2279  */
2280 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2281 {
2282         loff_t res = EXT4_NDIR_BLOCKS;
2283         int meta_blocks;
2284         loff_t upper_limit;
2285         /* This is calculated to be the largest file size for a dense, block
2286          * mapped file such that the file's total number of 512-byte sectors,
2287          * including data and all indirect blocks, does not exceed (2^48 - 1).
2288          *
2289          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2290          * number of 512-byte sectors of the file.
2291          */
2292
2293         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2294                 /*
2295                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2296                  * the inode i_block field represents total file blocks in
2297                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2298                  */
2299                 upper_limit = (1LL << 32) - 1;
2300
2301                 /* total blocks in file system block size */
2302                 upper_limit >>= (bits - 9);
2303
2304         } else {
2305                 /*
2306                  * We use 48 bit ext4_inode i_blocks
2307                  * With EXT4_HUGE_FILE_FL set the i_blocks
2308                  * represent total number of blocks in
2309                  * file system block size
2310                  */
2311                 upper_limit = (1LL << 48) - 1;
2312
2313         }
2314
2315         /* indirect blocks */
2316         meta_blocks = 1;
2317         /* double indirect blocks */
2318         meta_blocks += 1 + (1LL << (bits-2));
2319         /* tripple indirect blocks */
2320         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2321
2322         upper_limit -= meta_blocks;
2323         upper_limit <<= bits;
2324
2325         res += 1LL << (bits-2);
2326         res += 1LL << (2*(bits-2));
2327         res += 1LL << (3*(bits-2));
2328         res <<= bits;
2329         if (res > upper_limit)
2330                 res = upper_limit;
2331
2332         if (res > MAX_LFS_FILESIZE)
2333                 res = MAX_LFS_FILESIZE;
2334
2335         return res;
2336 }
2337
2338 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2339                                    ext4_fsblk_t logical_sb_block, int nr)
2340 {
2341         struct ext4_sb_info *sbi = EXT4_SB(sb);
2342         ext4_group_t bg, first_meta_bg;
2343         int has_super = 0;
2344
2345         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2346
2347         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2348             nr < first_meta_bg)
2349                 return logical_sb_block + nr + 1;
2350         bg = sbi->s_desc_per_block * nr;
2351         if (ext4_bg_has_super(sb, bg))
2352                 has_super = 1;
2353
2354         return (has_super + ext4_group_first_block_no(sb, bg));
2355 }
2356
2357 /**
2358  * ext4_get_stripe_size: Get the stripe size.
2359  * @sbi: In memory super block info
2360  *
2361  * If we have specified it via mount option, then
2362  * use the mount option value. If the value specified at mount time is
2363  * greater than the blocks per group use the super block value.
2364  * If the super block value is greater than blocks per group return 0.
2365  * Allocator needs it be less than blocks per group.
2366  *
2367  */
2368 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2369 {
2370         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2371         unsigned long stripe_width =
2372                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2373
2374         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2375                 return sbi->s_stripe;
2376
2377         if (stripe_width <= sbi->s_blocks_per_group)
2378                 return stripe_width;
2379
2380         if (stride <= sbi->s_blocks_per_group)
2381                 return stride;
2382
2383         return 0;
2384 }
2385
2386 /* sysfs supprt */
2387
2388 struct ext4_attr {
2389         struct attribute attr;
2390         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2391         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2392                          const char *, size_t);
2393         int offset;
2394 };
2395
2396 static int parse_strtoul(const char *buf,
2397                 unsigned long max, unsigned long *value)
2398 {
2399         char *endp;
2400
2401         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2402         endp = skip_spaces(endp);
2403         if (*endp || *value > max)
2404                 return -EINVAL;
2405
2406         return 0;
2407 }
2408
2409 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2410                                               struct ext4_sb_info *sbi,
2411                                               char *buf)
2412 {
2413         return snprintf(buf, PAGE_SIZE, "%llu\n",
2414                         (s64) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
2415 }
2416
2417 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2418                                          struct ext4_sb_info *sbi, char *buf)
2419 {
2420         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2421
2422         if (!sb->s_bdev->bd_part)
2423                 return snprintf(buf, PAGE_SIZE, "0\n");
2424         return snprintf(buf, PAGE_SIZE, "%lu\n",
2425                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2426                          sbi->s_sectors_written_start) >> 1);
2427 }
2428
2429 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2430                                           struct ext4_sb_info *sbi, char *buf)
2431 {
2432         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2433
2434         if (!sb->s_bdev->bd_part)
2435                 return snprintf(buf, PAGE_SIZE, "0\n");
2436         return snprintf(buf, PAGE_SIZE, "%llu\n",
2437                         (unsigned long long)(sbi->s_kbytes_written +
2438                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2439                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2440 }
2441
2442 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2443                                           struct ext4_sb_info *sbi,
2444                                           const char *buf, size_t count)
2445 {
2446         unsigned long t;
2447
2448         if (parse_strtoul(buf, 0x40000000, &t))
2449                 return -EINVAL;
2450
2451         if (t && !is_power_of_2(t))
2452                 return -EINVAL;
2453
2454         sbi->s_inode_readahead_blks = t;
2455         return count;
2456 }
2457
2458 static ssize_t sbi_ui_show(struct ext4_attr *a,
2459                            struct ext4_sb_info *sbi, char *buf)
2460 {
2461         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2462
2463         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2464 }
2465
2466 static ssize_t sbi_ui_store(struct ext4_attr *a,
2467                             struct ext4_sb_info *sbi,
2468                             const char *buf, size_t count)
2469 {
2470         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2471         unsigned long t;
2472
2473         if (parse_strtoul(buf, 0xffffffff, &t))
2474                 return -EINVAL;
2475         *ui = t;
2476         return count;
2477 }
2478
2479 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2480 static struct ext4_attr ext4_attr_##_name = {                   \
2481         .attr = {.name = __stringify(_name), .mode = _mode },   \
2482         .show   = _show,                                        \
2483         .store  = _store,                                       \
2484         .offset = offsetof(struct ext4_sb_info, _elname),       \
2485 }
2486 #define EXT4_ATTR(name, mode, show, store) \
2487 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2488
2489 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2490 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2491 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2492 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2493         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2494 #define ATTR_LIST(name) &ext4_attr_##name.attr
2495
2496 EXT4_RO_ATTR(delayed_allocation_blocks);
2497 EXT4_RO_ATTR(session_write_kbytes);
2498 EXT4_RO_ATTR(lifetime_write_kbytes);
2499 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2500                  inode_readahead_blks_store, s_inode_readahead_blks);
2501 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2502 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2503 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2504 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2505 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2506 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2507 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2508 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2509
2510 static struct attribute *ext4_attrs[] = {
2511         ATTR_LIST(delayed_allocation_blocks),
2512         ATTR_LIST(session_write_kbytes),
2513         ATTR_LIST(lifetime_write_kbytes),
2514         ATTR_LIST(inode_readahead_blks),
2515         ATTR_LIST(inode_goal),
2516         ATTR_LIST(mb_stats),
2517         ATTR_LIST(mb_max_to_scan),
2518         ATTR_LIST(mb_min_to_scan),
2519         ATTR_LIST(mb_order2_req),
2520         ATTR_LIST(mb_stream_req),
2521         ATTR_LIST(mb_group_prealloc),
2522         ATTR_LIST(max_writeback_mb_bump),
2523         NULL,
2524 };
2525
2526 /* Features this copy of ext4 supports */
2527 EXT4_INFO_ATTR(lazy_itable_init);
2528 EXT4_INFO_ATTR(batched_discard);
2529
2530 static struct attribute *ext4_feat_attrs[] = {
2531         ATTR_LIST(lazy_itable_init),
2532         ATTR_LIST(batched_discard),
2533         NULL,
2534 };
2535
2536 static ssize_t ext4_attr_show(struct kobject *kobj,
2537                               struct attribute *attr, char *buf)
2538 {
2539         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2540                                                 s_kobj);
2541         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2542
2543         return a->show ? a->show(a, sbi, buf) : 0;
2544 }
2545
2546 static ssize_t ext4_attr_store(struct kobject *kobj,
2547                                struct attribute *attr,
2548                                const char *buf, size_t len)
2549 {
2550         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2551                                                 s_kobj);
2552         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2553
2554         return a->store ? a->store(a, sbi, buf, len) : 0;
2555 }
2556
2557 static void ext4_sb_release(struct kobject *kobj)
2558 {
2559         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2560                                                 s_kobj);
2561         complete(&sbi->s_kobj_unregister);
2562 }
2563
2564 static const struct sysfs_ops ext4_attr_ops = {
2565         .show   = ext4_attr_show,
2566         .store  = ext4_attr_store,
2567 };
2568
2569 static struct kobj_type ext4_ktype = {
2570         .default_attrs  = ext4_attrs,
2571         .sysfs_ops      = &ext4_attr_ops,
2572         .release        = ext4_sb_release,
2573 };
2574
2575 static void ext4_feat_release(struct kobject *kobj)
2576 {
2577         complete(&ext4_feat->f_kobj_unregister);
2578 }
2579
2580 static struct kobj_type ext4_feat_ktype = {
2581         .default_attrs  = ext4_feat_attrs,
2582         .sysfs_ops      = &ext4_attr_ops,
2583         .release        = ext4_feat_release,
2584 };
2585
2586 /*
2587  * Check whether this filesystem can be mounted based on
2588  * the features present and the RDONLY/RDWR mount requested.
2589  * Returns 1 if this filesystem can be mounted as requested,
2590  * 0 if it cannot be.
2591  */
2592 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2593 {
2594         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2595                 ext4_msg(sb, KERN_ERR,
2596                         "Couldn't mount because of "
2597                         "unsupported optional features (%x)",
2598                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2599                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2600                 return 0;
2601         }
2602
2603         if (readonly)
2604                 return 1;
2605
2606         /* Check that feature set is OK for a read-write mount */
2607         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2608                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2609                          "unsupported optional features (%x)",
2610                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2611                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2612                 return 0;
2613         }
2614         /*
2615          * Large file size enabled file system can only be mounted
2616          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2617          */
2618         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2619                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2620                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2621                                  "cannot be mounted RDWR without "
2622                                  "CONFIG_LBDAF");
2623                         return 0;
2624                 }
2625         }
2626         return 1;
2627 }
2628
2629 /*
2630  * This function is called once a day if we have errors logged
2631  * on the file system
2632  */
2633 static void print_daily_error_info(unsigned long arg)
2634 {
2635         struct super_block *sb = (struct super_block *) arg;
2636         struct ext4_sb_info *sbi;
2637         struct ext4_super_block *es;
2638
2639         sbi = EXT4_SB(sb);
2640         es = sbi->s_es;
2641
2642         if (es->s_error_count)
2643                 ext4_msg(sb, KERN_NOTICE, "error count: %u",
2644                          le32_to_cpu(es->s_error_count));
2645         if (es->s_first_error_time) {
2646                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at %u: %.*s:%d",
2647                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2648                        (int) sizeof(es->s_first_error_func),
2649                        es->s_first_error_func,
2650                        le32_to_cpu(es->s_first_error_line));
2651                 if (es->s_first_error_ino)
2652                         printk(": inode %u",
2653                                le32_to_cpu(es->s_first_error_ino));
2654                 if (es->s_first_error_block)
2655                         printk(": block %llu", (unsigned long long)
2656                                le64_to_cpu(es->s_first_error_block));
2657                 printk("\n");
2658         }
2659         if (es->s_last_error_time) {
2660                 printk(KERN_NOTICE "EXT4-fs (%s): last error at %u: %.*s:%d",
2661                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2662                        (int) sizeof(es->s_last_error_func),
2663                        es->s_last_error_func,
2664                        le32_to_cpu(es->s_last_error_line));
2665                 if (es->s_last_error_ino)
2666                         printk(": inode %u",
2667                                le32_to_cpu(es->s_last_error_ino));
2668                 if (es->s_last_error_block)
2669                         printk(": block %llu", (unsigned long long)
2670                                le64_to_cpu(es->s_last_error_block));
2671                 printk("\n");
2672         }
2673         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2674 }
2675
2676 /* Find next suitable group and run ext4_init_inode_table */
2677 static int ext4_run_li_request(struct ext4_li_request *elr)
2678 {
2679         struct ext4_group_desc *gdp = NULL;
2680         ext4_group_t group, ngroups;
2681         struct super_block *sb;
2682         unsigned long timeout = 0;
2683         int ret = 0;
2684
2685         sb = elr->lr_super;
2686         ngroups = EXT4_SB(sb)->s_groups_count;
2687
2688         for (group = elr->lr_next_group; group < ngroups; group++) {
2689                 gdp = ext4_get_group_desc(sb, group, NULL);
2690                 if (!gdp) {
2691                         ret = 1;
2692                         break;
2693                 }
2694
2695                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2696                         break;
2697         }
2698
2699         if (group == ngroups)
2700                 ret = 1;
2701
2702         if (!ret) {
2703                 timeout = jiffies;
2704                 ret = ext4_init_inode_table(sb, group,
2705                                             elr->lr_timeout ? 0 : 1);
2706                 if (elr->lr_timeout == 0) {
2707                         timeout = (jiffies - timeout) *
2708                                   elr->lr_sbi->s_li_wait_mult;
2709                         elr->lr_timeout = timeout;
2710                 }
2711                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2712                 elr->lr_next_group = group + 1;
2713         }
2714
2715         return ret;
2716 }
2717
2718 /*
2719  * Remove lr_request from the list_request and free the
2720  * request structure. Should be called with li_list_mtx held
2721  */
2722 static void ext4_remove_li_request(struct ext4_li_request *elr)
2723 {
2724         struct ext4_sb_info *sbi;
2725
2726         if (!elr)
2727                 return;
2728
2729         sbi = elr->lr_sbi;
2730
2731         list_del(&elr->lr_request);
2732         sbi->s_li_request = NULL;
2733         kfree(elr);
2734 }
2735
2736 static void ext4_unregister_li_request(struct super_block *sb)
2737 {
2738         mutex_lock(&ext4_li_mtx);
2739         if (!ext4_li_info) {
2740                 mutex_unlock(&ext4_li_mtx);
2741                 return;
2742         }
2743
2744         mutex_lock(&ext4_li_info->li_list_mtx);
2745         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2746         mutex_unlock(&ext4_li_info->li_list_mtx);
2747         mutex_unlock(&ext4_li_mtx);
2748 }
2749
2750 static struct task_struct *ext4_lazyinit_task;
2751
2752 /*
2753  * This is the function where ext4lazyinit thread lives. It walks
2754  * through the request list searching for next scheduled filesystem.
2755  * When such a fs is found, run the lazy initialization request
2756  * (ext4_rn_li_request) and keep track of the time spend in this
2757  * function. Based on that time we compute next schedule time of
2758  * the request. When walking through the list is complete, compute
2759  * next waking time and put itself into sleep.
2760  */
2761 static int ext4_lazyinit_thread(void *arg)
2762 {
2763         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2764         struct list_head *pos, *n;
2765         struct ext4_li_request *elr;
2766         unsigned long next_wakeup, cur;
2767
2768         BUG_ON(NULL == eli);
2769
2770 cont_thread:
2771         while (true) {
2772                 next_wakeup = MAX_JIFFY_OFFSET;
2773
2774                 mutex_lock(&eli->li_list_mtx);
2775                 if (list_empty(&eli->li_request_list)) {
2776                         mutex_unlock(&eli->li_list_mtx);
2777                         goto exit_thread;
2778                 }
2779
2780                 list_for_each_safe(pos, n, &eli->li_request_list) {
2781                         elr = list_entry(pos, struct ext4_li_request,
2782                                          lr_request);
2783
2784                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2785                                 if (ext4_run_li_request(elr) != 0) {
2786                                         /* error, remove the lazy_init job */
2787                                         ext4_remove_li_request(elr);
2788                                         continue;
2789                                 }
2790                         }
2791
2792                         if (time_before(elr->lr_next_sched, next_wakeup))
2793                                 next_wakeup = elr->lr_next_sched;
2794                 }
2795                 mutex_unlock(&eli->li_list_mtx);
2796
2797                 if (freezing(current))
2798                         refrigerator();
2799
2800                 cur = jiffies;
2801                 if ((time_after_eq(cur, next_wakeup)) ||
2802                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2803                         cond_resched();
2804                         continue;
2805                 }
2806
2807                 schedule_timeout_interruptible(next_wakeup - cur);
2808
2809                 if (kthread_should_stop()) {
2810                         ext4_clear_request_list();
2811                         goto exit_thread;
2812                 }
2813         }
2814
2815 exit_thread:
2816         /*
2817          * It looks like the request list is empty, but we need
2818          * to check it under the li_list_mtx lock, to prevent any
2819          * additions into it, and of course we should lock ext4_li_mtx
2820          * to atomically free the list and ext4_li_info, because at
2821          * this point another ext4 filesystem could be registering
2822          * new one.
2823          */
2824         mutex_lock(&ext4_li_mtx);
2825         mutex_lock(&eli->li_list_mtx);
2826         if (!list_empty(&eli->li_request_list)) {
2827                 mutex_unlock(&eli->li_list_mtx);
2828                 mutex_unlock(&ext4_li_mtx);
2829                 goto cont_thread;
2830         }
2831         mutex_unlock(&eli->li_list_mtx);
2832         kfree(ext4_li_info);
2833         ext4_li_info = NULL;
2834         mutex_unlock(&ext4_li_mtx);
2835
2836         return 0;
2837 }
2838
2839 static void ext4_clear_request_list(void)
2840 {
2841         struct list_head *pos, *n;
2842         struct ext4_li_request *elr;
2843
2844         mutex_lock(&ext4_li_info->li_list_mtx);
2845         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2846                 elr = list_entry(pos, struct ext4_li_request,
2847                                  lr_request);
2848                 ext4_remove_li_request(elr);
2849         }
2850         mutex_unlock(&ext4_li_info->li_list_mtx);
2851 }
2852
2853 static int ext4_run_lazyinit_thread(void)
2854 {
2855         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
2856                                          ext4_li_info, "ext4lazyinit");
2857         if (IS_ERR(ext4_lazyinit_task)) {
2858                 int err = PTR_ERR(ext4_lazyinit_task);
2859                 ext4_clear_request_list();
2860                 kfree(ext4_li_info);
2861                 ext4_li_info = NULL;
2862                 printk(KERN_CRIT "EXT4: error %d creating inode table "
2863                                  "initialization thread\n",
2864                                  err);
2865                 return err;
2866         }
2867         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2868         return 0;
2869 }
2870
2871 /*
2872  * Check whether it make sense to run itable init. thread or not.
2873  * If there is at least one uninitialized inode table, return
2874  * corresponding group number, else the loop goes through all
2875  * groups and return total number of groups.
2876  */
2877 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2878 {
2879         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2880         struct ext4_group_desc *gdp = NULL;
2881
2882         for (group = 0; group < ngroups; group++) {
2883                 gdp = ext4_get_group_desc(sb, group, NULL);
2884                 if (!gdp)
2885                         continue;
2886
2887                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2888                         break;
2889         }
2890
2891         return group;
2892 }
2893
2894 static int ext4_li_info_new(void)
2895 {
2896         struct ext4_lazy_init *eli = NULL;
2897
2898         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2899         if (!eli)
2900                 return -ENOMEM;
2901
2902         INIT_LIST_HEAD(&eli->li_request_list);
2903         mutex_init(&eli->li_list_mtx);
2904
2905         eli->li_state |= EXT4_LAZYINIT_QUIT;
2906
2907         ext4_li_info = eli;
2908
2909         return 0;
2910 }
2911
2912 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2913                                             ext4_group_t start)
2914 {
2915         struct ext4_sb_info *sbi = EXT4_SB(sb);
2916         struct ext4_li_request *elr;
2917         unsigned long rnd;
2918
2919         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
2920         if (!elr)
2921                 return NULL;
2922
2923         elr->lr_super = sb;
2924         elr->lr_sbi = sbi;
2925         elr->lr_next_group = start;
2926
2927         /*
2928          * Randomize first schedule time of the request to
2929          * spread the inode table initialization requests
2930          * better.
2931          */
2932         get_random_bytes(&rnd, sizeof(rnd));
2933         elr->lr_next_sched = jiffies + (unsigned long)rnd %
2934                              (EXT4_DEF_LI_MAX_START_DELAY * HZ);
2935
2936         return elr;
2937 }
2938
2939 static int ext4_register_li_request(struct super_block *sb,
2940                                     ext4_group_t first_not_zeroed)
2941 {
2942         struct ext4_sb_info *sbi = EXT4_SB(sb);
2943         struct ext4_li_request *elr;
2944         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
2945         int ret = 0;
2946
2947         if (sbi->s_li_request != NULL) {
2948                 /*
2949                  * Reset timeout so it can be computed again, because
2950                  * s_li_wait_mult might have changed.
2951                  */
2952                 sbi->s_li_request->lr_timeout = 0;
2953                 return 0;
2954         }
2955
2956         if (first_not_zeroed == ngroups ||
2957             (sb->s_flags & MS_RDONLY) ||
2958             !test_opt(sb, INIT_INODE_TABLE))
2959                 return 0;
2960
2961         elr = ext4_li_request_new(sb, first_not_zeroed);
2962         if (!elr)
2963                 return -ENOMEM;
2964
2965         mutex_lock(&ext4_li_mtx);
2966
2967         if (NULL == ext4_li_info) {
2968                 ret = ext4_li_info_new();
2969                 if (ret)
2970                         goto out;
2971         }
2972
2973         mutex_lock(&ext4_li_info->li_list_mtx);
2974         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
2975         mutex_unlock(&ext4_li_info->li_list_mtx);
2976
2977         sbi->s_li_request = elr;
2978         /*
2979          * set elr to NULL here since it has been inserted to
2980          * the request_list and the removal and free of it is
2981          * handled by ext4_clear_request_list from now on.
2982          */
2983         elr = NULL;
2984
2985         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
2986                 ret = ext4_run_lazyinit_thread();
2987                 if (ret)
2988                         goto out;
2989         }
2990 out:
2991         mutex_unlock(&ext4_li_mtx);
2992         if (ret)
2993                 kfree(elr);
2994         return ret;
2995 }
2996
2997 /*
2998  * We do not need to lock anything since this is called on
2999  * module unload.
3000  */
3001 static void ext4_destroy_lazyinit_thread(void)
3002 {
3003         /*
3004          * If thread exited earlier
3005          * there's nothing to be done.
3006          */
3007         if (!ext4_li_info || !ext4_lazyinit_task)
3008                 return;
3009
3010         kthread_stop(ext4_lazyinit_task);
3011 }
3012
3013 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3014                                 __releases(kernel_lock)
3015                                 __acquires(kernel_lock)
3016 {
3017         char *orig_data = kstrdup(data, GFP_KERNEL);
3018         struct buffer_head *bh;
3019         struct ext4_super_block *es = NULL;
3020         struct ext4_sb_info *sbi;
3021         ext4_fsblk_t block;
3022         ext4_fsblk_t sb_block = get_sb_block(&data);
3023         ext4_fsblk_t logical_sb_block;
3024         unsigned long offset = 0;
3025         unsigned long journal_devnum = 0;
3026         unsigned long def_mount_opts;
3027         struct inode *root;
3028         char *cp;
3029         const char *descr;
3030         int ret = -ENOMEM;
3031         int blocksize;
3032         unsigned int db_count;
3033         unsigned int i;
3034         int needs_recovery, has_huge_files;
3035         __u64 blocks_count;
3036         int err;
3037         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3038         ext4_group_t first_not_zeroed;
3039
3040         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3041         if (!sbi)
3042                 goto out_free_orig;
3043
3044         sbi->s_blockgroup_lock =
3045                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3046         if (!sbi->s_blockgroup_lock) {
3047                 kfree(sbi);
3048                 goto out_free_orig;
3049         }
3050         sb->s_fs_info = sbi;
3051         sbi->s_mount_opt = 0;
3052         sbi->s_resuid = EXT4_DEF_RESUID;
3053         sbi->s_resgid = EXT4_DEF_RESGID;
3054         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3055         sbi->s_sb_block = sb_block;
3056         if (sb->s_bdev->bd_part)
3057                 sbi->s_sectors_written_start =
3058                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3059
3060         /* Cleanup superblock name */
3061         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3062                 *cp = '!';
3063
3064         ret = -EINVAL;
3065         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3066         if (!blocksize) {
3067                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3068                 goto out_fail;
3069         }
3070
3071         /*
3072          * The ext4 superblock will not be buffer aligned for other than 1kB
3073          * block sizes.  We need to calculate the offset from buffer start.
3074          */
3075         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3076                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3077                 offset = do_div(logical_sb_block, blocksize);
3078         } else {
3079                 logical_sb_block = sb_block;
3080         }
3081
3082         if (!(bh = sb_bread(sb, logical_sb_block))) {
3083                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3084                 goto out_fail;
3085         }
3086         /*
3087          * Note: s_es must be initialized as soon as possible because
3088          *       some ext4 macro-instructions depend on its value
3089          */
3090         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3091         sbi->s_es = es;
3092         sb->s_magic = le16_to_cpu(es->s_magic);
3093         if (sb->s_magic != EXT4_SUPER_MAGIC)
3094                 goto cantfind_ext4;
3095         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3096
3097         /* Set defaults before we parse the mount options */
3098         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3099         set_opt(sb, INIT_INODE_TABLE);
3100         if (def_mount_opts & EXT4_DEFM_DEBUG)
3101                 set_opt(sb, DEBUG);
3102         if (def_mount_opts & EXT4_DEFM_BSDGROUPS) {
3103                 ext4_msg(sb, KERN_WARNING, deprecated_msg, "bsdgroups",
3104                         "2.6.38");
3105                 set_opt(sb, GRPID);
3106         }
3107         if (def_mount_opts & EXT4_DEFM_UID16)
3108                 set_opt(sb, NO_UID32);
3109         /* xattr user namespace & acls are now defaulted on */
3110 #ifdef CONFIG_EXT4_FS_XATTR
3111         set_opt(sb, XATTR_USER);
3112 #endif
3113 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3114         set_opt(sb, POSIX_ACL);
3115 #endif
3116         set_opt(sb, MBLK_IO_SUBMIT);
3117         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3118                 set_opt(sb, JOURNAL_DATA);
3119         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3120                 set_opt(sb, ORDERED_DATA);
3121         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3122                 set_opt(sb, WRITEBACK_DATA);
3123
3124         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3125                 set_opt(sb, ERRORS_PANIC);
3126         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3127                 set_opt(sb, ERRORS_CONT);
3128         else
3129                 set_opt(sb, ERRORS_RO);
3130         if (def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY)
3131                 set_opt(sb, BLOCK_VALIDITY);
3132         if (def_mount_opts & EXT4_DEFM_DISCARD)
3133                 set_opt(sb, DISCARD);
3134
3135         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
3136         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
3137         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3138         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3139         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3140
3141         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3142                 set_opt(sb, BARRIER);
3143
3144         /*
3145          * enable delayed allocation by default
3146          * Use -o nodelalloc to turn it off
3147          */
3148         if (!IS_EXT3_SB(sb) &&
3149             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3150                 set_opt(sb, DELALLOC);
3151
3152         /*
3153          * set default s_li_wait_mult for lazyinit, for the case there is
3154          * no mount option specified.
3155          */
3156         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3157
3158         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3159                            &journal_devnum, &journal_ioprio, NULL, 0)) {
3160                 ext4_msg(sb, KERN_WARNING,
3161                          "failed to parse options in superblock: %s",
3162                          sbi->s_es->s_mount_opts);
3163         }
3164         if (!parse_options((char *) data, sb, &journal_devnum,
3165                            &journal_ioprio, NULL, 0))
3166                 goto failed_mount;
3167
3168         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3169                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3170
3171         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3172             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3173              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3174              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3175                 ext4_msg(sb, KERN_WARNING,
3176                        "feature flags set on rev 0 fs, "
3177                        "running e2fsck is recommended");
3178
3179         if (IS_EXT2_SB(sb)) {
3180                 if (ext2_feature_set_ok(sb))
3181                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3182                                  "using the ext4 subsystem");
3183                 else {
3184                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3185                                  "to feature incompatibilities");
3186                         goto failed_mount;
3187                 }
3188         }
3189
3190         if (IS_EXT3_SB(sb)) {
3191                 if (ext3_feature_set_ok(sb))
3192                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3193                                  "using the ext4 subsystem");
3194                 else {
3195                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3196                                  "to feature incompatibilities");
3197                         goto failed_mount;
3198                 }
3199         }
3200
3201         /*
3202          * Check feature flags regardless of the revision level, since we
3203          * previously didn't change the revision level when setting the flags,
3204          * so there is a chance incompat flags are set on a rev 0 filesystem.
3205          */
3206         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3207                 goto failed_mount;
3208
3209         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3210
3211         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3212             blocksize > EXT4_MAX_BLOCK_SIZE) {
3213                 ext4_msg(sb, KERN_ERR,
3214                        "Unsupported filesystem blocksize %d", blocksize);
3215                 goto failed_mount;
3216         }
3217
3218         if (sb->s_blocksize != blocksize) {
3219                 /* Validate the filesystem blocksize */
3220                 if (!sb_set_blocksize(sb, blocksize)) {
3221                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3222                                         blocksize);
3223                         goto failed_mount;
3224                 }
3225
3226                 brelse(bh);
3227                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3228                 offset = do_div(logical_sb_block, blocksize);
3229                 bh = sb_bread(sb, logical_sb_block);
3230                 if (!bh) {
3231                         ext4_msg(sb, KERN_ERR,
3232                                "Can't read superblock on 2nd try");
3233                         goto failed_mount;
3234                 }
3235                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
3236                 sbi->s_es = es;
3237                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3238                         ext4_msg(sb, KERN_ERR,
3239                                "Magic mismatch, very weird!");
3240                         goto failed_mount;
3241                 }
3242         }
3243
3244         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3245                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3246         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3247                                                       has_huge_files);
3248         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3249
3250         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3251                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3252                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3253         } else {
3254                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3255                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3256                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3257                     (!is_power_of_2(sbi->s_inode_size)) ||
3258                     (sbi->s_inode_size > blocksize)) {
3259                         ext4_msg(sb, KERN_ERR,
3260                                "unsupported inode size: %d",
3261                                sbi->s_inode_size);
3262                         goto failed_mount;
3263                 }
3264                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3265                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3266         }
3267
3268         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3269         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3270                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3271                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3272                     !is_power_of_2(sbi->s_desc_size)) {
3273                         ext4_msg(sb, KERN_ERR,
3274                                "unsupported descriptor size %lu",
3275                                sbi->s_desc_size);
3276                         goto failed_mount;
3277                 }
3278         } else
3279                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3280
3281         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3282         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3283         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3284                 goto cantfind_ext4;
3285
3286         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3287         if (sbi->s_inodes_per_block == 0)
3288                 goto cantfind_ext4;
3289         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3290                                         sbi->s_inodes_per_block;
3291         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3292         sbi->s_sbh = bh;
3293         sbi->s_mount_state = le16_to_cpu(es->s_state);
3294         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3295         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3296
3297         for (i = 0; i < 4; i++)
3298                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3299         sbi->s_def_hash_version = es->s_def_hash_version;
3300         i = le32_to_cpu(es->s_flags);
3301         if (i & EXT2_FLAGS_UNSIGNED_HASH)
3302                 sbi->s_hash_unsigned = 3;
3303         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3304 #ifdef __CHAR_UNSIGNED__
3305                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3306                 sbi->s_hash_unsigned = 3;
3307 #else
3308                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3309 #endif
3310                 sb->s_dirt = 1;
3311         }
3312
3313         if (sbi->s_blocks_per_group > blocksize * 8) {
3314                 ext4_msg(sb, KERN_ERR,
3315                        "#blocks per group too big: %lu",
3316                        sbi->s_blocks_per_group);
3317                 goto failed_mount;
3318         }
3319         if (sbi->s_inodes_per_group > blocksize * 8) {
3320                 ext4_msg(sb, KERN_ERR,
3321                        "#inodes per group too big: %lu",
3322                        sbi->s_inodes_per_group);
3323                 goto failed_mount;
3324         }
3325
3326         /*
3327          * Test whether we have more sectors than will fit in sector_t,
3328          * and whether the max offset is addressable by the page cache.
3329          */
3330         err = generic_check_addressable(sb->s_blocksize_bits,
3331                                         ext4_blocks_count(es));
3332         if (err) {
3333                 ext4_msg(sb, KERN_ERR, "filesystem"
3334                          " too large to mount safely on this system");
3335                 if (sizeof(sector_t) < 8)
3336                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3337                 ret = err;
3338                 goto failed_mount;
3339         }
3340
3341         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3342                 goto cantfind_ext4;
3343
3344         /* check blocks count against device size */
3345         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3346         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3347                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3348                        "exceeds size of device (%llu blocks)",
3349                        ext4_blocks_count(es), blocks_count);
3350                 goto failed_mount;
3351         }
3352
3353         /*
3354          * It makes no sense for the first data block to be beyond the end
3355          * of the filesystem.
3356          */
3357         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3358                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data"
3359                          "block %u is beyond end of filesystem (%llu)",
3360                          le32_to_cpu(es->s_first_data_block),
3361                          ext4_blocks_count(es));
3362                 goto failed_mount;
3363         }
3364         blocks_count = (ext4_blocks_count(es) -
3365                         le32_to_cpu(es->s_first_data_block) +
3366                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3367         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3368         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3369                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3370                        "(block count %llu, first data block %u, "
3371                        "blocks per group %lu)", sbi->s_groups_count,
3372                        ext4_blocks_count(es),
3373                        le32_to_cpu(es->s_first_data_block),
3374                        EXT4_BLOCKS_PER_GROUP(sb));
3375                 goto failed_mount;
3376         }
3377         sbi->s_groups_count = blocks_count;
3378         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3379                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3380         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3381                    EXT4_DESC_PER_BLOCK(sb);
3382         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
3383                                     GFP_KERNEL);
3384         if (sbi->s_group_desc == NULL) {
3385                 ext4_msg(sb, KERN_ERR, "not enough memory");
3386                 goto failed_mount;
3387         }
3388
3389 #ifdef CONFIG_PROC_FS
3390         if (ext4_proc_root)
3391                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
3392 #endif
3393
3394         bgl_lock_init(sbi->s_blockgroup_lock);
3395
3396         for (i = 0; i < db_count; i++) {
3397                 block = descriptor_loc(sb, logical_sb_block, i);
3398                 sbi->s_group_desc[i] = sb_bread(sb, block);
3399                 if (!sbi->s_group_desc[i]) {
3400                         ext4_msg(sb, KERN_ERR,
3401                                "can't read group descriptor %d", i);
3402                         db_count = i;
3403                         goto failed_mount2;
3404                 }
3405         }
3406         if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3407                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3408                 goto failed_mount2;
3409         }
3410         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
3411                 if (!ext4_fill_flex_info(sb)) {
3412                         ext4_msg(sb, KERN_ERR,
3413                                "unable to initialize "
3414                                "flex_bg meta info!");
3415                         goto failed_mount2;
3416                 }
3417
3418         sbi->s_gdb_count = db_count;
3419         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3420         spin_lock_init(&sbi->s_next_gen_lock);
3421
3422         init_timer(&sbi->s_err_report);
3423         sbi->s_err_report.function = print_daily_error_info;
3424         sbi->s_err_report.data = (unsigned long) sb;
3425
3426         err = percpu_counter_init(&sbi->s_freeblocks_counter,
3427                         ext4_count_free_blocks(sb));
3428         if (!err) {
3429                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
3430                                 ext4_count_free_inodes(sb));
3431         }
3432         if (!err) {
3433                 err = percpu_counter_init(&sbi->s_dirs_counter,
3434                                 ext4_count_dirs(sb));
3435         }
3436         if (!err) {
3437                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
3438         }
3439         if (err) {
3440                 ext4_msg(sb, KERN_ERR, "insufficient memory");
3441                 goto failed_mount3;
3442         }
3443
3444         sbi->s_stripe = ext4_get_stripe_size(sbi);
3445         sbi->s_max_writeback_mb_bump = 128;
3446
3447         /*
3448          * set up enough so that it can read an inode
3449          */
3450         if (!test_opt(sb, NOLOAD) &&
3451             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
3452                 sb->s_op = &ext4_sops;
3453         else
3454                 sb->s_op = &ext4_nojournal_sops;
3455         sb->s_export_op = &ext4_export_ops;
3456         sb->s_xattr = ext4_xattr_handlers;
3457 #ifdef CONFIG_QUOTA
3458         sb->s_qcop = &ext4_qctl_operations;
3459         sb->dq_op = &ext4_quota_operations;
3460 #endif
3461         memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
3462
3463         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
3464         mutex_init(&sbi->s_orphan_lock);
3465         mutex_init(&sbi->s_resize_lock);
3466
3467         sb->s_root = NULL;
3468
3469         needs_recovery = (es->s_last_orphan != 0 ||
3470                           EXT4_HAS_INCOMPAT_FEATURE(sb,
3471                                     EXT4_FEATURE_INCOMPAT_RECOVER));
3472
3473         /*
3474          * The first inode we look at is the journal inode.  Don't try
3475          * root first: it may be modified in the journal!
3476          */
3477         if (!test_opt(sb, NOLOAD) &&
3478             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3479                 if (ext4_load_journal(sb, es, journal_devnum))
3480                         goto failed_mount3;
3481         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
3482               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3483                 ext4_msg(sb, KERN_ERR, "required journal recovery "
3484                        "suppressed and not mounted read-only");
3485                 goto failed_mount_wq;
3486         } else {
3487                 clear_opt(sb, DATA_FLAGS);
3488                 sbi->s_journal = NULL;
3489                 needs_recovery = 0;
3490                 goto no_journal;
3491         }
3492
3493         if (ext4_blocks_count(es) > 0xffffffffULL &&
3494             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
3495                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
3496                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
3497                 goto failed_mount_wq;
3498         }
3499
3500         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3501                 jbd2_journal_set_features(sbi->s_journal,
3502                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3503                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3504         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3505                 jbd2_journal_set_features(sbi->s_journal,
3506                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
3507                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3508                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3509         } else {
3510                 jbd2_journal_clear_features(sbi->s_journal,
3511                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3512                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3513         }
3514
3515         /* We have now updated the journal if required, so we can
3516          * validate the data journaling mode. */
3517         switch (test_opt(sb, DATA_FLAGS)) {
3518         case 0:
3519                 /* No mode set, assume a default based on the journal
3520                  * capabilities: ORDERED_DATA if the journal can
3521                  * cope, else JOURNAL_DATA
3522                  */
3523                 if (jbd2_journal_check_available_features
3524                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
3525                         set_opt(sb, ORDERED_DATA);
3526                 else
3527                         set_opt(sb, JOURNAL_DATA);
3528                 break;
3529
3530         case EXT4_MOUNT_ORDERED_DATA:
3531         case EXT4_MOUNT_WRITEBACK_DATA:
3532                 if (!jbd2_journal_check_available_features
3533                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
3534                         ext4_msg(sb, KERN_ERR, "Journal does not support "
3535                                "requested data journaling mode");
3536                         goto failed_mount_wq;
3537                 }
3538         default:
3539                 break;
3540         }
3541         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3542
3543         /*
3544          * The journal may have updated the bg summary counts, so we
3545          * need to update the global counters.
3546          */
3547         percpu_counter_set(&sbi->s_freeblocks_counter,
3548                            ext4_count_free_blocks(sb));
3549         percpu_counter_set(&sbi->s_freeinodes_counter,
3550                            ext4_count_free_inodes(sb));
3551         percpu_counter_set(&sbi->s_dirs_counter,
3552                            ext4_count_dirs(sb));
3553         percpu_counter_set(&sbi->s_dirtyblocks_counter, 0);
3554
3555 no_journal:
3556         /*
3557          * The maximum number of concurrent works can be high and
3558          * concurrency isn't really necessary.  Limit it to 1.
3559          */
3560         EXT4_SB(sb)->dio_unwritten_wq =
3561                 alloc_workqueue("ext4-dio-unwritten", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
3562         if (!EXT4_SB(sb)->dio_unwritten_wq) {
3563                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
3564                 goto failed_mount_wq;
3565         }
3566
3567         /*
3568          * The jbd2_journal_load will have done any necessary log recovery,
3569          * so we can safely mount the rest of the filesystem now.
3570          */
3571
3572         root = ext4_iget(sb, EXT4_ROOT_INO);
3573         if (IS_ERR(root)) {
3574                 ext4_msg(sb, KERN_ERR, "get root inode failed");
3575                 ret = PTR_ERR(root);
3576                 root = NULL;
3577                 goto failed_mount4;
3578         }
3579         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
3580                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
3581                 goto failed_mount4;
3582         }
3583         sb->s_root = d_alloc_root(root);
3584         if (!sb->s_root) {
3585                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
3586                 ret = -ENOMEM;
3587                 goto failed_mount4;
3588         }
3589
3590         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
3591
3592         /* determine the minimum size of new large inodes, if present */
3593         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3594                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3595                                                      EXT4_GOOD_OLD_INODE_SIZE;
3596                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3597                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
3598                         if (sbi->s_want_extra_isize <
3599                             le16_to_cpu(es->s_want_extra_isize))
3600                                 sbi->s_want_extra_isize =
3601                                         le16_to_cpu(es->s_want_extra_isize);
3602                         if (sbi->s_want_extra_isize <
3603                             le16_to_cpu(es->s_min_extra_isize))
3604                                 sbi->s_want_extra_isize =
3605                                         le16_to_cpu(es->s_min_extra_isize);
3606                 }
3607         }
3608         /* Check if enough inode space is available */
3609         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3610                                                         sbi->s_inode_size) {
3611                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3612                                                        EXT4_GOOD_OLD_INODE_SIZE;
3613                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
3614                          "available");
3615         }
3616
3617         if (test_opt(sb, DELALLOC) &&
3618             (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
3619                 ext4_msg(sb, KERN_WARNING, "Ignoring delalloc option - "
3620                          "requested data journaling mode");
3621                 clear_opt(sb, DELALLOC);
3622         }
3623         if (test_opt(sb, DIOREAD_NOLOCK)) {
3624                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3625                         ext4_msg(sb, KERN_WARNING, "Ignoring dioread_nolock "
3626                                 "option - requested data journaling mode");
3627                         clear_opt(sb, DIOREAD_NOLOCK);
3628                 }
3629                 if (sb->s_blocksize < PAGE_SIZE) {
3630                         ext4_msg(sb, KERN_WARNING, "Ignoring dioread_nolock "
3631                                 "option - block size is too small");
3632                         clear_opt(sb, DIOREAD_NOLOCK);
3633                 }
3634         }
3635
3636         err = ext4_setup_system_zone(sb);
3637         if (err) {
3638                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
3639                          "zone (%d)", err);
3640                 goto failed_mount4;
3641         }
3642
3643         ext4_ext_init(sb);
3644         err = ext4_mb_init(sb, needs_recovery);
3645         if (err) {
3646                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
3647                          err);
3648                 goto failed_mount4;
3649         }
3650
3651         err = ext4_register_li_request(sb, first_not_zeroed);
3652         if (err)
3653                 goto failed_mount4;
3654
3655         sbi->s_kobj.kset = ext4_kset;
3656         init_completion(&sbi->s_kobj_unregister);
3657         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
3658                                    "%s", sb->s_id);
3659         if (err) {
3660                 ext4_mb_release(sb);
3661                 ext4_ext_release(sb);
3662                 goto failed_mount4;
3663         };
3664
3665         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
3666         ext4_orphan_cleanup(sb, es);
3667         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
3668         if (needs_recovery) {
3669                 ext4_msg(sb, KERN_INFO, "recovery complete");
3670                 ext4_mark_recovery_complete(sb, es);
3671         }
3672         if (EXT4_SB(sb)->s_journal) {
3673                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3674                         descr = " journalled data mode";
3675                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3676                         descr = " ordered data mode";
3677                 else
3678                         descr = " writeback data mode";
3679         } else
3680                 descr = "out journal";
3681
3682         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
3683                  "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
3684                  *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
3685
3686         if (es->s_error_count)
3687                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
3688
3689         kfree(orig_data);
3690         return 0;
3691
3692 cantfind_ext4:
3693         if (!silent)
3694                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
3695         goto failed_mount;
3696
3697 failed_mount4:
3698         iput(root);
3699         sb->s_root = NULL;
3700         ext4_msg(sb, KERN_ERR, "mount failed");
3701         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
3702 failed_mount_wq:
3703         ext4_release_system_zone(sb);
3704         if (sbi->s_journal) {
3705                 jbd2_journal_destroy(sbi->s_journal);
3706                 sbi->s_journal = NULL;
3707         }
3708 failed_mount3:
3709         del_timer(&sbi->s_err_report);
3710         if (sbi->s_flex_groups) {
3711                 if (is_vmalloc_addr(sbi->s_flex_groups))
3712                         vfree(sbi->s_flex_groups);
3713                 else
3714                         kfree(sbi->s_flex_groups);
3715         }
3716         percpu_counter_destroy(&sbi->s_freeblocks_counter);
3717         percpu_counter_destroy(&sbi->s_freeinodes_counter);
3718         percpu_counter_destroy(&sbi->s_dirs_counter);
3719         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
3720 failed_mount2:
3721         for (i = 0; i < db_count; i++)
3722                 brelse(sbi->s_group_desc[i]);
3723         kfree(sbi->s_group_desc);
3724 failed_mount:
3725         if (sbi->s_proc) {
3726                 remove_proc_entry(sb->s_id, ext4_proc_root);
3727         }
3728 #ifdef CONFIG_QUOTA
3729         for (i = 0; i < MAXQUOTAS; i++)
3730                 kfree(sbi->s_qf_names[i]);
3731 #endif
3732         ext4_blkdev_remove(sbi);
3733         brelse(bh);
3734 out_fail:
3735         sb->s_fs_info = NULL;
3736         kfree(sbi->s_blockgroup_lock);
3737         kfree(sbi);
3738 out_free_orig:
3739         kfree(orig_data);
3740         return ret;
3741 }
3742
3743 /*
3744  * Setup any per-fs journal parameters now.  We'll do this both on
3745  * initial mount, once the journal has been initialised but before we've
3746  * done any recovery; and again on any subsequent remount.
3747  */
3748 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
3749 {
3750         struct ext4_sb_info *sbi = EXT4_SB(sb);
3751
3752         journal->j_commit_interval = sbi->s_commit_interval;
3753         journal->j_min_batch_time = sbi->s_min_batch_time;
3754         journal->j_max_batch_time = sbi->s_max_batch_time;
3755
3756         write_lock(&journal->j_state_lock);
3757         if (test_opt(sb, BARRIER))
3758                 journal->j_flags |= JBD2_BARRIER;
3759         else
3760                 journal->j_flags &= ~JBD2_BARRIER;
3761         if (test_opt(sb, DATA_ERR_ABORT))
3762                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
3763         else
3764                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
3765         write_unlock(&journal->j_state_lock);
3766 }
3767
3768 static journal_t *ext4_get_journal(struct super_block *sb,
3769                                    unsigned int journal_inum)
3770 {
3771         struct inode *journal_inode;
3772         journal_t *journal;
3773
3774         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3775
3776         /* First, test for the existence of a valid inode on disk.  Bad
3777          * things happen if we iget() an unused inode, as the subsequent
3778          * iput() will try to delete it. */
3779
3780         journal_inode = ext4_iget(sb, journal_inum);
3781         if (IS_ERR(journal_inode)) {
3782                 ext4_msg(sb, KERN_ERR, "no journal found");
3783                 return NULL;
3784         }
3785         if (!journal_inode->i_nlink) {
3786                 make_bad_inode(journal_inode);
3787                 iput(journal_inode);
3788                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
3789                 return NULL;
3790         }
3791
3792         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
3793                   journal_inode, journal_inode->i_size);
3794         if (!S_ISREG(journal_inode->i_mode)) {
3795                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
3796                 iput(journal_inode);
3797                 return NULL;
3798         }
3799
3800         journal = jbd2_journal_init_inode(journal_inode);
3801         if (!journal) {
3802                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
3803                 iput(journal_inode);
3804                 return NULL;
3805         }
3806         journal->j_private = sb;
3807         ext4_init_journal_params(sb, journal);
3808         return journal;
3809 }
3810
3811 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3812                                        dev_t j_dev)
3813 {
3814         struct buffer_head *bh;
3815         journal_t *journal;
3816         ext4_fsblk_t start;
3817         ext4_fsblk_t len;
3818         int hblock, blocksize;
3819         ext4_fsblk_t sb_block;
3820         unsigned long offset;
3821         struct ext4_super_block *es;
3822         struct block_device *bdev;
3823
3824         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3825
3826         bdev = ext4_blkdev_get(j_dev, sb);
3827         if (bdev == NULL)
3828                 return NULL;
3829
3830         blocksize = sb->s_blocksize;
3831         hblock = bdev_logical_block_size(bdev);
3832         if (blocksize < hblock) {
3833                 ext4_msg(sb, KERN_ERR,
3834                         "blocksize too small for journal device");
3835                 goto out_bdev;
3836         }
3837
3838         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3839         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3840         set_blocksize(bdev, blocksize);
3841         if (!(bh = __bread(bdev, sb_block, blocksize))) {
3842                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
3843                        "external journal");
3844                 goto out_bdev;
3845         }
3846
3847         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3848         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
3849             !(le32_to_cpu(es->s_feature_incompat) &
3850               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
3851                 ext4_msg(sb, KERN_ERR, "external journal has "
3852                                         "bad superblock");
3853                 brelse(bh);
3854                 goto out_bdev;
3855         }
3856
3857         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
3858                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
3859                 brelse(bh);
3860                 goto out_bdev;
3861         }
3862
3863         len = ext4_blocks_count(es);
3864         start = sb_block + 1;
3865         brelse(bh);     /* we're done with the superblock */
3866
3867         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
3868                                         start, len, blocksize);
3869         if (!journal) {
3870                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
3871                 goto out_bdev;
3872         }
3873         journal->j_private = sb;
3874         ll_rw_block(READ, 1, &journal->j_sb_buffer);
3875         wait_on_buffer(journal->j_sb_buffer);
3876         if (!buffer_uptodate(journal->j_sb_buffer)) {
3877                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
3878                 goto out_journal;
3879         }
3880         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
3881                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
3882                                         "user (unsupported) - %d",
3883                         be32_to_cpu(journal->j_superblock->s_nr_users));
3884                 goto out_journal;
3885         }
3886         EXT4_SB(sb)->journal_bdev = bdev;
3887         ext4_init_journal_params(sb, journal);
3888         return journal;
3889
3890 out_journal:
3891         jbd2_journal_destroy(journal);
3892 out_bdev:
3893         ext4_blkdev_put(bdev);
3894         return NULL;
3895 }
3896
3897 static int ext4_load_journal(struct super_block *sb,
3898                              struct ext4_super_block *es,
3899                              unsigned long journal_devnum)
3900 {
3901         journal_t *journal;
3902         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
3903         dev_t journal_dev;
3904         int err = 0;
3905         int really_read_only;
3906
3907         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3908
3909         if (journal_devnum &&
3910             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3911                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
3912                         "numbers have changed");
3913                 journal_dev = new_decode_dev(journal_devnum);
3914         } else
3915                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
3916
3917         really_read_only = bdev_read_only(sb->s_bdev);
3918
3919         /*
3920          * Are we loading a blank journal or performing recovery after a
3921          * crash?  For recovery, we need to check in advance whether we
3922          * can get read-write access to the device.
3923          */
3924         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3925                 if (sb->s_flags & MS_RDONLY) {
3926                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
3927                                         "required on readonly filesystem");
3928                         if (really_read_only) {
3929                                 ext4_msg(sb, KERN_ERR, "write access "
3930                                         "unavailable, cannot proceed");
3931                                 return -EROFS;
3932                         }
3933                         ext4_msg(sb, KERN_INFO, "write access will "
3934                                "be enabled during recovery");
3935                 }
3936         }
3937
3938         if (journal_inum && journal_dev) {
3939                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
3940                        "and inode journals!");
3941                 return -EINVAL;
3942         }
3943
3944         if (journal_inum) {
3945                 if (!(journal = ext4_get_journal(sb, journal_inum)))
3946                         return -EINVAL;
3947         } else {
3948                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
3949                         return -EINVAL;
3950         }
3951
3952         if (!(journal->j_flags & JBD2_BARRIER))
3953                 ext4_msg(sb, KERN_INFO, "barriers disabled");
3954
3955         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
3956                 err = jbd2_journal_update_format(journal);
3957                 if (err)  {
3958                         ext4_msg(sb, KERN_ERR, "error updating journal");
3959                         jbd2_journal_destroy(journal);
3960                         return err;
3961                 }
3962         }
3963
3964         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
3965                 err = jbd2_journal_wipe(journal, !really_read_only);
3966         if (!err) {
3967                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
3968                 if (save)
3969                         memcpy(save, ((char *) es) +
3970                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
3971                 err = jbd2_journal_load(journal);
3972                 if (save)
3973                         memcpy(((char *) es) + EXT4_S_ERR_START,
3974                                save, EXT4_S_ERR_LEN);
3975                 kfree(save);
3976         }
3977
3978         if (err) {
3979                 ext4_msg(sb, KERN_ERR, "error loading journal");
3980                 jbd2_journal_destroy(journal);
3981                 return err;
3982         }
3983
3984         EXT4_SB(sb)->s_journal = journal;
3985         ext4_clear_journal_err(sb, es);
3986
3987         if (!really_read_only && journal_devnum &&
3988             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3989                 es->s_journal_dev = cpu_to_le32(journal_devnum);
3990
3991                 /* Make sure we flush the recovery flag to disk. */
3992                 ext4_commit_super(sb, 1);
3993         }
3994
3995         return 0;
3996 }
3997
3998 static int ext4_commit_super(struct super_block *sb, int sync)
3999 {
4000         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4001         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4002         int error = 0;
4003
4004         if (!sbh)
4005                 return error;
4006         if (buffer_write_io_error(sbh)) {
4007                 /*
4008                  * Oh, dear.  A previous attempt to write the
4009                  * superblock failed.  This could happen because the
4010                  * USB device was yanked out.  Or it could happen to
4011                  * be a transient write error and maybe the block will
4012                  * be remapped.  Nothing we can do but to retry the
4013                  * write and hope for the best.
4014                  */
4015                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4016                        "superblock detected");
4017                 clear_buffer_write_io_error(sbh);
4018                 set_buffer_uptodate(sbh);
4019         }
4020         /*
4021          * If the file system is mounted read-only, don't update the
4022          * superblock write time.  This avoids updating the superblock
4023          * write time when we are mounting the root file system
4024          * read/only but we need to replay the journal; at that point,
4025          * for people who are east of GMT and who make their clock
4026          * tick in localtime for Windows bug-for-bug compatibility,
4027          * the clock is set in the future, and this will cause e2fsck
4028          * to complain and force a full file system check.
4029          */
4030         if (!(sb->s_flags & MS_RDONLY))
4031                 es->s_wtime = cpu_to_le32(get_seconds());
4032         if (sb->s_bdev->bd_part)
4033                 es->s_kbytes_written =
4034                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4035                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4036                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4037         else
4038                 es->s_kbytes_written =
4039                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4040         ext4_free_blocks_count_set(es, percpu_counter_sum_positive(
4041                                            &EXT4_SB(sb)->s_freeblocks_counter));
4042         es->s_free_inodes_count =
4043                 cpu_to_le32(percpu_counter_sum_positive(
4044                                 &EXT4_SB(sb)->s_freeinodes_counter));
4045         sb->s_dirt = 0;
4046         BUFFER_TRACE(sbh, "marking dirty");
4047         mark_buffer_dirty(sbh);
4048         if (sync) {
4049                 error = sync_dirty_buffer(sbh);
4050                 if (error)
4051                         return error;
4052
4053                 error = buffer_write_io_error(sbh);
4054                 if (error) {
4055                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4056                                "superblock");
4057                         clear_buffer_write_io_error(sbh);
4058                         set_buffer_uptodate(sbh);
4059                 }
4060         }
4061         return error;
4062 }
4063
4064 /*
4065  * Have we just finished recovery?  If so, and if we are mounting (or
4066  * remounting) the filesystem readonly, then we will end up with a
4067  * consistent fs on disk.  Record that fact.
4068  */
4069 static void ext4_mark_recovery_complete(struct super_block *sb,
4070                                         struct ext4_super_block *es)
4071 {
4072         journal_t *journal = EXT4_SB(sb)->s_journal;
4073
4074         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4075                 BUG_ON(journal != NULL);
4076                 return;
4077         }
4078         jbd2_journal_lock_updates(journal);
4079         if (jbd2_journal_flush(journal) < 0)
4080                 goto out;
4081
4082         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
4083             sb->s_flags & MS_RDONLY) {
4084                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4085                 ext4_commit_super(sb, 1);
4086         }
4087
4088 out:
4089         jbd2_journal_unlock_updates(journal);
4090 }
4091
4092 /*
4093  * If we are mounting (or read-write remounting) a filesystem whose journal
4094  * has recorded an error from a previous lifetime, move that error to the
4095  * main filesystem now.
4096  */
4097 static void ext4_clear_journal_err(struct super_block *sb,
4098                                    struct ext4_super_block *es)
4099 {
4100         journal_t *journal;
4101         int j_errno;
4102         const char *errstr;
4103
4104         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4105
4106         journal = EXT4_SB(sb)->s_journal;
4107
4108         /*
4109          * Now check for any error status which may have been recorded in the
4110          * journal by a prior ext4_error() or ext4_abort()
4111          */
4112
4113         j_errno = jbd2_journal_errno(journal);
4114         if (j_errno) {
4115                 char nbuf[16];
4116
4117                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4118                 ext4_warning(sb, "Filesystem error recorded "
4119                              "from previous mount: %s", errstr);
4120                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4121
4122                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4123                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4124                 ext4_commit_super(sb, 1);
4125
4126                 jbd2_journal_clear_err(journal);
4127         }
4128 }
4129
4130 /*
4131  * Force the running and committing transactions to commit,
4132  * and wait on the commit.
4133  */
4134 int ext4_force_commit(struct super_block *sb)
4135 {
4136         journal_t *journal;
4137         int ret = 0;
4138
4139         if (sb->s_flags & MS_RDONLY)
4140                 return 0;
4141
4142         journal = EXT4_SB(sb)->s_journal;
4143         if (journal) {
4144                 vfs_check_frozen(sb, SB_FREEZE_TRANS);
4145                 ret = ext4_journal_force_commit(journal);
4146         }
4147
4148         return ret;
4149 }
4150
4151 static void ext4_write_super(struct super_block *sb)
4152 {
4153         lock_super(sb);
4154         ext4_commit_super(sb, 1);
4155         unlock_super(sb);
4156 }
4157
4158 static int ext4_sync_fs(struct super_block *sb, int wait)
4159 {
4160         int ret = 0;
4161         tid_t target;
4162         struct ext4_sb_info *sbi = EXT4_SB(sb);
4163
4164         trace_ext4_sync_fs(sb, wait);
4165         flush_workqueue(sbi->dio_unwritten_wq);
4166         if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4167                 if (wait)
4168                         jbd2_log_wait_commit(sbi->s_journal, target);
4169         }
4170         return ret;
4171 }
4172
4173 /*
4174  * LVM calls this function before a (read-only) snapshot is created.  This
4175  * gives us a chance to flush the journal completely and mark the fs clean.
4176  *
4177  * Note that only this function cannot bring a filesystem to be in a clean
4178  * state independently, because ext4 prevents a new handle from being started
4179  * by @sb->s_frozen, which stays in an upper layer.  It thus needs help from
4180  * the upper layer.
4181  */
4182 static int ext4_freeze(struct super_block *sb)
4183 {
4184         int error = 0;
4185         journal_t *journal;
4186
4187         if (sb->s_flags & MS_RDONLY)
4188                 return 0;
4189
4190         journal = EXT4_SB(sb)->s_journal;
4191
4192         /* Now we set up the journal barrier. */
4193         jbd2_journal_lock_updates(journal);
4194
4195         /*
4196          * Don't clear the needs_recovery flag if we failed to flush
4197          * the journal.
4198          */
4199         error = jbd2_journal_flush(journal);
4200         if (error < 0)
4201                 goto out;
4202
4203         /* Journal blocked and flushed, clear needs_recovery flag. */
4204         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4205         error = ext4_commit_super(sb, 1);
4206 out:
4207         /* we rely on s_frozen to stop further updates */
4208         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4209         return error;
4210 }
4211
4212 /*
4213  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4214  * flag here, even though the filesystem is not technically dirty yet.
4215  */
4216 static int ext4_unfreeze(struct super_block *sb)
4217 {
4218         if (sb->s_flags & MS_RDONLY)
4219                 return 0;
4220
4221         lock_super(sb);
4222         /* Reset the needs_recovery flag before the fs is unlocked. */
4223         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4224         ext4_commit_super(sb, 1);
4225         unlock_super(sb);
4226         return 0;
4227 }
4228
4229 /*
4230  * Structure to save mount options for ext4_remount's benefit
4231  */
4232 struct ext4_mount_options {
4233         unsigned long s_mount_opt;
4234         unsigned long s_mount_opt2;
4235         uid_t s_resuid;
4236         gid_t s_resgid;
4237         unsigned long s_commit_interval;
4238         u32 s_min_batch_time, s_max_batch_time;
4239 #ifdef CONFIG_QUOTA
4240         int s_jquota_fmt;
4241         char *s_qf_names[MAXQUOTAS];
4242 #endif
4243 };
4244
4245 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4246 {
4247         struct ext4_super_block *es;
4248         struct ext4_sb_info *sbi = EXT4_SB(sb);
4249         ext4_fsblk_t n_blocks_count = 0;
4250         unsigned long old_sb_flags;
4251         struct ext4_mount_options old_opts;
4252         int enable_quota = 0;
4253         ext4_group_t g;
4254         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4255         int err;
4256 #ifdef CONFIG_QUOTA
4257         int i;
4258 #endif
4259         char *orig_data = kstrdup(data, GFP_KERNEL);
4260
4261         /* Store the original options */
4262         lock_super(sb);
4263         old_sb_flags = sb->s_flags;
4264         old_opts.s_mount_opt = sbi->s_mount_opt;
4265         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4266         old_opts.s_resuid = sbi->s_resuid;
4267         old_opts.s_resgid = sbi->s_resgid;
4268         old_opts.s_commit_interval = sbi->s_commit_interval;
4269         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4270         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4271 #ifdef CONFIG_QUOTA
4272         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4273         for (i = 0; i < MAXQUOTAS; i++)
4274                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
4275 #endif
4276         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4277                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4278
4279         /*
4280          * Allow the "check" option to be passed as a remount option.
4281          */
4282         if (!parse_options(data, sb, NULL, &journal_ioprio,
4283                            &n_blocks_count, 1)) {
4284                 err = -EINVAL;
4285                 goto restore_opts;
4286         }
4287
4288         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4289                 ext4_abort(sb, "Abort forced by user");
4290
4291         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
4292                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
4293
4294         es = sbi->s_es;
4295
4296         if (sbi->s_journal) {
4297                 ext4_init_journal_params(sb, sbi->s_journal);
4298                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4299         }
4300
4301         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
4302                 n_blocks_count > ext4_blocks_count(es)) {
4303                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
4304                         err = -EROFS;
4305                         goto restore_opts;
4306                 }
4307
4308                 if (*flags & MS_RDONLY) {
4309                         err = dquot_suspend(sb, -1);
4310                         if (err < 0)
4311                                 goto restore_opts;
4312
4313                         /*
4314                          * First of all, the unconditional stuff we have to do
4315                          * to disable replay of the journal when we next remount
4316                          */
4317                         sb->s_flags |= MS_RDONLY;
4318
4319                         /*
4320                          * OK, test if we are remounting a valid rw partition
4321                          * readonly, and if so set the rdonly flag and then
4322                          * mark the partition as valid again.
4323                          */
4324                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
4325                             (sbi->s_mount_state & EXT4_VALID_FS))
4326                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
4327
4328                         if (sbi->s_journal)
4329                                 ext4_mark_recovery_complete(sb, es);
4330                 } else {
4331                         /* Make sure we can mount this feature set readwrite */
4332                         if (!ext4_feature_set_ok(sb, 0)) {
4333                                 err = -EROFS;
4334                                 goto restore_opts;
4335                         }
4336                         /*
4337                          * Make sure the group descriptor checksums
4338                          * are sane.  If they aren't, refuse to remount r/w.
4339                          */
4340                         for (g = 0; g < sbi->s_groups_count; g++) {
4341                                 struct ext4_group_desc *gdp =
4342                                         ext4_get_group_desc(sb, g, NULL);
4343
4344                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
4345                                         ext4_msg(sb, KERN_ERR,
4346                "ext4_remount: Checksum for group %u failed (%u!=%u)",
4347                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
4348                                                le16_to_cpu(gdp->bg_checksum));
4349                                         err = -EINVAL;
4350                                         goto restore_opts;
4351                                 }
4352                         }
4353
4354                         /*
4355                          * If we have an unprocessed orphan list hanging
4356                          * around from a previously readonly bdev mount,
4357                          * require a full umount/remount for now.
4358                          */
4359                         if (es->s_last_orphan) {
4360                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
4361                                        "remount RDWR because of unprocessed "
4362                                        "orphan inode list.  Please "
4363                                        "umount/remount instead");
4364                                 err = -EINVAL;
4365                                 goto restore_opts;
4366                         }
4367
4368                         /*
4369                          * Mounting a RDONLY partition read-write, so reread
4370                          * and store the current valid flag.  (It may have
4371                          * been changed by e2fsck since we originally mounted
4372                          * the partition.)
4373                          */
4374                         if (sbi->s_journal)
4375                                 ext4_clear_journal_err(sb, es);
4376                         sbi->s_mount_state = le16_to_cpu(es->s_state);
4377                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
4378                                 goto restore_opts;
4379                         if (!ext4_setup_super(sb, es, 0))
4380                                 sb->s_flags &= ~MS_RDONLY;
4381                         enable_quota = 1;
4382                 }
4383         }
4384
4385         /*
4386          * Reinitialize lazy itable initialization thread based on
4387          * current settings
4388          */
4389         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
4390                 ext4_unregister_li_request(sb);
4391         else {
4392                 ext4_group_t first_not_zeroed;
4393                 first_not_zeroed = ext4_has_uninit_itable(sb);
4394                 ext4_register_li_request(sb, first_not_zeroed);
4395         }
4396
4397         ext4_setup_system_zone(sb);
4398         if (sbi->s_journal == NULL)
4399                 ext4_commit_super(sb, 1);
4400
4401 #ifdef CONFIG_QUOTA
4402         /* Release old quota file names */
4403         for (i = 0; i < MAXQUOTAS; i++)
4404                 if (old_opts.s_qf_names[i] &&
4405                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4406                         kfree(old_opts.s_qf_names[i]);
4407 #endif
4408         unlock_super(sb);
4409         if (enable_quota)
4410                 dquot_resume(sb, -1);
4411
4412         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
4413         kfree(orig_data);
4414         return 0;
4415
4416 restore_opts:
4417         sb->s_flags = old_sb_flags;
4418         sbi->s_mount_opt = old_opts.s_mount_opt;
4419         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
4420         sbi->s_resuid = old_opts.s_resuid;
4421         sbi->s_resgid = old_opts.s_resgid;
4422         sbi->s_commit_interval = old_opts.s_commit_interval;
4423         sbi->s_min_batch_time = old_opts.s_min_batch_time;
4424         sbi->s_max_batch_time = old_opts.s_max_batch_time;
4425 #ifdef CONFIG_QUOTA
4426         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
4427         for (i = 0; i < MAXQUOTAS; i++) {
4428                 if (sbi->s_qf_names[i] &&
4429                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4430                         kfree(sbi->s_qf_names[i]);
4431                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
4432         }
4433 #endif
4434         unlock_super(sb);
4435         kfree(orig_data);
4436         return err;
4437 }
4438
4439 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
4440 {
4441         struct super_block *sb = dentry->d_sb;
4442         struct ext4_sb_info *sbi = EXT4_SB(sb);
4443         struct ext4_super_block *es = sbi->s_es;
4444         u64 fsid;
4445
4446         if (test_opt(sb, MINIX_DF)) {
4447                 sbi->s_overhead_last = 0;
4448         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
4449                 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4450                 ext4_fsblk_t overhead = 0;
4451
4452                 /*
4453                  * Compute the overhead (FS structures).  This is constant
4454                  * for a given filesystem unless the number of block groups
4455                  * changes so we cache the previous value until it does.
4456                  */
4457
4458                 /*
4459                  * All of the blocks before first_data_block are
4460                  * overhead
4461                  */
4462                 overhead = le32_to_cpu(es->s_first_data_block);
4463
4464                 /*
4465                  * Add the overhead attributed to the superblock and
4466                  * block group descriptors.  If the sparse superblocks
4467                  * feature is turned on, then not all groups have this.
4468                  */
4469                 for (i = 0; i < ngroups; i++) {
4470                         overhead += ext4_bg_has_super(sb, i) +
4471                                 ext4_bg_num_gdb(sb, i);
4472                         cond_resched();
4473                 }
4474
4475                 /*
4476                  * Every block group has an inode bitmap, a block
4477                  * bitmap, and an inode table.
4478                  */
4479                 overhead += ngroups * (2 + sbi->s_itb_per_group);
4480                 sbi->s_overhead_last = overhead;
4481                 smp_wmb();
4482                 sbi->s_blocks_last = ext4_blocks_count(es);
4483         }
4484
4485         buf->f_type = EXT4_SUPER_MAGIC;
4486         buf->f_bsize = sb->s_blocksize;
4487         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
4488         buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
4489                        percpu_counter_sum_positive(&sbi->s_dirtyblocks_counter);
4490         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
4491         if (buf->f_bfree < ext4_r_blocks_count(es))
4492                 buf->f_bavail = 0;
4493         buf->f_files = le32_to_cpu(es->s_inodes_count);
4494         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
4495         buf->f_namelen = EXT4_NAME_LEN;
4496         fsid = le64_to_cpup((void *)es->s_uuid) ^
4497                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
4498         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
4499         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
4500
4501         return 0;
4502 }
4503
4504 /* Helper function for writing quotas on sync - we need to start transaction
4505  * before quota file is locked for write. Otherwise the are possible deadlocks:
4506  * Process 1                         Process 2
4507  * ext4_create()                     quota_sync()
4508  *   jbd2_journal_start()                  write_dquot()
4509  *   dquot_initialize()                         down(dqio_mutex)
4510  *     down(dqio_mutex)                    jbd2_journal_start()
4511  *
4512  */
4513
4514 #ifdef CONFIG_QUOTA
4515
4516 static inline struct inode *dquot_to_inode(struct dquot *dquot)
4517 {
4518         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
4519 }
4520
4521 static int ext4_write_dquot(struct dquot *dquot)
4522 {
4523         int ret, err;
4524         handle_t *handle;
4525         struct inode *inode;
4526
4527         inode = dquot_to_inode(dquot);
4528         handle = ext4_journal_start(inode,
4529                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
4530         if (IS_ERR(handle))
4531                 return PTR_ERR(handle);
4532         ret = dquot_commit(dquot);
4533         err = ext4_journal_stop(handle);
4534         if (!ret)
4535                 ret = err;
4536         return ret;
4537 }
4538
4539 static int ext4_acquire_dquot(struct dquot *dquot)
4540 {
4541         int ret, err;
4542         handle_t *handle;
4543
4544         handle = ext4_journal_start(dquot_to_inode(dquot),
4545                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
4546         if (IS_ERR(handle))
4547                 return PTR_ERR(handle);
4548         ret = dquot_acquire(dquot);
4549         err = ext4_journal_stop(handle);
4550         if (!ret)
4551                 ret = err;
4552         return ret;
4553 }
4554
4555 static int ext4_release_dquot(struct dquot *dquot)
4556 {
4557         int ret, err;
4558         handle_t *handle;
4559
4560         handle = ext4_journal_start(dquot_to_inode(dquot),
4561                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
4562         if (IS_ERR(handle)) {
4563                 /* Release dquot anyway to avoid endless cycle in dqput() */
4564                 dquot_release(dquot);
4565                 return PTR_ERR(handle);
4566         }
4567         ret = dquot_release(dquot);
4568         err = ext4_journal_stop(handle);
4569         if (!ret)
4570                 ret = err;
4571         return ret;
4572 }
4573
4574 static int ext4_mark_dquot_dirty(struct dquot *dquot)
4575 {
4576         /* Are we journaling quotas? */
4577         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
4578             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
4579                 dquot_mark_dquot_dirty(dquot);
4580                 return ext4_write_dquot(dquot);
4581         } else {
4582                 return dquot_mark_dquot_dirty(dquot);
4583         }
4584 }
4585
4586 static int ext4_write_info(struct super_block *sb, int type)
4587 {
4588         int ret, err;
4589         handle_t *handle;
4590
4591         /* Data block + inode block */
4592         handle = ext4_journal_start(sb->s_root->d_inode, 2);
4593         if (IS_ERR(handle))
4594                 return PTR_ERR(handle);
4595         ret = dquot_commit_info(sb, type);
4596         err = ext4_journal_stop(handle);
4597         if (!ret)
4598                 ret = err;
4599         return ret;
4600 }
4601
4602 /*
4603  * Turn on quotas during mount time - we need to find
4604  * the quota file and such...
4605  */
4606 static int ext4_quota_on_mount(struct super_block *sb, int type)
4607 {
4608         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
4609                                         EXT4_SB(sb)->s_jquota_fmt, type);
4610 }
4611
4612 /*
4613  * Standard function to be called on quota_on
4614  */
4615 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
4616                          struct path *path)
4617 {
4618         int err;
4619
4620         if (!test_opt(sb, QUOTA))
4621                 return -EINVAL;
4622
4623         /* Quotafile not on the same filesystem? */
4624         if (path->mnt->mnt_sb != sb)
4625                 return -EXDEV;
4626         /* Journaling quota? */
4627         if (EXT4_SB(sb)->s_qf_names[type]) {
4628                 /* Quotafile not in fs root? */
4629                 if (path->dentry->d_parent != sb->s_root)
4630                         ext4_msg(sb, KERN_WARNING,
4631                                 "Quota file not on filesystem root. "
4632                                 "Journaled quota will not work");
4633         }
4634
4635         /*
4636          * When we journal data on quota file, we have to flush journal to see
4637          * all updates to the file when we bypass pagecache...
4638          */
4639         if (EXT4_SB(sb)->s_journal &&
4640             ext4_should_journal_data(path->dentry->d_inode)) {
4641                 /*
4642                  * We don't need to lock updates but journal_flush() could
4643                  * otherwise be livelocked...
4644                  */
4645                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
4646                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
4647                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4648                 if (err)
4649                         return err;
4650         }
4651
4652         return dquot_quota_on(sb, type, format_id, path);
4653 }
4654
4655 static int ext4_quota_off(struct super_block *sb, int type)
4656 {
4657         struct inode *inode = sb_dqopt(sb)->files[type];
4658         handle_t *handle;
4659
4660         /* Force all delayed allocation blocks to be allocated.
4661          * Caller already holds s_umount sem */
4662         if (test_opt(sb, DELALLOC))
4663                 sync_filesystem(sb);
4664
4665         if (!inode)
4666                 goto out;
4667
4668         /* Update modification times of quota files when userspace can
4669          * start looking at them */
4670         handle = ext4_journal_start(inode, 1);
4671         if (IS_ERR(handle))
4672                 goto out;
4673         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
4674         ext4_mark_inode_dirty(handle, inode);
4675         ext4_journal_stop(handle);
4676
4677 out:
4678         return dquot_quota_off(sb, type);
4679 }
4680
4681 /* Read data from quotafile - avoid pagecache and such because we cannot afford
4682  * acquiring the locks... As quota files are never truncated and quota code
4683  * itself serializes the operations (and no one else should touch the files)
4684  * we don't have to be afraid of races */
4685 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
4686                                size_t len, loff_t off)
4687 {
4688         struct inode *inode = sb_dqopt(sb)->files[type];
4689         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4690         int err = 0;
4691         int offset = off & (sb->s_blocksize - 1);
4692         int tocopy;
4693         size_t toread;
4694         struct buffer_head *bh;
4695         loff_t i_size = i_size_read(inode);
4696
4697         if (off > i_size)
4698                 return 0;
4699         if (off+len > i_size)
4700                 len = i_size-off;
4701         toread = len;
4702         while (toread > 0) {
4703                 tocopy = sb->s_blocksize - offset < toread ?
4704                                 sb->s_blocksize - offset : toread;
4705                 bh = ext4_bread(NULL, inode, blk, 0, &err);
4706                 if (err)
4707                         return err;
4708                 if (!bh)        /* A hole? */
4709                         memset(data, 0, tocopy);
4710                 else
4711                         memcpy(data, bh->b_data+offset, tocopy);
4712                 brelse(bh);
4713                 offset = 0;
4714                 toread -= tocopy;
4715                 data += tocopy;
4716                 blk++;
4717         }
4718         return len;
4719 }
4720
4721 /* Write to quotafile (we know the transaction is already started and has
4722  * enough credits) */
4723 static ssize_t ext4_quota_write(struct super_block *sb, int type,
4724                                 const char *data, size_t len, loff_t off)
4725 {
4726         struct inode *inode = sb_dqopt(sb)->files[type];
4727         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4728         int err = 0;
4729         int offset = off & (sb->s_blocksize - 1);
4730         struct buffer_head *bh;
4731         handle_t *handle = journal_current_handle();
4732
4733         if (EXT4_SB(sb)->s_journal && !handle) {
4734                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4735                         " cancelled because transaction is not started",
4736                         (unsigned long long)off, (unsigned long long)len);
4737                 return -EIO;
4738         }
4739         /*
4740          * Since we account only one data block in transaction credits,
4741          * then it is impossible to cross a block boundary.
4742          */
4743         if (sb->s_blocksize - offset < len) {
4744                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4745                         " cancelled because not block aligned",
4746                         (unsigned long long)off, (unsigned long long)len);
4747                 return -EIO;
4748         }
4749
4750         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
4751         bh = ext4_bread(handle, inode, blk, 1, &err);
4752         if (!bh)
4753                 goto out;
4754         err = ext4_journal_get_write_access(handle, bh);
4755         if (err) {
4756                 brelse(bh);
4757                 goto out;
4758         }
4759         lock_buffer(bh);
4760         memcpy(bh->b_data+offset, data, len);
4761         flush_dcache_page(bh->b_page);
4762         unlock_buffer(bh);
4763         err = ext4_handle_dirty_metadata(handle, NULL, bh);
4764         brelse(bh);
4765 out:
4766         if (err) {
4767                 mutex_unlock(&inode->i_mutex);
4768                 return err;
4769         }
4770         if (inode->i_size < off + len) {
4771                 i_size_write(inode, off + len);
4772                 EXT4_I(inode)->i_disksize = inode->i_size;
4773                 ext4_mark_inode_dirty(handle, inode);
4774         }
4775         mutex_unlock(&inode->i_mutex);
4776         return len;
4777 }
4778
4779 #endif
4780
4781 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
4782                        const char *dev_name, void *data)
4783 {
4784         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
4785 }
4786
4787 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4788 static inline void register_as_ext2(void)
4789 {
4790         int err = register_filesystem(&ext2_fs_type);
4791         if (err)
4792                 printk(KERN_WARNING
4793                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
4794 }
4795
4796 static inline void unregister_as_ext2(void)
4797 {
4798         unregister_filesystem(&ext2_fs_type);
4799 }
4800
4801 static inline int ext2_feature_set_ok(struct super_block *sb)
4802 {
4803         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))
4804                 return 0;
4805         if (sb->s_flags & MS_RDONLY)
4806                 return 1;
4807         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))
4808                 return 0;
4809         return 1;
4810 }
4811 MODULE_ALIAS("ext2");
4812 #else
4813 static inline void register_as_ext2(void) { }
4814 static inline void unregister_as_ext2(void) { }
4815 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
4816 #endif
4817
4818 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4819 static inline void register_as_ext3(void)
4820 {
4821         int err = register_filesystem(&ext3_fs_type);
4822         if (err)
4823                 printk(KERN_WARNING
4824                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
4825 }
4826
4827 static inline void unregister_as_ext3(void)
4828 {
4829         unregister_filesystem(&ext3_fs_type);
4830 }
4831
4832 static inline int ext3_feature_set_ok(struct super_block *sb)
4833 {
4834         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT3_FEATURE_INCOMPAT_SUPP))
4835                 return 0;
4836         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
4837                 return 0;
4838         if (sb->s_flags & MS_RDONLY)
4839                 return 1;
4840         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT3_FEATURE_RO_COMPAT_SUPP))
4841                 return 0;
4842         return 1;
4843 }
4844 MODULE_ALIAS("ext3");
4845 #else
4846 static inline void register_as_ext3(void) { }
4847 static inline void unregister_as_ext3(void) { }
4848 static inline int ext3_feature_set_ok(struct super_block *sb) { return 0; }
4849 #endif
4850
4851 static struct file_system_type ext4_fs_type = {
4852         .owner          = THIS_MODULE,
4853         .name           = "ext4",
4854         .mount          = ext4_mount,
4855         .kill_sb        = kill_block_super,
4856         .fs_flags       = FS_REQUIRES_DEV,
4857 };
4858
4859 static int __init ext4_init_feat_adverts(void)
4860 {
4861         struct ext4_features *ef;
4862         int ret = -ENOMEM;
4863
4864         ef = kzalloc(sizeof(struct ext4_features), GFP_KERNEL);
4865         if (!ef)
4866                 goto out;
4867
4868         ef->f_kobj.kset = ext4_kset;
4869         init_completion(&ef->f_kobj_unregister);
4870         ret = kobject_init_and_add(&ef->f_kobj, &ext4_feat_ktype, NULL,
4871                                    "features");
4872         if (ret) {
4873                 kfree(ef);
4874                 goto out;
4875         }
4876
4877         ext4_feat = ef;
4878         ret = 0;
4879 out:
4880         return ret;
4881 }
4882
4883 static void ext4_exit_feat_adverts(void)
4884 {
4885         kobject_put(&ext4_feat->f_kobj);
4886         wait_for_completion(&ext4_feat->f_kobj_unregister);
4887         kfree(ext4_feat);
4888 }
4889
4890 /* Shared across all ext4 file systems */
4891 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
4892 struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
4893
4894 static int __init ext4_init_fs(void)
4895 {
4896         int i, err;
4897
4898         ext4_check_flag_values();
4899
4900         for (i = 0; i < EXT4_WQ_HASH_SZ; i++) {
4901                 mutex_init(&ext4__aio_mutex[i]);
4902                 init_waitqueue_head(&ext4__ioend_wq[i]);
4903         }
4904
4905         err = ext4_init_pageio();
4906         if (err)
4907                 return err;
4908         err = ext4_init_system_zone();
4909         if (err)
4910                 goto out7;
4911         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
4912         if (!ext4_kset)
4913                 goto out6;
4914         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
4915         if (!ext4_proc_root)
4916                 goto out5;
4917
4918         err = ext4_init_feat_adverts();
4919         if (err)
4920                 goto out4;
4921
4922         err = ext4_init_mballoc();
4923         if (err)
4924                 goto out3;
4925
4926         err = ext4_init_xattr();
4927         if (err)
4928                 goto out2;
4929         err = init_inodecache();
4930         if (err)
4931                 goto out1;
4932         register_as_ext3();
4933         register_as_ext2();
4934         err = register_filesystem(&ext4_fs_type);
4935         if (err)
4936                 goto out;
4937
4938         ext4_li_info = NULL;
4939         mutex_init(&ext4_li_mtx);
4940         return 0;
4941 out:
4942         unregister_as_ext2();
4943         unregister_as_ext3();
4944         destroy_inodecache();
4945 out1:
4946         ext4_exit_xattr();
4947 out2:
4948         ext4_exit_mballoc();
4949 out3:
4950         ext4_exit_feat_adverts();
4951 out4:
4952         remove_proc_entry("fs/ext4", NULL);
4953 out5:
4954         kset_unregister(ext4_kset);
4955 out6:
4956         ext4_exit_system_zone();
4957 out7:
4958         ext4_exit_pageio();
4959         return err;
4960 }
4961
4962 static void __exit ext4_exit_fs(void)
4963 {
4964         ext4_destroy_lazyinit_thread();
4965         unregister_as_ext2();
4966         unregister_as_ext3();
4967         unregister_filesystem(&ext4_fs_type);
4968         destroy_inodecache();
4969         ext4_exit_xattr();
4970         ext4_exit_mballoc();
4971         ext4_exit_feat_adverts();
4972         remove_proc_entry("fs/ext4", NULL);
4973         kset_unregister(ext4_kset);
4974         ext4_exit_system_zone();
4975         ext4_exit_pageio();
4976 }
4977
4978 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
4979 MODULE_DESCRIPTION("Fourth Extended Filesystem");
4980 MODULE_LICENSE("GPL");
4981 module_init(ext4_init_fs)
4982 module_exit(ext4_exit_fs)