fs/ext4/ioctl.c

   1 /*
   2  * linux/fs/ext4/ioctl.c
   3  *
   4  * Copyright (C) 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
  10 #include <linux/fs.h>
  11 #include <linux/jbd2.h>
  12 #include <linux/capability.h>
  13 #include <linux/time.h>
  14 #include <linux/compat.h>
  15 #include <linux/mount.h>
  16 #include <linux/file.h>
  17 #include <asm/uaccess.h>
  18 #include "ext4_jbd2.h"
  19 #include "ext4.h"
  20
  21 #define MAX_32_NUM ((((unsigned long long) 1) << 32) - 1)
  22
  23 /**
  24  * Swap memory between @a and @b for @len bytes.
  25  *
  26  * @a:          pointer to first memory area
  27  * @b:          pointer to second memory area
  28  * @len:        number of bytes to swap
  29  *
  30  */
  31 static void memswap(void *a, void *b, size_t len)
  32 {
  33         unsigned char *ap, *bp;
  34         unsigned char tmp;
  35
  36         ap = (unsigned char *)a;
  37         bp = (unsigned char *)b;
  38         while (len-- > 0) {
  39                 tmp = *ap;
  40                 *ap = *bp;
  41                 *bp = tmp;
  42                 ap++;
  43                 bp++;
  44         }
  45 }
  46
  47 /**
  48  * Swap i_data and associated attributes between @inode1 and @inode2.
  49  * This function is used for the primary swap between inode1 and inode2
  50  * and also to revert this primary swap in case of errors.
  51  *
  52  * Therefore you have to make sure, that calling this method twice
  53  * will revert all changes.
  54  *
  55  * @inode1:     pointer to first inode
  56  * @inode2:     pointer to second inode
  57  */
  58 static void swap_inode_data(struct inode *inode1, struct inode *inode2)
  59 {
  60         loff_t isize;
  61         struct ext4_inode_info *ei1;
  62         struct ext4_inode_info *ei2;
  63
  64         ei1 = EXT4_I(inode1);
  65         ei2 = EXT4_I(inode2);
  66
  67         memswap(&inode1->i_flags, &inode2->i_flags, sizeof(inode1->i_flags));
  68         memswap(&inode1->i_version, &inode2->i_version,
  69                   sizeof(inode1->i_version));
  70         memswap(&inode1->i_blocks, &inode2->i_blocks,
  71                   sizeof(inode1->i_blocks));
  72         memswap(&inode1->i_bytes, &inode2->i_bytes, sizeof(inode1->i_bytes));
  73         memswap(&inode1->i_atime, &inode2->i_atime, sizeof(inode1->i_atime));
  74         memswap(&inode1->i_mtime, &inode2->i_mtime, sizeof(inode1->i_mtime));
  75
  76         memswap(ei1->i_data, ei2->i_data, sizeof(ei1->i_data));
  77         memswap(&ei1->i_flags, &ei2->i_flags, sizeof(ei1->i_flags));
  78         memswap(&ei1->i_disksize, &ei2->i_disksize, sizeof(ei1->i_disksize));
  79         ext4_es_remove_extent(inode1, 0, EXT_MAX_BLOCKS);
  80         ext4_es_remove_extent(inode2, 0, EXT_MAX_BLOCKS);
  81         ext4_es_lru_del(inode1);
  82         ext4_es_lru_del(inode2);
  83
  84         isize = i_size_read(inode1);
  85         i_size_write(inode1, i_size_read(inode2));
  86         i_size_write(inode2, isize);
  87 }
  88
  89 /**
  90  * Swap the information from the given @inode and the inode
  91  * EXT4_BOOT_LOADER_INO. It will basically swap i_data and all other
  92  * important fields of the inodes.
  93  *
  94  * @sb:         the super block of the filesystem
  95  * @inode:      the inode to swap with EXT4_BOOT_LOADER_INO
  96  *
  97  */
  98 static long swap_inode_boot_loader(struct super_block *sb,
  99                                 struct inode *inode)
 100 {
 101         handle_t *handle;
 102         int err;
 103         struct inode *inode_bl;
 104         struct ext4_inode_info *ei_bl;
 105         struct ext4_sb_info *sbi = EXT4_SB(sb);
 106
 107         if (inode->i_nlink != 1 || !S_ISREG(inode->i_mode)) {
 108                 err = -EINVAL;
 109                 goto swap_boot_out;
 110         }
 111
 112         if (!inode_owner_or_capable(inode) || !capable(CAP_SYS_ADMIN)) {
 113                 err = -EPERM;
 114                 goto swap_boot_out;
 115         }
 116
 117         inode_bl = ext4_iget(sb, EXT4_BOOT_LOADER_INO);
 118         if (IS_ERR(inode_bl)) {
 119                 err = PTR_ERR(inode_bl);
 120                 goto swap_boot_out;
 121         }
 122         ei_bl = EXT4_I(inode_bl);
 123
 124         filemap_flush(inode->i_mapping);
 125         filemap_flush(inode_bl->i_mapping);
 126
 127         /* Protect orig inodes against a truncate and make sure,
 128          * that only 1 swap_inode_boot_loader is running. */
 129         lock_two_nondirectories(inode, inode_bl);
 130
 131         truncate_inode_pages(&inode->i_data, 0);
 132         truncate_inode_pages(&inode_bl->i_data, 0);
 133
 134         /* Wait for all existing dio workers */
 135         ext4_inode_block_unlocked_dio(inode);
 136         ext4_inode_block_unlocked_dio(inode_bl);
 137         inode_dio_wait(inode);
 138         inode_dio_wait(inode_bl);
 139
 140         handle = ext4_journal_start(inode_bl, EXT4_HT_MOVE_EXTENTS, 2);
 141         if (IS_ERR(handle)) {
 142                 err = -EINVAL;
 143                 goto journal_err_out;
 144         }
 145
 146         /* Protect extent tree against block allocations via delalloc */
 147         ext4_double_down_write_data_sem(inode, inode_bl);
 148
 149         if (inode_bl->i_nlink == 0) {
 150                 /* this inode has never been used as a BOOT_LOADER */
 151                 set_nlink(inode_bl, 1);
 152                 i_uid_write(inode_bl, 0);
 153                 i_gid_write(inode_bl, 0);
 154                 inode_bl->i_flags = 0;
 155                 ei_bl->i_flags = 0;
 156                 inode_bl->i_version = 1;
 157                 i_size_write(inode_bl, 0);
 158                 inode_bl->i_mode = S_IFREG;
 159                 if (EXT4_HAS_INCOMPAT_FEATURE(sb,
 160                                               EXT4_FEATURE_INCOMPAT_EXTENTS)) {
 161                         ext4_set_inode_flag(inode_bl, EXT4_INODE_EXTENTS);
 162                         ext4_ext_tree_init(handle, inode_bl);
 163                 } else
 164                         memset(ei_bl->i_data, 0, sizeof(ei_bl->i_data));
 165         }
 166
 167         swap_inode_data(inode, inode_bl);
 168
 169         inode->i_ctime = inode_bl->i_ctime = ext4_current_time(inode);
 170
 171         spin_lock(&sbi->s_next_gen_lock);
 172         inode->i_generation = sbi->s_next_generation++;
 173         inode_bl->i_generation = sbi->s_next_generation++;
 174         spin_unlock(&sbi->s_next_gen_lock);
 175
 176         ext4_discard_preallocations(inode);
 177
 178         err = ext4_mark_inode_dirty(handle, inode);
 179         if (err < 0) {
 180                 ext4_warning(inode->i_sb,
 181                         "couldn't mark inode #%lu dirty (err %d)",
 182                         inode->i_ino, err);
 183                 /* Revert all changes: */
 184                 swap_inode_data(inode, inode_bl);
 185         } else {
 186                 err = ext4_mark_inode_dirty(handle, inode_bl);
 187                 if (err < 0) {
 188                         ext4_warning(inode_bl->i_sb,
 189                                 "couldn't mark inode #%lu dirty (err %d)",
 190                                 inode_bl->i_ino, err);
 191                         /* Revert all changes: */
 192                         swap_inode_data(inode, inode_bl);
 193                         ext4_mark_inode_dirty(handle, inode);
 194                 }
 195         }
 196
 197         ext4_journal_stop(handle);
 198
 199         ext4_double_up_write_data_sem(inode, inode_bl);
 200
 201 journal_err_out:
 202         ext4_inode_resume_unlocked_dio(inode);
 203         ext4_inode_resume_unlocked_dio(inode_bl);
 204
 205         unlock_two_nondirectories(inode, inode_bl);
 206
 207         iput(inode_bl);
 208
 209 swap_boot_out:
 210         return err;
 211 }
 212
 213 long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 214 {
 215         struct inode *inode = file_inode(filp);
 216         struct super_block *sb = inode->i_sb;
 217         struct ext4_inode_info *ei = EXT4_I(inode);
 218         unsigned int flags;
 219
 220         ext4_debug("cmd = %u, arg = %lu\n", cmd, arg);
 221
 222         switch (cmd) {
 223         case EXT4_IOC_GETFLAGS:
 224                 ext4_get_inode_flags(ei);
 225                 flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
 226                 return put_user(flags, (int __user *) arg);
 227         case EXT4_IOC_SETFLAGS: {
 228                 handle_t *handle = NULL;
 229                 int err, migrate = 0;
 230                 struct ext4_iloc iloc;
 231                 unsigned int oldflags, mask, i;
 232                 unsigned int jflag;
 233
 234                 if (!inode_owner_or_capable(inode))
 235                         return -EACCES;
 236
 237                 if (get_user(flags, (int __user *) arg))
 238                         return -EFAULT;
 239
 240                 err = mnt_want_write_file(filp);
 241                 if (err)
 242                         return err;
 243
 244                 flags = ext4_mask_flags(inode->i_mode, flags);
 245
 246                 err = -EPERM;
 247                 mutex_lock(&inode->i_mutex);
 248                 /* Is it quota file? Do not allow user to mess with it */
 249                 if (IS_NOQUOTA(inode))
 250                         goto flags_out;
 251
 252                 oldflags = ei->i_flags;
 253
 254                 /* The JOURNAL_DATA flag is modifiable only by root */
 255                 jflag = flags & EXT4_JOURNAL_DATA_FL;
 256
 257                 /*
 258                  * The IMMUTABLE and APPEND_ONLY flags can only be changed by
 259                  * the relevant capability.
 260                  *
 261                  * This test looks nicer. Thanks to Pauline Middelink
 262                  */
 263                 if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) {
 264                         if (!capable(CAP_LINUX_IMMUTABLE))
 265                                 goto flags_out;
 266                 }
 267
 268                 /*
 269                  * The JOURNAL_DATA flag can only be changed by
 270                  * the relevant capability.
 271                  */
 272                 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) {
 273                         if (!capable(CAP_SYS_RESOURCE))
 274                                 goto flags_out;
 275                 }
 276                 if ((flags ^ oldflags) & EXT4_EXTENTS_FL)
 277                         migrate = 1;
 278
 279                 if (flags & EXT4_EOFBLOCKS_FL) {
 280                         /* we don't support adding EOFBLOCKS flag */
 281                         if (!(oldflags & EXT4_EOFBLOCKS_FL)) {
 282                                 err = -EOPNOTSUPP;
 283                                 goto flags_out;
 284                         }
 285                 } else if (oldflags & EXT4_EOFBLOCKS_FL)
 286                         ext4_truncate(inode);
 287
 288                 handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
 289                 if (IS_ERR(handle)) {
 290                         err = PTR_ERR(handle);
 291                         goto flags_out;
 292                 }
 293                 if (IS_SYNC(inode))
 294                         ext4_handle_sync(handle);
 295                 err = ext4_reserve_inode_write(handle, inode, &iloc);
 296                 if (err)
 297                         goto flags_err;
 298
 299                 for (i = 0, mask = 1; i < 32; i++, mask <<= 1) {
 300                         if (!(mask & EXT4_FL_USER_MODIFIABLE))
 301                                 continue;
 302                         if (mask & flags)
 303                                 ext4_set_inode_flag(inode, i);
 304                         else
 305                                 ext4_clear_inode_flag(inode, i);
 306                 }
 307
 308                 ext4_set_inode_flags(inode);
 309                 inode->i_ctime = ext4_current_time(inode);
 310
 311                 err = ext4_mark_iloc_dirty(handle, inode, &iloc);
 312 flags_err:
 313                 ext4_journal_stop(handle);
 314                 if (err)
 315                         goto flags_out;
 316
 317                 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
 318                         err = ext4_change_inode_journal_flag(inode, jflag);
 319                 if (err)
 320                         goto flags_out;
 321                 if (migrate) {
 322                         if (flags & EXT4_EXTENTS_FL)
 323                                 err = ext4_ext_migrate(inode);
 324                         else
 325                                 err = ext4_ind_migrate(inode);
 326                 }
 327
 328 flags_out:
 329                 mutex_unlock(&inode->i_mutex);
 330                 mnt_drop_write_file(filp);
 331                 return err;
 332         }
 333         case EXT4_IOC_GETVERSION:
 334         case EXT4_IOC_GETVERSION_OLD:
 335                 return put_user(inode->i_generation, (int __user *) arg);
 336         case EXT4_IOC_SETVERSION:
 337         case EXT4_IOC_SETVERSION_OLD: {
 338                 handle_t *handle;
 339                 struct ext4_iloc iloc;
 340                 __u32 generation;
 341                 int err;
 342
 343                 if (!inode_owner_or_capable(inode))
 344                         return -EPERM;
 345
 346                 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
 347                                 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
 348                         ext4_warning(sb, "Setting inode version is not "
 349                                      "supported with metadata_csum enabled.");
 350                         return -ENOTTY;
 351                 }
 352
 353                 err = mnt_want_write_file(filp);
 354                 if (err)
 355                         return err;
 356                 if (get_user(generation, (int __user *) arg)) {
 357                         err = -EFAULT;
 358                         goto setversion_out;
 359                 }
 360
 361                 mutex_lock(&inode->i_mutex);
 362                 handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
 363                 if (IS_ERR(handle)) {
 364                         err = PTR_ERR(handle);
 365                         goto unlock_out;
 366                 }
 367                 err = ext4_reserve_inode_write(handle, inode, &iloc);
 368                 if (err == 0) {
 369                         inode->i_ctime = ext4_current_time(inode);
 370                         inode->i_generation = generation;
 371                         err = ext4_mark_iloc_dirty(handle, inode, &iloc);
 372                 }
 373                 ext4_journal_stop(handle);
 374
 375 unlock_out:
 376                 mutex_unlock(&inode->i_mutex);
 377 setversion_out:
 378                 mnt_drop_write_file(filp);
 379                 return err;
 380         }
 381         case EXT4_IOC_GROUP_EXTEND: {
 382                 ext4_fsblk_t n_blocks_count;
 383                 int err, err2=0;
 384
 385                 err = ext4_resize_begin(sb);
 386                 if (err)
 387                         return err;
 388
 389                 if (get_user(n_blocks_count, (__u32 __user *)arg)) {
 390                         err = -EFAULT;
 391                         goto group_extend_out;
 392                 }
 393
 394                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 395                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 396                         ext4_msg(sb, KERN_ERR,
 397                                  "Online resizing not supported with bigalloc");
 398                         err = -EOPNOTSUPP;
 399                         goto group_extend_out;
 400                 }
 401
 402                 err = mnt_want_write_file(filp);
 403                 if (err)
 404                         goto group_extend_out;
 405
 406                 err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
 407                 if (EXT4_SB(sb)->s_journal) {
 408                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 409                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 410                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 411                 }
 412                 if (err == 0)
 413                         err = err2;
 414                 mnt_drop_write_file(filp);
 415 group_extend_out:
 416                 ext4_resize_end(sb);
 417                 return err;
 418         }
 419
 420         case EXT4_IOC_MOVE_EXT: {
 421                 struct move_extent me;
 422                 struct fd donor;
 423                 int err;
 424
 425                 if (!(filp->f_mode & FMODE_READ) ||
 426                     !(filp->f_mode & FMODE_WRITE))
 427                         return -EBADF;
 428
 429                 if (copy_from_user(&me,
 430                         (struct move_extent __user *)arg, sizeof(me)))
 431                         return -EFAULT;
 432                 me.moved_len = 0;
 433
 434                 donor = fdget(me.donor_fd);
 435                 if (!donor.file)
 436                         return -EBADF;
 437
 438                 if (!(donor.file->f_mode & FMODE_WRITE)) {
 439                         err = -EBADF;
 440                         goto mext_out;
 441                 }
 442
 443                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 444                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 445                         ext4_msg(sb, KERN_ERR,
 446                                  "Online defrag not supported with bigalloc");
 447                         err = -EOPNOTSUPP;
 448                         goto mext_out;
 449                 }
 450
 451                 err = mnt_want_write_file(filp);
 452                 if (err)
 453                         goto mext_out;
 454
 455                 err = ext4_move_extents(filp, donor.file, me.orig_start,
 456                                         me.donor_start, me.len, &me.moved_len);
 457                 mnt_drop_write_file(filp);
 458
 459                 if (copy_to_user((struct move_extent __user *)arg,
 460                                  &me, sizeof(me)))
 461                         err = -EFAULT;
 462 mext_out:
 463                 fdput(donor);
 464                 return err;
 465         }
 466
 467         case EXT4_IOC_GROUP_ADD: {
 468                 struct ext4_new_group_data input;
 469                 int err, err2=0;
 470
 471                 err = ext4_resize_begin(sb);
 472                 if (err)
 473                         return err;
 474
 475                 if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,
 476                                 sizeof(input))) {
 477                         err = -EFAULT;
 478                         goto group_add_out;
 479                 }
 480
 481                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 482                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 483                         ext4_msg(sb, KERN_ERR,
 484                                  "Online resizing not supported with bigalloc");
 485                         err = -EOPNOTSUPP;
 486                         goto group_add_out;
 487                 }
 488
 489                 err = mnt_want_write_file(filp);
 490                 if (err)
 491                         goto group_add_out;
 492
 493                 err = ext4_group_add(sb, &input);
 494                 if (EXT4_SB(sb)->s_journal) {
 495                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 496                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 497                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 498                 }
 499                 if (err == 0)
 500                         err = err2;
 501                 mnt_drop_write_file(filp);
 502                 if (!err && ext4_has_group_desc_csum(sb) &&
 503                     test_opt(sb, INIT_INODE_TABLE))
 504                         err = ext4_register_li_request(sb, input.group);
 505 group_add_out:
 506                 ext4_resize_end(sb);
 507                 return err;
 508         }
 509
 510         case EXT4_IOC_MIGRATE:
 511         {
 512                 int err;
 513                 if (!inode_owner_or_capable(inode))
 514                         return -EACCES;
 515
 516                 err = mnt_want_write_file(filp);
 517                 if (err)
 518                         return err;
 519                 /*
 520                  * inode_mutex prevent write and truncate on the file.
 521                  * Read still goes through. We take i_data_sem in
 522                  * ext4_ext_swap_inode_data before we switch the
 523                  * inode format to prevent read.
 524                  */
 525                 mutex_lock(&(inode->i_mutex));
 526                 err = ext4_ext_migrate(inode);
 527                 mutex_unlock(&(inode->i_mutex));
 528                 mnt_drop_write_file(filp);
 529                 return err;
 530         }
 531
 532         case EXT4_IOC_ALLOC_DA_BLKS:
 533         {
 534                 int err;
 535                 if (!inode_owner_or_capable(inode))
 536                         return -EACCES;
 537
 538                 err = mnt_want_write_file(filp);
 539                 if (err)
 540                         return err;
 541                 err = ext4_alloc_da_blocks(inode);
 542                 mnt_drop_write_file(filp);
 543                 return err;
 544         }
 545
 546         case EXT4_IOC_SWAP_BOOT:
 547                 if (!(filp->f_mode & FMODE_WRITE))
 548                         return -EBADF;
 549                 return swap_inode_boot_loader(sb, inode);
 550
 551         case EXT4_IOC_RESIZE_FS: {
 552                 ext4_fsblk_t n_blocks_count;
 553                 int err = 0, err2 = 0;
 554                 ext4_group_t o_group = EXT4_SB(sb)->s_groups_count;
 555
 556                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 557                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 558                         ext4_msg(sb, KERN_ERR,
 559                                  "Online resizing not (yet) supported with bigalloc");
 560                         return -EOPNOTSUPP;
 561                 }
 562
 563                 if (copy_from_user(&n_blocks_count, (__u64 __user *)arg,
 564                                    sizeof(__u64))) {
 565                         return -EFAULT;
 566                 }
 567
 568                 err = ext4_resize_begin(sb);
 569                 if (err)
 570                         return err;
 571
 572                 err = mnt_want_write_file(filp);
 573                 if (err)
 574                         goto resizefs_out;
 575
 576                 err = ext4_resize_fs(sb, n_blocks_count);
 577                 if (EXT4_SB(sb)->s_journal) {
 578                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 579                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 580                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 581                 }
 582                 if (err == 0)
 583                         err = err2;
 584                 mnt_drop_write_file(filp);
 585                 if (!err && (o_group > EXT4_SB(sb)->s_groups_count) &&
 586                     ext4_has_group_desc_csum(sb) &&
 587                     test_opt(sb, INIT_INODE_TABLE))
 588                         err = ext4_register_li_request(sb, o_group);
 589
 590 resizefs_out:
 591                 ext4_resize_end(sb);
 592                 return err;
 593         }
 594
 595         case FITRIM:
 596         {
 597                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
 598                 struct fstrim_range range;
 599                 int ret = 0;
 600
 601                 if (!capable(CAP_SYS_ADMIN))
 602                         return -EPERM;
 603
 604                 if (!blk_queue_discard(q))
 605                         return -EOPNOTSUPP;
 606
 607                 if (copy_from_user(&range, (struct fstrim_range __user *)arg,
 608                     sizeof(range)))
 609                         return -EFAULT;
 610
 611                 range.minlen = max((unsigned int)range.minlen,
 612                                    q->limits.discard_granularity);
 613                 ret = ext4_trim_fs(sb, &range);
 614                 if (ret < 0)
 615                         return ret;
 616
 617                 if (copy_to_user((struct fstrim_range __user *)arg, &range,
 618                     sizeof(range)))
 619                         return -EFAULT;
 620
 621                 return 0;
 622         }
 623         case EXT4_IOC_PRECACHE_EXTENTS:
 624                 return ext4_ext_precache(inode);
 625
 626         default:
 627                 return -ENOTTY;
 628         }
 629 }
 630
 631 #ifdef CONFIG_COMPAT
 632 long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 633 {
 634         /* These are just misnamed, they actually get/put from/to user an int */
 635         switch (cmd) {
 636         case EXT4_IOC32_GETFLAGS:
 637                 cmd = EXT4_IOC_GETFLAGS;
 638                 break;
 639         case EXT4_IOC32_SETFLAGS:
 640                 cmd = EXT4_IOC_SETFLAGS;
 641                 break;
 642         case EXT4_IOC32_GETVERSION:
 643                 cmd = EXT4_IOC_GETVERSION;
 644                 break;
 645         case EXT4_IOC32_SETVERSION:
 646                 cmd = EXT4_IOC_SETVERSION;
 647                 break;
 648         case EXT4_IOC32_GROUP_EXTEND:
 649                 cmd = EXT4_IOC_GROUP_EXTEND;
 650                 break;
 651         case EXT4_IOC32_GETVERSION_OLD:
 652                 cmd = EXT4_IOC_GETVERSION_OLD;
 653                 break;
 654         case EXT4_IOC32_SETVERSION_OLD:
 655                 cmd = EXT4_IOC_SETVERSION_OLD;
 656                 break;
 657         case EXT4_IOC32_GETRSVSZ:
 658                 cmd = EXT4_IOC_GETRSVSZ;
 659                 break;
 660         case EXT4_IOC32_SETRSVSZ:
 661                 cmd = EXT4_IOC_SETRSVSZ;
 662                 break;
 663         case EXT4_IOC32_GROUP_ADD: {
 664                 struct compat_ext4_new_group_input __user *uinput;
 665                 struct ext4_new_group_input input;
 666                 mm_segment_t old_fs;
 667                 int err;
 668
 669                 uinput = compat_ptr(arg);
 670                 err = get_user(input.group, &uinput->group);
 671                 err |= get_user(input.block_bitmap, &uinput->block_bitmap);
 672                 err |= get_user(input.inode_bitmap, &uinput->inode_bitmap);
 673                 err |= get_user(input.inode_table, &uinput->inode_table);
 674                 err |= get_user(input.blocks_count, &uinput->blocks_count);
 675                 err |= get_user(input.reserved_blocks,
 676                                 &uinput->reserved_blocks);
 677                 if (err)
 678                         return -EFAULT;
 679                 old_fs = get_fs();
 680                 set_fs(KERNEL_DS);
 681                 err = ext4_ioctl(file, EXT4_IOC_GROUP_ADD,
 682                                  (unsigned long) &input);
 683                 set_fs(old_fs);
 684                 return err;
 685         }
 686         case EXT4_IOC_MOVE_EXT:
 687         case FITRIM:
 688         case EXT4_IOC_RESIZE_FS:
 689         case EXT4_IOC_PRECACHE_EXTENTS:
 690                 break;
 691         default:
 692                 return -ENOIOCTLCMD;
 693         }
 694         return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
 695 }
 696 #endif