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 #include "ext4_extents.h"
  21
  22 #define MAX_32_NUM ((((unsigned long long) 1) << 32) - 1)
  23
  24 /**
  25  * Swap memory between @a and @b for @len bytes.
  26  *
  27  * @a:          pointer to first memory area
  28  * @b:          pointer to second memory area
  29  * @len:        number of bytes to swap
  30  *
  31  */
  32 static void memswap(void *a, void *b, size_t len)
  33 {
  34         unsigned char *ap, *bp;
  35         unsigned char tmp;
  36
  37         ap = (unsigned char *)a;
  38         bp = (unsigned char *)b;
  39         while (len-- > 0) {
  40                 tmp = *ap;
  41                 *ap = *bp;
  42                 *bp = tmp;
  43                 ap++;
  44                 bp++;
  45         }
  46 }
  47
  48 /**
  49  * Swap i_data and associated attributes between @inode1 and @inode2.
  50  * This function is used for the primary swap between inode1 and inode2
  51  * and also to revert this primary swap in case of errors.
  52  *
  53  * Therefore you have to make sure, that calling this method twice
  54  * will revert all changes.
  55  *
  56  * @inode1:     pointer to first inode
  57  * @inode2:     pointer to second inode
  58  */
  59 static void swap_inode_data(struct inode *inode1, struct inode *inode2)
  60 {
  61         loff_t isize;
  62         struct ext4_inode_info *ei1;
  63         struct ext4_inode_info *ei2;
  64
  65         ei1 = EXT4_I(inode1);
  66         ei2 = EXT4_I(inode2);
  67
  68         memswap(&inode1->i_flags, &inode2->i_flags, sizeof(inode1->i_flags));
  69         memswap(&inode1->i_version, &inode2->i_version,
  70                   sizeof(inode1->i_version));
  71         memswap(&inode1->i_blocks, &inode2->i_blocks,
  72                   sizeof(inode1->i_blocks));
  73         memswap(&inode1->i_bytes, &inode2->i_bytes, sizeof(inode1->i_bytes));
  74         memswap(&inode1->i_atime, &inode2->i_atime, sizeof(inode1->i_atime));
  75         memswap(&inode1->i_mtime, &inode2->i_mtime, sizeof(inode1->i_mtime));
  76
  77         memswap(ei1->i_data, ei2->i_data, sizeof(ei1->i_data));
  78         memswap(&ei1->i_flags, &ei2->i_flags, sizeof(ei1->i_flags));
  79         memswap(&ei1->i_disksize, &ei2->i_disksize, sizeof(ei1->i_disksize));
  80         ext4_es_remove_extent(inode1, 0, EXT_MAX_BLOCKS);
  81         ext4_es_remove_extent(inode2, 0, EXT_MAX_BLOCKS);
  82         ext4_es_lru_del(inode1);
  83         ext4_es_lru_del(inode2);
  84
  85         isize = i_size_read(inode1);
  86         i_size_write(inode1, i_size_read(inode2));
  87         i_size_write(inode2, isize);
  88 }
  89
  90 /**
  91  * Swap the information from the given @inode and the inode
  92  * EXT4_BOOT_LOADER_INO. It will basically swap i_data and all other
  93  * important fields of the inodes.
  94  *
  95  * @sb:         the super block of the filesystem
  96  * @inode:      the inode to swap with EXT4_BOOT_LOADER_INO
  97  *
  98  */
  99 static long swap_inode_boot_loader(struct super_block *sb,
 100                                 struct inode *inode)
 101 {
 102         handle_t *handle;
 103         int err;
 104         struct inode *inode_bl;
 105         struct ext4_inode_info *ei;
 106         struct ext4_inode_info *ei_bl;
 107         struct ext4_sb_info *sbi;
 108
 109         if (inode->i_nlink != 1 || !S_ISREG(inode->i_mode)) {
 110                 err = -EINVAL;
 111                 goto swap_boot_out;
 112         }
 113
 114         if (!inode_owner_or_capable(inode) || !capable(CAP_SYS_ADMIN)) {
 115                 err = -EPERM;
 116                 goto swap_boot_out;
 117         }
 118
 119         sbi = EXT4_SB(sb);
 120         ei = EXT4_I(inode);
 121
 122         inode_bl = ext4_iget(sb, EXT4_BOOT_LOADER_INO);
 123         if (IS_ERR(inode_bl)) {
 124                 err = PTR_ERR(inode_bl);
 125                 goto swap_boot_out;
 126         }
 127         ei_bl = EXT4_I(inode_bl);
 128
 129         filemap_flush(inode->i_mapping);
 130         filemap_flush(inode_bl->i_mapping);
 131
 132         /* Protect orig inodes against a truncate and make sure,
 133          * that only 1 swap_inode_boot_loader is running. */
 134         ext4_inode_double_lock(inode, inode_bl);
 135
 136         truncate_inode_pages(&inode->i_data, 0);
 137         truncate_inode_pages(&inode_bl->i_data, 0);
 138
 139         /* Wait for all existing dio workers */
 140         ext4_inode_block_unlocked_dio(inode);
 141         ext4_inode_block_unlocked_dio(inode_bl);
 142         inode_dio_wait(inode);
 143         inode_dio_wait(inode_bl);
 144
 145         handle = ext4_journal_start(inode_bl, EXT4_HT_MOVE_EXTENTS, 2);
 146         if (IS_ERR(handle)) {
 147                 err = -EINVAL;
 148                 goto swap_boot_out;
 149         }
 150
 151         /* Protect extent tree against block allocations via delalloc */
 152         ext4_double_down_write_data_sem(inode, inode_bl);
 153
 154         if (inode_bl->i_nlink == 0) {
 155                 /* this inode has never been used as a BOOT_LOADER */
 156                 set_nlink(inode_bl, 1);
 157                 i_uid_write(inode_bl, 0);
 158                 i_gid_write(inode_bl, 0);
 159                 inode_bl->i_flags = 0;
 160                 ei_bl->i_flags = 0;
 161                 inode_bl->i_version = 1;
 162                 i_size_write(inode_bl, 0);
 163                 inode_bl->i_mode = S_IFREG;
 164                 if (EXT4_HAS_INCOMPAT_FEATURE(sb,
 165                                               EXT4_FEATURE_INCOMPAT_EXTENTS)) {
 166                         ext4_set_inode_flag(inode_bl, EXT4_INODE_EXTENTS);
 167                         ext4_ext_tree_init(handle, inode_bl);
 168                 } else
 169                         memset(ei_bl->i_data, 0, sizeof(ei_bl->i_data));
 170         }
 171
 172         swap_inode_data(inode, inode_bl);
 173
 174         inode->i_ctime = inode_bl->i_ctime = ext4_current_time(inode);
 175
 176         spin_lock(&sbi->s_next_gen_lock);
 177         inode->i_generation = sbi->s_next_generation++;
 178         inode_bl->i_generation = sbi->s_next_generation++;
 179         spin_unlock(&sbi->s_next_gen_lock);
 180
 181         ext4_discard_preallocations(inode);
 182
 183         err = ext4_mark_inode_dirty(handle, inode);
 184         if (err < 0) {
 185                 ext4_warning(inode->i_sb,
 186                         "couldn't mark inode #%lu dirty (err %d)",
 187                         inode->i_ino, err);
 188                 /* Revert all changes: */
 189                 swap_inode_data(inode, inode_bl);
 190         } else {
 191                 err = ext4_mark_inode_dirty(handle, inode_bl);
 192                 if (err < 0) {
 193                         ext4_warning(inode_bl->i_sb,
 194                                 "couldn't mark inode #%lu dirty (err %d)",
 195                                 inode_bl->i_ino, err);
 196                         /* Revert all changes: */
 197                         swap_inode_data(inode, inode_bl);
 198                         ext4_mark_inode_dirty(handle, inode);
 199                 }
 200         }
 201
 202         ext4_journal_stop(handle);
 203
 204         ext4_double_up_write_data_sem(inode, inode_bl);
 205
 206         ext4_inode_resume_unlocked_dio(inode);
 207         ext4_inode_resume_unlocked_dio(inode_bl);
 208
 209         ext4_inode_double_unlock(inode, inode_bl);
 210
 211         iput(inode_bl);
 212
 213 swap_boot_out:
 214         return err;
 215 }
 216
 217 long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 218 {
 219         struct inode *inode = file_inode(filp);
 220         struct super_block *sb = inode->i_sb;
 221         struct ext4_inode_info *ei = EXT4_I(inode);
 222         unsigned int flags;
 223
 224         ext4_debug("cmd = %u, arg = %lu\n", cmd, arg);
 225
 226         switch (cmd) {
 227         case EXT4_IOC_GETFLAGS:
 228                 ext4_get_inode_flags(ei);
 229                 flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
 230                 return put_user(flags, (int __user *) arg);
 231         case EXT4_IOC_SETFLAGS: {
 232                 handle_t *handle = NULL;
 233                 int err, migrate = 0;
 234                 struct ext4_iloc iloc;
 235                 unsigned int oldflags, mask, i;
 236                 unsigned int jflag;
 237
 238                 if (!inode_owner_or_capable(inode))
 239                         return -EACCES;
 240
 241                 if (get_user(flags, (int __user *) arg))
 242                         return -EFAULT;
 243
 244                 err = mnt_want_write_file(filp);
 245                 if (err)
 246                         return err;
 247
 248                 flags = ext4_mask_flags(inode->i_mode, flags);
 249
 250                 err = -EPERM;
 251                 mutex_lock(&inode->i_mutex);
 252                 /* Is it quota file? Do not allow user to mess with it */
 253                 if (IS_NOQUOTA(inode))
 254                         goto flags_out;
 255
 256                 oldflags = ei->i_flags;
 257
 258                 /* The JOURNAL_DATA flag is modifiable only by root */
 259                 jflag = flags & EXT4_JOURNAL_DATA_FL;
 260
 261                 /*
 262                  * The IMMUTABLE and APPEND_ONLY flags can only be changed by
 263                  * the relevant capability.
 264                  *
 265                  * This test looks nicer. Thanks to Pauline Middelink
 266                  */
 267                 if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) {
 268                         if (!capable(CAP_LINUX_IMMUTABLE))
 269                                 goto flags_out;
 270                 }
 271
 272                 /*
 273                  * The JOURNAL_DATA flag can only be changed by
 274                  * the relevant capability.
 275                  */
 276                 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) {
 277                         if (!capable(CAP_SYS_RESOURCE))
 278                                 goto flags_out;
 279                 }
 280                 if ((flags ^ oldflags) & EXT4_EXTENTS_FL)
 281                         migrate = 1;
 282
 283                 if (flags & EXT4_EOFBLOCKS_FL) {
 284                         /* we don't support adding EOFBLOCKS flag */
 285                         if (!(oldflags & EXT4_EOFBLOCKS_FL)) {
 286                                 err = -EOPNOTSUPP;
 287                                 goto flags_out;
 288                         }
 289                 } else if (oldflags & EXT4_EOFBLOCKS_FL)
 290                         ext4_truncate(inode);
 291
 292                 handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
 293                 if (IS_ERR(handle)) {
 294                         err = PTR_ERR(handle);
 295                         goto flags_out;
 296                 }
 297                 if (IS_SYNC(inode))
 298                         ext4_handle_sync(handle);
 299                 err = ext4_reserve_inode_write(handle, inode, &iloc);
 300                 if (err)
 301                         goto flags_err;
 302
 303                 for (i = 0, mask = 1; i < 32; i++, mask <<= 1) {
 304                         if (!(mask & EXT4_FL_USER_MODIFIABLE))
 305                                 continue;
 306                         if (mask & flags)
 307                                 ext4_set_inode_flag(inode, i);
 308                         else
 309                                 ext4_clear_inode_flag(inode, i);
 310                 }
 311
 312                 ext4_set_inode_flags(inode);
 313                 inode->i_ctime = ext4_current_time(inode);
 314
 315                 err = ext4_mark_iloc_dirty(handle, inode, &iloc);
 316 flags_err:
 317                 ext4_journal_stop(handle);
 318                 if (err)
 319                         goto flags_out;
 320
 321                 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
 322                         err = ext4_change_inode_journal_flag(inode, jflag);
 323                 if (err)
 324                         goto flags_out;
 325                 if (migrate) {
 326                         if (flags & EXT4_EXTENTS_FL)
 327                                 err = ext4_ext_migrate(inode);
 328                         else
 329                                 err = ext4_ind_migrate(inode);
 330                 }
 331
 332 flags_out:
 333                 mutex_unlock(&inode->i_mutex);
 334                 mnt_drop_write_file(filp);
 335                 return err;
 336         }
 337         case EXT4_IOC_GETVERSION:
 338         case EXT4_IOC_GETVERSION_OLD:
 339                 return put_user(inode->i_generation, (int __user *) arg);
 340         case EXT4_IOC_SETVERSION:
 341         case EXT4_IOC_SETVERSION_OLD: {
 342                 handle_t *handle;
 343                 struct ext4_iloc iloc;
 344                 __u32 generation;
 345                 int err;
 346
 347                 if (!inode_owner_or_capable(inode))
 348                         return -EPERM;
 349
 350                 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
 351                                 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
 352                         ext4_warning(sb, "Setting inode version is not "
 353                                      "supported with metadata_csum enabled.");
 354                         return -ENOTTY;
 355                 }
 356
 357                 err = mnt_want_write_file(filp);
 358                 if (err)
 359                         return err;
 360                 if (get_user(generation, (int __user *) arg)) {
 361                         err = -EFAULT;
 362                         goto setversion_out;
 363                 }
 364
 365                 mutex_lock(&inode->i_mutex);
 366                 handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
 367                 if (IS_ERR(handle)) {
 368                         err = PTR_ERR(handle);
 369                         goto unlock_out;
 370                 }
 371                 err = ext4_reserve_inode_write(handle, inode, &iloc);
 372                 if (err == 0) {
 373                         inode->i_ctime = ext4_current_time(inode);
 374                         inode->i_generation = generation;
 375                         err = ext4_mark_iloc_dirty(handle, inode, &iloc);
 376                 }
 377                 ext4_journal_stop(handle);
 378
 379 unlock_out:
 380                 mutex_unlock(&inode->i_mutex);
 381 setversion_out:
 382                 mnt_drop_write_file(filp);
 383                 return err;
 384         }
 385         case EXT4_IOC_GROUP_EXTEND: {
 386                 ext4_fsblk_t n_blocks_count;
 387                 int err, err2=0;
 388
 389                 err = ext4_resize_begin(sb);
 390                 if (err)
 391                         return err;
 392
 393                 if (get_user(n_blocks_count, (__u32 __user *)arg)) {
 394                         err = -EFAULT;
 395                         goto group_extend_out;
 396                 }
 397
 398                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 399                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 400                         ext4_msg(sb, KERN_ERR,
 401                                  "Online resizing not supported with bigalloc");
 402                         err = -EOPNOTSUPP;
 403                         goto group_extend_out;
 404                 }
 405
 406                 err = mnt_want_write_file(filp);
 407                 if (err)
 408                         goto group_extend_out;
 409
 410                 err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
 411                 if (EXT4_SB(sb)->s_journal) {
 412                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 413                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 414                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 415                 }
 416                 if (err == 0)
 417                         err = err2;
 418                 mnt_drop_write_file(filp);
 419 group_extend_out:
 420                 ext4_resize_end(sb);
 421                 return err;
 422         }
 423
 424         case EXT4_IOC_MOVE_EXT: {
 425                 struct move_extent me;
 426                 struct fd donor;
 427                 int err;
 428
 429                 if (!(filp->f_mode & FMODE_READ) ||
 430                     !(filp->f_mode & FMODE_WRITE))
 431                         return -EBADF;
 432
 433                 if (copy_from_user(&me,
 434                         (struct move_extent __user *)arg, sizeof(me)))
 435                         return -EFAULT;
 436                 me.moved_len = 0;
 437
 438                 donor = fdget(me.donor_fd);
 439                 if (!donor.file)
 440                         return -EBADF;
 441
 442                 if (!(donor.file->f_mode & FMODE_WRITE)) {
 443                         err = -EBADF;
 444                         goto mext_out;
 445                 }
 446
 447                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 448                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 449                         ext4_msg(sb, KERN_ERR,
 450                                  "Online defrag not supported with bigalloc");
 451                         err = -EOPNOTSUPP;
 452                         goto mext_out;
 453                 }
 454
 455                 err = mnt_want_write_file(filp);
 456                 if (err)
 457                         goto mext_out;
 458
 459                 err = ext4_move_extents(filp, donor.file, me.orig_start,
 460                                         me.donor_start, me.len, &me.moved_len);
 461                 mnt_drop_write_file(filp);
 462
 463                 if (copy_to_user((struct move_extent __user *)arg,
 464                                  &me, sizeof(me)))
 465                         err = -EFAULT;
 466 mext_out:
 467                 fdput(donor);
 468                 return err;
 469         }
 470
 471         case EXT4_IOC_GROUP_ADD: {
 472                 struct ext4_new_group_data input;
 473                 int err, err2=0;
 474
 475                 err = ext4_resize_begin(sb);
 476                 if (err)
 477                         return err;
 478
 479                 if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,
 480                                 sizeof(input))) {
 481                         err = -EFAULT;
 482                         goto group_add_out;
 483                 }
 484
 485                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 486                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 487                         ext4_msg(sb, KERN_ERR,
 488                                  "Online resizing not supported with bigalloc");
 489                         err = -EOPNOTSUPP;
 490                         goto group_add_out;
 491                 }
 492
 493                 err = mnt_want_write_file(filp);
 494                 if (err)
 495                         goto group_add_out;
 496
 497                 err = ext4_group_add(sb, &input);
 498                 if (EXT4_SB(sb)->s_journal) {
 499                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 500                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 501                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 502                 }
 503                 if (err == 0)
 504                         err = err2;
 505                 mnt_drop_write_file(filp);
 506                 if (!err && ext4_has_group_desc_csum(sb) &&
 507                     test_opt(sb, INIT_INODE_TABLE))
 508                         err = ext4_register_li_request(sb, input.group);
 509 group_add_out:
 510                 ext4_resize_end(sb);
 511                 return err;
 512         }
 513
 514         case EXT4_IOC_MIGRATE:
 515         {
 516                 int err;
 517                 if (!inode_owner_or_capable(inode))
 518                         return -EACCES;
 519
 520                 err = mnt_want_write_file(filp);
 521                 if (err)
 522                         return err;
 523                 /*
 524                  * inode_mutex prevent write and truncate on the file.
 525                  * Read still goes through. We take i_data_sem in
 526                  * ext4_ext_swap_inode_data before we switch the
 527                  * inode format to prevent read.
 528                  */
 529                 mutex_lock(&(inode->i_mutex));
 530                 err = ext4_ext_migrate(inode);
 531                 mutex_unlock(&(inode->i_mutex));
 532                 mnt_drop_write_file(filp);
 533                 return err;
 534         }
 535
 536         case EXT4_IOC_ALLOC_DA_BLKS:
 537         {
 538                 int err;
 539                 if (!inode_owner_or_capable(inode))
 540                         return -EACCES;
 541
 542                 err = mnt_want_write_file(filp);
 543                 if (err)
 544                         return err;
 545                 err = ext4_alloc_da_blocks(inode);
 546                 mnt_drop_write_file(filp);
 547                 return err;
 548         }
 549
 550         case EXT4_IOC_SWAP_BOOT:
 551                 if (!(filp->f_mode & FMODE_WRITE))
 552                         return -EBADF;
 553                 return swap_inode_boot_loader(sb, inode);
 554
 555         case EXT4_IOC_RESIZE_FS: {
 556                 ext4_fsblk_t n_blocks_count;
 557                 int err = 0, err2 = 0;
 558                 ext4_group_t o_group = EXT4_SB(sb)->s_groups_count;
 559
 560                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 561                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 562                         ext4_msg(sb, KERN_ERR,
 563                                  "Online resizing not (yet) supported with bigalloc");
 564                         return -EOPNOTSUPP;
 565                 }
 566
 567                 if (copy_from_user(&n_blocks_count, (__u64 __user *)arg,
 568                                    sizeof(__u64))) {
 569                         return -EFAULT;
 570                 }
 571
 572                 err = ext4_resize_begin(sb);
 573                 if (err)
 574                         return err;
 575
 576                 err = mnt_want_write_file(filp);
 577                 if (err)
 578                         goto resizefs_out;
 579
 580                 err = ext4_resize_fs(sb, n_blocks_count);
 581                 if (EXT4_SB(sb)->s_journal) {
 582                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 583                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 584                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 585                 }
 586                 if (err == 0)
 587                         err = err2;
 588                 mnt_drop_write_file(filp);
 589                 if (!err && (o_group > EXT4_SB(sb)->s_groups_count) &&
 590                     ext4_has_group_desc_csum(sb) &&
 591                     test_opt(sb, INIT_INODE_TABLE))
 592                         err = ext4_register_li_request(sb, o_group);
 593
 594 resizefs_out:
 595                 ext4_resize_end(sb);
 596                 return err;
 597         }
 598
 599         case FITRIM:
 600         {
 601                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
 602                 struct fstrim_range range;
 603                 int ret = 0;
 604
 605                 if (!capable(CAP_SYS_ADMIN))
 606                         return -EPERM;
 607
 608                 if (!blk_queue_discard(q))
 609                         return -EOPNOTSUPP;
 610
 611                 if (copy_from_user(&range, (struct fstrim_range __user *)arg,
 612                     sizeof(range)))
 613                         return -EFAULT;
 614
 615                 range.minlen = max((unsigned int)range.minlen,
 616                                    q->limits.discard_granularity);
 617                 ret = ext4_trim_fs(sb, &range);
 618                 if (ret < 0)
 619                         return ret;
 620
 621                 if (copy_to_user((struct fstrim_range __user *)arg, &range,
 622                     sizeof(range)))
 623                         return -EFAULT;
 624
 625                 return 0;
 626         }
 627
 628         default:
 629                 return -ENOTTY;
 630         }
 631 }
 632
 633 #ifdef CONFIG_COMPAT
 634 long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 635 {
 636         /* These are just misnamed, they actually get/put from/to user an int */
 637         switch (cmd) {
 638         case EXT4_IOC32_GETFLAGS:
 639                 cmd = EXT4_IOC_GETFLAGS;
 640                 break;
 641         case EXT4_IOC32_SETFLAGS:
 642                 cmd = EXT4_IOC_SETFLAGS;
 643                 break;
 644         case EXT4_IOC32_GETVERSION:
 645                 cmd = EXT4_IOC_GETVERSION;
 646                 break;
 647         case EXT4_IOC32_SETVERSION:
 648                 cmd = EXT4_IOC_SETVERSION;
 649                 break;
 650         case EXT4_IOC32_GROUP_EXTEND:
 651                 cmd = EXT4_IOC_GROUP_EXTEND;
 652                 break;
 653         case EXT4_IOC32_GETVERSION_OLD:
 654                 cmd = EXT4_IOC_GETVERSION_OLD;
 655                 break;
 656         case EXT4_IOC32_SETVERSION_OLD:
 657                 cmd = EXT4_IOC_SETVERSION_OLD;
 658                 break;
 659         case EXT4_IOC32_GETRSVSZ:
 660                 cmd = EXT4_IOC_GETRSVSZ;
 661                 break;
 662         case EXT4_IOC32_SETRSVSZ:
 663                 cmd = EXT4_IOC_SETRSVSZ;
 664                 break;
 665         case EXT4_IOC32_GROUP_ADD: {
 666                 struct compat_ext4_new_group_input __user *uinput;
 667                 struct ext4_new_group_input input;
 668                 mm_segment_t old_fs;
 669                 int err;
 670
 671                 uinput = compat_ptr(arg);
 672                 err = get_user(input.group, &uinput->group);
 673                 err |= get_user(input.block_bitmap, &uinput->block_bitmap);
 674                 err |= get_user(input.inode_bitmap, &uinput->inode_bitmap);
 675                 err |= get_user(input.inode_table, &uinput->inode_table);
 676                 err |= get_user(input.blocks_count, &uinput->blocks_count);
 677                 err |= get_user(input.reserved_blocks,
 678                                 &uinput->reserved_blocks);
 679                 if (err)
 680                         return -EFAULT;
 681                 old_fs = get_fs();
 682                 set_fs(KERNEL_DS);
 683                 err = ext4_ioctl(file, EXT4_IOC_GROUP_ADD,
 684                                  (unsigned long) &input);
 685                 set_fs(old_fs);
 686                 return err;
 687         }
 688         case EXT4_IOC_MOVE_EXT:
 689         case FITRIM:
 690         case EXT4_IOC_RESIZE_FS:
 691                 break;
 692         default:
 693                 return -ENOIOCTLCMD;
 694         }
 695         return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
 696 }
 697 #endif