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