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 long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
  24 {
  25         struct inode *inode = filp->f_dentry->d_inode;
  26         struct super_block *sb = inode->i_sb;
  27         struct ext4_inode_info *ei = EXT4_I(inode);
  28         unsigned int flags;
  29
  30         ext4_debug("cmd = %u, arg = %lu\n", cmd, arg);
  31
  32         switch (cmd) {
  33         case EXT4_IOC_GETFLAGS:
  34                 ext4_get_inode_flags(ei);
  35                 flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
  36                 return put_user(flags, (int __user *) arg);
  37         case EXT4_IOC_SETFLAGS: {
  38                 handle_t *handle = NULL;
  39                 int err, migrate = 0;
  40                 struct ext4_iloc iloc;
  41                 unsigned int oldflags, mask, i;
  42                 unsigned int jflag;
  43
  44                 if (!inode_owner_or_capable(inode))
  45                         return -EACCES;
  46
  47                 if (get_user(flags, (int __user *) arg))
  48                         return -EFAULT;
  49
  50                 err = mnt_want_write_file(filp);
  51                 if (err)
  52                         return err;
  53
  54                 flags = ext4_mask_flags(inode->i_mode, flags);
  55
  56                 err = -EPERM;
  57                 mutex_lock(&inode->i_mutex);
  58                 /* Is it quota file? Do not allow user to mess with it */
  59                 if (IS_NOQUOTA(inode))
  60                         goto flags_out;
  61
  62                 oldflags = ei->i_flags;
  63
  64                 /* The JOURNAL_DATA flag is modifiable only by root */
  65                 jflag = flags & EXT4_JOURNAL_DATA_FL;
  66
  67                 /*
  68                  * The IMMUTABLE and APPEND_ONLY flags can only be changed by
  69                  * the relevant capability.
  70                  *
  71                  * This test looks nicer. Thanks to Pauline Middelink
  72                  */
  73                 if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) {
  74                         if (!capable(CAP_LINUX_IMMUTABLE))
  75                                 goto flags_out;
  76                 }
  77
  78                 /*
  79                  * The JOURNAL_DATA flag can only be changed by
  80                  * the relevant capability.
  81                  */
  82                 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) {
  83                         if (!capable(CAP_SYS_RESOURCE))
  84                                 goto flags_out;
  85                 }
  86                 if (oldflags & EXT4_EXTENTS_FL) {
  87                         /* We don't support clearning extent flags */
  88                         if (!(flags & EXT4_EXTENTS_FL)) {
  89                                 err = -EOPNOTSUPP;
  90                                 goto flags_out;
  91                         }
  92                 } else if (flags & EXT4_EXTENTS_FL) {
  93                         /* migrate the file */
  94                         migrate = 1;
  95                         flags &= ~EXT4_EXTENTS_FL;
  96                 }
  97
  98                 if (flags & EXT4_EOFBLOCKS_FL) {
  99                         /* we don't support adding EOFBLOCKS flag */
 100                         if (!(oldflags & EXT4_EOFBLOCKS_FL)) {
 101                                 err = -EOPNOTSUPP;
 102                                 goto flags_out;
 103                         }
 104                 } else if (oldflags & EXT4_EOFBLOCKS_FL)
 105                         ext4_truncate(inode);
 106
 107                 handle = ext4_journal_start(inode, 1);
 108                 if (IS_ERR(handle)) {
 109                         err = PTR_ERR(handle);
 110                         goto flags_out;
 111                 }
 112                 if (IS_SYNC(inode))
 113                         ext4_handle_sync(handle);
 114                 err = ext4_reserve_inode_write(handle, inode, &iloc);
 115                 if (err)
 116                         goto flags_err;
 117
 118                 for (i = 0, mask = 1; i < 32; i++, mask <<= 1) {
 119                         if (!(mask & EXT4_FL_USER_MODIFIABLE))
 120                                 continue;
 121                         if (mask & flags)
 122                                 ext4_set_inode_flag(inode, i);
 123                         else
 124                                 ext4_clear_inode_flag(inode, i);
 125                 }
 126                 ei->i_flags = flags;
 127
 128                 ext4_set_inode_flags(inode);
 129                 inode->i_ctime = ext4_current_time(inode);
 130
 131                 err = ext4_mark_iloc_dirty(handle, inode, &iloc);
 132 flags_err:
 133                 ext4_journal_stop(handle);
 134                 if (err)
 135                         goto flags_out;
 136
 137                 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
 138                         err = ext4_change_inode_journal_flag(inode, jflag);
 139                 if (err)
 140                         goto flags_out;
 141                 if (migrate)
 142                         err = ext4_ext_migrate(inode);
 143 flags_out:
 144                 mutex_unlock(&inode->i_mutex);
 145                 mnt_drop_write_file(filp);
 146                 return err;
 147         }
 148         case EXT4_IOC_GETVERSION:
 149         case EXT4_IOC_GETVERSION_OLD:
 150                 return put_user(inode->i_generation, (int __user *) arg);
 151         case EXT4_IOC_SETVERSION:
 152         case EXT4_IOC_SETVERSION_OLD: {
 153                 handle_t *handle;
 154                 struct ext4_iloc iloc;
 155                 __u32 generation;
 156                 int err;
 157
 158                 if (!inode_owner_or_capable(inode))
 159                         return -EPERM;
 160
 161                 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
 162                                 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
 163                         ext4_warning(sb, "Setting inode version is not "
 164                                      "supported with metadata_csum enabled.");
 165                         return -ENOTTY;
 166                 }
 167
 168                 err = mnt_want_write_file(filp);
 169                 if (err)
 170                         return err;
 171                 if (get_user(generation, (int __user *) arg)) {
 172                         err = -EFAULT;
 173                         goto setversion_out;
 174                 }
 175
 176                 mutex_lock(&inode->i_mutex);
 177                 handle = ext4_journal_start(inode, 1);
 178                 if (IS_ERR(handle)) {
 179                         err = PTR_ERR(handle);
 180                         goto unlock_out;
 181                 }
 182                 err = ext4_reserve_inode_write(handle, inode, &iloc);
 183                 if (err == 0) {
 184                         inode->i_ctime = ext4_current_time(inode);
 185                         inode->i_generation = generation;
 186                         err = ext4_mark_iloc_dirty(handle, inode, &iloc);
 187                 }
 188                 ext4_journal_stop(handle);
 189
 190 unlock_out:
 191                 mutex_unlock(&inode->i_mutex);
 192 setversion_out:
 193                 mnt_drop_write_file(filp);
 194                 return err;
 195         }
 196         case EXT4_IOC_GROUP_EXTEND: {
 197                 ext4_fsblk_t n_blocks_count;
 198                 int err, err2=0;
 199
 200                 err = ext4_resize_begin(sb);
 201                 if (err)
 202                         return err;
 203
 204                 if (get_user(n_blocks_count, (__u32 __user *)arg)) {
 205                         err = -EFAULT;
 206                         goto group_extend_out;
 207                 }
 208
 209                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 210                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 211                         ext4_msg(sb, KERN_ERR,
 212                                  "Online resizing not supported with bigalloc");
 213                         err = -EOPNOTSUPP;
 214                         goto group_extend_out;
 215                 }
 216
 217                 err = mnt_want_write_file(filp);
 218                 if (err)
 219                         goto group_extend_out;
 220
 221                 err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
 222                 if (EXT4_SB(sb)->s_journal) {
 223                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 224                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 225                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 226                 }
 227                 if (err == 0)
 228                         err = err2;
 229                 mnt_drop_write_file(filp);
 230 group_extend_out:
 231                 ext4_resize_end(sb);
 232                 return err;
 233         }
 234
 235         case EXT4_IOC_MOVE_EXT: {
 236                 struct move_extent me;
 237                 struct file *donor_filp;
 238                 int err;
 239
 240                 if (!(filp->f_mode & FMODE_READ) ||
 241                     !(filp->f_mode & FMODE_WRITE))
 242                         return -EBADF;
 243
 244                 if (copy_from_user(&me,
 245                         (struct move_extent __user *)arg, sizeof(me)))
 246                         return -EFAULT;
 247                 me.moved_len = 0;
 248
 249                 donor_filp = fget(me.donor_fd);
 250                 if (!donor_filp)
 251                         return -EBADF;
 252
 253                 if (!(donor_filp->f_mode & FMODE_WRITE)) {
 254                         err = -EBADF;
 255                         goto mext_out;
 256                 }
 257
 258                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 259                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 260                         ext4_msg(sb, KERN_ERR,
 261                                  "Online defrag not supported with bigalloc");
 262                         return -EOPNOTSUPP;
 263                 }
 264
 265                 err = mnt_want_write_file(filp);
 266                 if (err)
 267                         goto mext_out;
 268
 269                 err = ext4_move_extents(filp, donor_filp, me.orig_start,
 270                                         me.donor_start, me.len, &me.moved_len);
 271                 mnt_drop_write_file(filp);
 272                 mnt_drop_write(filp->f_path.mnt);
 273
 274                 if (copy_to_user((struct move_extent __user *)arg,
 275                                  &me, sizeof(me)))
 276                         err = -EFAULT;
 277 mext_out:
 278                 fput(donor_filp);
 279                 return err;
 280         }
 281
 282         case EXT4_IOC_GROUP_ADD: {
 283                 struct ext4_new_group_data input;
 284                 int err, err2=0;
 285
 286                 err = ext4_resize_begin(sb);
 287                 if (err)
 288                         return err;
 289
 290                 if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,
 291                                 sizeof(input))) {
 292                         err = -EFAULT;
 293                         goto group_add_out;
 294                 }
 295
 296                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 297                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 298                         ext4_msg(sb, KERN_ERR,
 299                                  "Online resizing not supported with bigalloc");
 300                         err = -EOPNOTSUPP;
 301                         goto group_add_out;
 302                 }
 303
 304                 err = mnt_want_write_file(filp);
 305                 if (err)
 306                         goto group_add_out;
 307
 308                 err = ext4_group_add(sb, &input);
 309                 if (EXT4_SB(sb)->s_journal) {
 310                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 311                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 312                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 313                 }
 314                 if (err == 0)
 315                         err = err2;
 316                 mnt_drop_write_file(filp);
 317 group_add_out:
 318                 ext4_resize_end(sb);
 319                 return err;
 320         }
 321
 322         case EXT4_IOC_MIGRATE:
 323         {
 324                 int err;
 325                 if (!inode_owner_or_capable(inode))
 326                         return -EACCES;
 327
 328                 err = mnt_want_write_file(filp);
 329                 if (err)
 330                         return err;
 331                 /*
 332                  * inode_mutex prevent write and truncate on the file.
 333                  * Read still goes through. We take i_data_sem in
 334                  * ext4_ext_swap_inode_data before we switch the
 335                  * inode format to prevent read.
 336                  */
 337                 mutex_lock(&(inode->i_mutex));
 338                 err = ext4_ext_migrate(inode);
 339                 mutex_unlock(&(inode->i_mutex));
 340                 mnt_drop_write_file(filp);
 341                 return err;
 342         }
 343
 344         case EXT4_IOC_ALLOC_DA_BLKS:
 345         {
 346                 int err;
 347                 if (!inode_owner_or_capable(inode))
 348                         return -EACCES;
 349
 350                 err = mnt_want_write_file(filp);
 351                 if (err)
 352                         return err;
 353                 err = ext4_alloc_da_blocks(inode);
 354                 mnt_drop_write_file(filp);
 355                 return err;
 356         }
 357
 358         case EXT4_IOC_RESIZE_FS: {
 359                 ext4_fsblk_t n_blocks_count;
 360                 struct super_block *sb = inode->i_sb;
 361                 int err = 0, err2 = 0;
 362
 363                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 364                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 365                         ext4_msg(sb, KERN_ERR,
 366                                  "Online resizing not (yet) supported with bigalloc");
 367                         return -EOPNOTSUPP;
 368                 }
 369
 370                 if (EXT4_HAS_INCOMPAT_FEATURE(sb,
 371                                EXT4_FEATURE_INCOMPAT_META_BG)) {
 372                         ext4_msg(sb, KERN_ERR,
 373                                  "Online resizing not (yet) supported with meta_bg");
 374                         return -EOPNOTSUPP;
 375                 }
 376
 377                 if (copy_from_user(&n_blocks_count, (__u64 __user *)arg,
 378                                    sizeof(__u64))) {
 379                         return -EFAULT;
 380                 }
 381
 382                 if (n_blocks_count > MAX_32_NUM &&
 383                     !EXT4_HAS_INCOMPAT_FEATURE(sb,
 384                                                EXT4_FEATURE_INCOMPAT_64BIT)) {
 385                         ext4_msg(sb, KERN_ERR,
 386                                  "File system only supports 32-bit block numbers");
 387                         return -EOPNOTSUPP;
 388                 }
 389
 390                 err = ext4_resize_begin(sb);
 391                 if (err)
 392                         return err;
 393
 394                 err = mnt_want_write(filp->f_path.mnt);
 395                 if (err)
 396                         goto resizefs_out;
 397
 398                 err = ext4_resize_fs(sb, n_blocks_count);
 399                 if (EXT4_SB(sb)->s_journal) {
 400                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 401                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 402                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 403                 }
 404                 if (err == 0)
 405                         err = err2;
 406                 mnt_drop_write(filp->f_path.mnt);
 407 resizefs_out:
 408                 ext4_resize_end(sb);
 409                 return err;
 410         }
 411
 412         case FITRIM:
 413         {
 414                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
 415                 struct fstrim_range range;
 416                 int ret = 0;
 417
 418                 if (!capable(CAP_SYS_ADMIN))
 419                         return -EPERM;
 420
 421                 if (!blk_queue_discard(q))
 422                         return -EOPNOTSUPP;
 423
 424                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 425                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 426                         ext4_msg(sb, KERN_ERR,
 427                                  "FITRIM not supported with bigalloc");
 428                         return -EOPNOTSUPP;
 429                 }
 430
 431                 if (copy_from_user(&range, (struct fstrim_range __user *)arg,
 432                     sizeof(range)))
 433                         return -EFAULT;
 434
 435                 range.minlen = max((unsigned int)range.minlen,
 436                                    q->limits.discard_granularity);
 437                 ret = ext4_trim_fs(sb, &range);
 438                 if (ret < 0)
 439                         return ret;
 440
 441                 if (copy_to_user((struct fstrim_range __user *)arg, &range,
 442                     sizeof(range)))
 443                         return -EFAULT;
 444
 445                 return 0;
 446         }
 447
 448         default:
 449                 return -ENOTTY;
 450         }
 451 }
 452
 453 #ifdef CONFIG_COMPAT
 454 long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 455 {
 456         /* These are just misnamed, they actually get/put from/to user an int */
 457         switch (cmd) {
 458         case EXT4_IOC32_GETFLAGS:
 459                 cmd = EXT4_IOC_GETFLAGS;
 460                 break;
 461         case EXT4_IOC32_SETFLAGS:
 462                 cmd = EXT4_IOC_SETFLAGS;
 463                 break;
 464         case EXT4_IOC32_GETVERSION:
 465                 cmd = EXT4_IOC_GETVERSION;
 466                 break;
 467         case EXT4_IOC32_SETVERSION:
 468                 cmd = EXT4_IOC_SETVERSION;
 469                 break;
 470         case EXT4_IOC32_GROUP_EXTEND:
 471                 cmd = EXT4_IOC_GROUP_EXTEND;
 472                 break;
 473         case EXT4_IOC32_GETVERSION_OLD:
 474                 cmd = EXT4_IOC_GETVERSION_OLD;
 475                 break;
 476         case EXT4_IOC32_SETVERSION_OLD:
 477                 cmd = EXT4_IOC_SETVERSION_OLD;
 478                 break;
 479         case EXT4_IOC32_GETRSVSZ:
 480                 cmd = EXT4_IOC_GETRSVSZ;
 481                 break;
 482         case EXT4_IOC32_SETRSVSZ:
 483                 cmd = EXT4_IOC_SETRSVSZ;
 484                 break;
 485         case EXT4_IOC32_GROUP_ADD: {
 486                 struct compat_ext4_new_group_input __user *uinput;
 487                 struct ext4_new_group_input input;
 488                 mm_segment_t old_fs;
 489                 int err;
 490
 491                 uinput = compat_ptr(arg);
 492                 err = get_user(input.group, &uinput->group);
 493                 err |= get_user(input.block_bitmap, &uinput->block_bitmap);
 494                 err |= get_user(input.inode_bitmap, &uinput->inode_bitmap);
 495                 err |= get_user(input.inode_table, &uinput->inode_table);
 496                 err |= get_user(input.blocks_count, &uinput->blocks_count);
 497                 err |= get_user(input.reserved_blocks,
 498                                 &uinput->reserved_blocks);
 499                 if (err)
 500                         return -EFAULT;
 501                 old_fs = get_fs();
 502                 set_fs(KERNEL_DS);
 503                 err = ext4_ioctl(file, EXT4_IOC_GROUP_ADD,
 504                                  (unsigned long) &input);
 505                 set_fs(old_fs);
 506                 return err;
 507         }
 508         case EXT4_IOC_MOVE_EXT:
 509         case FITRIM:
 510         case EXT4_IOC_RESIZE_FS:
 511                 break;
 512         default:
 513                 return -ENOIOCTLCMD;
 514         }
 515         return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
 516 }
 517 #endif