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;
  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                 flags = flags & EXT4_FL_USER_MODIFIABLE;
 119                 flags |= oldflags & ~EXT4_FL_USER_MODIFIABLE;
 120                 ei->i_flags = flags;
 121
 122                 ext4_set_inode_flags(inode);
 123                 inode->i_ctime = ext4_current_time(inode);
 124
 125                 err = ext4_mark_iloc_dirty(handle, inode, &iloc);
 126 flags_err:
 127                 ext4_journal_stop(handle);
 128                 if (err)
 129                         goto flags_out;
 130
 131                 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
 132                         err = ext4_change_inode_journal_flag(inode, jflag);
 133                 if (err)
 134                         goto flags_out;
 135                 if (migrate)
 136                         err = ext4_ext_migrate(inode);
 137 flags_out:
 138                 mutex_unlock(&inode->i_mutex);
 139                 mnt_drop_write_file(filp);
 140                 return err;
 141         }
 142         case EXT4_IOC_GETVERSION:
 143         case EXT4_IOC_GETVERSION_OLD:
 144                 return put_user(inode->i_generation, (int __user *) arg);
 145         case EXT4_IOC_SETVERSION:
 146         case EXT4_IOC_SETVERSION_OLD: {
 147                 handle_t *handle;
 148                 struct ext4_iloc iloc;
 149                 __u32 generation;
 150                 int err;
 151
 152                 if (!inode_owner_or_capable(inode))
 153                         return -EPERM;
 154
 155                 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
 156                                 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
 157                         ext4_warning(sb, "Setting inode version is not "
 158                                      "supported with metadata_csum enabled.");
 159                         return -ENOTTY;
 160                 }
 161
 162                 err = mnt_want_write_file(filp);
 163                 if (err)
 164                         return err;
 165                 if (get_user(generation, (int __user *) arg)) {
 166                         err = -EFAULT;
 167                         goto setversion_out;
 168                 }
 169
 170                 mutex_lock(&inode->i_mutex);
 171                 handle = ext4_journal_start(inode, 1);
 172                 if (IS_ERR(handle)) {
 173                         err = PTR_ERR(handle);
 174                         goto unlock_out;
 175                 }
 176                 err = ext4_reserve_inode_write(handle, inode, &iloc);
 177                 if (err == 0) {
 178                         inode->i_ctime = ext4_current_time(inode);
 179                         inode->i_generation = generation;
 180                         err = ext4_mark_iloc_dirty(handle, inode, &iloc);
 181                 }
 182                 ext4_journal_stop(handle);
 183
 184 unlock_out:
 185                 mutex_unlock(&inode->i_mutex);
 186 setversion_out:
 187                 mnt_drop_write_file(filp);
 188                 return err;
 189         }
 190         case EXT4_IOC_GROUP_EXTEND: {
 191                 ext4_fsblk_t n_blocks_count;
 192                 int err, err2=0;
 193
 194                 err = ext4_resize_begin(sb);
 195                 if (err)
 196                         return err;
 197
 198                 if (get_user(n_blocks_count, (__u32 __user *)arg)) {
 199                         err = -EFAULT;
 200                         goto group_extend_out;
 201                 }
 202
 203                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 204                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 205                         ext4_msg(sb, KERN_ERR,
 206                                  "Online resizing not supported with bigalloc");
 207                         err = -EOPNOTSUPP;
 208                         goto group_extend_out;
 209                 }
 210
 211                 err = mnt_want_write_file(filp);
 212                 if (err)
 213                         goto group_extend_out;
 214
 215                 err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
 216                 if (EXT4_SB(sb)->s_journal) {
 217                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 218                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 219                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 220                 }
 221                 if (err == 0)
 222                         err = err2;
 223                 mnt_drop_write_file(filp);
 224 group_extend_out:
 225                 ext4_resize_end(sb);
 226                 return err;
 227         }
 228
 229         case EXT4_IOC_MOVE_EXT: {
 230                 struct move_extent me;
 231                 struct file *donor_filp;
 232                 int err;
 233
 234                 if (!(filp->f_mode & FMODE_READ) ||
 235                     !(filp->f_mode & FMODE_WRITE))
 236                         return -EBADF;
 237
 238                 if (copy_from_user(&me,
 239                         (struct move_extent __user *)arg, sizeof(me)))
 240                         return -EFAULT;
 241                 me.moved_len = 0;
 242
 243                 donor_filp = fget(me.donor_fd);
 244                 if (!donor_filp)
 245                         return -EBADF;
 246
 247                 if (!(donor_filp->f_mode & FMODE_WRITE)) {
 248                         err = -EBADF;
 249                         goto mext_out;
 250                 }
 251
 252                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 253                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 254                         ext4_msg(sb, KERN_ERR,
 255                                  "Online defrag not supported with bigalloc");
 256                         return -EOPNOTSUPP;
 257                 }
 258
 259                 err = mnt_want_write_file(filp);
 260                 if (err)
 261                         goto mext_out;
 262
 263                 err = ext4_move_extents(filp, donor_filp, me.orig_start,
 264                                         me.donor_start, me.len, &me.moved_len);
 265                 mnt_drop_write_file(filp);
 266                 mnt_drop_write(filp->f_path.mnt);
 267
 268                 if (copy_to_user((struct move_extent __user *)arg,
 269                                  &me, sizeof(me)))
 270                         err = -EFAULT;
 271 mext_out:
 272                 fput(donor_filp);
 273                 return err;
 274         }
 275
 276         case EXT4_IOC_GROUP_ADD: {
 277                 struct ext4_new_group_data input;
 278                 int err, err2=0;
 279
 280                 err = ext4_resize_begin(sb);
 281                 if (err)
 282                         return err;
 283
 284                 if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,
 285                                 sizeof(input))) {
 286                         err = -EFAULT;
 287                         goto group_add_out;
 288                 }
 289
 290                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 291                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 292                         ext4_msg(sb, KERN_ERR,
 293                                  "Online resizing not supported with bigalloc");
 294                         err = -EOPNOTSUPP;
 295                         goto group_add_out;
 296                 }
 297
 298                 err = mnt_want_write_file(filp);
 299                 if (err)
 300                         goto group_add_out;
 301
 302                 err = ext4_group_add(sb, &input);
 303                 if (EXT4_SB(sb)->s_journal) {
 304                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 305                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 306                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 307                 }
 308                 if (err == 0)
 309                         err = err2;
 310                 mnt_drop_write_file(filp);
 311 group_add_out:
 312                 ext4_resize_end(sb);
 313                 return err;
 314         }
 315
 316         case EXT4_IOC_MIGRATE:
 317         {
 318                 int err;
 319                 if (!inode_owner_or_capable(inode))
 320                         return -EACCES;
 321
 322                 err = mnt_want_write_file(filp);
 323                 if (err)
 324                         return err;
 325                 /*
 326                  * inode_mutex prevent write and truncate on the file.
 327                  * Read still goes through. We take i_data_sem in
 328                  * ext4_ext_swap_inode_data before we switch the
 329                  * inode format to prevent read.
 330                  */
 331                 mutex_lock(&(inode->i_mutex));
 332                 err = ext4_ext_migrate(inode);
 333                 mutex_unlock(&(inode->i_mutex));
 334                 mnt_drop_write_file(filp);
 335                 return err;
 336         }
 337
 338         case EXT4_IOC_ALLOC_DA_BLKS:
 339         {
 340                 int err;
 341                 if (!inode_owner_or_capable(inode))
 342                         return -EACCES;
 343
 344                 err = mnt_want_write_file(filp);
 345                 if (err)
 346                         return err;
 347                 err = ext4_alloc_da_blocks(inode);
 348                 mnt_drop_write_file(filp);
 349                 return err;
 350         }
 351
 352         case EXT4_IOC_RESIZE_FS: {
 353                 ext4_fsblk_t n_blocks_count;
 354                 struct super_block *sb = inode->i_sb;
 355                 int err = 0, err2 = 0;
 356
 357                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 358                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 359                         ext4_msg(sb, KERN_ERR,
 360                                  "Online resizing not (yet) supported with bigalloc");
 361                         return -EOPNOTSUPP;
 362                 }
 363
 364                 if (EXT4_HAS_INCOMPAT_FEATURE(sb,
 365                                EXT4_FEATURE_INCOMPAT_META_BG)) {
 366                         ext4_msg(sb, KERN_ERR,
 367                                  "Online resizing not (yet) supported with meta_bg");
 368                         return -EOPNOTSUPP;
 369                 }
 370
 371                 if (copy_from_user(&n_blocks_count, (__u64 __user *)arg,
 372                                    sizeof(__u64))) {
 373                         return -EFAULT;
 374                 }
 375
 376                 if (n_blocks_count > MAX_32_NUM &&
 377                     !EXT4_HAS_INCOMPAT_FEATURE(sb,
 378                                                EXT4_FEATURE_INCOMPAT_64BIT)) {
 379                         ext4_msg(sb, KERN_ERR,
 380                                  "File system only supports 32-bit block numbers");
 381                         return -EOPNOTSUPP;
 382                 }
 383
 384                 err = ext4_resize_begin(sb);
 385                 if (err)
 386                         return err;
 387
 388                 err = mnt_want_write(filp->f_path.mnt);
 389                 if (err)
 390                         goto resizefs_out;
 391
 392                 err = ext4_resize_fs(sb, n_blocks_count);
 393                 if (EXT4_SB(sb)->s_journal) {
 394                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 395                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 396                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 397                 }
 398                 if (err == 0)
 399                         err = err2;
 400                 mnt_drop_write(filp->f_path.mnt);
 401 resizefs_out:
 402                 ext4_resize_end(sb);
 403                 return err;
 404         }
 405
 406         case FITRIM:
 407         {
 408                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
 409                 struct fstrim_range range;
 410                 int ret = 0;
 411
 412                 if (!capable(CAP_SYS_ADMIN))
 413                         return -EPERM;
 414
 415                 if (!blk_queue_discard(q))
 416                         return -EOPNOTSUPP;
 417
 418                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 419                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 420                         ext4_msg(sb, KERN_ERR,
 421                                  "FITRIM not supported with bigalloc");
 422                         return -EOPNOTSUPP;
 423                 }
 424
 425                 if (copy_from_user(&range, (struct fstrim_range __user *)arg,
 426                     sizeof(range)))
 427                         return -EFAULT;
 428
 429                 range.minlen = max((unsigned int)range.minlen,
 430                                    q->limits.discard_granularity);
 431                 ret = ext4_trim_fs(sb, &range);
 432                 if (ret < 0)
 433                         return ret;
 434
 435                 if (copy_to_user((struct fstrim_range __user *)arg, &range,
 436                     sizeof(range)))
 437                         return -EFAULT;
 438
 439                 return 0;
 440         }
 441
 442         default:
 443                 return -ENOTTY;
 444         }
 445 }
 446
 447 #ifdef CONFIG_COMPAT
 448 long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 449 {
 450         /* These are just misnamed, they actually get/put from/to user an int */
 451         switch (cmd) {
 452         case EXT4_IOC32_GETFLAGS:
 453                 cmd = EXT4_IOC_GETFLAGS;
 454                 break;
 455         case EXT4_IOC32_SETFLAGS:
 456                 cmd = EXT4_IOC_SETFLAGS;
 457                 break;
 458         case EXT4_IOC32_GETVERSION:
 459                 cmd = EXT4_IOC_GETVERSION;
 460                 break;
 461         case EXT4_IOC32_SETVERSION:
 462                 cmd = EXT4_IOC_SETVERSION;
 463                 break;
 464         case EXT4_IOC32_GROUP_EXTEND:
 465                 cmd = EXT4_IOC_GROUP_EXTEND;
 466                 break;
 467         case EXT4_IOC32_GETVERSION_OLD:
 468                 cmd = EXT4_IOC_GETVERSION_OLD;
 469                 break;
 470         case EXT4_IOC32_SETVERSION_OLD:
 471                 cmd = EXT4_IOC_SETVERSION_OLD;
 472                 break;
 473         case EXT4_IOC32_GETRSVSZ:
 474                 cmd = EXT4_IOC_GETRSVSZ;
 475                 break;
 476         case EXT4_IOC32_SETRSVSZ:
 477                 cmd = EXT4_IOC_SETRSVSZ;
 478                 break;
 479         case EXT4_IOC32_GROUP_ADD: {
 480                 struct compat_ext4_new_group_input __user *uinput;
 481                 struct ext4_new_group_input input;
 482                 mm_segment_t old_fs;
 483                 int err;
 484
 485                 uinput = compat_ptr(arg);
 486                 err = get_user(input.group, &uinput->group);
 487                 err |= get_user(input.block_bitmap, &uinput->block_bitmap);
 488                 err |= get_user(input.inode_bitmap, &uinput->inode_bitmap);
 489                 err |= get_user(input.inode_table, &uinput->inode_table);
 490                 err |= get_user(input.blocks_count, &uinput->blocks_count);
 491                 err |= get_user(input.reserved_blocks,
 492                                 &uinput->reserved_blocks);
 493                 if (err)
 494                         return -EFAULT;
 495                 old_fs = get_fs();
 496                 set_fs(KERNEL_DS);
 497                 err = ext4_ioctl(file, EXT4_IOC_GROUP_ADD,
 498                                  (unsigned long) &input);
 499                 set_fs(old_fs);
 500                 return err;
 501         }
 502         case EXT4_IOC_MOVE_EXT:
 503         case FITRIM:
 504         case EXT4_IOC_RESIZE_FS:
 505                 break;
 506         default:
 507                 return -ENOIOCTLCMD;
 508         }
 509         return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
 510 }
 511 #endif