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
 127                 ext4_set_inode_flags(inode);
 128                 inode->i_ctime = ext4_current_time(inode);
 129
 130                 err = ext4_mark_iloc_dirty(handle, inode, &iloc);
 131 flags_err:
 132                 ext4_journal_stop(handle);
 133                 if (err)
 134                         goto flags_out;
 135
 136                 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
 137                         err = ext4_change_inode_journal_flag(inode, jflag);
 138                 if (err)
 139                         goto flags_out;
 140                 if (migrate)
 141                         err = ext4_ext_migrate(inode);
 142 flags_out:
 143                 mutex_unlock(&inode->i_mutex);
 144                 mnt_drop_write_file(filp);
 145                 return err;
 146         }
 147         case EXT4_IOC_GETVERSION:
 148         case EXT4_IOC_GETVERSION_OLD:
 149                 return put_user(inode->i_generation, (int __user *) arg);
 150         case EXT4_IOC_SETVERSION:
 151         case EXT4_IOC_SETVERSION_OLD: {
 152                 handle_t *handle;
 153                 struct ext4_iloc iloc;
 154                 __u32 generation;
 155                 int err;
 156
 157                 if (!inode_owner_or_capable(inode))
 158                         return -EPERM;
 159
 160                 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
 161                                 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
 162                         ext4_warning(sb, "Setting inode version is not "
 163                                      "supported with metadata_csum enabled.");
 164                         return -ENOTTY;
 165                 }
 166
 167                 err = mnt_want_write_file(filp);
 168                 if (err)
 169                         return err;
 170                 if (get_user(generation, (int __user *) arg)) {
 171                         err = -EFAULT;
 172                         goto setversion_out;
 173                 }
 174
 175                 mutex_lock(&inode->i_mutex);
 176                 handle = ext4_journal_start(inode, 1);
 177                 if (IS_ERR(handle)) {
 178                         err = PTR_ERR(handle);
 179                         goto unlock_out;
 180                 }
 181                 err = ext4_reserve_inode_write(handle, inode, &iloc);
 182                 if (err == 0) {
 183                         inode->i_ctime = ext4_current_time(inode);
 184                         inode->i_generation = generation;
 185                         err = ext4_mark_iloc_dirty(handle, inode, &iloc);
 186                 }
 187                 ext4_journal_stop(handle);
 188
 189 unlock_out:
 190                 mutex_unlock(&inode->i_mutex);
 191 setversion_out:
 192                 mnt_drop_write_file(filp);
 193                 return err;
 194         }
 195         case EXT4_IOC_GROUP_EXTEND: {
 196                 ext4_fsblk_t n_blocks_count;
 197                 int err, err2=0;
 198
 199                 err = ext4_resize_begin(sb);
 200                 if (err)
 201                         return err;
 202
 203                 if (get_user(n_blocks_count, (__u32 __user *)arg)) {
 204                         err = -EFAULT;
 205                         goto group_extend_out;
 206                 }
 207
 208                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 209                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 210                         ext4_msg(sb, KERN_ERR,
 211                                  "Online resizing not supported with bigalloc");
 212                         err = -EOPNOTSUPP;
 213                         goto group_extend_out;
 214                 }
 215
 216                 err = mnt_want_write_file(filp);
 217                 if (err)
 218                         goto group_extend_out;
 219
 220                 err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
 221                 if (EXT4_SB(sb)->s_journal) {
 222                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 223                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 224                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 225                 }
 226                 if (err == 0)
 227                         err = err2;
 228                 mnt_drop_write_file(filp);
 229 group_extend_out:
 230                 ext4_resize_end(sb);
 231                 return err;
 232         }
 233
 234         case EXT4_IOC_MOVE_EXT: {
 235                 struct move_extent me;
 236                 struct file *donor_filp;
 237                 int err;
 238
 239                 if (!(filp->f_mode & FMODE_READ) ||
 240                     !(filp->f_mode & FMODE_WRITE))
 241                         return -EBADF;
 242
 243                 if (copy_from_user(&me,
 244                         (struct move_extent __user *)arg, sizeof(me)))
 245                         return -EFAULT;
 246                 me.moved_len = 0;
 247
 248                 donor_filp = fget(me.donor_fd);
 249                 if (!donor_filp)
 250                         return -EBADF;
 251
 252                 if (!(donor_filp->f_mode & FMODE_WRITE)) {
 253                         err = -EBADF;
 254                         goto mext_out;
 255                 }
 256
 257                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 258                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 259                         ext4_msg(sb, KERN_ERR,
 260                                  "Online defrag not supported with bigalloc");
 261                         return -EOPNOTSUPP;
 262                 }
 263
 264                 err = mnt_want_write_file(filp);
 265                 if (err)
 266                         goto mext_out;
 267
 268                 err = ext4_move_extents(filp, donor_filp, me.orig_start,
 269                                         me.donor_start, me.len, &me.moved_len);
 270                 mnt_drop_write_file(filp);
 271                 mnt_drop_write(filp->f_path.mnt);
 272
 273                 if (copy_to_user((struct move_extent __user *)arg,
 274                                  &me, sizeof(me)))
 275                         err = -EFAULT;
 276 mext_out:
 277                 fput(donor_filp);
 278                 return err;
 279         }
 280
 281         case EXT4_IOC_GROUP_ADD: {
 282                 struct ext4_new_group_data input;
 283                 int err, err2=0;
 284
 285                 err = ext4_resize_begin(sb);
 286                 if (err)
 287                         return err;
 288
 289                 if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,
 290                                 sizeof(input))) {
 291                         err = -EFAULT;
 292                         goto group_add_out;
 293                 }
 294
 295                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 296                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 297                         ext4_msg(sb, KERN_ERR,
 298                                  "Online resizing not supported with bigalloc");
 299                         err = -EOPNOTSUPP;
 300                         goto group_add_out;
 301                 }
 302
 303                 err = mnt_want_write_file(filp);
 304                 if (err)
 305                         goto group_add_out;
 306
 307                 err = ext4_group_add(sb, &input);
 308                 if (EXT4_SB(sb)->s_journal) {
 309                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 310                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 311                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 312                 }
 313                 if (err == 0)
 314                         err = err2;
 315                 mnt_drop_write_file(filp);
 316 group_add_out:
 317                 ext4_resize_end(sb);
 318                 return err;
 319         }
 320
 321         case EXT4_IOC_MIGRATE:
 322         {
 323                 int err;
 324                 if (!inode_owner_or_capable(inode))
 325                         return -EACCES;
 326
 327                 err = mnt_want_write_file(filp);
 328                 if (err)
 329                         return err;
 330                 /*
 331                  * inode_mutex prevent write and truncate on the file.
 332                  * Read still goes through. We take i_data_sem in
 333                  * ext4_ext_swap_inode_data before we switch the
 334                  * inode format to prevent read.
 335                  */
 336                 mutex_lock(&(inode->i_mutex));
 337                 err = ext4_ext_migrate(inode);
 338                 mutex_unlock(&(inode->i_mutex));
 339                 mnt_drop_write_file(filp);
 340                 return err;
 341         }
 342
 343         case EXT4_IOC_ALLOC_DA_BLKS:
 344         {
 345                 int err;
 346                 if (!inode_owner_or_capable(inode))
 347                         return -EACCES;
 348
 349                 err = mnt_want_write_file(filp);
 350                 if (err)
 351                         return err;
 352                 err = ext4_alloc_da_blocks(inode);
 353                 mnt_drop_write_file(filp);
 354                 return err;
 355         }
 356
 357         case EXT4_IOC_RESIZE_FS: {
 358                 ext4_fsblk_t n_blocks_count;
 359                 struct super_block *sb = inode->i_sb;
 360                 int err = 0, err2 = 0;
 361
 362                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 363                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 364                         ext4_msg(sb, KERN_ERR,
 365                                  "Online resizing not (yet) supported with bigalloc");
 366                         return -EOPNOTSUPP;
 367                 }
 368
 369                 if (EXT4_HAS_INCOMPAT_FEATURE(sb,
 370                                EXT4_FEATURE_INCOMPAT_META_BG)) {
 371                         ext4_msg(sb, KERN_ERR,
 372                                  "Online resizing not (yet) supported with meta_bg");
 373                         return -EOPNOTSUPP;
 374                 }
 375
 376                 if (copy_from_user(&n_blocks_count, (__u64 __user *)arg,
 377                                    sizeof(__u64))) {
 378                         return -EFAULT;
 379                 }
 380
 381                 if (n_blocks_count > MAX_32_NUM &&
 382                     !EXT4_HAS_INCOMPAT_FEATURE(sb,
 383                                                EXT4_FEATURE_INCOMPAT_64BIT)) {
 384                         ext4_msg(sb, KERN_ERR,
 385                                  "File system only supports 32-bit block numbers");
 386                         return -EOPNOTSUPP;
 387                 }
 388
 389                 err = ext4_resize_begin(sb);
 390                 if (err)
 391                         return err;
 392
 393                 err = mnt_want_write(filp->f_path.mnt);
 394                 if (err)
 395                         goto resizefs_out;
 396
 397                 err = ext4_resize_fs(sb, n_blocks_count);
 398                 if (EXT4_SB(sb)->s_journal) {
 399                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 400                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 401                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 402                 }
 403                 if (err == 0)
 404                         err = err2;
 405                 mnt_drop_write(filp->f_path.mnt);
 406 resizefs_out:
 407                 ext4_resize_end(sb);
 408                 return err;
 409         }
 410
 411         case FITRIM:
 412         {
 413                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
 414                 struct fstrim_range range;
 415                 int ret = 0;
 416
 417                 if (!capable(CAP_SYS_ADMIN))
 418                         return -EPERM;
 419
 420                 if (!blk_queue_discard(q))
 421                         return -EOPNOTSUPP;
 422
 423                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 424                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 425                         ext4_msg(sb, KERN_ERR,
 426                                  "FITRIM not supported with bigalloc");
 427                         return -EOPNOTSUPP;
 428                 }
 429
 430                 if (copy_from_user(&range, (struct fstrim_range __user *)arg,
 431                     sizeof(range)))
 432                         return -EFAULT;
 433
 434                 range.minlen = max((unsigned int)range.minlen,
 435                                    q->limits.discard_granularity);
 436                 ret = ext4_trim_fs(sb, &range);
 437                 if (ret < 0)
 438                         return ret;
 439
 440                 if (copy_to_user((struct fstrim_range __user *)arg, &range,
 441                     sizeof(range)))
 442                         return -EFAULT;
 443
 444                 return 0;
 445         }
 446
 447         default:
 448                 return -ENOTTY;
 449         }
 450 }
 451
 452 #ifdef CONFIG_COMPAT
 453 long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 454 {
 455         /* These are just misnamed, they actually get/put from/to user an int */
 456         switch (cmd) {
 457         case EXT4_IOC32_GETFLAGS:
 458                 cmd = EXT4_IOC_GETFLAGS;
 459                 break;
 460         case EXT4_IOC32_SETFLAGS:
 461                 cmd = EXT4_IOC_SETFLAGS;
 462                 break;
 463         case EXT4_IOC32_GETVERSION:
 464                 cmd = EXT4_IOC_GETVERSION;
 465                 break;
 466         case EXT4_IOC32_SETVERSION:
 467                 cmd = EXT4_IOC_SETVERSION;
 468                 break;
 469         case EXT4_IOC32_GROUP_EXTEND:
 470                 cmd = EXT4_IOC_GROUP_EXTEND;
 471                 break;
 472         case EXT4_IOC32_GETVERSION_OLD:
 473                 cmd = EXT4_IOC_GETVERSION_OLD;
 474                 break;
 475         case EXT4_IOC32_SETVERSION_OLD:
 476                 cmd = EXT4_IOC_SETVERSION_OLD;
 477                 break;
 478         case EXT4_IOC32_GETRSVSZ:
 479                 cmd = EXT4_IOC_GETRSVSZ;
 480                 break;
 481         case EXT4_IOC32_SETRSVSZ:
 482                 cmd = EXT4_IOC_SETRSVSZ;
 483                 break;
 484         case EXT4_IOC32_GROUP_ADD: {
 485                 struct compat_ext4_new_group_input __user *uinput;
 486                 struct ext4_new_group_input input;
 487                 mm_segment_t old_fs;
 488                 int err;
 489
 490                 uinput = compat_ptr(arg);
 491                 err = get_user(input.group, &uinput->group);
 492                 err |= get_user(input.block_bitmap, &uinput->block_bitmap);
 493                 err |= get_user(input.inode_bitmap, &uinput->inode_bitmap);
 494                 err |= get_user(input.inode_table, &uinput->inode_table);
 495                 err |= get_user(input.blocks_count, &uinput->blocks_count);
 496                 err |= get_user(input.reserved_blocks,
 497                                 &uinput->reserved_blocks);
 498                 if (err)
 499                         return -EFAULT;
 500                 old_fs = get_fs();
 501                 set_fs(KERNEL_DS);
 502                 err = ext4_ioctl(file, EXT4_IOC_GROUP_ADD,
 503                                  (unsigned long) &input);
 504                 set_fs(old_fs);
 505                 return err;
 506         }
 507         case EXT4_IOC_MOVE_EXT:
 508         case FITRIM:
 509         case EXT4_IOC_RESIZE_FS:
 510                 break;
 511         default:
 512                 return -ENOIOCTLCMD;
 513         }
 514         return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
 515 }
 516 #endif