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