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 long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
  22 {
  23         struct inode *inode = filp->f_dentry->d_inode;
  24         struct super_block *sb = inode->i_sb;
  25         struct ext4_inode_info *ei = EXT4_I(inode);
  26         unsigned int flags;
  27
  28         ext4_debug("cmd = %u, arg = %lu\n", cmd, arg);
  29
  30         switch (cmd) {
  31         case EXT4_IOC_GETFLAGS:
  32                 ext4_get_inode_flags(ei);
  33                 flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
  34                 return put_user(flags, (int __user *) arg);
  35         case EXT4_IOC_SETFLAGS: {
  36                 handle_t *handle = NULL;
  37                 int err, migrate = 0;
  38                 struct ext4_iloc iloc;
  39                 unsigned int oldflags, mask, i;
  40                 unsigned int jflag;
  41
  42                 if (!inode_owner_or_capable(inode))
  43                         return -EACCES;
  44
  45                 if (get_user(flags, (int __user *) arg))
  46                         return -EFAULT;
  47
  48                 err = mnt_want_write(filp->f_path.mnt);
  49                 if (err)
  50                         return err;
  51
  52                 flags = ext4_mask_flags(inode->i_mode, flags);
  53
  54                 err = -EPERM;
  55                 mutex_lock(&inode->i_mutex);
  56                 /* Is it quota file? Do not allow user to mess with it */
  57                 if (IS_NOQUOTA(inode))
  58                         goto flags_out;
  59
  60                 oldflags = ei->i_flags;
  61
  62                 /* The JOURNAL_DATA flag is modifiable only by root */
  63                 jflag = flags & EXT4_JOURNAL_DATA_FL;
  64
  65                 /*
  66                  * The IMMUTABLE and APPEND_ONLY flags can only be changed by
  67                  * the relevant capability.
  68                  *
  69                  * This test looks nicer. Thanks to Pauline Middelink
  70                  */
  71                 if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) {
  72                         if (!capable(CAP_LINUX_IMMUTABLE))
  73                                 goto flags_out;
  74                 }
  75
  76                 /*
  77                  * The JOURNAL_DATA flag can only be changed by
  78                  * the relevant capability.
  79                  */
  80                 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) {
  81                         if (!capable(CAP_SYS_RESOURCE))
  82                                 goto flags_out;
  83                 }
  84                 if (oldflags & EXT4_EXTENTS_FL) {
  85                         /* We don't support clearning extent flags */
  86                         if (!(flags & EXT4_EXTENTS_FL)) {
  87                                 err = -EOPNOTSUPP;
  88                                 goto flags_out;
  89                         }
  90                 } else if (flags & EXT4_EXTENTS_FL) {
  91                         /* migrate the file */
  92                         migrate = 1;
  93                         flags &= ~EXT4_EXTENTS_FL;
  94                 }
  95
  96                 if (flags & EXT4_EOFBLOCKS_FL) {
  97                         /* we don't support adding EOFBLOCKS flag */
  98                         if (!(oldflags & EXT4_EOFBLOCKS_FL)) {
  99                                 err = -EOPNOTSUPP;
 100                                 goto flags_out;
 101                         }
 102                 } else if (oldflags & EXT4_EOFBLOCKS_FL)
 103                         ext4_truncate(inode);
 104
 105                 handle = ext4_journal_start(inode, 1);
 106                 if (IS_ERR(handle)) {
 107                         err = PTR_ERR(handle);
 108                         goto flags_out;
 109                 }
 110                 if (IS_SYNC(inode))
 111                         ext4_handle_sync(handle);
 112                 err = ext4_reserve_inode_write(handle, inode, &iloc);
 113                 if (err)
 114                         goto flags_err;
 115
 116                 for (i = 0, mask = 1; i < 32; i++, mask <<= 1) {
 117                         if (!(mask & EXT4_FL_USER_MODIFIABLE))
 118                                 continue;
 119                         if (mask & flags)
 120                                 ext4_set_inode_flag(inode, i);
 121                         else
 122                                 ext4_clear_inode_flag(inode, i);
 123                 }
 124
 125                 ext4_set_inode_flags(inode);
 126                 inode->i_ctime = ext4_current_time(inode);
 127
 128                 err = ext4_mark_iloc_dirty(handle, inode, &iloc);
 129 flags_err:
 130                 ext4_journal_stop(handle);
 131                 if (err)
 132                         goto flags_out;
 133
 134                 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
 135                         err = ext4_change_inode_journal_flag(inode, jflag);
 136                 if (err)
 137                         goto flags_out;
 138                 if (migrate)
 139                         err = ext4_ext_migrate(inode);
 140 flags_out:
 141                 mutex_unlock(&inode->i_mutex);
 142                 mnt_drop_write(filp->f_path.mnt);
 143                 return err;
 144         }
 145         case EXT4_IOC_GETVERSION:
 146         case EXT4_IOC_GETVERSION_OLD:
 147                 return put_user(inode->i_generation, (int __user *) arg);
 148         case EXT4_IOC_SETVERSION:
 149         case EXT4_IOC_SETVERSION_OLD: {
 150                 handle_t *handle;
 151                 struct ext4_iloc iloc;
 152                 __u32 generation;
 153                 int err;
 154
 155                 if (!inode_owner_or_capable(inode))
 156                         return -EPERM;
 157
 158                 err = mnt_want_write(filp->f_path.mnt);
 159                 if (err)
 160                         return err;
 161                 if (get_user(generation, (int __user *) arg)) {
 162                         err = -EFAULT;
 163                         goto setversion_out;
 164                 }
 165
 166                 handle = ext4_journal_start(inode, 1);
 167                 if (IS_ERR(handle)) {
 168                         err = PTR_ERR(handle);
 169                         goto setversion_out;
 170                 }
 171                 err = ext4_reserve_inode_write(handle, inode, &iloc);
 172                 if (err == 0) {
 173                         inode->i_ctime = ext4_current_time(inode);
 174                         inode->i_generation = generation;
 175                         err = ext4_mark_iloc_dirty(handle, inode, &iloc);
 176                 }
 177                 ext4_journal_stop(handle);
 178 setversion_out:
 179                 mnt_drop_write(filp->f_path.mnt);
 180                 return err;
 181         }
 182         case EXT4_IOC_GROUP_EXTEND: {
 183                 ext4_fsblk_t n_blocks_count;
 184                 int err, err2=0;
 185
 186                 err = ext4_resize_begin(sb);
 187                 if (err)
 188                         return err;
 189
 190                 if (get_user(n_blocks_count, (__u32 __user *)arg)) {
 191                         err = -EFAULT;
 192                         goto group_extend_out;
 193                 }
 194
 195                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 196                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 197                         ext4_msg(sb, KERN_ERR,
 198                                  "Online resizing not supported with bigalloc");
 199                         err = -EOPNOTSUPP;
 200                         goto group_extend_out;
 201                 }
 202
 203                 err = mnt_want_write(filp->f_path.mnt);
 204                 if (err)
 205                         goto group_extend_out;
 206
 207                 err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
 208                 if (EXT4_SB(sb)->s_journal) {
 209                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 210                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 211                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 212                 }
 213                 if (err == 0)
 214                         err = err2;
 215
 216                 mnt_drop_write(filp->f_path.mnt);
 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(filp->f_path.mnt);
 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(filp->f_path.mnt);
 259                 if (me.moved_len > 0)
 260                         file_remove_suid(donor_filp);
 261
 262                 if (copy_to_user((struct move_extent __user *)arg,
 263                                  &me, sizeof(me)))
 264                         err = -EFAULT;
 265 mext_out:
 266                 fput(donor_filp);
 267                 return err;
 268         }
 269
 270         case EXT4_IOC_GROUP_ADD: {
 271                 struct ext4_new_group_data input;
 272                 int err, err2=0;
 273
 274                 err = ext4_resize_begin(sb);
 275                 if (err)
 276                         return err;
 277
 278                 if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,
 279                                 sizeof(input))) {
 280                         err = -EFAULT;
 281                         goto group_add_out;
 282                 }
 283
 284                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 285                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 286                         ext4_msg(sb, KERN_ERR,
 287                                  "Online resizing not supported with bigalloc");
 288                         err = -EOPNOTSUPP;
 289                         goto group_add_out;
 290                 }
 291
 292                 err = mnt_want_write(filp->f_path.mnt);
 293                 if (err)
 294                         goto group_add_out;
 295
 296                 err = ext4_group_add(sb, &input);
 297                 if (EXT4_SB(sb)->s_journal) {
 298                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
 299                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
 300                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 301                 }
 302                 if (err == 0)
 303                         err = err2;
 304
 305                 mnt_drop_write(filp->f_path.mnt);
 306 group_add_out:
 307                 ext4_resize_end(sb);
 308                 return err;
 309         }
 310
 311         case EXT4_IOC_MIGRATE:
 312         {
 313                 int err;
 314                 if (!inode_owner_or_capable(inode))
 315                         return -EACCES;
 316
 317                 err = mnt_want_write(filp->f_path.mnt);
 318                 if (err)
 319                         return err;
 320                 /*
 321                  * inode_mutex prevent write and truncate on the file.
 322                  * Read still goes through. We take i_data_sem in
 323                  * ext4_ext_swap_inode_data before we switch the
 324                  * inode format to prevent read.
 325                  */
 326                 mutex_lock(&(inode->i_mutex));
 327                 err = ext4_ext_migrate(inode);
 328                 mutex_unlock(&(inode->i_mutex));
 329                 mnt_drop_write(filp->f_path.mnt);
 330                 return err;
 331         }
 332
 333         case EXT4_IOC_ALLOC_DA_BLKS:
 334         {
 335                 int err;
 336                 if (!inode_owner_or_capable(inode))
 337                         return -EACCES;
 338
 339                 err = mnt_want_write(filp->f_path.mnt);
 340                 if (err)
 341                         return err;
 342                 err = ext4_alloc_da_blocks(inode);
 343                 mnt_drop_write(filp->f_path.mnt);
 344                 return err;
 345         }
 346
 347         case FITRIM:
 348         {
 349                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
 350                 struct fstrim_range range;
 351                 int ret = 0;
 352
 353                 if (!capable(CAP_SYS_ADMIN))
 354                         return -EPERM;
 355
 356                 if (!blk_queue_discard(q))
 357                         return -EOPNOTSUPP;
 358
 359                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 360                                EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 361                         ext4_msg(sb, KERN_ERR,
 362                                  "FITRIM not supported with bigalloc");
 363                         return -EOPNOTSUPP;
 364                 }
 365
 366                 if (copy_from_user(&range, (struct fstrim_range __user *)arg,
 367                     sizeof(range)))
 368                         return -EFAULT;
 369
 370                 range.minlen = max((unsigned int)range.minlen,
 371                                    q->limits.discard_granularity);
 372                 ret = ext4_trim_fs(sb, &range);
 373                 if (ret < 0)
 374                         return ret;
 375
 376                 if (copy_to_user((struct fstrim_range __user *)arg, &range,
 377                     sizeof(range)))
 378                         return -EFAULT;
 379
 380                 return 0;
 381         }
 382
 383         default:
 384                 return -ENOTTY;
 385         }
 386 }
 387
 388 #ifdef CONFIG_COMPAT
 389 long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 390 {
 391         /* These are just misnamed, they actually get/put from/to user an int */
 392         switch (cmd) {
 393         case EXT4_IOC32_GETFLAGS:
 394                 cmd = EXT4_IOC_GETFLAGS;
 395                 break;
 396         case EXT4_IOC32_SETFLAGS:
 397                 cmd = EXT4_IOC_SETFLAGS;
 398                 break;
 399         case EXT4_IOC32_GETVERSION:
 400                 cmd = EXT4_IOC_GETVERSION;
 401                 break;
 402         case EXT4_IOC32_SETVERSION:
 403                 cmd = EXT4_IOC_SETVERSION;
 404                 break;
 405         case EXT4_IOC32_GROUP_EXTEND:
 406                 cmd = EXT4_IOC_GROUP_EXTEND;
 407                 break;
 408         case EXT4_IOC32_GETVERSION_OLD:
 409                 cmd = EXT4_IOC_GETVERSION_OLD;
 410                 break;
 411         case EXT4_IOC32_SETVERSION_OLD:
 412                 cmd = EXT4_IOC_SETVERSION_OLD;
 413                 break;
 414         case EXT4_IOC32_GETRSVSZ:
 415                 cmd = EXT4_IOC_GETRSVSZ;
 416                 break;
 417         case EXT4_IOC32_SETRSVSZ:
 418                 cmd = EXT4_IOC_SETRSVSZ;
 419                 break;
 420         case EXT4_IOC32_GROUP_ADD: {
 421                 struct compat_ext4_new_group_input __user *uinput;
 422                 struct ext4_new_group_input input;
 423                 mm_segment_t old_fs;
 424                 int err;
 425
 426                 uinput = compat_ptr(arg);
 427                 err = get_user(input.group, &uinput->group);
 428                 err |= get_user(input.block_bitmap, &uinput->block_bitmap);
 429                 err |= get_user(input.inode_bitmap, &uinput->inode_bitmap);
 430                 err |= get_user(input.inode_table, &uinput->inode_table);
 431                 err |= get_user(input.blocks_count, &uinput->blocks_count);
 432                 err |= get_user(input.reserved_blocks,
 433                                 &uinput->reserved_blocks);
 434                 if (err)
 435                         return -EFAULT;
 436                 old_fs = get_fs();
 437                 set_fs(KERNEL_DS);
 438                 err = ext4_ioctl(file, EXT4_IOC_GROUP_ADD,
 439                                  (unsigned long) &input);
 440                 set_fs(old_fs);
 441                 return err;
 442         }
 443         case EXT4_IOC_MOVE_EXT:
 444         case FITRIM:
 445                 break;
 446         default:
 447                 return -ENOIOCTLCMD;
 448         }
 449         return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
 450 }
 451 #endif