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