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