fs/ext3/ioctl.c

   1 /*
   2  * linux/fs/ext3/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/jbd.h>
  12 #include <linux/capability.h>
  13 #include <linux/ext3_fs.h>
  14 #include <linux/ext3_jbd.h>
  15 #include <linux/mount.h>
  16 #include <linux/time.h>
  17 #include <linux/compat.h>
  18 #include <linux/smp_lock.h>
  19 #include <asm/uaccess.h>
  20
  21 int ext3_ioctl (struct inode * inode, struct file * filp, unsigned int cmd,
  22                 unsigned long arg)
  23 {
  24         struct ext3_inode_info *ei = EXT3_I(inode);
  25         unsigned int flags;
  26         unsigned short rsv_window_size;
  27
  28         ext3_debug ("cmd = %u, arg = %lu\n", cmd, arg);
  29
  30         switch (cmd) {
  31         case EXT3_IOC_GETFLAGS:
  32                 ext3_get_inode_flags(ei);
  33                 flags = ei->i_flags & EXT3_FL_USER_VISIBLE;
  34                 return put_user(flags, (int __user *) arg);
  35         case EXT3_IOC_SETFLAGS: {
  36                 handle_t *handle = NULL;
  37                 int err;
  38                 struct ext3_iloc iloc;
  39                 unsigned int oldflags;
  40                 unsigned int jflag;
  41
  42                 err = mnt_want_write(filp->f_path.mnt);
  43                 if (err)
  44                         return err;
  45
  46                 if (!is_owner_or_cap(inode)) {
  47                         err = -EACCES;
  48                         goto flags_out;
  49                 }
  50
  51                 if (get_user(flags, (int __user *) arg)) {
  52                         err = -EFAULT;
  53                         goto flags_out;
  54                 }
  55
  56                 if (!S_ISDIR(inode->i_mode))
  57                         flags &= ~EXT3_DIRSYNC_FL;
  58
  59                 mutex_lock(&inode->i_mutex);
  60                 /* Is it quota file? Do not allow user to mess with it */
  61                 if (IS_NOQUOTA(inode)) {
  62                         mutex_unlock(&inode->i_mutex);
  63                         err = -EPERM;
  64                         goto flags_out;
  65                 }
  66                 oldflags = ei->i_flags;
  67
  68                 /* The JOURNAL_DATA flag is modifiable only by root */
  69                 jflag = flags & EXT3_JOURNAL_DATA_FL;
  70
  71                 /*
  72                  * The IMMUTABLE and APPEND_ONLY flags can only be changed by
  73                  * the relevant capability.
  74                  *
  75                  * This test looks nicer. Thanks to Pauline Middelink
  76                  */
  77                 if ((flags ^ oldflags) & (EXT3_APPEND_FL | EXT3_IMMUTABLE_FL)) {
  78                         if (!capable(CAP_LINUX_IMMUTABLE)) {
  79                                 mutex_unlock(&inode->i_mutex);
  80                                 err = -EPERM;
  81                                 goto flags_out;
  82                         }
  83                 }
  84
  85                 /*
  86                  * The JOURNAL_DATA flag can only be changed by
  87                  * the relevant capability.
  88                  */
  89                 if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL)) {
  90                         if (!capable(CAP_SYS_RESOURCE)) {
  91                                 mutex_unlock(&inode->i_mutex);
  92                                 err = -EPERM;
  93                                 goto flags_out;
  94                         }
  95                 }
  96
  97
  98                 handle = ext3_journal_start(inode, 1);
  99                 if (IS_ERR(handle)) {
 100                         mutex_unlock(&inode->i_mutex);
 101                         err = PTR_ERR(handle);
 102                         goto flags_out;
 103                 }
 104                 if (IS_SYNC(inode))
 105                         handle->h_sync = 1;
 106                 err = ext3_reserve_inode_write(handle, inode, &iloc);
 107                 if (err)
 108                         goto flags_err;
 109
 110                 flags = flags & EXT3_FL_USER_MODIFIABLE;
 111                 flags |= oldflags & ~EXT3_FL_USER_MODIFIABLE;
 112                 ei->i_flags = flags;
 113
 114                 ext3_set_inode_flags(inode);
 115                 inode->i_ctime = CURRENT_TIME_SEC;
 116
 117                 err = ext3_mark_iloc_dirty(handle, inode, &iloc);
 118 flags_err:
 119                 ext3_journal_stop(handle);
 120                 if (err) {
 121                         mutex_unlock(&inode->i_mutex);
 122                         return err;
 123                 }
 124
 125                 if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL))
 126                         err = ext3_change_inode_journal_flag(inode, jflag);
 127                 mutex_unlock(&inode->i_mutex);
 128 flags_out:
 129                 mnt_drop_write(filp->f_path.mnt);
 130                 return err;
 131         }
 132         case EXT3_IOC_GETVERSION:
 133         case EXT3_IOC_GETVERSION_OLD:
 134                 return put_user(inode->i_generation, (int __user *) arg);
 135         case EXT3_IOC_SETVERSION:
 136         case EXT3_IOC_SETVERSION_OLD: {
 137                 handle_t *handle;
 138                 struct ext3_iloc iloc;
 139                 __u32 generation;
 140                 int err;
 141
 142                 if (!is_owner_or_cap(inode))
 143                         return -EPERM;
 144                 err = mnt_want_write(filp->f_path.mnt);
 145                 if (err)
 146                         return err;
 147                 if (get_user(generation, (int __user *) arg)) {
 148                         err = -EFAULT;
 149                         goto setversion_out;
 150                 }
 151                 handle = ext3_journal_start(inode, 1);
 152                 if (IS_ERR(handle)) {
 153                         err = PTR_ERR(handle);
 154                         goto setversion_out;
 155                 }
 156                 err = ext3_reserve_inode_write(handle, inode, &iloc);
 157                 if (err == 0) {
 158                         inode->i_ctime = CURRENT_TIME_SEC;
 159                         inode->i_generation = generation;
 160                         err = ext3_mark_iloc_dirty(handle, inode, &iloc);
 161                 }
 162                 ext3_journal_stop(handle);
 163 setversion_out:
 164                 mnt_drop_write(filp->f_path.mnt);
 165                 return err;
 166         }
 167 #ifdef CONFIG_JBD_DEBUG
 168         case EXT3_IOC_WAIT_FOR_READONLY:
 169                 /*
 170                  * This is racy - by the time we're woken up and running,
 171                  * the superblock could be released.  And the module could
 172                  * have been unloaded.  So sue me.
 173                  *
 174                  * Returns 1 if it slept, else zero.
 175                  */
 176                 {
 177                         struct super_block *sb = inode->i_sb;
 178                         DECLARE_WAITQUEUE(wait, current);
 179                         int ret = 0;
 180
 181                         set_current_state(TASK_INTERRUPTIBLE);
 182                         add_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait);
 183                         if (timer_pending(&EXT3_SB(sb)->turn_ro_timer)) {
 184                                 schedule();
 185                                 ret = 1;
 186                         }
 187                         remove_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait);
 188                         return ret;
 189                 }
 190 #endif
 191         case EXT3_IOC_GETRSVSZ:
 192                 if (test_opt(inode->i_sb, RESERVATION)
 193                         && S_ISREG(inode->i_mode)
 194                         && ei->i_block_alloc_info) {
 195                         rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
 196                         return put_user(rsv_window_size, (int __user *)arg);
 197                 }
 198                 return -ENOTTY;
 199         case EXT3_IOC_SETRSVSZ: {
 200                 int err;
 201
 202                 if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
 203                         return -ENOTTY;
 204
 205                 err = mnt_want_write(filp->f_path.mnt);
 206                 if (err)
 207                         return err;
 208
 209                 if (!is_owner_or_cap(inode)) {
 210                         err = -EACCES;
 211                         goto setrsvsz_out;
 212                 }
 213
 214                 if (get_user(rsv_window_size, (int __user *)arg)) {
 215                         err = -EFAULT;
 216                         goto setrsvsz_out;
 217                 }
 218
 219                 if (rsv_window_size > EXT3_MAX_RESERVE_BLOCKS)
 220                         rsv_window_size = EXT3_MAX_RESERVE_BLOCKS;
 221
 222                 /*
 223                  * need to allocate reservation structure for this inode
 224                  * before set the window size
 225                  */
 226                 mutex_lock(&ei->truncate_mutex);
 227                 if (!ei->i_block_alloc_info)
 228                         ext3_init_block_alloc_info(inode);
 229
 230                 if (ei->i_block_alloc_info){
 231                         struct ext3_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
 232                         rsv->rsv_goal_size = rsv_window_size;
 233                 }
 234                 mutex_unlock(&ei->truncate_mutex);
 235 setrsvsz_out:
 236                 mnt_drop_write(filp->f_path.mnt);
 237                 return err;
 238         }
 239         case EXT3_IOC_GROUP_EXTEND: {
 240                 ext3_fsblk_t n_blocks_count;
 241                 struct super_block *sb = inode->i_sb;
 242                 int err, err2;
 243
 244                 if (!capable(CAP_SYS_RESOURCE))
 245                         return -EPERM;
 246
 247                 err = mnt_want_write(filp->f_path.mnt);
 248                 if (err)
 249                         return err;
 250
 251                 if (get_user(n_blocks_count, (__u32 __user *)arg)) {
 252                         err = -EFAULT;
 253                         goto group_extend_out;
 254                 }
 255                 err = ext3_group_extend(sb, EXT3_SB(sb)->s_es, n_blocks_count);
 256                 journal_lock_updates(EXT3_SB(sb)->s_journal);
 257                 err2 = journal_flush(EXT3_SB(sb)->s_journal);
 258                 journal_unlock_updates(EXT3_SB(sb)->s_journal);
 259                 if (err == 0)
 260                         err = err2;
 261 group_extend_out:
 262                 mnt_drop_write(filp->f_path.mnt);
 263                 return err;
 264         }
 265         case EXT3_IOC_GROUP_ADD: {
 266                 struct ext3_new_group_data input;
 267                 struct super_block *sb = inode->i_sb;
 268                 int err, err2;
 269
 270                 if (!capable(CAP_SYS_RESOURCE))
 271                         return -EPERM;
 272
 273                 err = mnt_want_write(filp->f_path.mnt);
 274                 if (err)
 275                         return err;
 276
 277                 if (copy_from_user(&input, (struct ext3_new_group_input __user *)arg,
 278                                 sizeof(input))) {
 279                         err = -EFAULT;
 280                         goto group_add_out;
 281                 }
 282
 283                 err = ext3_group_add(sb, &input);
 284                 journal_lock_updates(EXT3_SB(sb)->s_journal);
 285                 err2 = journal_flush(EXT3_SB(sb)->s_journal);
 286                 journal_unlock_updates(EXT3_SB(sb)->s_journal);
 287                 if (err == 0)
 288                         err = err2;
 289 group_add_out:
 290                 mnt_drop_write(filp->f_path.mnt);
 291                 return err;
 292         }
 293
 294
 295         default:
 296                 return -ENOTTY;
 297         }
 298 }
 299
 300 #ifdef CONFIG_COMPAT
 301 long ext3_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 302 {
 303         struct inode *inode = file->f_path.dentry->d_inode;
 304         int ret;
 305
 306         /* These are just misnamed, they actually get/put from/to user an int */
 307         switch (cmd) {
 308         case EXT3_IOC32_GETFLAGS:
 309                 cmd = EXT3_IOC_GETFLAGS;
 310                 break;
 311         case EXT3_IOC32_SETFLAGS:
 312                 cmd = EXT3_IOC_SETFLAGS;
 313                 break;
 314         case EXT3_IOC32_GETVERSION:
 315                 cmd = EXT3_IOC_GETVERSION;
 316                 break;
 317         case EXT3_IOC32_SETVERSION:
 318                 cmd = EXT3_IOC_SETVERSION;
 319                 break;
 320         case EXT3_IOC32_GROUP_EXTEND:
 321                 cmd = EXT3_IOC_GROUP_EXTEND;
 322                 break;
 323         case EXT3_IOC32_GETVERSION_OLD:
 324                 cmd = EXT3_IOC_GETVERSION_OLD;
 325                 break;
 326         case EXT3_IOC32_SETVERSION_OLD:
 327                 cmd = EXT3_IOC_SETVERSION_OLD;
 328                 break;
 329 #ifdef CONFIG_JBD_DEBUG
 330         case EXT3_IOC32_WAIT_FOR_READONLY:
 331                 cmd = EXT3_IOC_WAIT_FOR_READONLY;
 332                 break;
 333 #endif
 334         case EXT3_IOC32_GETRSVSZ:
 335                 cmd = EXT3_IOC_GETRSVSZ;
 336                 break;
 337         case EXT3_IOC32_SETRSVSZ:
 338                 cmd = EXT3_IOC_SETRSVSZ;
 339                 break;
 340         case EXT3_IOC_GROUP_ADD:
 341                 break;
 342         default:
 343                 return -ENOIOCTLCMD;
 344         }
 345         lock_kernel();
 346         ret = ext3_ioctl(inode, file, cmd, (unsigned long) compat_ptr(arg));
 347         unlock_kernel();
 348         return ret;
 349 }
 350 #endif