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 <asm/uaccess.h>
  19
  20 long ext3_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
  21 {
  22         struct inode *inode = filp->f_dentry->d_inode;
  23         struct ext3_inode_info *ei = EXT3_I(inode);
  24         unsigned int flags;
  25         unsigned short rsv_window_size;
  26
  27         ext3_debug ("cmd = %u, arg = %lu\n", cmd, arg);
  28
  29         switch (cmd) {
  30         case EXT3_IOC_GETFLAGS:
  31                 ext3_get_inode_flags(ei);
  32                 flags = ei->i_flags & EXT3_FL_USER_VISIBLE;
  33                 return put_user(flags, (int __user *) arg);
  34         case EXT3_IOC_SETFLAGS: {
  35                 handle_t *handle = NULL;
  36                 int err;
  37                 struct ext3_iloc iloc;
  38                 unsigned int oldflags;
  39                 unsigned int jflag;
  40
  41                 if (!is_owner_or_cap(inode))
  42                         return -EACCES;
  43
  44                 if (get_user(flags, (int __user *) arg))
  45                         return -EFAULT;
  46
  47                 err = mnt_want_write(filp->f_path.mnt);
  48                 if (err)
  49                         return err;
  50
  51                 flags = ext3_mask_flags(inode->i_mode, flags);
  52
  53                 mutex_lock(&inode->i_mutex);
  54
  55                 /* Is it quota file? Do not allow user to mess with it */
  56                 err = -EPERM;
  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 & EXT3_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) & (EXT3_APPEND_FL | EXT3_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) & (EXT3_JOURNAL_DATA_FL)) {
  81                         if (!capable(CAP_SYS_RESOURCE))
  82                                 goto flags_out;
  83                 }
  84
  85                 handle = ext3_journal_start(inode, 1);
  86                 if (IS_ERR(handle)) {
  87                         err = PTR_ERR(handle);
  88                         goto flags_out;
  89                 }
  90                 if (IS_SYNC(inode))
  91                         handle->h_sync = 1;
  92                 err = ext3_reserve_inode_write(handle, inode, &iloc);
  93                 if (err)
  94                         goto flags_err;
  95
  96                 flags = flags & EXT3_FL_USER_MODIFIABLE;
  97                 flags |= oldflags & ~EXT3_FL_USER_MODIFIABLE;
  98                 ei->i_flags = flags;
  99
 100                 ext3_set_inode_flags(inode);
 101                 inode->i_ctime = CURRENT_TIME_SEC;
 102
 103                 err = ext3_mark_iloc_dirty(handle, inode, &iloc);
 104 flags_err:
 105                 ext3_journal_stop(handle);
 106                 if (err)
 107                         goto flags_out;
 108
 109                 if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL))
 110                         err = ext3_change_inode_journal_flag(inode, jflag);
 111 flags_out:
 112                 mutex_unlock(&inode->i_mutex);
 113                 mnt_drop_write(filp->f_path.mnt);
 114                 return err;
 115         }
 116         case EXT3_IOC_GETVERSION:
 117         case EXT3_IOC_GETVERSION_OLD:
 118                 return put_user(inode->i_generation, (int __user *) arg);
 119         case EXT3_IOC_SETVERSION:
 120         case EXT3_IOC_SETVERSION_OLD: {
 121                 handle_t *handle;
 122                 struct ext3_iloc iloc;
 123                 __u32 generation;
 124                 int err;
 125
 126                 if (!is_owner_or_cap(inode))
 127                         return -EPERM;
 128
 129                 err = mnt_want_write(filp->f_path.mnt);
 130                 if (err)
 131                         return err;
 132                 if (get_user(generation, (int __user *) arg)) {
 133                         err = -EFAULT;
 134                         goto setversion_out;
 135                 }
 136
 137                 handle = ext3_journal_start(inode, 1);
 138                 if (IS_ERR(handle)) {
 139                         err = PTR_ERR(handle);
 140                         goto setversion_out;
 141                 }
 142                 err = ext3_reserve_inode_write(handle, inode, &iloc);
 143                 if (err == 0) {
 144                         inode->i_ctime = CURRENT_TIME_SEC;
 145                         inode->i_generation = generation;
 146                         err = ext3_mark_iloc_dirty(handle, inode, &iloc);
 147                 }
 148                 ext3_journal_stop(handle);
 149 setversion_out:
 150                 mnt_drop_write(filp->f_path.mnt);
 151                 return err;
 152         }
 153 #ifdef CONFIG_JBD_DEBUG
 154         case EXT3_IOC_WAIT_FOR_READONLY:
 155                 /*
 156                  * This is racy - by the time we're woken up and running,
 157                  * the superblock could be released.  And the module could
 158                  * have been unloaded.  So sue me.
 159                  *
 160                  * Returns 1 if it slept, else zero.
 161                  */
 162                 {
 163                         struct super_block *sb = inode->i_sb;
 164                         DECLARE_WAITQUEUE(wait, current);
 165                         int ret = 0;
 166
 167                         set_current_state(TASK_INTERRUPTIBLE);
 168                         add_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait);
 169                         if (timer_pending(&EXT3_SB(sb)->turn_ro_timer)) {
 170                                 schedule();
 171                                 ret = 1;
 172                         }
 173                         remove_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait);
 174                         return ret;
 175                 }
 176 #endif
 177         case EXT3_IOC_GETRSVSZ:
 178                 if (test_opt(inode->i_sb, RESERVATION)
 179                         && S_ISREG(inode->i_mode)
 180                         && ei->i_block_alloc_info) {
 181                         rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
 182                         return put_user(rsv_window_size, (int __user *)arg);
 183                 }
 184                 return -ENOTTY;
 185         case EXT3_IOC_SETRSVSZ: {
 186                 int err;
 187
 188                 if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
 189                         return -ENOTTY;
 190
 191                 err = mnt_want_write(filp->f_path.mnt);
 192                 if (err)
 193                         return err;
 194
 195                 if (!is_owner_or_cap(inode)) {
 196                         err = -EACCES;
 197                         goto setrsvsz_out;
 198                 }
 199
 200                 if (get_user(rsv_window_size, (int __user *)arg)) {
 201                         err = -EFAULT;
 202                         goto setrsvsz_out;
 203                 }
 204
 205                 if (rsv_window_size > EXT3_MAX_RESERVE_BLOCKS)
 206                         rsv_window_size = EXT3_MAX_RESERVE_BLOCKS;
 207
 208                 /*
 209                  * need to allocate reservation structure for this inode
 210                  * before set the window size
 211                  */
 212                 mutex_lock(&ei->truncate_mutex);
 213                 if (!ei->i_block_alloc_info)
 214                         ext3_init_block_alloc_info(inode);
 215
 216                 if (ei->i_block_alloc_info){
 217                         struct ext3_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
 218                         rsv->rsv_goal_size = rsv_window_size;
 219                 }
 220                 mutex_unlock(&ei->truncate_mutex);
 221 setrsvsz_out:
 222                 mnt_drop_write(filp->f_path.mnt);
 223                 return err;
 224         }
 225         case EXT3_IOC_GROUP_EXTEND: {
 226                 ext3_fsblk_t n_blocks_count;
 227                 struct super_block *sb = inode->i_sb;
 228                 int err, err2;
 229
 230                 if (!capable(CAP_SYS_RESOURCE))
 231                         return -EPERM;
 232
 233                 err = mnt_want_write(filp->f_path.mnt);
 234                 if (err)
 235                         return err;
 236
 237                 if (get_user(n_blocks_count, (__u32 __user *)arg)) {
 238                         err = -EFAULT;
 239                         goto group_extend_out;
 240                 }
 241                 err = ext3_group_extend(sb, EXT3_SB(sb)->s_es, n_blocks_count);
 242                 journal_lock_updates(EXT3_SB(sb)->s_journal);
 243                 err2 = journal_flush(EXT3_SB(sb)->s_journal);
 244                 journal_unlock_updates(EXT3_SB(sb)->s_journal);
 245                 if (err == 0)
 246                         err = err2;
 247 group_extend_out:
 248                 mnt_drop_write(filp->f_path.mnt);
 249                 return err;
 250         }
 251         case EXT3_IOC_GROUP_ADD: {
 252                 struct ext3_new_group_data input;
 253                 struct super_block *sb = inode->i_sb;
 254                 int err, err2;
 255
 256                 if (!capable(CAP_SYS_RESOURCE))
 257                         return -EPERM;
 258
 259                 err = mnt_want_write(filp->f_path.mnt);
 260                 if (err)
 261                         return err;
 262
 263                 if (copy_from_user(&input, (struct ext3_new_group_input __user *)arg,
 264                                 sizeof(input))) {
 265                         err = -EFAULT;
 266                         goto group_add_out;
 267                 }
 268
 269                 err = ext3_group_add(sb, &input);
 270                 journal_lock_updates(EXT3_SB(sb)->s_journal);
 271                 err2 = journal_flush(EXT3_SB(sb)->s_journal);
 272                 journal_unlock_updates(EXT3_SB(sb)->s_journal);
 273                 if (err == 0)
 274                         err = err2;
 275 group_add_out:
 276                 mnt_drop_write(filp->f_path.mnt);
 277                 return err;
 278         }
 279
 280
 281         default:
 282                 return -ENOTTY;
 283         }
 284 }
 285
 286 #ifdef CONFIG_COMPAT
 287 long ext3_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 288 {
 289         /* These are just misnamed, they actually get/put from/to user an int */
 290         switch (cmd) {
 291         case EXT3_IOC32_GETFLAGS:
 292                 cmd = EXT3_IOC_GETFLAGS;
 293                 break;
 294         case EXT3_IOC32_SETFLAGS:
 295                 cmd = EXT3_IOC_SETFLAGS;
 296                 break;
 297         case EXT3_IOC32_GETVERSION:
 298                 cmd = EXT3_IOC_GETVERSION;
 299                 break;
 300         case EXT3_IOC32_SETVERSION:
 301                 cmd = EXT3_IOC_SETVERSION;
 302                 break;
 303         case EXT3_IOC32_GROUP_EXTEND:
 304                 cmd = EXT3_IOC_GROUP_EXTEND;
 305                 break;
 306         case EXT3_IOC32_GETVERSION_OLD:
 307                 cmd = EXT3_IOC_GETVERSION_OLD;
 308                 break;
 309         case EXT3_IOC32_SETVERSION_OLD:
 310                 cmd = EXT3_IOC_SETVERSION_OLD;
 311                 break;
 312 #ifdef CONFIG_JBD_DEBUG
 313         case EXT3_IOC32_WAIT_FOR_READONLY:
 314                 cmd = EXT3_IOC_WAIT_FOR_READONLY;
 315                 break;
 316 #endif
 317         case EXT3_IOC32_GETRSVSZ:
 318                 cmd = EXT3_IOC_GETRSVSZ;
 319                 break;
 320         case EXT3_IOC32_SETRSVSZ:
 321                 cmd = EXT3_IOC_SETRSVSZ;
 322                 break;
 323         case EXT3_IOC_GROUP_ADD:
 324                 break;
 325         default:
 326                 return -ENOIOCTLCMD;
 327         }
 328         return ext3_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
 329 }
 330 #endif