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                 flags = ext3_mask_flags(inode->i_mode, flags);
  57
  58                 mutex_lock(&inode->i_mutex);
  59                 /* Is it quota file? Do not allow user to mess with it */
  60                 if (IS_NOQUOTA(inode)) {
  61                         mutex_unlock(&inode->i_mutex);
  62                         err = -EPERM;
  63                         goto flags_out;
  64                 }
  65                 oldflags = ei->i_flags;
  66
  67                 /* The JOURNAL_DATA flag is modifiable only by root */
  68                 jflag = flags & EXT3_JOURNAL_DATA_FL;
  69
  70                 /*
  71                  * The IMMUTABLE and APPEND_ONLY flags can only be changed by
  72                  * the relevant capability.
  73                  *
  74                  * This test looks nicer. Thanks to Pauline Middelink
  75                  */
  76                 if ((flags ^ oldflags) & (EXT3_APPEND_FL | EXT3_IMMUTABLE_FL)) {
  77                         if (!capable(CAP_LINUX_IMMUTABLE)) {
  78                                 mutex_unlock(&inode->i_mutex);
  79                                 err = -EPERM;
  80                                 goto flags_out;
  81                         }
  82                 }
  83
  84                 /*
  85                  * The JOURNAL_DATA flag can only be changed by
  86                  * the relevant capability.
  87                  */
  88                 if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL)) {
  89                         if (!capable(CAP_SYS_RESOURCE)) {
  90                                 mutex_unlock(&inode->i_mutex);
  91                                 err = -EPERM;
  92                                 goto flags_out;
  93                         }
  94                 }
  95
  96
  97                 handle = ext3_journal_start(inode, 1);
  98                 if (IS_ERR(handle)) {
  99                         mutex_unlock(&inode->i_mutex);
 100                         err = PTR_ERR(handle);
 101                         goto flags_out;
 102                 }
 103                 if (IS_SYNC(inode))
 104                         handle->h_sync = 1;
 105                 err = ext3_reserve_inode_write(handle, inode, &iloc);
 106                 if (err)
 107                         goto flags_err;
 108
 109                 flags = flags & EXT3_FL_USER_MODIFIABLE;
 110                 flags |= oldflags & ~EXT3_FL_USER_MODIFIABLE;
 111                 ei->i_flags = flags;
 112
 113                 ext3_set_inode_flags(inode);
 114                 inode->i_ctime = CURRENT_TIME_SEC;
 115
 116                 err = ext3_mark_iloc_dirty(handle, inode, &iloc);
 117 flags_err:
 118                 ext3_journal_stop(handle);
 119                 if (err) {
 120                         mutex_unlock(&inode->i_mutex);
 121                         return err;
 122                 }
 123
 124                 if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL))
 125                         err = ext3_change_inode_journal_flag(inode, jflag);
 126                 mutex_unlock(&inode->i_mutex);
 127 flags_out:
 128                 mnt_drop_write(filp->f_path.mnt);
 129                 return err;
 130         }
 131         case EXT3_IOC_GETVERSION:
 132         case EXT3_IOC_GETVERSION_OLD:
 133                 return put_user(inode->i_generation, (int __user *) arg);
 134         case EXT3_IOC_SETVERSION:
 135         case EXT3_IOC_SETVERSION_OLD: {
 136                 handle_t *handle;
 137                 struct ext3_iloc iloc;
 138                 __u32 generation;
 139                 int err;
 140
 141                 if (!is_owner_or_cap(inode))
 142                         return -EPERM;
 143                 err = mnt_want_write(filp->f_path.mnt);
 144                 if (err)
 145                         return err;
 146                 if (get_user(generation, (int __user *) arg)) {
 147                         err = -EFAULT;
 148                         goto setversion_out;
 149                 }
 150                 handle = ext3_journal_start(inode, 1);
 151                 if (IS_ERR(handle)) {
 152                         err = PTR_ERR(handle);
 153                         goto setversion_out;
 154                 }
 155                 err = ext3_reserve_inode_write(handle, inode, &iloc);
 156                 if (err == 0) {
 157                         inode->i_ctime = CURRENT_TIME_SEC;
 158                         inode->i_generation = generation;
 159                         err = ext3_mark_iloc_dirty(handle, inode, &iloc);
 160                 }
 161                 ext3_journal_stop(handle);
 162 setversion_out:
 163                 mnt_drop_write(filp->f_path.mnt);
 164                 return err;
 165         }
 166 #ifdef CONFIG_JBD_DEBUG
 167         case EXT3_IOC_WAIT_FOR_READONLY:
 168                 /*
 169                  * This is racy - by the time we're woken up and running,
 170                  * the superblock could be released.  And the module could
 171                  * have been unloaded.  So sue me.
 172                  *
 173                  * Returns 1 if it slept, else zero.
 174                  */
 175                 {
 176                         struct super_block *sb = inode->i_sb;
 177                         DECLARE_WAITQUEUE(wait, current);
 178                         int ret = 0;
 179
 180                         set_current_state(TASK_INTERRUPTIBLE);
 181                         add_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait);
 182                         if (timer_pending(&EXT3_SB(sb)->turn_ro_timer)) {
 183                                 schedule();
 184                                 ret = 1;
 185                         }
 186                         remove_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait);
 187                         return ret;
 188                 }
 189 #endif
 190         case EXT3_IOC_GETRSVSZ:
 191                 if (test_opt(inode->i_sb, RESERVATION)
 192                         && S_ISREG(inode->i_mode)
 193                         && ei->i_block_alloc_info) {
 194                         rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
 195                         return put_user(rsv_window_size, (int __user *)arg);
 196                 }
 197                 return -ENOTTY;
 198         case EXT3_IOC_SETRSVSZ: {
 199                 int err;
 200
 201                 if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
 202                         return -ENOTTY;
 203
 204                 err = mnt_want_write(filp->f_path.mnt);
 205                 if (err)
 206                         return err;
 207
 208                 if (!is_owner_or_cap(inode)) {
 209                         err = -EACCES;
 210                         goto setrsvsz_out;
 211                 }
 212
 213                 if (get_user(rsv_window_size, (int __user *)arg)) {
 214                         err = -EFAULT;
 215                         goto setrsvsz_out;
 216                 }
 217
 218                 if (rsv_window_size > EXT3_MAX_RESERVE_BLOCKS)
 219                         rsv_window_size = EXT3_MAX_RESERVE_BLOCKS;
 220
 221                 /*
 222                  * need to allocate reservation structure for this inode
 223                  * before set the window size
 224                  */
 225                 mutex_lock(&ei->truncate_mutex);
 226                 if (!ei->i_block_alloc_info)
 227                         ext3_init_block_alloc_info(inode);
 228
 229                 if (ei->i_block_alloc_info){
 230                         struct ext3_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
 231                         rsv->rsv_goal_size = rsv_window_size;
 232                 }
 233                 mutex_unlock(&ei->truncate_mutex);
 234 setrsvsz_out:
 235                 mnt_drop_write(filp->f_path.mnt);
 236                 return err;
 237         }
 238         case EXT3_IOC_GROUP_EXTEND: {
 239                 ext3_fsblk_t n_blocks_count;
 240                 struct super_block *sb = inode->i_sb;
 241                 int err, err2;
 242
 243                 if (!capable(CAP_SYS_RESOURCE))
 244                         return -EPERM;
 245
 246                 err = mnt_want_write(filp->f_path.mnt);
 247                 if (err)
 248                         return err;
 249
 250                 if (get_user(n_blocks_count, (__u32 __user *)arg)) {
 251                         err = -EFAULT;
 252                         goto group_extend_out;
 253                 }
 254                 err = ext3_group_extend(sb, EXT3_SB(sb)->s_es, n_blocks_count);
 255                 journal_lock_updates(EXT3_SB(sb)->s_journal);
 256                 err2 = journal_flush(EXT3_SB(sb)->s_journal);
 257                 journal_unlock_updates(EXT3_SB(sb)->s_journal);
 258                 if (err == 0)
 259                         err = err2;
 260 group_extend_out:
 261                 mnt_drop_write(filp->f_path.mnt);
 262                 return err;
 263         }
 264         case EXT3_IOC_GROUP_ADD: {
 265                 struct ext3_new_group_data input;
 266                 struct super_block *sb = inode->i_sb;
 267                 int err, err2;
 268
 269                 if (!capable(CAP_SYS_RESOURCE))
 270                         return -EPERM;
 271
 272                 err = mnt_want_write(filp->f_path.mnt);
 273                 if (err)
 274                         return err;
 275
 276                 if (copy_from_user(&input, (struct ext3_new_group_input __user *)arg,
 277                                 sizeof(input))) {
 278                         err = -EFAULT;
 279                         goto group_add_out;
 280                 }
 281
 282                 err = ext3_group_add(sb, &input);
 283                 journal_lock_updates(EXT3_SB(sb)->s_journal);
 284                 err2 = journal_flush(EXT3_SB(sb)->s_journal);
 285                 journal_unlock_updates(EXT3_SB(sb)->s_journal);
 286                 if (err == 0)
 287                         err = err2;
 288 group_add_out:
 289                 mnt_drop_write(filp->f_path.mnt);
 290                 return err;
 291         }
 292
 293
 294         default:
 295                 return -ENOTTY;
 296         }
 297 }
 298
 299 #ifdef CONFIG_COMPAT
 300 long ext3_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 301 {
 302         struct inode *inode = file->f_path.dentry->d_inode;
 303         int ret;
 304
 305         /* These are just misnamed, they actually get/put from/to user an int */
 306         switch (cmd) {
 307         case EXT3_IOC32_GETFLAGS:
 308                 cmd = EXT3_IOC_GETFLAGS;
 309                 break;
 310         case EXT3_IOC32_SETFLAGS:
 311                 cmd = EXT3_IOC_SETFLAGS;
 312                 break;
 313         case EXT3_IOC32_GETVERSION:
 314                 cmd = EXT3_IOC_GETVERSION;
 315                 break;
 316         case EXT3_IOC32_SETVERSION:
 317                 cmd = EXT3_IOC_SETVERSION;
 318                 break;
 319         case EXT3_IOC32_GROUP_EXTEND:
 320                 cmd = EXT3_IOC_GROUP_EXTEND;
 321                 break;
 322         case EXT3_IOC32_GETVERSION_OLD:
 323                 cmd = EXT3_IOC_GETVERSION_OLD;
 324                 break;
 325         case EXT3_IOC32_SETVERSION_OLD:
 326                 cmd = EXT3_IOC_SETVERSION_OLD;
 327                 break;
 328 #ifdef CONFIG_JBD_DEBUG
 329         case EXT3_IOC32_WAIT_FOR_READONLY:
 330                 cmd = EXT3_IOC_WAIT_FOR_READONLY;
 331                 break;
 332 #endif
 333         case EXT3_IOC32_GETRSVSZ:
 334                 cmd = EXT3_IOC_GETRSVSZ;
 335                 break;
 336         case EXT3_IOC32_SETRSVSZ:
 337                 cmd = EXT3_IOC_SETRSVSZ;
 338                 break;
 339         case EXT3_IOC_GROUP_ADD:
 340                 break;
 341         default:
 342                 return -ENOIOCTLCMD;
 343         }
 344         lock_kernel();
 345         ret = ext3_ioctl(inode, file, cmd, (unsigned long) compat_ptr(arg));
 346         unlock_kernel();
 347         return ret;
 348 }
 349 #endif