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/mount.h>
  12 #include <linux/jbd.h>
  13 #include <linux/capability.h>
  14 #include <linux/ext3_fs.h>
  15 #include <linux/ext3_jbd.h>
  16 #include <linux/time.h>
  17 #include <linux/vserver/xid.h>
  18 #include <asm/uaccess.h>
  19
  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                 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_RDONLY(inode) ||
  42                         (filp && MNT_IS_RDONLY(filp->f_vfsmnt)))
  43                         return -EROFS;
  44
  45                 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
  46                         return -EACCES;
  47
  48                 if (get_user(flags, (int __user *) arg))
  49                         return -EFAULT;
  50
  51                 if (!S_ISDIR(inode->i_mode))
  52                         flags &= ~EXT3_DIRSYNC_FL;
  53
  54                 mutex_lock(&inode->i_mutex);
  55                 oldflags = ei->i_flags;
  56
  57                 /* The JOURNAL_DATA flag is modifiable only by root */
  58                 jflag = flags & EXT3_JOURNAL_DATA_FL;
  59
  60                 /*
  61                  * The IMMUTABLE and APPEND_ONLY flags can only be changed by
  62                  * the relevant capability.
  63                  *
  64                  * This test looks nicer. Thanks to Pauline Middelink
  65                  */
  66                 if ((oldflags & EXT3_IMMUTABLE_FL) ||
  67                         ((flags ^ oldflags) & (EXT3_APPEND_FL |
  68                         EXT3_IMMUTABLE_FL | EXT3_IUNLINK_FL))) {
  69                         if (!capable(CAP_LINUX_IMMUTABLE)) {
  70                                 mutex_unlock(&inode->i_mutex);
  71                                 return -EPERM;
  72                         }
  73                 }
  74
  75                 /*
  76                  * The JOURNAL_DATA flag can only be changed by
  77                  * the relevant capability.
  78                  */
  79                 if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL)) {
  80                         if (!capable(CAP_SYS_RESOURCE)) {
  81                                 mutex_unlock(&inode->i_mutex);
  82                                 return -EPERM;
  83                         }
  84                 }
  85
  86
  87                 handle = ext3_journal_start(inode, 1);
  88                 if (IS_ERR(handle)) {
  89                         mutex_unlock(&inode->i_mutex);
  90                         return PTR_ERR(handle);
  91                 }
  92                 if (IS_SYNC(inode))
  93                         handle->h_sync = 1;
  94                 err = ext3_reserve_inode_write(handle, inode, &iloc);
  95                 if (err)
  96                         goto flags_err;
  97
  98                 flags = flags & EXT3_FL_USER_MODIFIABLE;
  99                 flags |= oldflags & ~EXT3_FL_USER_MODIFIABLE;
 100                 ei->i_flags = flags;
 101
 102                 ext3_set_inode_flags(inode);
 103                 inode->i_ctime = CURRENT_TIME_SEC;
 104
 105                 err = ext3_mark_iloc_dirty(handle, inode, &iloc);
 106 flags_err:
 107                 ext3_journal_stop(handle);
 108                 if (err) {
 109                         mutex_unlock(&inode->i_mutex);
 110                         return err;
 111                 }
 112
 113                 if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL))
 114                         err = ext3_change_inode_journal_flag(inode, jflag);
 115                 mutex_unlock(&inode->i_mutex);
 116                 return err;
 117         }
 118         case EXT3_IOC_GETVERSION:
 119         case EXT3_IOC_GETVERSION_OLD:
 120                 return put_user(inode->i_generation, (int __user *) arg);
 121         case EXT3_IOC_SETVERSION:
 122         case EXT3_IOC_SETVERSION_OLD: {
 123                 handle_t *handle;
 124                 struct ext3_iloc iloc;
 125                 __u32 generation;
 126                 int err;
 127
 128                 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
 129                         return -EPERM;
 130                 if (IS_RDONLY(inode) ||
 131                         (filp && MNT_IS_RDONLY(filp->f_vfsmnt)))
 132                         return -EROFS;
 133                 if (get_user(generation, (int __user *) arg))
 134                         return -EFAULT;
 135
 136                 handle = ext3_journal_start(inode, 1);
 137                 if (IS_ERR(handle))
 138                         return PTR_ERR(handle);
 139                 err = ext3_reserve_inode_write(handle, inode, &iloc);
 140                 if (err == 0) {
 141                         inode->i_ctime = CURRENT_TIME_SEC;
 142                         inode->i_generation = generation;
 143                         err = ext3_mark_iloc_dirty(handle, inode, &iloc);
 144                 }
 145                 ext3_journal_stop(handle);
 146                 return err;
 147         }
 148 #ifdef CONFIG_JBD_DEBUG
 149         case EXT3_IOC_WAIT_FOR_READONLY:
 150                 /*
 151                  * This is racy - by the time we're woken up and running,
 152                  * the superblock could be released.  And the module could
 153                  * have been unloaded.  So sue me.
 154                  *
 155                  * Returns 1 if it slept, else zero.
 156                  */
 157                 {
 158                         struct super_block *sb = inode->i_sb;
 159                         DECLARE_WAITQUEUE(wait, current);
 160                         int ret = 0;
 161
 162                         set_current_state(TASK_INTERRUPTIBLE);
 163                         add_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait);
 164                         if (timer_pending(&EXT3_SB(sb)->turn_ro_timer)) {
 165                                 schedule();
 166                                 ret = 1;
 167                         }
 168                         remove_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait);
 169                         return ret;
 170                 }
 171 #endif
 172         case EXT3_IOC_GETRSVSZ:
 173                 if (test_opt(inode->i_sb, RESERVATION)
 174                         && S_ISREG(inode->i_mode)
 175                         && ei->i_block_alloc_info) {
 176                         rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
 177                         return put_user(rsv_window_size, (int __user *)arg);
 178                 }
 179                 return -ENOTTY;
 180         case EXT3_IOC_SETRSVSZ: {
 181
 182                 if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
 183                         return -ENOTTY;
 184
 185                 if (IS_RDONLY(inode) ||
 186                         (filp && MNT_IS_RDONLY(filp->f_vfsmnt)))
 187                         return -EROFS;
 188
 189                 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
 190                         return -EACCES;
 191
 192                 if (get_user(rsv_window_size, (int __user *)arg))
 193                         return -EFAULT;
 194
 195                 if (rsv_window_size > EXT3_MAX_RESERVE_BLOCKS)
 196                         rsv_window_size = EXT3_MAX_RESERVE_BLOCKS;
 197
 198                 /*
 199                  * need to allocate reservation structure for this inode
 200                  * before set the window size
 201                  */
 202                 mutex_lock(&ei->truncate_mutex);
 203                 if (!ei->i_block_alloc_info)
 204                         ext3_init_block_alloc_info(inode);
 205
 206                 if (ei->i_block_alloc_info){
 207                         struct ext3_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
 208                         rsv->rsv_goal_size = rsv_window_size;
 209                 }
 210                 mutex_unlock(&ei->truncate_mutex);
 211                 return 0;
 212         }
 213         case EXT3_IOC_GROUP_EXTEND: {
 214                 ext3_fsblk_t n_blocks_count;
 215                 struct super_block *sb = inode->i_sb;
 216                 int err;
 217
 218                 if (!capable(CAP_SYS_RESOURCE))
 219                         return -EPERM;
 220
 221                 if (IS_RDONLY(inode) ||
 222                         (filp && MNT_IS_RDONLY(filp->f_vfsmnt)))
 223                         return -EROFS;
 224
 225                 if (get_user(n_blocks_count, (__u32 __user *)arg))
 226                         return -EFAULT;
 227
 228                 err = ext3_group_extend(sb, EXT3_SB(sb)->s_es, n_blocks_count);
 229                 journal_lock_updates(EXT3_SB(sb)->s_journal);
 230                 journal_flush(EXT3_SB(sb)->s_journal);
 231                 journal_unlock_updates(EXT3_SB(sb)->s_journal);
 232
 233                 return err;
 234         }
 235         case EXT3_IOC_GROUP_ADD: {
 236                 struct ext3_new_group_data input;
 237                 struct super_block *sb = inode->i_sb;
 238                 int err;
 239
 240                 if (!capable(CAP_SYS_RESOURCE))
 241                         return -EPERM;
 242
 243                 if (IS_RDONLY(inode) ||
 244                         (filp && MNT_IS_RDONLY(filp->f_vfsmnt)))
 245                         return -EROFS;
 246
 247                 if (copy_from_user(&input, (struct ext3_new_group_input __user *)arg,
 248                                 sizeof(input)))
 249                         return -EFAULT;
 250
 251                 err = ext3_group_add(sb, &input);
 252                 journal_lock_updates(EXT3_SB(sb)->s_journal);
 253                 journal_flush(EXT3_SB(sb)->s_journal);
 254                 journal_unlock_updates(EXT3_SB(sb)->s_journal);
 255
 256                 return err;
 257         }
 258
 259 #if defined(CONFIG_VSERVER_LEGACY) && !defined(CONFIG_INOXID_NONE)
 260         case EXT3_IOC_SETXID: {
 261                 handle_t *handle;
 262                 struct ext3_iloc iloc;
 263                 int xid;
 264                 int err;
 265
 266                 /* fixme: if stealth, return -ENOTTY */
 267                 if (!capable(CAP_CONTEXT))
 268                         return -EPERM;
 269                 if (IS_RDONLY(inode))
 270                         return -EROFS;
 271                 if (!(inode->i_sb->s_flags & MS_TAGXID))
 272                         return -ENOSYS;
 273                 if (get_user(xid, (int __user *) arg))
 274                         return -EFAULT;
 275
 276                 handle = ext3_journal_start(inode, 1);
 277                 if (IS_ERR(handle))
 278                         return PTR_ERR(handle);
 279                 err = ext3_reserve_inode_write(handle, inode, &iloc);
 280                 if (err)
 281                         return err;
 282
 283                 inode->i_xid = (xid & 0xFFFF);
 284                 inode->i_ctime = CURRENT_TIME;
 285
 286                 err = ext3_mark_iloc_dirty(handle, inode, &iloc);
 287                 ext3_journal_stop(handle);
 288                 return err;
 289         }
 290 #endif
 291
 292         default:
 293                 return -ENOTTY;
 294         }
 295 }