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/ext3_fs.h>
  13 #include <linux/ext3_jbd.h>
  14 #include <linux/time.h>
  15 #include <linux/vserver/xid.h>
  16 #include <asm/uaccess.h>
  17
  18
  19 int ext3_ioctl (struct inode * inode, struct file * filp, unsigned int cmd,
  20                 unsigned long arg)
  21 {
  22         struct ext3_inode_info *ei = EXT3_I(inode);
  23         unsigned int flags;
  24         unsigned short rsv_window_size;
  25
  26         ext3_debug ("cmd = %u, arg = %lu\n", cmd, arg);
  27
  28         switch (cmd) {
  29         case EXT3_IOC_GETFLAGS:
  30                 flags = ei->i_flags & EXT3_FL_USER_VISIBLE;
  31                 return put_user(flags, (int __user *) arg);
  32         case EXT3_IOC_SETFLAGS: {
  33                 handle_t *handle = NULL;
  34                 int err;
  35                 struct ext3_iloc iloc;
  36                 unsigned int oldflags;
  37                 unsigned int jflag;
  38
  39                 if (IS_RDONLY(inode))
  40                         return -EROFS;
  41
  42                 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
  43                         return -EACCES;
  44
  45                 if (get_user(flags, (int __user *) arg))
  46                         return -EFAULT;
  47
  48                 if (!S_ISDIR(inode->i_mode))
  49                         flags &= ~EXT3_DIRSYNC_FL;
  50
  51                 oldflags = ei->i_flags;
  52
  53                 /* The JOURNAL_DATA flag is modifiable only by root */
  54                 jflag = flags & EXT3_JOURNAL_DATA_FL;
  55
  56                 /*
  57                  * The IMMUTABLE and APPEND_ONLY flags can only be changed by
  58                  * the relevant capability.
  59                  *
  60                  * This test looks nicer. Thanks to Pauline Middelink
  61                  */
  62                 if ((oldflags & EXT3_IMMUTABLE_FL) ||
  63                         ((flags ^ oldflags) & (EXT3_APPEND_FL |
  64                         EXT3_IMMUTABLE_FL | EXT3_IUNLINK_FL))) {
  65                         if (!capable(CAP_LINUX_IMMUTABLE))
  66                                 return -EPERM;
  67                 }
  68
  69                 /*
  70                  * The JOURNAL_DATA flag can only be changed by
  71                  * the relevant capability.
  72                  */
  73                 if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL)) {
  74                         if (!capable(CAP_SYS_RESOURCE))
  75                                 return -EPERM;
  76                 }
  77
  78
  79                 handle = ext3_journal_start(inode, 1);
  80                 if (IS_ERR(handle))
  81                         return PTR_ERR(handle);
  82                 if (IS_SYNC(inode))
  83                         handle->h_sync = 1;
  84                 err = ext3_reserve_inode_write(handle, inode, &iloc);
  85                 if (err)
  86                         goto flags_err;
  87
  88                 flags = flags & EXT3_FL_USER_MODIFIABLE;
  89                 flags |= oldflags & ~EXT3_FL_USER_MODIFIABLE;
  90                 ei->i_flags = flags;
  91
  92                 ext3_set_inode_flags(inode);
  93                 inode->i_ctime = CURRENT_TIME_SEC;
  94
  95                 err = ext3_mark_iloc_dirty(handle, inode, &iloc);
  96 flags_err:
  97                 ext3_journal_stop(handle);
  98                 if (err)
  99                         return err;
 100
 101                 if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL))
 102                         err = ext3_change_inode_journal_flag(inode, jflag);
 103                 return err;
 104         }
 105         case EXT3_IOC_GETVERSION:
 106         case EXT3_IOC_GETVERSION_OLD:
 107                 return put_user(inode->i_generation, (int __user *) arg);
 108         case EXT3_IOC_SETVERSION:
 109         case EXT3_IOC_SETVERSION_OLD: {
 110                 handle_t *handle;
 111                 struct ext3_iloc iloc;
 112                 __u32 generation;
 113                 int err;
 114
 115                 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
 116                         return -EPERM;
 117                 if (IS_RDONLY(inode))
 118                         return -EROFS;
 119                 if (get_user(generation, (int __user *) arg))
 120                         return -EFAULT;
 121
 122                 handle = ext3_journal_start(inode, 1);
 123                 if (IS_ERR(handle))
 124                         return PTR_ERR(handle);
 125                 err = ext3_reserve_inode_write(handle, inode, &iloc);
 126                 if (err == 0) {
 127                         inode->i_ctime = CURRENT_TIME_SEC;
 128                         inode->i_generation = generation;
 129                         err = ext3_mark_iloc_dirty(handle, inode, &iloc);
 130                 }
 131                 ext3_journal_stop(handle);
 132                 return err;
 133         }
 134 #ifdef CONFIG_JBD_DEBUG
 135         case EXT3_IOC_WAIT_FOR_READONLY:
 136                 /*
 137                  * This is racy - by the time we're woken up and running,
 138                  * the superblock could be released.  And the module could
 139                  * have been unloaded.  So sue me.
 140                  *
 141                  * Returns 1 if it slept, else zero.
 142                  */
 143                 {
 144                         struct super_block *sb = inode->i_sb;
 145                         DECLARE_WAITQUEUE(wait, current);
 146                         int ret = 0;
 147
 148                         set_current_state(TASK_INTERRUPTIBLE);
 149                         add_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait);
 150                         if (timer_pending(&EXT3_SB(sb)->turn_ro_timer)) {
 151                                 schedule();
 152                                 ret = 1;
 153                         }
 154                         remove_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait);
 155                         return ret;
 156                 }
 157 #endif
 158         case EXT3_IOC_GETRSVSZ:
 159                 if (test_opt(inode->i_sb, RESERVATION)
 160                         && S_ISREG(inode->i_mode)
 161                         && ei->i_block_alloc_info) {
 162                         rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
 163                         return put_user(rsv_window_size, (int __user *)arg);
 164                 }
 165                 return -ENOTTY;
 166         case EXT3_IOC_SETRSVSZ: {
 167
 168                 if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
 169                         return -ENOTTY;
 170
 171                 if (IS_RDONLY(inode))
 172                         return -EROFS;
 173
 174                 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
 175                         return -EACCES;
 176
 177                 if (get_user(rsv_window_size, (int __user *)arg))
 178                         return -EFAULT;
 179
 180                 if (rsv_window_size > EXT3_MAX_RESERVE_BLOCKS)
 181                         rsv_window_size = EXT3_MAX_RESERVE_BLOCKS;
 182
 183                 /*
 184                  * need to allocate reservation structure for this inode
 185                  * before set the window size
 186                  */
 187                 down(&ei->truncate_sem);
 188                 if (!ei->i_block_alloc_info)
 189                         ext3_init_block_alloc_info(inode);
 190
 191                 if (ei->i_block_alloc_info){
 192                         struct ext3_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
 193                         rsv->rsv_goal_size = rsv_window_size;
 194                 }
 195                 up(&ei->truncate_sem);
 196                 return 0;
 197         }
 198         case EXT3_IOC_GROUP_EXTEND: {
 199                 unsigned long n_blocks_count;
 200                 struct super_block *sb = inode->i_sb;
 201                 int err;
 202
 203                 if (!capable(CAP_SYS_RESOURCE))
 204                         return -EPERM;
 205
 206                 if (IS_RDONLY(inode))
 207                         return -EROFS;
 208
 209                 if (get_user(n_blocks_count, (__u32 __user *)arg))
 210                         return -EFAULT;
 211
 212                 err = ext3_group_extend(sb, EXT3_SB(sb)->s_es, n_blocks_count);
 213                 journal_lock_updates(EXT3_SB(sb)->s_journal);
 214                 journal_flush(EXT3_SB(sb)->s_journal);
 215                 journal_unlock_updates(EXT3_SB(sb)->s_journal);
 216
 217                 return err;
 218         }
 219         case EXT3_IOC_GROUP_ADD: {
 220                 struct ext3_new_group_data input;
 221                 struct super_block *sb = inode->i_sb;
 222                 int err;
 223
 224                 if (!capable(CAP_SYS_RESOURCE))
 225                         return -EPERM;
 226
 227                 if (IS_RDONLY(inode))
 228                         return -EROFS;
 229
 230                 if (copy_from_user(&input, (struct ext3_new_group_input __user *)arg,
 231                                 sizeof(input)))
 232                         return -EFAULT;
 233
 234                 err = ext3_group_add(sb, &input);
 235                 journal_lock_updates(EXT3_SB(sb)->s_journal);
 236                 journal_flush(EXT3_SB(sb)->s_journal);
 237                 journal_unlock_updates(EXT3_SB(sb)->s_journal);
 238
 239                 return err;
 240         }
 241
 242 #if defined(CONFIG_VSERVER_LEGACY) && !defined(CONFIG_INOXID_NONE)
 243         case EXT3_IOC_SETXID: {
 244                 handle_t *handle;
 245                 struct ext3_iloc iloc;
 246                 int xid;
 247                 int err;
 248
 249                 /* fixme: if stealth, return -ENOTTY */
 250                 if (!capable(CAP_CONTEXT))
 251                         return -EPERM;
 252                 if (IS_RDONLY(inode))
 253                         return -EROFS;
 254                 if (!(inode->i_sb->s_flags & MS_TAGXID))
 255                         return -ENOSYS;
 256                 if (get_user(xid, (int *) arg))
 257                         return -EFAULT;
 258
 259                 handle = ext3_journal_start(inode, 1);
 260                 if (IS_ERR(handle))
 261                         return PTR_ERR(handle);
 262                 err = ext3_reserve_inode_write(handle, inode, &iloc);
 263                 if (err)
 264                         return err;
 265
 266                 inode->i_xid = (xid & 0xFFFF);
 267                 inode->i_ctime = CURRENT_TIME;
 268
 269                 err = ext3_mark_iloc_dirty(handle, inode, &iloc);
 270                 ext3_journal_stop(handle);
 271                 return err;
 272         }
 273 #endif
 274
 275         default:
 276                 return -ENOTTY;
 277         }
 278 }