fs/ioctl.c

   1 /*
   2  *  linux/fs/ioctl.c
   3  *
   4  *  Copyright (C) 1991, 1992  Linus Torvalds
   5  */
   6
   7 #include <linux/config.h>
   8 #include <linux/mm.h>
   9 #include <linux/smp_lock.h>
  10 #include <linux/file.h>
  11 #include <linux/fs.h>
  12 #include <linux/security.h>
  13 #include <linux/module.h>
  14 #include <linux/proc_fs.h>
  15 #include <linux/vserver/inode.h>
  16 #include <linux/vserver/xid.h>
  17
  18 #include <asm/uaccess.h>
  19 #include <asm/ioctls.h>
  20
  21 #ifdef  CONFIG_VSERVER_LEGACY
  22 extern int vx_proc_ioctl(struct inode *, struct file *,
  23         unsigned int, unsigned long);
  24 #endif
  25
  26 static int file_ioctl(struct file *filp,unsigned int cmd,unsigned long arg)
  27 {
  28         int error;
  29         int block;
  30         struct inode * inode = filp->f_dentry->d_inode;
  31         int __user *p = (int __user *)arg;
  32
  33         switch (cmd) {
  34                 case FIBMAP:
  35                 {
  36                         struct address_space *mapping = filp->f_mapping;
  37                         int res;
  38                         /* do we support this mess? */
  39                         if (!mapping->a_ops->bmap)
  40                                 return -EINVAL;
  41                         if (!capable(CAP_SYS_RAWIO))
  42                                 return -EPERM;
  43                         if ((error = get_user(block, p)) != 0)
  44                                 return error;
  45
  46                         res = mapping->a_ops->bmap(mapping, block);
  47                         return put_user(res, p);
  48                 }
  49                 case FIGETBSZ:
  50                         if (inode->i_sb == NULL)
  51                                 return -EBADF;
  52                         return put_user(inode->i_sb->s_blocksize, p);
  53                 case FIONREAD:
  54                         return put_user(i_size_read(inode) - filp->f_pos, p);
  55         }
  56         if (filp->f_op && filp->f_op->ioctl)
  57                 return filp->f_op->ioctl(inode, filp, cmd, arg);
  58         return -ENOTTY;
  59 }
  60
  61
  62 asmlinkage long sys_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
  63 {
  64         struct file * filp;
  65         unsigned int flag;
  66         int on, error = -EBADF;
  67
  68         filp = fget(fd);
  69         if (!filp)
  70                 goto out;
  71
  72         error = security_file_ioctl(filp, cmd, arg);
  73         if (error) {
  74                 fput(filp);
  75                 goto out;
  76         }
  77
  78         lock_kernel();
  79         switch (cmd) {
  80                 case FIOCLEX:
  81                         set_close_on_exec(fd, 1);
  82                         break;
  83
  84                 case FIONCLEX:
  85                         set_close_on_exec(fd, 0);
  86                         break;
  87
  88                 case FIONBIO:
  89                         if ((error = get_user(on, (int __user *)arg)) != 0)
  90                                 break;
  91                         flag = O_NONBLOCK;
  92 #ifdef __sparc__
  93                         /* SunOS compatibility item. */
  94                         if(O_NONBLOCK != O_NDELAY)
  95                                 flag |= O_NDELAY;
  96 #endif
  97                         if (on)
  98                                 filp->f_flags |= flag;
  99                         else
 100                                 filp->f_flags &= ~flag;
 101                         break;
 102
 103                 case FIOASYNC:
 104                         if ((error = get_user(on, (int __user *)arg)) != 0)
 105                                 break;
 106                         flag = on ? FASYNC : 0;
 107
 108                         /* Did FASYNC state change ? */
 109                         if ((flag ^ filp->f_flags) & FASYNC) {
 110                                 if (filp->f_op && filp->f_op->fasync)
 111                                         error = filp->f_op->fasync(fd, filp, on);
 112                                 else error = -ENOTTY;
 113                         }
 114                         if (error != 0)
 115                                 break;
 116
 117                         if (on)
 118                                 filp->f_flags |= FASYNC;
 119                         else
 120                                 filp->f_flags &= ~FASYNC;
 121                         break;
 122
 123                 case FIOQSIZE:
 124                         if (S_ISDIR(filp->f_dentry->d_inode->i_mode) ||
 125                             S_ISREG(filp->f_dentry->d_inode->i_mode) ||
 126                             S_ISLNK(filp->f_dentry->d_inode->i_mode)) {
 127                                 loff_t res = inode_get_bytes(filp->f_dentry->d_inode);
 128                                 error = copy_to_user((loff_t __user *)arg, &res, sizeof(res)) ? -EFAULT : 0;
 129                         }
 130                         else
 131                                 error = -ENOTTY;
 132                         break;
 133 #ifdef  CONFIG_VSERVER_LEGACY
 134 #ifndef CONFIG_INOXID_NONE
 135                 case FIOC_GETXID: {
 136                         struct inode *inode = filp->f_dentry->d_inode;
 137
 138                         /* fixme: if stealth, return -ENOTTY */
 139                         error = -EPERM;
 140                         if (capable(CAP_CONTEXT))
 141                                 error = put_user(inode->i_xid, (int *) arg);
 142                         break;
 143                 }
 144                 case FIOC_SETXID: {
 145                         struct inode *inode = filp->f_dentry->d_inode;
 146                         int xid;
 147
 148                         /* fixme: if stealth, return -ENOTTY */
 149                         error = -EPERM;
 150                         if (!capable(CAP_CONTEXT))
 151                                 break;
 152                         error = -EROFS;
 153                         if (IS_RDONLY(inode))
 154                                 break;
 155                         error = -ENOSYS;
 156                         if (!(inode->i_sb->s_flags & MS_TAGXID))
 157                                 break;
 158                         error = -EFAULT;
 159                         if (get_user(xid, (int *) arg))
 160                                 break;
 161                         error = 0;
 162                         inode->i_xid = (xid & 0xFFFF);
 163                         inode->i_ctime = CURRENT_TIME;
 164                         mark_inode_dirty(inode);
 165                         break;
 166                 }
 167 #endif
 168                 case FIOC_GETXFLG:
 169                 case FIOC_SETXFLG:
 170                         error = -ENOTTY;
 171                         if (filp->f_dentry->d_inode->i_sb->s_magic == PROC_SUPER_MAGIC)
 172                                 error = vx_proc_ioctl(filp->f_dentry->d_inode, filp, cmd, arg);
 173                         break;
 174 #endif
 175                 default:
 176                         error = -ENOTTY;
 177                         if (S_ISREG(filp->f_dentry->d_inode->i_mode))
 178                                 error = file_ioctl(filp, cmd, arg);
 179                         else if (filp->f_op && filp->f_op->ioctl)
 180                                 error = filp->f_op->ioctl(filp->f_dentry->d_inode, filp, cmd, arg);
 181         }
 182         unlock_kernel();
 183         fput(filp);
 184
 185 out:
 186         return error;
 187 }
 188
 189 /*
 190  * Platforms implementing 32 bit compatibility ioctl handlers in
 191  * modules need this exported
 192  */
 193 #ifdef CONFIG_COMPAT
 194 EXPORT_SYMBOL(sys_ioctl);
 195 #endif