linux/arch/i386/kernel/sys_i386.c

246 lines
5.7 KiB
C

/*
* linux/arch/i386/kernel/sys_i386.c
*
* This file contains various random system calls that
* have a non-standard calling sequence on the Linux/i386
* platform.
*/
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/sem.h>
#include <linux/msg.h>
#include <linux/shm.h>
#include <linux/stat.h>
#include <linux/syscalls.h>
#include <linux/mman.h>
#include <linux/file.h>
#include <linux/utsname.h>
#include <asm/uaccess.h>
#include <asm/ipc.h>
/*
* sys_pipe() is the normal C calling standard for creating
* a pipe. It's not the way Unix traditionally does this, though.
*/
asmlinkage int sys_pipe(unsigned long __user * fildes)
{
int fd[2];
int error;
error = do_pipe(fd);
if (!error) {
if (copy_to_user(fildes, fd, 2*sizeof(int)))
error = -EFAULT;
}
return error;
}
asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
unsigned long prot, unsigned long flags,
unsigned long fd, unsigned long pgoff)
{
int error = -EBADF;
struct file *file = NULL;
struct mm_struct *mm = current->mm;
flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
if (!(flags & MAP_ANONYMOUS)) {
file = fget(fd);
if (!file)
goto out;
}
down_write(&mm->mmap_sem);
error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
up_write(&mm->mmap_sem);
if (file)
fput(file);
out:
return error;
}
/*
* Perform the select(nd, in, out, ex, tv) and mmap() system
* calls. Linux/i386 didn't use to be able to handle more than
* 4 system call parameters, so these system calls used a memory
* block for parameter passing..
*/
struct mmap_arg_struct {
unsigned long addr;
unsigned long len;
unsigned long prot;
unsigned long flags;
unsigned long fd;
unsigned long offset;
};
asmlinkage int old_mmap(struct mmap_arg_struct __user *arg)
{
struct mmap_arg_struct a;
int err = -EFAULT;
if (copy_from_user(&a, arg, sizeof(a)))
goto out;
err = -EINVAL;
if (a.offset & ~PAGE_MASK)
goto out;
err = sys_mmap2(a.addr, a.len, a.prot, a.flags,
a.fd, a.offset >> PAGE_SHIFT);
out:
return err;
}
struct sel_arg_struct {
unsigned long n;
fd_set __user *inp, *outp, *exp;
struct timeval __user *tvp;
};
asmlinkage int old_select(struct sel_arg_struct __user *arg)
{
struct sel_arg_struct a;
if (copy_from_user(&a, arg, sizeof(a)))
return -EFAULT;
/* sys_select() does the appropriate kernel locking */
return sys_select(a.n, a.inp, a.outp, a.exp, a.tvp);
}
/*
* sys_ipc() is the de-multiplexer for the SysV IPC calls..
*
* This is really horribly ugly.
*/
asmlinkage int sys_ipc (uint call, int first, int second,
int third, void __user *ptr, long fifth)
{
int version, ret;
version = call >> 16; /* hack for backward compatibility */
call &= 0xffff;
switch (call) {
case SEMOP:
return sys_semtimedop (first, (struct sembuf __user *)ptr, second, NULL);
case SEMTIMEDOP:
return sys_semtimedop(first, (struct sembuf __user *)ptr, second,
(const struct timespec __user *)fifth);
case SEMGET:
return sys_semget (first, second, third);
case SEMCTL: {
union semun fourth;
if (!ptr)
return -EINVAL;
if (get_user(fourth.__pad, (void __user * __user *) ptr))
return -EFAULT;
return sys_semctl (first, second, third, fourth);
}
case MSGSND:
return sys_msgsnd (first, (struct msgbuf __user *) ptr,
second, third);
case MSGRCV:
switch (version) {
case 0: {
struct ipc_kludge tmp;
if (!ptr)
return -EINVAL;
if (copy_from_user(&tmp,
(struct ipc_kludge __user *) ptr,
sizeof (tmp)))
return -EFAULT;
return sys_msgrcv (first, tmp.msgp, second,
tmp.msgtyp, third);
}
default:
return sys_msgrcv (first,
(struct msgbuf __user *) ptr,
second, fifth, third);
}
case MSGGET:
return sys_msgget ((key_t) first, second);
case MSGCTL:
return sys_msgctl (first, second, (struct msqid_ds __user *) ptr);
case SHMAT:
switch (version) {
default: {
ulong raddr;
ret = do_shmat (first, (char __user *) ptr, second, &raddr);
if (ret)
return ret;
return put_user (raddr, (ulong __user *) third);
}
case 1: /* iBCS2 emulator entry point */
if (!segment_eq(get_fs(), get_ds()))
return -EINVAL;
/* The "(ulong *) third" is valid _only_ because of the kernel segment thing */
return do_shmat (first, (char __user *) ptr, second, (ulong *) third);
}
case SHMDT:
return sys_shmdt ((char __user *)ptr);
case SHMGET:
return sys_shmget (first, second, third);
case SHMCTL:
return sys_shmctl (first, second,
(struct shmid_ds __user *) ptr);
default:
return -ENOSYS;
}
}
/*
* Old cruft
*/
asmlinkage int sys_uname(struct old_utsname __user * name)
{
int err;
if (!name)
return -EFAULT;
down_read(&uts_sem);
err=copy_to_user(name, &system_utsname, sizeof (*name));
up_read(&uts_sem);
return err?-EFAULT:0;
}
asmlinkage int sys_olduname(struct oldold_utsname __user * name)
{
int error;
if (!name)
return -EFAULT;
if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
return -EFAULT;
down_read(&uts_sem);
error = __copy_to_user(&name->sysname,&system_utsname.sysname,__OLD_UTS_LEN);
error |= __put_user(0,name->sysname+__OLD_UTS_LEN);
error |= __copy_to_user(&name->nodename,&system_utsname.nodename,__OLD_UTS_LEN);
error |= __put_user(0,name->nodename+__OLD_UTS_LEN);
error |= __copy_to_user(&name->release,&system_utsname.release,__OLD_UTS_LEN);
error |= __put_user(0,name->release+__OLD_UTS_LEN);
error |= __copy_to_user(&name->version,&system_utsname.version,__OLD_UTS_LEN);
error |= __put_user(0,name->version+__OLD_UTS_LEN);
error |= __copy_to_user(&name->machine,&system_utsname.machine,__OLD_UTS_LEN);
error |= __put_user(0,name->machine+__OLD_UTS_LEN);
up_read(&uts_sem);
error = error ? -EFAULT : 0;
return error;
}