/*
 *  arch/s390/kernel/sys_s390.c
 *
 *  S390 version
 *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
 *
 *  Derived from "arch/i386/kernel/sys_i386.c"
 *
 *  This file contains various random system calls that
 *  have a non-standard calling sequence on the Linux/s390
 *  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/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 * 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;
}

/* common code for old and new mmaps */
static inline long do_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;

        flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
        if (!(flags & MAP_ANONYMOUS)) {
                file = fget(fd);
                if (!file)
                        goto out;
        }

        down_write(&current->mm->mmap_sem);
        error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
        up_write(&current->mm->mmap_sem);

        if (file)
                fput(file);
out:
        return error;
}

/*
 * Perform the select(nd, in, out, ex, tv) and mmap() system
 * calls. Linux for S/390 isn't able to handle more than 5
 * 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 long sys_mmap2(struct mmap_arg_struct *arg)
{
        struct mmap_arg_struct a;
        int error = -EFAULT;

        if (copy_from_user(&a, arg, sizeof(a)))
                goto out;
        error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
out:
        return error;
}

asmlinkage int old_mmap(struct mmap_arg_struct *arg)
{
        struct mmap_arg_struct a;
        int error = -EFAULT;

        if (copy_from_user(&a, arg, sizeof(a)))
                goto out;

        error = -EINVAL;
        if (a.offset & ~PAGE_MASK)
                goto out;

        error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
out:
        return error;
}

extern asmlinkage int sys_select(int, fd_set *, fd_set *, fd_set *, struct timeval *);

struct sel_arg_struct {
        unsigned long n;
        fd_set *inp, *outp, *exp;
        struct timeval *tvp;
};

asmlinkage int old_select(struct sel_arg_struct *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 *ptr)
{
        struct ipc_kludge tmp;
        int ret;

        switch (call) {
        case SEMOP:
                return sys_semop (first, (struct sembuf *)ptr, second);
        case SEMGET:
                return sys_semget (first, second, third);
        case SEMCTL: {
                union semun fourth;
                if (!ptr)
                        return -EINVAL;
                if (get_user(fourth.__pad, (void **) ptr))
                        return -EFAULT;
                return sys_semctl (first, second, third, fourth);
        } 
        case MSGSND:
                return sys_msgsnd (first, (struct msgbuf *) ptr, 
                                   second, third);
                break;
        case MSGRCV:
                if (!ptr)
                        return -EINVAL;
                if (copy_from_user (&tmp, (struct ipc_kludge *) ptr,
                                    sizeof (struct ipc_kludge)))
                        return -EFAULT;
                return sys_msgrcv (first, tmp.msgp,
                                   second, tmp.msgtyp, third);
        case MSGGET:
                return sys_msgget ((key_t) first, second);
        case MSGCTL:
                return sys_msgctl (first, second, (struct msqid_ds *) ptr);
                
        case SHMAT: {
                ulong raddr;
                ret = sys_shmat (first, (char *) ptr, second, &raddr);
                if (ret)
                        return ret;
                return put_user (raddr, (ulong *) third);
                break;
        }
        case SHMDT: 
                return sys_shmdt ((char *)ptr);
        case SHMGET:
                return sys_shmget (first, second, third);
        case SHMCTL:
                return sys_shmctl (first, second,
                                   (struct shmid_ds *) ptr);
        default:
                return -EINVAL;

        }
        
        return -EINVAL;
}

/*
 * Old cruft
 */
asmlinkage int sys_uname(struct old_utsname * 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 * 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;
}

asmlinkage int sys_pause(void)
{
        set_current_state(TASK_INTERRUPTIBLE);
        schedule();
        return -ERESTARTNOHAND;
}

asmlinkage int sys_ioperm(unsigned long from, unsigned long num, int on)
{
  return -ENOSYS;
}