arch/s390/kernel/sys_s390.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  S390 version
   4  *    Copyright IBM Corp. 1999, 2000
   5  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
   6  *               Thomas Spatzier (tspat@de.ibm.com)
   7  *
   8  *  Derived from "arch/i386/kernel/sys_i386.c"
   9  *
  10  *  This file contains various random system calls that
  11  *  have a non-standard calling sequence on the Linux/s390
  12  *  platform.
  13  */
  14
  15 #include <linux/errno.h>
  16 #include <linux/sched.h>
  17 #include <linux/mm.h>
  18 #include <linux/fs.h>
  19 #include <linux/smp.h>
  20 #include <linux/sem.h>
  21 #include <linux/msg.h>
  22 #include <linux/shm.h>
  23 #include <linux/stat.h>
  24 #include <linux/syscalls.h>
  25 #include <linux/mman.h>
  26 #include <linux/file.h>
  27 #include <linux/utsname.h>
  28 #include <linux/personality.h>
  29 #include <linux/unistd.h>
  30 #include <linux/ipc.h>
  31 #include <linux/uaccess.h>
  32 #include "entry.h"
  33
  34 /*
  35  * Perform the mmap() system call. Linux for S/390 isn't able to handle more
  36  * than 5 system call parameters, so this system call uses a memory block
  37  * for parameter passing.
  38  */
  39
  40 struct s390_mmap_arg_struct {
  41         unsigned long addr;
  42         unsigned long len;
  43         unsigned long prot;
  44         unsigned long flags;
  45         unsigned long fd;
  46         unsigned long offset;
  47 };
  48
  49 SYSCALL_DEFINE1(mmap2, struct s390_mmap_arg_struct __user *, arg)
  50 {
  51         struct s390_mmap_arg_struct a;
  52         int error = -EFAULT;
  53
  54         if (copy_from_user(&a, arg, sizeof(a)))
  55                 goto out;
  56         error = sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
  57 out:
  58         return error;
  59 }
  60
  61 /*
  62  * sys_ipc() is the de-multiplexer for the SysV IPC calls.
  63  */
  64 SYSCALL_DEFINE5(s390_ipc, uint, call, int, first, unsigned long, second,
  65                 unsigned long, third, void __user *, ptr)
  66 {
  67         if (call >> 16)
  68                 return -EINVAL;
  69         /* The s390 sys_ipc variant has only five parameters instead of six
  70          * like the generic variant. The only difference is the handling of
  71          * the SEMTIMEDOP subcall where on s390 the third parameter is used
  72          * as a pointer to a struct timespec where the generic variant uses
  73          * the fifth parameter.
  74          * Therefore we can call the generic variant by simply passing the
  75          * third parameter also as fifth parameter.
  76          */
  77         return sys_ipc(call, first, second, third, ptr, third);
  78 }
  79
  80 SYSCALL_DEFINE1(s390_personality, unsigned int, personality)
  81 {
  82         unsigned int ret;
  83
  84         if (personality(current->personality) == PER_LINUX32 &&
  85             personality(personality) == PER_LINUX)
  86                 personality |= PER_LINUX32;
  87         ret = sys_personality(personality);
  88         if (personality(ret) == PER_LINUX32)
  89                 ret &= ~PER_LINUX32;
  90
  91         return ret;
  92 }