1/*
  2 *  S390 version
  3 *    Copyright IBM Corp. 1999, 2000
  4 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
  5 *               Thomas Spatzier (tspat@de.ibm.com)
  6 *
  7 *  Derived from "arch/i386/kernel/sys_i386.c"
  8 *
  9 *  This file contains various random system calls that
 10 *  have a non-standard calling sequence on the Linux/s390
 11 *  platform.
 12 */
 13
 14#include <linux/errno.h>
 15#include <linux/sched.h>
 16#include <linux/mm.h>
 17#include <linux/fs.h>
 18#include <linux/smp.h>
 19#include <linux/sem.h>
 20#include <linux/msg.h>
 21#include <linux/shm.h>
 22#include <linux/stat.h>
 23#include <linux/syscalls.h>
 24#include <linux/mman.h>
 25#include <linux/file.h>
 26#include <linux/utsname.h>
 27#include <linux/personality.h>
 28#include <linux/unistd.h>
 29#include <linux/ipc.h>
 30#include <asm/uaccess.h>
 31#include "entry.h"
 32
 33/*
 34 * Perform the mmap() system call. Linux for S/390 isn't able to handle more
 35 * than 5 system call parameters, so this system call uses a memory block
 36 * for parameter passing.
 37 */
 38
 39struct s390_mmap_arg_struct {
 40	unsigned long addr;
 41	unsigned long len;
 42	unsigned long prot;
 43	unsigned long flags;
 44	unsigned long fd;
 45	unsigned long offset;
 46};
 47
 48SYSCALL_DEFINE1(mmap2, struct s390_mmap_arg_struct __user *, arg)
 49{
 50	struct s390_mmap_arg_struct a;
 51	int error = -EFAULT;
 52
 53	if (copy_from_user(&a, arg, sizeof(a)))
 54		goto out;
 55	error = sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
 56out:
 57	return error;
 58}
 59
 60/*
 61 * sys_ipc() is the de-multiplexer for the SysV IPC calls.
 62 */
 63SYSCALL_DEFINE5(s390_ipc, uint, call, int, first, unsigned long, second,
 64		unsigned long, third, void __user *, ptr)
 65{
 66	if (call >> 16)
 67		return -EINVAL;
 68	/* The s390 sys_ipc variant has only five parameters instead of six
 69	 * like the generic variant. The only difference is the handling of
 70	 * the SEMTIMEDOP subcall where on s390 the third parameter is used
 71	 * as a pointer to a struct timespec where the generic variant uses
 72	 * the fifth parameter.
 73	 * Therefore we can call the generic variant by simply passing the
 74	 * third parameter also as fifth parameter.
 75	 */
 76	return sys_ipc(call, first, second, third, ptr, third);
 77}
 78
 79#ifdef CONFIG_64BIT
 80SYSCALL_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}
 93#endif /* CONFIG_64BIT */
 94
 95/*
 96 * Wrapper function for sys_fadvise64/fadvise64_64
 97 */
 98#ifndef CONFIG_64BIT
 99
100SYSCALL_DEFINE5(s390_fadvise64, int, fd, u32, offset_high, u32, offset_low,
101		size_t, len, int, advice)
102{
103	return sys_fadvise64(fd, (u64) offset_high << 32 | offset_low,
104			len, advice);
105}
106
107struct fadvise64_64_args {
108	int fd;
109	long long offset;
110	long long len;
111	int advice;
112};
113
114SYSCALL_DEFINE1(s390_fadvise64_64, struct fadvise64_64_args __user *, args)
115{
116	struct fadvise64_64_args a;
117
118	if ( copy_from_user(&a, args, sizeof(a)) )
119		return -EFAULT;
120	return sys_fadvise64_64(a.fd, a.offset, a.len, a.advice);
121}
122
123/*
124 * This is a wrapper to call sys_fallocate(). For 31 bit s390 the last
125 * 64 bit argument "len" is split into the upper and lower 32 bits. The
126 * system call wrapper in the user space loads the value to %r6/%r7.
127 * The code in entry.S keeps the values in %r2 - %r6 where they are and
128 * stores %r7 to 96(%r15). But the standard C linkage requires that
129 * the whole 64 bit value for len is stored on the stack and doesn't
130 * use %r6 at all. So s390_fallocate has to convert the arguments from
131 *   %r2: fd, %r3: mode, %r4/%r5: offset, %r6/96(%r15)-99(%r15): len
132 * to
133 *   %r2: fd, %r3: mode, %r4/%r5: offset, 96(%r15)-103(%r15): len
134 */
135SYSCALL_DEFINE5(s390_fallocate, int, fd, int, mode, loff_t, offset,
136			       u32, len_high, u32, len_low)
137{
138	return sys_fallocate(fd, mode, offset, ((u64)len_high << 32) | len_low);
139}
140#endif