aboutsummaryrefslogtreecommitdiff
path: root/arch/s390/kernel/sys_s390.c
blob: 78ea1948ff514f4e20df0686f38308427644fe21 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
/*
 *  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),
 *               Thomas Spatzier (tspat@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/fs.h>
#include <linux/smp.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 <linux/personality.h>
#include <linux/unistd.h>
#include <linux/ipc.h>
#include <asm/uaccess.h>
#include "entry.h"

/*
 * Perform the mmap() system call. Linux for S/390 isn't able to handle more
 * than 5 system call parameters, so this system call uses a memory block
 * for parameter passing.
 */

struct s390_mmap_arg_struct {
	unsigned long addr;
	unsigned long len;
	unsigned long prot;
	unsigned long flags;
	unsigned long fd;
	unsigned long offset;
};

SYSCALL_DEFINE1(mmap2, struct s390_mmap_arg_struct __user *, arg)
{
	struct s390_mmap_arg_struct a;
	int error = -EFAULT;

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

/*
 * sys_ipc() is the de-multiplexer for the SysV IPC calls.
 */
SYSCALL_DEFINE5(s390_ipc, uint, call, int, first, unsigned long, second,
		unsigned long, third, void __user *, ptr)
{
	if (call >> 16)
		return -EINVAL;
	/* The s390 sys_ipc variant has only five parameters instead of six
	 * like the generic variant. The only difference is the handling of
	 * the SEMTIMEDOP subcall where on s390 the third parameter is used
	 * as a pointer to a struct timespec where the generic variant uses
	 * the fifth parameter.
	 * Therefore we can call the generic variant by simply passing the
	 * third parameter also as fifth parameter.
	 */
	return sys_ipc(call, first, second, third, ptr, third);
}

#ifdef CONFIG_64BIT
SYSCALL_DEFINE1(s390_personality, unsigned int, personality)
{
	unsigned int ret;

	if (current->personality == PER_LINUX32 && personality == PER_LINUX)
		personality = PER_LINUX32;
	ret = sys_personality(personality);
	if (ret == PER_LINUX32)
		ret = PER_LINUX;

	return ret;
}
#endif /* CONFIG_64BIT */

/*
 * Wrapper function for sys_fadvise64/fadvise64_64
 */
#ifndef CONFIG_64BIT

SYSCALL_DEFINE5(s390_fadvise64, int, fd, u32, offset_high, u32, offset_low,
		size_t, len, int, advice)
{
	return sys_fadvise64(fd, (u64) offset_high << 32 | offset_low,
			len, advice);
}

struct fadvise64_64_args {
	int fd;
	long long offset;
	long long len;
	int advice;
};

SYSCALL_DEFINE1(s390_fadvise64_64, struct fadvise64_64_args __user *, args)
{
	struct fadvise64_64_args a;

	if ( copy_from_user(&a, args, sizeof(a)) )
		return -EFAULT;
	return sys_fadvise64_64(a.fd, a.offset, a.len, a.advice);
}

/*
 * This is a wrapper to call sys_fallocate(). For 31 bit s390 the last
 * 64 bit argument "len" is split into the upper and lower 32 bits. The
 * system call wrapper in the user space loads the value to %r6/%r7.
 * The code in entry.S keeps the values in %r2 - %r6 where they are and
 * stores %r7 to 96(%r15). But the standard C linkage requires that
 * the whole 64 bit value for len is stored on the stack and doesn't
 * use %r6 at all. So s390_fallocate has to convert the arguments from
 *   %r2: fd, %r3: mode, %r4/%r5: offset, %r6/96(%r15)-99(%r15): len
 * to
 *   %r2: fd, %r3: mode, %r4/%r5: offset, 96(%r15)-103(%r15): len
 */
SYSCALL_DEFINE(s390_fallocate)(int fd, int mode, loff_t offset,
			       u32 len_high, u32 len_low)
{
	return sys_fallocate(fd, mode, offset, ((u64)len_high << 32) | len_low);
}
#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
asmlinkage long SyS_s390_fallocate(long fd, long mode, loff_t offset,
				   long len_high, long len_low)
{
	return SYSC_s390_fallocate((int) fd, (int) mode, offset,
				   (u32) len_high, (u32) len_low);
}
SYSCALL_ALIAS(sys_s390_fallocate, SyS_s390_fallocate);
#endif

#endif