1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  Implementation of various system calls for Linux/PowerPC
4 *
5 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
6 *
7 * Derived from "arch/i386/kernel/sys_i386.c"
8 * Adapted from the i386 version by Gary Thomas
9 * Modified by Cort Dougan (cort@cs.nmt.edu)
10 * and Paul Mackerras (paulus@cs.anu.edu.au).
11 *
12 * This file contains various random system calls that
13 * have a non-standard calling sequence on the Linux/PPC
14 * platform.
15 */
16
17#include <linux/errno.h>
18#include <linux/sched.h>
19#include <linux/syscalls.h>
20#include <linux/mm.h>
21#include <linux/fs.h>
22#include <linux/smp.h>
23#include <linux/sem.h>
24#include <linux/msg.h>
25#include <linux/shm.h>
26#include <linux/stat.h>
27#include <linux/mman.h>
28#include <linux/sys.h>
29#include <linux/ipc.h>
30#include <linux/utsname.h>
31#include <linux/file.h>
32#include <linux/personality.h>
33
34#include <linux/uaccess.h>
35#include <asm/syscalls.h>
36#include <asm/time.h>
37#include <asm/unistd.h>
38#include <asm/asm-prototypes.h>
39
40static inline long do_mmap2(unsigned long addr, size_t len,
41			unsigned long prot, unsigned long flags,
42			unsigned long fd, unsigned long off, int shift)
43{
44	long ret = -EINVAL;
45
46	if (!arch_validate_prot(prot, addr))
47		goto out;
48
49	if (shift) {
50		if (off & ((1 << shift) - 1))
51			goto out;
52		off >>= shift;
53	}
54
55	ret = ksys_mmap_pgoff(addr, len, prot, flags, fd, off);
56out:
57	return ret;
58}
59
60SYSCALL_DEFINE6(mmap2, unsigned long, addr, size_t, len,
61		unsigned long, prot, unsigned long, flags,
62		unsigned long, fd, unsigned long, pgoff)
63{
64	return do_mmap2(addr, len, prot, flags, fd, pgoff, PAGE_SHIFT-12);
65}
66
67SYSCALL_DEFINE6(mmap, unsigned long, addr, size_t, len,
68		unsigned long, prot, unsigned long, flags,
69		unsigned long, fd, off_t, offset)
70{
71	return do_mmap2(addr, len, prot, flags, fd, offset, PAGE_SHIFT);
72}
73
74#ifdef CONFIG_PPC32
75/*
76 * Due to some executables calling the wrong select we sometimes
77 * get wrong args.  This determines how the args are being passed
78 * (a single ptr to them all args passed) then calls
79 * sys_select() with the appropriate args. -- Cort
80 */
81int
82ppc_select(int n, fd_set __user *inp, fd_set __user *outp, fd_set __user *exp, struct __kernel_old_timeval __user *tvp)
83{
84	if ( (unsigned long)n >= 4096 )
85	{
86		unsigned long __user *buffer = (unsigned long __user *)n;
87		if (!access_ok(buffer, 5*sizeof(unsigned long))
88		    || __get_user(n, buffer)
89		    || __get_user(inp, ((fd_set __user * __user *)(buffer+1)))
90		    || __get_user(outp, ((fd_set  __user * __user *)(buffer+2)))
91		    || __get_user(exp, ((fd_set  __user * __user *)(buffer+3)))
92		    || __get_user(tvp, ((struct __kernel_old_timeval  __user * __user *)(buffer+4))))
93			return -EFAULT;
94	}
95	return sys_select(n, inp, outp, exp, tvp);
96}
97#endif
98
99#ifdef CONFIG_PPC64
100long ppc64_personality(unsigned long personality)
101{
102	long ret;
103
104	if (personality(current->personality) == PER_LINUX32
105	    && personality(personality) == PER_LINUX)
106		personality = (personality & ~PER_MASK) | PER_LINUX32;
107	ret = sys_personality(personality);
108	if (personality(ret) == PER_LINUX32)
109		ret = (ret & ~PER_MASK) | PER_LINUX;
110	return ret;
111}
112#endif
113
114long ppc_fadvise64_64(int fd, int advice, u32 offset_high, u32 offset_low,
115		      u32 len_high, u32 len_low)
116{
117	return ksys_fadvise64_64(fd, (u64)offset_high << 32 | offset_low,
118				 (u64)len_high << 32 | len_low, advice);
119}
120
121SYSCALL_DEFINE0(switch_endian)
122{
123	struct thread_info *ti;
124
125	current->thread.regs->msr ^= MSR_LE;
126
127	/*
128	 * Set TIF_RESTOREALL so that r3 isn't clobbered on return to
129	 * userspace. That also has the effect of restoring the non-volatile
130	 * GPRs, so we saved them on the way in here.
131	 */
132	ti = current_thread_info();
133	ti->flags |= _TIF_RESTOREALL;
134
135	return 0;
136}
137