LXR linux/arch/powerpc/kernel/syscalls.c

   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 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 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